South African institutional investors, pension funds, and large companies took the lead. Small investors were attracted by promises of preferential allocation treatment, and foreign investors were particularly interested because they were allowed to make their purchases using the financial rand, while dividends would be paid at the ordinary commercial exchange rate.
At the time, the financial rand was at a discount in excess of 30 percent as against a more normal rate of about 12 percent. The public issue was more than 30 times oversubscribed. Foreign investors did not do as well as they hoped out of the allocation. In , on the basis of the expanded capacity provided by Sasol 2 and 3, Sasol Limited was able to begin moving beyond the provision of feedstock for the country's chemical industry into the production of fertilizers and various specialty chemicals.
Existing producers did not welcome this competition. Still a relative newcomer to the industry, Sasol was nonetheless part of the general effort to increase South African specialty chemical output. In addition to saving substantial amounts of foreign exchange by reducing reliance on imports, Sasol also planned to produce for export.
In , major investment plans were approved for the company to expand production of a range of products that would contribute to this end. In relations with its workers, Sasol was facing, like most other South African enterprises, increasing pressure from African trade unions for improvements in pay, working conditions, and housing.
A nine-day strike in , for example, was resolved by the payment of a food allowance for African workers not living in hostel accommodation. More serious industrial action in resulted in Sasol's being criticized by the Industrial Court for using "rough and ugly tactics" in dealing with a strike by members of the Chemical Workers' Industrial Union. The company was, the court held, more interested in forcing capitulation than in negotiating a financial settlement. A subsequent appeal, however, found the company's actions justified.
Apart from specific trade union issues, Sasol was also a major target for political activists seeking to put pressure on the South African government to bring the apartheid system to an end.
In June , for example, there was a well-coordinated attack on Sasolburg, showing evidence of detailed knowledge of the plant and its weak security points. Bombs placed in the offices at Fluor, then constructing Sasol 2 and 3, were defused only a short time before they were set to explode. During this period Sasol placed considerable emphasis on research and development, which had been the platform for considerable technological advance.
On this basis it not only built up its manufacturing base within South Africa, but also provided technical services abroad. Most notable was technical support for some U. By the beginning of the s the company was calling for the expansion of synthetic fuel production in South Africa.
It turned to government and other industries to provide the large amount of capital required, but it was not forthcoming. As the apartheid system was being dismantled in the early s, Sasol was searching for ways to remain competitive in the emerging free market economy. Deregulation and the end of government protection made it clear that the company would no longer be able to survive on the profits from its synthetic fuel business.
In synthetic fuel still accounted for 41 percent of the company's profits, much of which were in the form of government subsidies. The government's plan to gradually phase out these subsidies--which amounted to R 1. The most obvious solution involved the expansion of the company's petrochemical business. With significantly lower operating costs, Sasol had a distinct edge over its European competitors. The key, however, was gaining a foothold in previously unexplored global markets.
To this end, the company entered into a number of strategic partnerships with overseas corporations in the mids. These agreements included deals with Merichem for the production of phenolics and with DHB for the manufacturing of explosives.
In Sasol joined forces with the German chemicals firm Schumann, giving the joint company control over one-fifth of the international wax market, and its acquisition of AECI made it the third largest producer of explosives in the world. In spite of this shift toward petrochemicals, however, Sasol remained committed to developing an economically viable synthetic fuel throughout the s. Much of the company's efforts remained focused on the possibilities of coal.
By Sasol had succeeded in lowering the operating costs of its synthetic fuel reactors significantly, and it became conceivable that its product might become competitive with standard crude oil. At the same time, Sasol began exploring the possibilities of alternative forms of fuel conversion, most notably natural gas. By the joint venture emerged into a new company, Sasol Chevron Holdings, dedicated to establishing similar natural gas-to-oil refineries around the world.
Clearly, Sasol was finding its way quite well as it took its first steps into the global economy. Investors were not blind to the company's potential; Sasol's stock price rose 50 percent between and , prompting the Dow Jones World Sustainability Index to name it the second best performer of the year.
While Sasol was still feeling its way in the post-apartheid economy at the beginning of the new millennium, it had every reason to feel confident that its past success in South Africa was going to translate into future success worldwide. Toggle navigation. The first process produces mainly higher boiling point materials consisting of waxes, some oils with medium boiling point such as dlesel oils, and smaller amounts of gasoline, liquefied petroleum gas and chemicals.
In contrast, the second process produces mainly low boiling point materials such as liquefied petroleum gas and gasoline as well as a considerable amount of chemicals such as alcohol and acetone.
The unique combination of the two processes yields virtually the full range of products normally derived from crude oil In addition to a number of others usually manu- factured 1n petrochemical plants.
Sasol I 1s also the major supplier of Industrial gas via a high-pressure pipeline to South Africa's Industrial areas. Sasol I has become the hub of South Africa's chemical Industry, a group of about 30 plants producing a large range of petrochemical products: fertilizers, plastics, synthetic rubber, detergents, chemicals. In order to meet the ever growing demand for Its products, Sasol I has successfully Initiated and completed Improvement and expansion programs over the years to supply Important feedstocks butadiene, styrene, ammonia, ethylene to the chemical Industry.
As a result of rising crude oil prices since the Yom Klppur War and the Arab oil boycott, the South African government 1n a major move away from dependence on Imported crude oil announced 1n December that 1t would build a second oil-from-coal complex, Sasol II. In addition, the move will save considerable sums 1n foreign exchange which South Africa uses to pay for Imported oil. Sasol II will be three times the design capacity of Sasol I, or In terms of petroleum production, Sasol II will be the equivalent of a refinery capable of refining 2.
The plant will consume 14 million tons Sasol I uses both the fixed bed and circulating fluid bed synthesis processes to produce the full range of light to heavy hydrocarbons. However, the objective of Sasol II 1s to produce motor fuels gasoline and dlesel for which the circulating fluid bed Is more suited.
In addition, the possibilities for scale up are limited for the fixed bed reactor. For these reasons, the Sasol II plant will use only circulating fluid bed synthesis reactors which were perfected at Sasol I. Construction got under way In on a flat, treeless acre hectare site about 80 miles km east of Johannesburg. The work force reached 15, during peak construction and the plant 1s scheduled for completion early In In addition, a town called Secunda Latin for second Is being built nearby.
The new Iranian revolutionary government had decided to cut off oil supplies to South Africa. Iran had been South Africa's principal supplier. Sasol III will be almost an exact copy of Sasol II to save design costs, and may be ready for full production by Once the three plants are 1n operation, they will produce about , barrels of oil per day, approximately half of South Africa's needs 1n the 's.
The units that make up a Sasol plant along with the reasons for their selection are described 1n this section. Differences between the three Sasol plants will be pointed out. A block diagram of the Sasol I process 1s shown 1n Figure 2. Production amounts to five million tons 4. A typical analysis Is shown 1n Table 1. The coal 1s present 1n three seams, having mineable heights of 8 to 10 feet 2.
The seams are separated by layers of shale, mudstone, and sandstone of varying thickness. The mine 1s under to feet 30 to 60 m of white sandstone. The mining technique used 1s the mechanized room-and-pWar. Mined coal 1s transported via conveyor to primary crushers situated at the bottom of the Inclined coal hauling shafts. The coal 1s lifted to the surface by conveyor and discharged Into storage bunkers of 12, ton 11, mt total capacity.
The final product consists of two coal sizes, less than 0. Coal Is kept damp on the con- veyor belts by water sprays at suitable points to prevent dust formation.
The less than 0. The Lurgl pressure gaslfiers are fixed-bed, water-cooled reactors that gasify the coal In the presence of oxygen and steam to yield a syn- thesis gas containing methane, carbon monoxide, hydrogen, carbon dioxide, ammonia, hydrogen sulflde, steam, and numerous other compounds.
Lurgl pressure gaslfiers were selected because they had already been demonstrated 1n smaller sized Installations and had the advantage of being able to work on the rather low grade, high ash coal available to Sasol I. The fact that they operated at a pressure of approximately ps1 kPa which was also the desired operating pressure for the Flscher-Tropsch plant was an additional advantage. Thirteen Lurgl gaslfiers consume coal at a total rate of approximately 8, tons mt per day.
These gaslfiers are 12 feet 3. On an annual basis, At this level, gas production 1s actually limited not by gasification but rather by gas purification capacities. The Lurgl gaslfiers operate on the principle of countercurrent flow of coal to steam and oxygen which offers the best conditions for heat and mass transfer and optimum efficiency.
The overall thermal efficiency of the gaslfler system 1s approximately Oxygen Is produced In one of the world's largest air separation plants. The oxygen Is used 1n the Lurgl gaslffers as well as 1n the partial oxidation methane reforming plant. The nitrogen Is used 1n an ammonia plant.
Conventional pulverized fuel boilers are used. The steam generated Is used not only for the gasification of coal, but also 1n the various plants Inside and outside the Sasol complex.
The residual carbon 1s completely burned out of the ash with oxygen 1n the combustion zone at the bottom of the Lurgl gaslflers. This exothermic reaction helps supply the heat for the endothermic gasification reaction In the upper part of the gaslflers.
The residue 1s essentially burned-out ash which Is transported from the gasification and power plant areas by water In a low velocity sluiceway to the ash dewaterlng unit.
Coarse ash 1s removed by conveyor belts to an ash dump. The fine ash 1s concen- trated 1n a thickener and the concentrated fine ash 1s then dewatered 1n a slimes dam.
The ash contains soluble Inorganic salts that will leach out. The ash system 1s however an evaporative system for water and re- quires water make-up and no purge. Hater drainage from the slimes dam 1s collected and pumped back Into the ash sluiceway system. To prevent water seepage, the slimes dam was given an Impervious clay layer from clay available on site. The slimes dam was built with an extensive drain- age system to recover all seepage for return to the ash sluiceway system.
Coarse ash contains no excess water and at least the outside of the dump soon dries out to such an extent that It will absorb rain water. No evidence of seepage from the ash dump has been found and no measures are taken against seepage. Success has been achieved In growing grass on the dumps to make them aesthetically acceptable. Regular samples of water from boreholes 1n the vicinity of Sasolburg have been taken over the years and no evidence of underground water pollution has been found.
In addition, the gas contains cyanide compounds, tars, oils, phenols, organic sulfur com- pounds, and numerous other Impurities 1n minor quantities. The Iron- containing Flscher-Tropsch catalyst Is very sensitive to sulfur, cyanide, and other compounds.
Efficient purification of the synthesis gas Is an essential requirement for high Flscher-Tropsch conversion rates. After separation of entrained coal dust, the raw synthesis gas 1s cooled 1n a sequence of waste heat boilers and condensers. The raw gas contains large quantities of undecomposed gasification steam.
During gas cooling this steam Is condensed and the resulting aqueous 11quor contains the water-soluble components that were 1n the gas, chiefly phenols and ammonia. The tars and oils are also separated from the synthesis gas during cooling. The oil and aqueous liquor streams are fed to tar distilla- tion and Phenosolvan plants respectively. In the tar distillation plant, road primer, creosotes, and lighter naphthas fractions are separated.
The naphthas are hydrogenated and distilled to produce benzoles for solvent use and for blending Into gasoline. In the Phenosolvan plant, the aqueous liquor Is treated by solvent extraction with an oxygen-containing organic solvent, butyl acetate, to remove the phenol compounds. The ammonia Is then recovered by stripping with steam and converted to ammonium sulfate for fertilizer manufacture. There are 5. Treated liquor 1s used 1n the factory for removal and transport of ash from the gaslflers.
Ash acts as an adsorbent, reducing the residual oil content of treated liquor to less than 2. These Impurities are removed by methanol In the Rectlsol plant. The Rectlsol process 1s based on the capability of one solvent, cold methanol, to absorb all Impurities present In gases from coal gasification tn a single process step.
A typical composition of raw and pure synthesis gas Is shown In Table 2. The extremely pure gas from the Rectlsol process 1s suitable for the sensitive Flscher-Tropsch synthesis catalyst. The main energy consumption In the Rectlsol unit 1s that used to drive the methanol circulation pumps and the refrigeration compressors.
Approximately 0. The off-gas containing carbon dioxide and hydrogen sulflde from the Rectlsol plant 1s used as an expansion gas. Before this gas 1s vented to the atmosphere, hydrogen sulflde 1s removed and recovered as elemental sulfur 1n a Stretford sulfur recovery unit.
The Stretford unit was Installed In Some hydro- carbons and other Impurities are still present 1n the vent gas. The purified gas from the Rectlsol plant 1s divided Into two streams.
The larger stream Is fed directly to the fixed bed Arge synthesis units where a stationary pellet1zed catalyst Is used. The gas conversion Is not complete. The tall gas from the Arge units contains 1ow-bo1l1ng hydro- carbons and carbon dioxide. These are removed In a Rectlsol wash unit at subzero temperatures. The washed gas together with the remainder of the fresh gas from the purification plant enters a reforming plant where methane Is reacted with steam and oxygen over a nickel catalyst to produce additional carbon monoxide and hydrogen.
After adjustment of the hydrogen- carbon monoxide ratio, the gas 1s fed to the fluid bed Synthol plant where a circulating powdered catalyst 1s used. The tall gas of this plant Is also recycled to the reforming units after removal of carbon dioxide.
For both the Arge and Synthol plants there are recovery and refining plants downstream. The fixed bed reactor produces In general straight-chain hydrocarbons with a high average molecular weight In the range of dlesel oil and parafln waxes and a relatively low percentage of gasoline, liquefied petroleum gas, and oxygenated compounds alcohols, ketones, organic adds , The fluid bed process produces branched oleflns of a lower average molecu- lar weight 1n the range of liquefied petroleum gas and gasoline, little h1gh-bong material, and some oxygenated products Table 3.
Although the basic chemistry for both reactors Is the same, the different tempera- tures, method of catalyst contacting, recycle ratios, feed gas composi- tions, and hydrogen partial pressures employed 1n the two systems result not only 1n a difference In product selectivity, but also 1n a difference 1n the properties of hydrocarbons within the same boiling range.
In general, the higher the reaction temperature the higher the content of oleflns and the lower the average molecular weight of the products. Inside each shell there are 2, vertical tubes, 2 Inches 5 cm In diameter, containing the pelletlzed Iron catalyst. The tubes are surrounded on the shell side by a steam jacket.
The gas Is passed over the catalyst from top to bottom and the heat released by the exothermic reaction 1s absorbed by boiling the water In the shell. In March the Indian government announced that it had awarded the north Arkhapal coal block in Orissa to Strategic Energy Technology Systems Ltd, a joint venture between the Tata Group and Sasol Synfuels International, the international synfuels subsidiary of Sasol.
In early Orissa's Chief minister Naveen Patnaik told reporters that "though we have not identified the location, the proposed plant will be somewhere in the state. The Business Standard also stated that the project "requires 3, acre of land for its main plant, additional land would be required for setting up coal mines, benefication plants, coal handling plants, water reservoirs, power plants and a township" and would involved the establishment of a megawatt power station.
The newspaper also reported that the joint venture was "yet to make a formal application" for the plant the company was pressing the state government "to provide adequate facilities for early commissioning of the project. Sasol is also considering a coal-to-liquids plant in China with Shenhua Group and in signed a memorandum of understanding with Indonesia to investigate an an 80, barrel-a-day coal-to-fuel plant.
On March 7, , it was announced that the companies received approval from the Chinese environmental ministry for the plant.
Sasol uses proprietary technology to produce diesel, gasoline and jet fuel from coal and gas. Sasol has gas-to-liquids plants in South Africa and Qatar. Sasol said it is designing the Louisiana plant to produce 96, barrels of fuel. The facility will include a gas processing plant, a chemical plant, and a refinery, and will be located near shale gas fields in Texas.
Burning is scheduled to begin in It has one CDM approved project for destruction of nitrous oxide, qualifying it for Certified Emission Reductions in that it could sell off. Sasol also attempted to register the substitution of gas for coal in its energy feeds as a CDM project. Sasol has also spoken out to oppose legally-binding reductions in greenhouse gas emissions. Yet Eskom does not appear in the JSE report because it is not a listed company.
In September , Sasol set off the world's first passenger flight powered with only synthetic jet fuel synfuel , produced from coal. The fuel, produced by the coal-to-liquids CTL process, is the only fully synthetic jet fuel to have been approved as a commercial aviation turbine fuel. Sasol CEO Pat Davies said that the new jet fuel had undergone significant testing, burning liters of fuel in the process.
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