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Saturday, February 26, 2022

Slavery in colonial Spanish America

Slavery in the Spanish American colonies was an economic and social institution which existed throughout the Spanish Empire including Spain itself. In its American territories, Spain displayed an early abolitionist stance towards indigenous people although Native American slavery continued to be practiced, particularly until the New Laws of 1543. The Spanish empire, however was involved in the enslavement people of African origin. Although the Spanish themselves played a very minor role in the Atlantic slave trade compared to other European empires, in absolute terms, the Spanish Empire was a major recipient of African slaves, with around 22% of the Africans delivered to American shores ending up in the Spanish Empire.

The Spanish restricted and outright forbade the enslavement of Native Americans since the early years of the Spanish Empire with the Laws of Burgos of 1512 and the New Laws of 1542. The latter led to the abolition of the Encomienda, private grants of groups of Native Americans to individual Spaniards as well as to Native American nobility. The implementation of the New Laws and liberation of tens of thousands of Native Americas led to a number of rebellions and conspiracies by "Encomenderos" (Encomienda holders) which had to be put down by the Spanish crown. Asian people (chinos) in colonial Mexico had the same status as Native Americans and thus were forbidden to be enslaved by law.

Spain had a precedent for slavery as an institution since it had existed in Spain itself since the times of the Roman Empire. Slavery also existed among Native Americans of both Meso-America and South America. The Crown attempted to limit the bondage of indigenous people, rejecting forms of slavery based on race. Conquistadors regarded indigenous forced labor and tribute as rewards for participation in the conquest and the Crown gave some conquerors encomiendas. The indigenous people held in encomienda were not slaves, but their under paid labor was mandatory and coerced, while they had rights and could take to trial to their managers, and they were "cared for" by the person in whose charge they were placed (encomendado), this might mean offering them the Christian religion and other perceived (by the Spaniards) benefits of Christian civilization. With the collapse of indigenous populations in the Caribbean, where Spaniards created permanent settlements starting in 1493, Spaniards raided other islands and the mainland for indigenous people to enslave on Hispaniola. With the rise of sugar cultivation as an export product in 1810, Spaniards increasingly utilized enslaved African people for labor on commercial plantations. Although plantation slavery in Spanish America was one aspect of slave labor, urban slavery in households, religious institutions, textile workshops (obrajes), and other venues was also important.

Spanish slavery in the Americas diverged from other European powers in that it took on an early abolitionist stance towards Native American slavery. Although it did not directly partake in the trans-Atlantic slave trade, enslaved Black people were sold throughout the Spanish Empire, particularly in Caribbean territories. During the colonial period, Spanish territories were the most extensive and wealthiest in the Americas. Since Spaniards themselves were barred by the Crown from participating in the Atlantic slave trade, the right to export slaves in these territories, known as the Asiento de Negros was a major foreign policy objective of other European powers, sparking numerous European wars such as the War of Spanish Succession and the War of Jenkin's Ear. In the mid-nineteenth century when most countries in the Americas reformed to disallow chattel slavery, Cuba and Puerto Rico – the last two remaining Spanish American colonies – were among the last, followed only by Brazil.

Enslaved people challenged their captivity in ways that ranged from introducing non-European elements into Christianity (syncretism) to mounting alternative societies outside the plantation (slave labour camp) system (Maroons). The first open Black rebellion occurred in Spanish labour camps (plantations) in 1521. Resistance, particularly to the enslavement of indigenous people, also came from Spanish religious and legal ranks. The first speech in the Americas for the universality of human rights and against the abuses of slavery was also given on Hispaniola, a mere nineteen years after the first contact. Resistance to indigenous captivity in the Spanish colonies produced the first modern debates over the legitimacy of slavery. And uniquely in the Spanish American colonies, laws like the New Laws of 1542, were enacted early in the colonial period to protect natives from bondage. To complicate matters further, Spain's haphazard grip on its extensive American dominions and its erratic economy acted to impede the broad and systematic spread of plantations operated by slave labor. Altogether, the struggle against slavery in the Spanish American colonies left a notable tradition of opposition that set the stage for conversations about human rights.

Iberian precedents to New World slavery

Slavery in Spain can be traced to the times of the Greeks, Phoenicians and Romans. Slavery was cross-cultural and multi-ethnic" and, in addition to that, slavery played an important role in the development of the economy for Spain and other countries.

The Romans extensively utilized slavery for labor and slaves' status was specified in the Code of Justinian. With the rise of Christianity, the status of was altered in that Christians were in theory banned from enslaving fellow Christians, but the practice persisted. With the rise of Islam, and the conquest of most of the Iberian peninsula in the eighth century, slavery declined in remaining Iberian Christian kingdoms. At the time of the formation of Al-Andalus, Muslims were prohibited from enslaving fellow believers, but there was a slave trade of non-Muslims in which Muslims and local Jewish merchants traded in Spanish and Eastern European Christian slaves. Mozarabs and Jews were allowed to remain and retain their slaves if they paid a head tax for themselves and half-value for the slaves. However, non-Muslims were prohibited from holding Muslim slaves, and so if one of their slaves converted to Islam, they were required to sell the slave to a Muslim. Mozarabs were later, by the 9th and 10th centuries, permitted to purchase new non-Muslim slaves via the peninsula's established slave trade.

During the reconquista, Christian Spain sought to retake territory lost to Muslims and this lead to changing norms regarding slavery. Though enslavement of Christians was originally permitted, over the period from the 8th to the 11th centuries the Christian kingdoms gradually ceased this practice, limiting their pool of slaves to Muslims from Al-Andalus. Conquered Muslims were enslaved with the justification conversion and acculturation, but Muslim captives were often offered back to their families and communities for cash payments (rescate). The thirteenth-century code of law, the Siete Partidas of Alfonso "the learned" (1252–1284) specified who could be enslaved: those who were captured in just war; offspring of an enslaved mother; those who voluntarily sold themselves into slavery, and specified slaves' good treatment by their masters. At the time it was generally domestic slavery and was a temporary condition of members of outgroups. As well as the formal parameters for slavery, the Siete Partidas also makes a value judgment, stating that it "was the basest and most wretched condition into which anyone could fall because man, who is the freest noble of all God's creatures, becomes thereby in the power of another, who can do with him what he wishes as with any property, whether living or dead."

Lines dividing the non-Christian world between Castile and Portugal: the 1494 Tordesillas meridian (purple) and the 1529 Zaragoza antimeridian (green)

As the Spanish (Castilians) and Portuguese expanded overseas, they conquered and occupied Atlantic islands off the north coast of Africa, including the Canary Islands as well as São Tomé and Madeira where they introduced plantation sugar cultivation. They considered the indigenous populations there more animal than human, supposedly justifying their enslavement. The Canary Islands came under Castilian control, and by the early sixteenth century the indigenous population had largely been decimated and African slave labor replaced indigenously. Multiple West African states were participants in slave raiding and trading, and the slaves the Castilians purchased were considered legitimate slaves. Slave-trading African states accepted a variety of European goods, including firearms, horses, and other desirable goods in exchange for slaves.

Both the Spanish and the Portuguese colonized the Atlantic islands off the coast of Africa, where they engaged in sugar cane production following the model of Mediterranean production. The sugar complex consisted of slave labor for cultivation and processing, with the sugar mill (ingenio) and equipment established with significant investor capital. When plantation slavery was established in Spanish America and Brazil, they replicated the elements of the complex in the New World on a much larger scale.

The Portuguese exploration of the African coast and the division of overseas territories via the Treaty of Tordesillas meant that the African slave trade was held by the Portuguese. However, demand for African slaves as the Spanish established themselves in the Caribbean meant that became part of the Spanish Empire's social mosaic. Black slaves in Spain were overwhelmingly domestic servants, and increasingly became prestigious property for elite Spanish households though at a much smaller scale than the Portuguese. Artisans acquired black slaves and trained them in their trade, increasing the artisans' output.

Another form of forced labor used in the New World with origins in Spain was the encomienda, on the model of the award of the labor to Christian victors over Muslims during the reconquista. This institution of forced labor was initially employed by the Spaniards in the Canary Islands following their conquest, but the Guanche (Canarian) population precipitously declined. The institution as an institution was much more widespread following the Spanish contact and conquests in Mexico and Peru, but the precedents were set prior to 1492.

Prohibition of forced labor of indigenous peoples

An Aztec slave
 
Viceroy Antonio de Mendoza and Tlaxcalan Indians battle with the Caxcanes in the Mixtón War.

Prior to the Spanish colonization of the Americas, slavery was a common institution among some Pre-Columbian indigenous peoples, particularly the Aztecs. The Spanish conquest and settlement in the New World quickly led to large-scale subjugation of indigenous peoples, mainly of the Native Caribbean people, by Columbus on his four voyages. Initially, forced labor represented a means by which the conquistadores mobilized native labor, with disastrous effects on the population. Unlike the Portuguese Crown's support for the slave trade in Africa, los Reyes Católicos (English: Catholic Monarchs) opposed the enslavement of the native peoples in the newly conquered lands on religious grounds. When Columbus returned with indigenous slaves, they ordered the survivors to be returned to their homelands. In 1512, after pressure from Dominican friars, the Laws of Burgos were introduced to protect the rights of the natives in the New World and secure their freedom. The papal bull Sublimus Dei of 1537, to which Spain was committed, also officially banned enslavement of indigenous peoples, but it was rescinded a year after its promulgation.

The other major form of coerced labor in their colonies, the encomienda system, was also abolished, despite the considerable anger this caused in the conquistador group who had expected to hold their grants in perpetuity. It was replaced by the repartimiento system.

After passage of the 1542 New Laws, also known as the New Laws of the Indies for the Good Treatment and Preservation of the Indians, the Spanish greatly restricted the power of the encomienda system, allowed abuse by holders of the labor grants (encomenderos), and officially abolished the enslavement of the native population. However, indigenous people who rebelled against the Spanish could be enslaved, so that following the Mixtón War (1540-42) in northwest Mexico many indigenous slaves were captured and moved elsewhere in Mexico. The statutes of 1573, within the "Ordinances Concerning Discoveries," forbade unauthorized operations against independent Indian peoples. It required appointment of a "protector de indios", an ecclesiastical representative who acted as the protector of the Indians and represented them in formal litigation. Later in the 16th century, in Peru, thousands of indigenous men were forced to hard work as underground miners in the silver mines of Potosí, by means of the continuation of the pre-Hispanic Inca mita tradition.

Reinstatement of slavery for Mapuche rebels

King Philip III inherited a difficult situation in Chile, where the Arauco War raged and the local Mapuche succeeded in razing seven Spanish cities (1598–1604). An estimate by Alonso González de Nájera put the toll at 3000 Spanish settlers killed and 500 Spanish women taken into captivity by Mapuche. In retaliation the proscription against enslaving Indians captured in war was lifted by Philip in 1608. This decree was abused when Spanish settlers in Chiloé Archipelago used it to launch slave raids against groups such as the Chono of northwestern Patagonia who had never been under Spanish rule and never rebelled. The Real Audiencia of Santiago opined in the 1650s that slavery of Mapuches was one of the reasons for constant state of war between the Spanish and the Mapuche. Slavery for Mapuches "caught in war" was abolished in 1683 after decades of legal attempts by the Spanish Crown to suppress it.

Africans in the early colonial period

Spanish conquistadors in Mexico led by Hernán Cortés. The Spaniards are accompanied by native porters, Malinche, and a black man (holding the horse). Codex Azcatitlan.

When Spain first enslaved Native Americans on Hispaniola, and then replaced them with captive Africans, it established slave labor as the basis for colonial sugar production. It was believed by Europeans that Africans had developed immunities to European diseases, and would not be as susceptible to fall ill as the Native Americans because they had not been exposed to the pathogens yet. In 1501, Spanish colonists began importing enslaved Africans from the Iberian Peninsula to their Santo Domingo colony on the island of Hispaniola. These first Africans, who had been enslaved in Europe before crossing the Atlantic, may have spoken Spanish and perhaps were even Christians. About 17 of them started in the copper mines, and about a hundred were sent to extract gold. As Old World diseases decimated Caribbean indigenous populations in the first decades of the 1500s, enslaved blacks from Africa (bozales) gradually replaced their labor, but they also mingled and joined in flights to freedom, creating mixed-race maroon communities in all the islands where Europeans had established chattel slavery.

Spanish colonist turned Dominican friar Bartolomé de las Casas (1484–1566) observed and recorded the effects of enslavement on the Native populations. Initially he sought to protect the indigenous from enslavement by advocating and participating in the African slavetrade. He later argued that enslavement of both indigenous and Africans was wrong, violating their human rights. Las Casas campaigned for protections of the indigenous, especially crown limits on the exploitation of the encomienda, helping to bring about the 1542 New Laws.

In Spanish Florida and farther north, the first African slaves arrived in 1526 with Lucas Vázquez de Ayllón's establishment of San Miguel de Gualdape on the current Georgia coast. They rebelled and lived with indigenous people, destroying the colony in less than 2 months. More slaves arrived in Florida in 1539 with Hernando de Soto, and in the 1565 founding of St. Augustine, Florida. Native Americans were also enslaved in Florida by the encomienda system. Slaves escaping to Florida from the colony of Georgia were freed by Carlos II's proclamation November 7, 1693 if the slaves were willing to convert to Catholicism, and it became a place of refuge for slaves fleeing the Thirteen Colonies.

In this early period, enslaved African men were often labor bosses, overseeing indigenous labor. Franciscan Toribio de Benavente Motolinia (1482-1568), one of the First Twelve Franciscans to arrive in Mexico in 1524, considered blacks the Fourth Plague on Mexican Indians. He wrote "In the first years these black overseers were so absolute in their maltreatment of the Indians, over-loading them, sending them far from their land and giving them many other tasks that many Indians died because of them and at their hands, which is the worst feature of the situation." In Yucatan, there were regulations attempting to prevent blacks presence in indigenous communities. In Mexico City in 1537, a number of blacks were accused of rebellion. They were executed in the main plaza (zócalo) by hanging, an event recorded in an indigenous pictorial and alphabetic manuscript.

Demand for African slaves was high and the slave trade was controlled by the Portuguese, who set up trading posts on the west coast of Africa. Spanish colonists purchased them directly from Portuguese traders, who in turn purchased them from African traders on the Atlantic coast. With the increased dependency on enslaved Africans and with the Spanish crown opposed to enslavement of indigenous, except in the case of rebellion, slavery became associated with race and racial hierarchy, with Europeans hardening their concepts of racial ideologies. These were buttressed by prior ideologies of differentiation as that of the limpieza de sangre (en: purity of blood), which in Spain referred to individuals without the perceived taint of Jewish or Muslim ancestry. However, in Spanish America, purity of blood came to mean a person free of any African ancestry.

In the vocabulary of the time, each enslaved African who arrived at the Americas was called "Pieza de Indias" (en: a piece of the Indies). The crown issued licenses asientos, to merchants to specifically trade slaves, regulating the trade. During the 16th century, the Spanish colonies were the most important customers of the Atlantic slave trade, claiming several thousands in sales, but other European colonies soon dwarfed these numbers when their demand for enslaved workers began to drive the slave market to unprecedented levels.

Some of the first black people in the Americas were "Atlantic Creoles", as the charter generation is described by the American historian Ira Berlin. Mixed-race men of African and Portuguese/Spanish descent, some slaves and others free, sailed with Iberian ships and worked in the ports of Spain and Portugal; some were born in Europe, others in African ports as sons of Portuguese trade workers and African women. African slaves were also taken to Portugal, where they married local women. The mixed-race men often grew up bilingual, making them useful as interpreters in African and Iberian ports.

Some famous black Spanish soldiers in the first stages of the Spanish conquest of America were Juan Valiente and Juan Beltrán in Chile, Juan Garrido (credited with the first harvesting of wheat planted in New Spain) and Sebastián Toral in Mexico, Juan Bardales in Honduras and Panama, and Juan García [es] in Peru.

The first known and recorded Christian marriage anywhere in the continental United States was an interracial union between a free black Spanish woman from Jerez de la Frontera and a Spanish settler from Segovia who met in Seville and embarked together as a couple to the New World. This marriage took place in 1565 in the Spanish settlement of St. Augustine, Florida.

Estevanico, recorded as a black slave from Morocco, survived the disastrous Narváez expedition from 1527 to 1536 when most of the men died. After the ships, horses, equipment and finally most of the men were lost, with three other survivors, Estevanico spent six years traveling overland from present-day Texas to Sinaloa, and finally reaching the Spanish settlement at Mexico City. He learned several Native American languages in the process. He went on to serve as a well-respected guide. Later, while leading an expedition in what is now New Mexico in search of the Seven Cities of Gold, he was killed in a dispute with the Zuñi local people.

Black slavery in the late colonial period

The population of slaves in Cuba received a large boost when the British captured Havana during the Seven Years' War, and imported 10,000 slaves from their other colonies in the West Indies to work on newly established agricultural plantations. These slaves were left behind when the British returned Havana to the Spanish as part of the 1763 Treaty of Paris, and form a significant part of the Afro-Cuban population today.

While historians have studied the production of sugar on plantations by enslaved workers in nineteenth-century Cuba, they have sometimes overlooked the crucial role of the Spanish state before the 1760s. Cuba ultimately developed two distinct but interrelated sources using enslaved labor, which converged at the end of the eighteenth century. The first of these sectors was urban and was directed in large measure by the needs of the Spanish colonial state, reaching its height in the 1760s. As of 1778, it was reported by Thomas Kitchin that "about 52,000 slaves" were being brought from Africa to the West Indies by Europeans, with approximately 4,000 being brought by the Spanish.

The second sector, which flourished after 1790, was rural and was directed by private slaveholders/planters involved in the production of export agricultural commodities, especially sugar. After 1763, the scale and urgency of defense projects led the state to deploy many of its enslaved workers in ways that were to anticipate the intense work regimes on sugar plantations in the nineteenth century. Another important group of workers enslaved by the Spanish colonial state in the late eighteenth century were the king's laborers, who worked on the city's fortifications.

The Spanish colonies were late to exploit slave labor in the production of sugarcane, particularly on Cuba. The Spanish colonies in the Caribbean were among the last to abolish slavery. While the British abolished slavery by 1833, Spain abolished slavery in Puerto Rico in 1873. On the mainland of colonies, Spain ended African slavery in the eighteenth century. Peru was one of the countries that revived the institution for some decades after declaring independence from Spain in the early 19th century.

Fugitive slaves in Spanish territories

On May 29, 1680 the Spanish crown decreed that slaves escaping to Spanish territories from Barlovento, Martinique, San Vicente and Granada in the Lesser Antilles would be free if they accepted Catholicism. On September 3, 1680 and June 1, 1685 the crown issued similar decrees for escaping French slaves. On November 7, 1693 King Carlos II issued a decree freeing all slaves escaping from the English colonies who accepted Catholicism. There were similar decrees October 29, 1733, March 11 and November 11, 1740, and September 24, 1850 in the Buen Retiro by Ferdinand VI and the Royal Decree of October 21, 1753.

Since 1687, Spanish Florida attracted numerous African slaves who escaped from slavery in the Thirteen Colonies. Since 1623 the official Spanish policy had been that all slaves who touched Spanish soil and asked for refuge could become free Spanish citizens, and would be assisted in establishing their own workshops if they had a trade or given a grant of land to cultivate if they were farmers. In exchange they would be required to convert to Catholicism and serve for a number of years in the Spanish militia. Most were settled in a community called Gracia Real de Santa Teresa de Mose, the first settlement of free African's in North America. The enslaved African Francisco Menéndez escaped from South Carolina and traveled to St. Augustine, Florida, where he became the leader of the settlers at Mose and commander of the black militia company there from 1726 until sometime after 1742.

The former slaves also found refuge among the Creek and Seminole, Native Americans who had established settlements in Florida at the invitation of the Spanish government. In 1771, Governor of Florida John Moultrie wrote to the Board of Trade, "It has been a practice for a good while past, for negroes to run away from their Masters, and get into the Indian towns, from whence it proved very difficult to get them back." When colonial officials asked the Native Americans to return the fugitive slaves, they replied that they had "merely given hungry people food, and invited the slaveholders to catch the runaways themselves."

After the American Revolutionary War, slaves from the state of Georgia and the Low Country of South Carolina escaped to Florida. The U.S. Army led increasingly frequent incursions into Spanish territory, including the 1817–1818 campaign by Andrew Jackson that became known as the First Seminole War. The United States afterwards effectively controlled East Florida (from the Atlantic to the Appalachicola River). According to Secretary of State John Quincy Adams, the US had to take action there because Florida had become "a derelict open to the occupancy of every enemy, civilized or savage, of the United States, and serving no other earthly purpose than as a post of annoyance to them.". Spain requested British intervention, but London declined to assist Spain in the negotiations. Some of President James Monroe's cabinet demanded Jackson's immediate dismissal, but Adams realized that Jackson's actions had put the U.S. in a favorable diplomatic position. Adams negotiated very favorable terms.

As Florida had become a burden to Spain, which could not afford to send settlers or garrisons, the Crown decided to cede the territory to the United States. It accomplished this through the Adams–Onís Treaty in 1819, effective 1821.

Ending of slavery

Support for abolitionism rose in Great Britain. Slavery in France's Caribbean colonies was abolished by Revolutionary decree in 1794, (slavery in Metropolitan France was abolished in 1315 by Louis X) but was restored under Napoleon I in 1802. Slaves in Saint-Domingue revolted in response and became independent following a brutal conflict. The victorious former slaves founded the republic of Haiti in 1804.

Later slave revolts were arguably part of the upsurge of liberal and democratic values centered on individual rights and liberties which came in the aftermath of the Enlightenment and the French Revolution in Europe. As emancipation became more of a concrete reality, the slaves' concept of freedom changed. No longer did they seek to overthrow the whites and re-establish carbon-copy African societies as they had done during the earlier rebellions; the vast majority of slaves were creole, native born where they lived, and envisaged their freedom within the established framework of the existing society.

On March 22, 1873, Spain abolished slavery in Puerto Rico. The owners were compensated.

The Spanish American wars of independence emancipated most of the overseas territories of Spain; in the Americas, various nations emerged from these wars. The wars were influenced by the ideas of the Age of Enlightenment and economic affairs, which also led to the reduction and ending of feudalism. For example, in Mexico on 6 December 1810, Miguel Hidalgo, leader of the independence movement, issued a decree abolishing slavery, threatening those who did not comply with death. In South America Simon Bolivar abolished slavery in the lands that he conquered. However, it was not a unified process. Some countries, including Peru and Ecuador, reintroduced slavery for some time after achieving independence.

In the treaty of 1814, King Ferdinand of Spain promised to consider means for abolishing the slave trade. In the treaty of September 23, 1817, with Great Britain, the Spanish Crown said that "having never lost sight of a matter so interesting to him and being desirous of hastening the moment of its attainment, he has determined to co-operate with His Britannic Majesty in adopting the cause of humanity." The king bound himself "that the slave trade will be abolished in all the dominions of Spain, May 30, 1820, and that after that date it shall not be lawful for any subject of the crown of Spain to buy slaves or carry on the slave trade upon any part of the coast of Africa." The date of final suppression was October 30. The subjects of the king of Spain were forbidden to carry slaves for any one outside the Spanish dominions, or to use the flag to cover such dealings.

The Assembly of Year XIII (1813) of the United Provinces of the Río de la Plata declared the freedom of wombs. It did not end slavery completely, but emancipated the children of slaves. Many slaves gained emancipation by joining the armies, either against royalists during the War of Independence, or during the later Civil Wars. For example, the Argentine Confederation ended slavery definitely with the sanction of the Argentine Constitution of 1853.

Behavioral contagion

From Wikipedia, the free encyclopedia

Behavioral contagion is a form of social contagion involving the spread of behavior through a group. It refers to the propensity for a person to copy a certain behavior of others who are either in the vicinity, or whom they have been exposed to. The term was originally used by Gustave Le Bon in his 1895 work The Crowd: A Study of the Popular Mind to explain undesirable aspects of behavior of people in crowds. In the digital age, behavioral contagion is also concerned with the spread of online behavior and information. A variety of behavioral contagion mechanisms were incorporated in models of collective human behavior.

Behavioral contagion has been attributed to a variety of different factors. Often it is distinguished from collective behavior that arises from a direct attempt at social influence. A prominent theory involves the reduction of restraints, put forth by Fritz Redl in 1949 and analyzed in depth by Ladd Wheeler in 1966. Social psychologists acknowledge a number of other factors, which influence the likelihood of behavioral contagion occurring, such as deindividuation (Festinger, Pepitone, & Newcomb, 1952) and the emergence of social norms (Turner, 1964). In 1980, Freedman et al. have focused on the effects of physical factors on contagion, in particular, density and number.

J. O. Ogunlade (1979, p. 205) describes behavioral contagion as a "spontaneous, unsolicited and uncritical imitation of another's behavior" that occurs when certain variables are met: a) the observer and the model share a similar situation or mood (this is one way behavioral contagion can be readily applied to mob psychology); b) the model's behavior encourages the observer to review his condition and to change it; c) the model's behavior would assist the observer to resolve a conflict by reducing restraints, if copied; and d) the model is assumed to be a positive reference individual.

Types of contagion

Social contagion can occur through threshold models that assume that an individual needs to be convinced by a fraction of their social contacts above a given threshold to adopt a novel behaviour. Therefore, the number of exposures will not increase chances of contagion unless the number of source exposures pass a certain threshold. The threshold value can divide contagion processes to two types: 1) Simple contagion and 2) Complex contagion.

Simple contagion

The individual needs only one person displaying the novel behaviour to copy. For instance, cars travel in groups on a two-lane highway since the car in each cluster travels at a slower speed than the car behind it. This relative speed spreads through other cars who slow down to match the speed of the car in front.

Complex contagion

The individual needs to be in contact with two or more sources exhibiting the novel behaviour. This is when copying behaviours needs reinforcement or encouragement from multiple sources. Multiple sources, especially close friends, can make imitation legitimate, credible and worthwhile due to collective effort put in. Examples of complex contagions can be copying risky behaviour or joining social movements and riots.

Factors

Strength of ties

Social contagion in simple contagion models occurs most effectively through 'weak' and 'long' ties between social contacts. A 'weak' tie between two people means they do not interact as frequently and do not influence each other as close friends. However, a relationally 'weak' tie is structurally strong if it is 'long' because it connects socially distant people, showing greater outreach than a relationally 'strong' tie. These 'long' ties allow the flow of new information increasing rate of transmission that relationally strong ties cannot do. Even though close friends can strongly influence each other, they will not help each other learn about new opportunities, ideas or behaviours in socially distant settings if they all know the same things. Few 'weak' and 'long' ties can help spread information quickly between two socially distant strong networks of people. 'Strong' ties within those networks can help spread information amongst the peers.

On the other hand, complex social contagion processes require multiple sources of influence. This is not possible with few 'weak' ties: they need to be long and multiple in number to increase the probability of imitation between socially distant networks.

Structural equivalence

However, social contagion can also occur in the absence of any ties during competition. This happens when two people are structurally equivalent i.e., they occupy the same position in a social network and have the same pattern of relationships with the same people. For instance, two students publishing the same kind of research under the same professor are structurally equivalent. The more similar their relations are with other people i.e. the more substitutable they are with one another, the more they will copy what the other is doing, if it makes them look better, to stay ahead of competition.

Reduction of restraints

Behavioral contagion is a result of the reduction of fear or restraints – aspects of a group or situation which prevent certain behaviors from being performed. Restraints are typically group-derived, meaning that the "observer", the individual wishing to perform a certain behavior, is constrained by the fear of rejection by the group, who would view this behavior as a "lack of impulse control".

An individual (the "observer") wants to perform some behavior, but that behavior would violate the unspoken and accepted rules of the group or situation they are in; these rules are the restraints preventing the observer from performing that action. Once the restraints are broken or reduced the observer is then "free" to perform the behavior; this is achieved by the "intervention" of the model. The model is another individual, in the same group or situation as the observer, who performs the behavior which the observer wished to perform. Stephenson and Fielding (1971) describe this effect as "[Once] one member of a gathering has performed a commonly desired action, the payoffs for similar action or nonaction are materially altered. ... [The] initiator, by his action, establishes an inequitable advantage over the other members of the gathering which they may proceed to nullify by following his example."

Density and number

Density refers to the amount of space available to a person – high density meaning there is less space per person – and number refers to the size of the group. Freedman (1975) put forth the intensification theory, which posits that high density makes the other people in a group more salient features of the environment, this magnifying the individual's reaction to them. Research has shown that high density does in fact increase the likelihood of contagion (Freedman, 1975; Freedman, Birsky, & Cavoukian, 1980). Number also has an effect on contagion, but to a lesser degree than density.

Local trend imitation

However, the probability that an individual will copy a behaviour can also decrease with higher density and number of neighbours. For instance, a person might praise and go to a restaurant with good food based on others’ recommendations but avoid it when it becomes over-crowded. This depicts the local trend imitation phenomenon i.e. the adoption probability first increases with increase in number of adopted neighbours and then decreases.

Identity of the model

Stephenson and Fielding (1971) state that the identity of the model is a factor that influences contagion (p. 81). Depending on the behavior, sex of the model may be a factor in the contagion of that behavior being performed by other individuals – particularly in instances of adult models performing aggressive behavior in the presence of children-observers (Bandura, Ross, & Ross, 1963) {Imitation of film-mediated aggressive models}. In this particular series of experiments – Albert Bandura's Bobo doll experiments from 1961 and 1963 – where the behavior of children was studied after the children watched an adult model punching a bobo doll and the model received a reward, a punishment, or there were no consequences, the analyses revealed that the male model influenced the participants' behavior to a greater extent than did the female model; this was true for both the aggressive and the nonaggressive male models (p. 581).

Dominant leaders

Aggressive behaviour or using coercion, fear or intimidation to imitate a behaviour is known as dominance. People are likely to follow dominant leaders to avoid the cost of punishment. However, such behaviour is more influential amongst children rather than adults: coercive children are thought to be more likeable whereas coercive adults are less likeable and, hence, influential.

Prestigious influencers

While dominant behaviour is displayed in the animal kingdom as well, prestigious behaviour is unique to humans. Unlike animals, we understand the intentions behind someone's actions rather than just being able to copy their movements precisely. This is important since it is easier to learn from the best models rather than learning by ourselves: We might know which behaviour contributes to someone's success at mastering a skill. Hence, we look to see who everyone else is copying i.e. we tend to copy prestigious individuals. Prestigious people enjoy a high degree of influence and respect and are generally the people with the most information.

Ordinary people

A study done on the rate of information transmission via retweets on Twitter found that popular people i.e. people with a large following, are 'inefficient hubs' in spreading concepts. The more followers someone has, the more overloaded they are with information and lower the chances that they will retweet a particular message due to limited attention. Hence, rate of social contagion slows down.

Rather, social contagion can amplify amongst 'ordinary' users with low following if they are closely connected in a peer network. People are more likely to retweet messages by close friends to facilitate social bonding. Peers also have higher similar interests and are more influenced by each other than an 'ordinary' and 'popular' user who do not have mutual ties. Hence, social contagion can occur efficiently amongst tight community structures, in the absence of prestigious and dominant leaders.

Media

Mass media can greatly influence people's opinions and amplify social contagion by reporting stories from socially distant and unconnected networks. They can help to turn minority opinions into the popular opinion, independent of the degree of connectivity between people.

Moreover, Bandura (1977) showed that children can learn and imitate fictitious characters on television.

Personality of the observer

Ogunlade (1979) found that extroverts, who are described as impulsive and sociable individuals, are more likely to be susceptible to contagion than introverted individuals, who are described as reserved and emotionally controlled.

Social norms

Gino, Ayal and Ariely (2009) state that an important factor influencing contagion is the degree to which the observer identifies with the others of the group (p. 394). When identification with the rest of the group is strong, the behaviors of the others will have a larger influence.

However, high homophily or the likelihood of being connected to others with similar interests, can lead to both minority and majority groups overestimating their sizes and vice versa. This can cause people to falsely predict the frequency of their behaviour in the real world since they estimate based on their personal networks. When people overestimate the frequency of a particular behaviour, they may think that they are following social norms and, hence, are less willing to change. Encouraging interactions within heterophilic rather than homophilic social networks can facilitate social contagion more.

Similarities and differences with other types of social influence

Contagion is only one of a myriad of types of social influence.

Conformity / social pressures

Conformity is a type of social influence that is very similar to contagion. It is almost identical to another type of social influence, "pressures toward uniformity" (social pressures) (Festinger, 1954), which differ only in the research techniques they are associated with (Wheeler, 1966, p. 182).

Both conformity and contagion involve some sort of conflict, but differ in the roles other individuals play in that conflict. In conformity, the other individuals of the group try to pressure the observer into performing a behavior; the model then performs some other behavior in the vicinity of the observer. This results in the observer creating restraints against the pressured behavior and a conflict between the pressured behavior and the behavior performed by the model. In the end, the observer either performs the model's behavior his-/herself, rejects the model, or pressures the model to perform the original pressured behavior (Wheeler, Table 1). In contagion, the model's behavior results in the removing of restraints and the resolving of the conflict, while in conformity, the model's behavior results in the creation of restraints and of the conflict.

Social facilitation

Social facilitation, another type of social influence, is distinguished from contagion, as well as from conformity and social pressures, by the lack of any marked conflict. It is said to occur when the performance of an instinctive pattern of behavior by an individual acts as a releaser for the same behavior in others, and so initiates the same line of action in the whole group (Thorpe, 1956, p. 120). Bandura and Walters (1963, p. 79), give the example of an adult, who has lost the unique aspects of the dialect of the region where they were raised, returns for a visit and "regains" those previously lost patterns of speech. Starch (1911) referred to this phenomenon as an "unintentional or unconscious imitation".

Imitation

Imitation is different from contagion in that it is learned via reward and punishment and is generalized across situations. Imitation can also be a generic term for contagion, conformity, social pressures, and social facilitation.

(Wheeler, 1966, Table 1) Dynamics of selected influence processes

Stages in influence process Behavioral contagion Social pressures and conformity Social facilitation
Observer's initial conditions Instigated to BN*. Internal restraints against BN. Instigated to BP*. No restraints. No restraints against BN or BP. No instigation to BN or BP.
Model's behavior Model performs BN. Model performs BN. Model performs BN.
Hypothetical processes Reduction of model's restraints against BN. Fear reduction. Creation of restraints against BP. Conflict between BN and BP. Cognitive-behavioral chaining, CS* elicits CR*, inertia overcome.
Observer's behavior Observer performs BN. Observer performs BN (or rejects model or induces model to perform BP). Observer performs BN.
  • BN = initial behavior
  • BP = pressured behavior
  • CS = conditioned stimulus
  • CR = conditioned response

Competition contagion on non-competitors

While behavioral contagion is largely about how people might be affected by observations of the expressions or behavior of others, research has also found contagion in the context of a competition where mere awareness of an ongoing competition can have an influence on noncompetitors' task performance, without any information about the actual behavior of the competitors.

Research

Effects of group pressure

Behavioral contagion, largely discussed in the behaviors of crowds, and closely related to emotional contagion, plays a large role in gatherings of two or more people. In the original Milgram experiment on obedience, for example, where participants, who were in a room with only the experimenter, were ordered to administer increasingly more severe electrical shocks as punishment to a person in another room (from here on referred to as the "victim"), the conflict or social restraint experienced by the participants was the obligation to not disobey the experimenter – even when shocking the victim to the highest shock level given, a behavior which the participants saw as opposing their personal and social ideals (Milgram, 1965, p. 129).

Milgram also conducted two other experiments, replications of his original obedience experiment, with the intent being to analyze the effect of group behavior on participants: instead of the subject being alone with the experimenter, two confederates were utilized. In the first of the two experiments, "Groups for Disobedience", the confederates defied the experimenter and refused to punish the victim (p. 130). This produced a significant effect on the obedience of the participants: in the original experiment, 26 of the 40 participants administered the maximum shock; in the disobedient groups experiment, only 4 of 40 participants administered the highest level of voltage (Table 1). Despite this high correlation between shock level administered and the obedience of the group in the disobedient groups experiment, there was no significant correlation for the second of the replicated experiments: "Obedient Groups", where the confederates did not disobey the experimenter and, when the participant voiced angst regarding the experiment and wished to stop administering volts to the victim, the confederates voiced their disapproval (p. 133). Milgram concludes the study by remarking that "the insertion of group pressure in a direction opposite that of the experimenter's commands produces a powerful shift toward the group. Changing the group movement does not yield a comparable shift in the [participant's] performance. The group success in one case and failure in another can be traced directly to the configuration of motive and social forces operative in the starting situation." That is, if the group's attitudes are similar to or compatible with the participant's/observer's, there is a greater likelihood that the participant/observer will join with the group (p. 134).

Overweight and obesity

Network phenomena are relevant to obesity, which appears to spread through social ties. Teenagers of US Army families assigned to counties with higher obesity rates were more likely to become overweight or obese in a 2018 study. This effect could not be explained by self-selection (homophily) or shared built environments and is attributed to social contagion.

Friday, February 25, 2022

Synthetic fuel

From Wikipedia, the free encyclopedia
 
Side-by-side comparison of FT synthetic fuel and conventional fuel. The synthetic fuel is extremely clear because of the near-total absence of sulfur and aromatics.

Synthetic fuel or synfuel is a liquid fuel, or sometimes gaseous fuel, obtained from either syngas, a mixture of carbon monoxide and hydrogen, or a mixture of carbon dioxide and hydrogen. The syngas could be derived from gasification of solid feedstocks such as coal or biomass or by reforming of natural gas. Alternatively a mixture of carbon dioxide from the atmosphere and green hydrogen could be used for an almost climate neutral production of synthetic fuels.

Common ways for refining synthetic fuels include the Fischer–Tropsch conversion, methanol to gasoline conversion, or direct coal liquefaction.

As of July 2019, worldwide commercial synthetic fuels production capacity was over 240,000 barrels per day (38,000 m3/d), with numerous new projects in construction or development, such as Carbon Engineering.

Classification and principles

The term 'synthetic fuel' or 'synfuel' has several different meanings and it may include different types of fuels. More traditional definitions, such as the definition given by the International Energy Agency, define 'synthetic fuel' or 'synfuel' as any liquid fuel obtained from coal or natural gas. In its Annual Energy Outlook 2006, the Energy Information Administration defines synthetic fuels as fuels produced from coal, natural gas, or biomass feedstocks through chemical conversion into synthetic crude and/or synthetic liquid products. A number of synthetic fuel's definitions include fuels produced from biomass, and industrial and municipal waste. The definition of synthetic fuel also allows oil sands and oil shale as synthetic fuel sources, and in addition to liquid fuels, synthesized gaseous fuels are also considered to be synthetic fuels: in his 'Synthetic fuels handbook' petrochemist James G. Speight included liquid and gaseous fuels as well as clean solid fuels produced by conversion of coal, oil shale or tar sands, and various forms of biomass, although he admits that in the context of substitutes for petroleum-based fuels it has even wider meaning. Depending on the context, methanol, ethanol and hydrogen may also be included.

Synthetic fuels are produced by the chemical process of conversion. Conversion methods could be direct conversion into liquid transportation fuels, or indirect conversion, in which the source substance is converted initially into syngas which then goes through additional conversion process to become liquid fuels. Basic conversion methods include carbonization and pyrolysis, hydrogenation, and thermal dissolution.

History

Ruins of the German synthetic petrol plant (Hydrierwerke Pölitz AG) in Police, Poland
 

The process of direct conversion of coal to synthetic fuel originally developed in Germany. Friedrich Bergius developed the Bergius process, which received a patent in 1913. Karl Goldschmidt invited Bergius to build an industrial plant at his factory, the Th. Goldschmidt AG (part of Evonik Industries from 2007), in 1914. Production began in 1919.

Indirect coal conversion (where coal is gasified and then converted to synthetic fuels) was also developed in Germany - by Franz Fischer and Hans Tropsch in 1923. During World War II (1939-1945), Germany used synthetic-oil manufacturing (German: Kohleverflüssigung) to produce substitute (Ersatz) oil products by using the Bergius process (from coal), the Fischer–Tropsch process (water gas), and other methods (Zeitz used the TTH and MTH processes). In 1931 the British Department of Scientific and Industrial Research located in Greenwich, England, set up a small facility where hydrogen gas was combined with coal at extremely high pressures to make a synthetic fuel.

The Bergius process plants became Nazi Germany's primary source of high-grade aviation gasoline, synthetic oil, synthetic rubber, synthetic methanol, synthetic ammonia, and nitric acid. Nearly one third of the Bergius production came from plants in Pölitz (Polish: Police) and Leuna, with 1/3 more in five other plants (Ludwigshafen had a much smaller Bergius plant which improved "gasoline quality by dehydrogenation" using the DHD process).

Synthetic fuel grades included "T.L. [jet] fuel", "first quality aviation gasoline", "aviation base gasoline", and "gasoline - middle oil"; and "producer gas" and diesel were synthesized for fuel as well (converted armored tanks, for example, used producer gas). By early 1944 German synthetic-fuel production had reached more than 124,000 barrels per day (19,700 m3/d) from 25 plants, including 10 in the Ruhr Area. In 1937 the four central Germany lignite coal plants at Böhlen, Leuna, Magdeburg/Rothensee, and Zeitz, along with the Ruhr Area bituminous coal plant at Scholven/Buer, produced 4.8 million barrels (760×103 m3) of fuel. Four new hydrogenation plants (German: Hydrierwerke) were subsequently erected at Bottrop-Welheim (which used "Bituminous coal tar pitch"), Gelsenkirchen (Nordstern), Pölitz, and, at 200,000 tons/yr Wesseling. Nordstern and Pölitz/Stettin used bituminous coal, as did the new Blechhammer plants. Heydebreck synthesized food oil, which was tested on concentration camp prisoners. After Allied bombing of Germany's synthetic-fuel production plants (especially in May to June 1944), the Geilenberg Special Staff used 350,000 mostly foreign forced-laborers to reconstruct the bombed synthetic-oil plants, and, in an emergency decentralization program, the Mineralölsicherungsplan [de] (1944-1945), to build 7 underground hydrogenation plants with bombing protection (none were completed). (Planners had rejected an earlier such proposal, expecting that Axis forces would win the war before the bunkers would be completed.) In July 1944 the "Cuckoo" project underground synthetic-oil plant (800,000 m2) was being "carved out of the Himmelsburg" north of the Mittelwerk, but the plant remained unfinished at the end of World War II. Production of synthetic fuel became even more vital for Nazi Germany when Soviet Red Army forces occupied the Ploiești oilfields in Romania on 24 August 1944, denying Germany access to its most important natural oil source.

Indirect Fischer–Tropsch ("FT") technologies were brought to the United States after World War II, and a 7,000 barrels per day (1,100 m3/d) plant was designed by HRI and built in Brownsville, Texas. The plant represented the first commercial use of high-temperature Fischer–Tropsch conversion. It operated from 1950 to 1955, when it was shut down after the price of oil dropped due to enhanced production and huge discoveries in the Middle East.

In 1949 the U.S. Bureau of Mines built and operated a demonstration plant for converting coal to gasoline in Louisiana, Missouri. Direct coal conversion plants were also developed in the US after World War II, including a 3 TPD plant in Lawrenceville, New Jersey, and a 250-600 TPD Plant in Catlettsburg, Kentucky.

In later decades the Republic of South Africa established a state oil company including a large synthetic fuel establishment.

Processes

The numerous processes that can be used to produce synthetic fuels broadly fall into three categories: Indirect, Direct, and Biofuel processes.

This is a listing of many of the different technologies used in 2009 for synthetic fuel production. Please note that although this list was compiled for coal to liquids technologies, many of the same processes can also be used with biomass or natural gas feedstocks.

Indirect conversion

Indirect conversion has the widest deployment worldwide, with global production totaling around 260,000 barrels per day (41,000 m3/d), and many additional projects under active development.

Indirect conversion broadly refers to a process in which biomass, coal, or natural gas is converted to a mix of hydrogen and carbon monoxide known as syngas either through gasification or steam methane reforming, and that syngas is processed into a liquid transportation fuel using one of a number of different conversion techniques depending on the desired end product.

Indirect conversion synthetic fuels processes.jpg

The primary technologies that produce synthetic fuel from syngas are Fischer–Tropsch synthesis and the Mobil process (also known as Methanol-To-Gasoline, or MTG). In the Fischer–Tropsch process syngas reacts in the presence of a catalyst, transforming into liquid products (primarily diesel fuel and jet fuel) and potentially waxes (depending on the FT process employed).

The process of producing synfuels through indirect conversion is often referred to as coal-to-liquids (CTL), gas-to-liquids (GTL) or biomass-to-liquids (BTL), depending on the initial feedstock. At least three projects (Ohio River Clean Fuels, Illinois Clean Fuels, and Rentech Natchez) are combining coal and biomass feedstocks, creating hybrid-feedstock synthetic fuels known as Coal and Biomass To Liquids (CBTL).

Indirect conversion process technologies can also be used to produce hydrogen, potentially for use in fuel cell vehicles, either as slipstream co-product, or as a primary output.

Direct conversion

Direct conversion refers to processes in which coal or biomass feedstocks are converted directly into intermediate or final products, avoiding the conversion to syngas via gasification. Direct conversion processes can be broadly broken up into two different methods: Pyrolysis and carbonization, and hydrogenation.

Hydrogenation processes

One of the main methods of direct conversion of coal to liquids by hydrogenation process is the Bergius process. In this process, coal is liquefied by heating in the presence of hydrogen gas (hydrogenation). Dry coal is mixed with heavy oil recycled from the process. Catalysts are typically added to the mixture. The reaction occurs at between 400 °C (752 °F) to 500 °C (932 °F) and 20 to 70 MPa hydrogen pressure. The reaction can be summarized as follows:

After World War I several plants were built in Germany; these plants were extensively used during World War II to supply Germany with fuel and lubricants.

The Kohleoel Process, developed in Germany by Ruhrkohle and VEBA, was used in the demonstration plant with the capacity of 200 ton of lignite per day, built in Bottrop, Germany. This plant operated from 1981 to 1987. In this process, coal is mixed with a recycle solvent and iron catalyst. After preheating and pressurizing, H2 is added. The process takes place in tubular reactor at the pressure of 300 bar and at the temperature of 470 °C (880 °F). This process was also explored by SASOL in South Africa.

In 1970-1980s, Japanese companies Nippon Kokan, Sumitomo Metal Industries and Mitsubishi Heavy Industries developed the NEDOL process. In this process, a mixture of coal and recycled solvent is heated in the presence of iron-based catalyst and H2. The reaction takes place in tubular reactor at temperature between 430 °C (810 °F) and 465 °C (870 °F) at the pressure 150-200 bar. The produced oil has low quality and requires intensive upgrading. H-Coal process, developed by Hydrocarbon Research, Inc., in 1963, mixes pulverized coal with recycled liquids, hydrogen and catalyst in the ebullated bed reactor. Advantages of this process are that dissolution and oil upgrading are taking place in the single reactor, products have high H:C ratio, and a fast reaction time, while the main disadvantages are high gas yield, high hydrogen consumption, and limitation of oil usage only as a boiler oil because of impurities.

The SRC-I and SRC-II (Solvent Refined Coal) processes were developed by Gulf Oil and implemented as pilot plants in the United States in the 1960s and 1970s. The Nuclear Utility Services Corporation developed hydrogenation process which was patented by Wilburn C. Schroeder in 1976. The process involved dried, pulverized coal mixed with roughly 1wt% molybdenum catalysts. Hydrogenation occurred by use of high temperature and pressure syngas produced in a separate gasifier. The process ultimately yielded a synthetic crude product, Naphtha, a limited amount of C3/C4 gas, light-medium weight liquids (C5-C10) suitable for use as fuels, small amounts of NH3 and significant amounts of CO2. Other single-stage hydrogenation processes are the Exxon donor solvent process, the Imhausen High-pressure Process, and the Conoco Zinc Chloride Process.

A number of two-stage direct liquefaction processes have been developed. After the 1980s only the Catalytic Two-stage Liquefaction Process, modified from the H-Coal Process; the Liquid Solvent Extraction Process by British Coal; and the Brown Coal Liquefaction Process of Japan have been developed.

Chevron Corporation developed a process invented by Joel W. Rosenthal called the Chevron Coal Liquefaction Process (CCLP). It is unique due to the close-coupling of the non-catalytic dissolver and the catalytic hydroprocessing unit. The oil produced had properties that were unique when compared to other coal oils; it was lighter and had far fewer heteroatom impurities. The process was scaled-up to the 6 ton per day level, but not proven commercially.

Pyrolysis and carbonization processes

There are a number of different carbonization processes. The carbonization conversion occurs through pyrolysis or destructive distillation, and it produces condensable coal tar, oil and water vapor, non-condensable synthetic gas, and a solid residue-char. The condensed coal tar and oil are then further processed by hydrogenation to remove sulfur and nitrogen species, after which they are processed into fuels.

The typical example of carbonization is the Karrick process. The process was invented by Lewis Cass Karrick in the 1920s. The Karrick process is a low-temperature carbonization process, where coal is heated at 680 °F (360 °C) to 1,380 °F (750 °C) in the absence of air. These temperatures optimize the production of coal tars richer in lighter hydrocarbons than normal coal tar. However, the produced liquids are mostly a by-product and the main product is semi-coke, a solid and smokeless fuel.

The COED Process, developed by FMC Corporation, uses a fluidized bed for processing, in combination with increasing temperature, through four stages of pyrolysis. Heat is transferred by hot gases produced by combustion of part of the produced char. A modification of this process, the COGAS Process, involves the addition of gasification of char. The TOSCOAL Process, an analogue to the TOSCO II oil shale retorting process and Lurgi-Ruhrgas process, which is also used for the shale oil extraction, uses hot recycled solids for the heat transfer.

Liquid yields of pyrolysis and Karrick processes are generally low for practical use for synthetic liquid fuel production. Furthermore, the resulting liquids are of low quality and require further treatment before they can be used as motor fuels. In summary, there is little possibility that this process will yield economically viable volumes of liquid fuel.

Biofuels processes

One example of a Biofuel-based synthetic fuel process is Hydrotreated Renewable Jet (HRJ) fuel. There are a number of variants of these processes under development, and the testing and certification process for HRJ aviation fuels is beginning.

There are two such process under development by UOP. One using solid biomass feedstocks, and one using bio-oil and fats. The process using solid second-generation biomass sources such as switchgrass or woody biomass uses pyrolysis to produce a bio-oil, which is then catalytically stabilized and deoxygenated to produce a jet-range fuel. The process using natural oils and fats goes through a deoxygenation process, followed by hydrocracking and isomerization to produce a renewable Synthetic Paraffinic Kerosene jet fuel.

Oil sand and oil shale processes

Synthetic crude may also be created by upgrading bitumen (a tar like substance found in oil sands), or synthesizing liquid hydrocarbons from oil shale. There are a number of processes extracting shale oil (synthetic crude oil) from oil shale by pyrolysis, hydrogenation, or thermal dissolution.

Commercialization

Worldwide commercial synthetic fuels plant capacity is over 240,000 barrels per day (38,000 m3/d), including indirect conversion Fischer–Tropsch plants in South Africa (Mossgas, Secunda CTL), Qatar {Oryx GTL}, and Malaysia (Shell Bintulu), and a Mobil process (Methanol to Gasoline) plant in New Zealand.

Sasol, a company based in South Africa operates the world's only commercial Fischer–Tropsch coal-to-liquids facility at Secunda, with a capacity of 150,000 barrels per day (24,000 m3/d).

Economics

The economics of synthetic fuel manufacture vary greatly depending the feedstock used, the precise process employed, site characteristics such as feedstock and transportation costs, and the cost of additional equipment required to control emissions. The examples described below indicate a wide range of production costs between $20/BBL for large-scale gas-to-liquids, to as much as $240/BBL for small-scale biomass-to-liquids + Carbon Capture and Sequestration.

In order to be economically viable, projects must do much better than just being competitive head-to-head with oil. They must also generate a sufficient return on investment to justify the capital investment in the project.

CTL/CBTL/BTL economics

According to a December 2007 study, a medium scale (30,000 BPD) coal-to-liquids plant (CTL) sited in the US using bituminous coal, is expected to be competitive with oil down to roughly $52–56/bbl crude-oil equivalent. Adding carbon capture and sequestration to the project was expected to add an additional $10/BBL to the required selling price, though this may be offset by revenues from enhanced oil recovery, or by tax credits, or the eventual sale of carbon credits.

A recent NETL study examined the relative economics of a number of different process configurations for the production of indirect FT fuels using biomass, coal, and CCS. This study determined a price at which the plant would not only be profitable, but also make a sufficient return to yield a 20% return on the equity investment required to build the plant.

This chapter details an analysis which derives the Required Selling Price (RSP) of the FT diesel fuels produced in order to determine the economic feasibility and relative competitiveness of the different plant options. A sensitivity analysis was performed to determine how carbon control regulations such as an emissions trading scheme for transportation fuels would affect the price of both petroleum-derived diesel and FT diesel from the different plants. The key findings of these analyses were: (1) CTL plants equipped with CCS are competitive at crude oil prices as low as $86 per barrel and have less life cycle GHG emissions than petroleum-derived diesel. These plants become more economically competitive as carbon prices increase. (2) The incremental cost of adding simple CCS is very low (7 cents per gallon) because CO2 capture is an inherent part of the FT process. This becomes the economically preferred option at carbon prices above $5/mtCO2eq.27 (3) BTL systems are hindered by limited biomass availability which affects the maximum plant size, thereby limiting potential economies of scale. This, combined with relatively high biomass costs results in FT diesel prices which are double that of other configurations: $6.45 to $6.96/gal compared to $2.56 to $2.82/gal for CTL and 15wt% CBTL systems equipped with CCS.

The conclusion reached based on these findings was that both the CTL with CCS and the 8wt% to 15wt% CBTL with CCS configurations may offer the most pragmatic solutions to the nation's energy strategy dilemma: GHG emission reductions which are significant (5% to 33% below the petroleum baseline) at diesel RSPs that are only half as much as the BTL options ($2.56 to $2.82 per gallon compared to $6.45 to $6.96 per gallon for BTL). These options are economically feasible when crude oil prices are $86 to $95 per barrel.

These economics can change in the event that plentiful low-cost biomass sources can be found, lowing the cost of biomass inputs, and improving economies of scale.

Economics for solid feedstock indirect FT process plants are further confused by carbon regulation. Generally, since permitting a CTL plant without CCS will likely be impossible, and CTL+CCS plants have a lower carbon footprint than conventional fuels, carbon regulation is expected to be balance-positive for synthetic fuel production. But it impacts the economics of different process configurations in different ways. The NETL study picked a blended CBTL process using 5-15% biomass alongside coal as the most economical in a range of carbon price and probable future regulation scenarios. Because of scale and cost constraints, pure BTL processes did not score well until high carbon prices were assumed, though again this may improve with better feedstocks and more efficient larger scale projects.

Chinese direct coal liquefaction economics

Shenhua Group recently reported that their direct coal liquefaction process is competitive with oil prices above $60 per barrel. Previous reports have indicated an anticipated cost of production of less than $30 per barrel, based on a direct coal liquefaction process, and a coal mining cost of under $10/ton. In October 2011, actual price of coal in China was as high as $135/ton.

Security considerations

A central consideration for the development of synthetic fuel is the security factor of securing domestic fuel supply from domestic biomass and coal. Nations that are rich in biomass and coal can use synthetic fuel to off-set their use of petroleum derived fuels and foreign oil.

Environmental considerations

The environmental footprint of a given synthetic fuel varies greatly depending on which process is employed, what feedstock is used, what pollution controls are employed, and what the transportation distance and method are for both feedstock procurement and end-product distribution.

In many locations, project development will not be possible due to permitting restrictions if a process design is chosen that does not meet local requirements for clean air, water, and increasingly, lifecycle carbon emissions.

Lifecycle greenhouse gas emissions

Among different indirect FT synthetic fuels production technologies, potential emissions of greenhouse gasses vary greatly. Coal to liquids ("CTL") without carbon capture and sequestration ("CCS") is expected to result in a significantly higher carbon footprint than conventional petroleum-derived fuels (+147%). On the other hand, biomass-to-liquids with CCS could deliver a 358% reduction in lifecycle greenhouse gas emissions. Both of these plants fundamentally use gasification and FT conversion synthetic fuels technology, but they deliver wildly divergent environmental footprints.

Lifecycle carbon emissions profiles of various fuels, including many synthetic fuels. Coal and biomass co-conversion to transportation fuels, Michael E. Reed, DOE NETL Office of Fossil Energy, Oct 17 2007

Generally, CTL without CCS has a higher greenhouse gas footprint. CTL with CCS has a 9-15% reduction in lifecycle greenhouse gas emissions compared to that of petroleum derived diesel.

CBTL+CCS plants that blend biomass alongside coal while sequestering carbon do progressively better the more biomass is added. Depending on the type of biomass, the assumptions about root storage, and the transportation logistics, at conservatively 40% biomass alongside coal, CBTL+CCS plants achieve a neutral lifecycle greenhouse gas footprint. At more than 40% biomass, they begin to go lifecycle negative, and effectively store carbon in the ground for every gallon of fuels that they produce.

Ultimately BTL plants employing CCS could store massive amounts of carbon while producing transportation fuels from sustainably produced biomass feedstocks, although there are a number of significant economic hurdles, and a few technical hurdles that would have to be overcome to enable the development of such facilities.

Serious consideration must also be given to the type and method of feedstock procurement for either the coal or biomass used in such facilities, as reckless development could exacerbate environmental problems caused by mountaintop removal mining, land use change, fertilizer runoff, food vs. fuels concerns, or many other potential factors. Or they could not, depending entirely on project-specific factors on a plant-by-plant basis.

A study from U.S. Department of Energy National Energy Technology Laboratory with much more in-depth information of CBTL life-cycle emissions "Affordable Low Carbon Diesel from Domestic Coal and Biomass".

Hybrid hydrogen-carbon processes have also been proposed recently as another closed-carbon cycle alternative, combining 'clean' electricity, recycled CO, H2 and captured CO2 with biomass as inputs as a way of reducing the biomass needed.

Fuels emissions

The fuels produced by the various synthetic fuels process also have a wide range of potential environmental performance, though they tend to be very uniform based on the type of synthetic fuels process used (i.e. the tailpipe emissions characteristics of Fischer–Tropsch diesel tend to be the same, though their lifecycle greenhouse gas footprint can vary substantially based on which plant produced the fuel, depending on feedstock and plant level sequestration considerations.)

In particular, Fischer–Tropsch diesel and jet fuels deliver dramatic across-the-board reductions in all major criteria pollutants such as SOx, NOx, Particulate Matter, and Hydrocarbon emissions. These fuels, because of their high level of purity and lack of contaminants, further enable the use of advanced emissions control equipment that has been shown to virtually eliminate HC, CO, and PM emissions from diesel vehicles.

In testimony before the Subcommittee on Energy and Environment of the U.S. House of Representatives the following statement was made by a senior scientist from Rentech:

F-T fuels offer numerous benefits to aviation users. The first is an immediate reduction in particulate emissions. F-T jet fuel has been shown in laboratory combusters and engines to reduce PM emissions by 96% at idle and 78% under cruise operation. Validation of the reduction in other turbine engine emissions is still under way. Concurrent to the PM reductions is an immediate reduction in CO2 emissions from F-T fuel. F-T fuels inherently reduce CO2 emissions because they have higher energy content per carbon content of the fuel, and the fuel is less dense than conventional jet fuel allowing aircraft to fly further on the same load of fuel.

The "cleanness" of these FT synthetic fuels is further demonstrated by the fact that they are sufficiently non-toxic and environmentally benign as to be considered biodegradable. This owes primarily to the near-absence of sulfur and extremely low level of aromatics present in the fuel.

Sustainability

One concern commonly raised about the development of synthetic fuels plants is sustainability. Fundamentally, transitioning from oil to coal or natural gas for transportation fuels production is a transition from one inherently depletable geologically limited resource to another.

One of the positive defining characteristics of synthetic fuels production is the ability to use multiple feedstocks (coal, gas, or biomass) to produce the same product from the same plant. In the case of hybrid BCTL plants, some facilities are already planning to use a significant biomass component alongside coal. Ultimately, given the right location with good biomass availability, and sufficiently high oil prices, synthetic fuels plants can be transitioned from coal or gas, over to a 100% biomass feedstock. This provides a path forward towards a renewable fuel source and possibly more sustainable, even if the plant originally produced fuels solely from coal, making the infrastructure forwards-compatible even if the original fossil feedstock runs out.

Some synthetic fuels processes can be converted to sustainable production practices more easily than others, depending on the process equipment selected. This is an important design consideration as these facilities are planned and implemented, as additional room must be left in the plant layout to accommodate whatever future plant change requirements in terms of materials handling and gasification might be necessary to accommodate a future change in production profile.

Neurophilosophy

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Neurophilosophy ...