Ammonia From Coal

About 10% of the world s ammonia production is based on coal, coke, or lignite. About half of the coal-based capacity is in the People s Republic of China where there are over 1,000 small plants with capacities ranging from 3,000 to 10,000 tpy [39]. It was reported that 1,100 small coal-based ammonia plants were built between 1966 and 1974 and 100 more per year were being added in 1975 [40]. The technology of one of these plants has been described [41]. The feedstock was lump anthracite or semi-anthracite although it was r ported that briquetted coal or lower grade coal was used 

Staege lists 13 plants built since 1950 for direct use of coal in India, Greece, Turkey, South Africa, Pakistan, Thailand, India, and Zambia I42[. Most of them are small (40 to 340 tpd capacity), and some of them have been converted to other feedstock. However, the list included three large plants (900-1,000 tpd) of wiiich two are in India, specifically Talcher and Ramagundam. The third one is in South Africa its operation has been described by Waitzman [43]. TVA built and operated a 

Q al gasification processes for ammonia production can be classified according to the method of gasification as fixed-bed G-urgi), fluidized bed (Winkler), or entrained bed (Koppers-Totzek and Texaco). Tne so-called fixed bed ga cation is more accurately called a moving bed. Lump coal (5-30 mm) is charged at the top arxi descends countercurrently to the gas stream. As it descends, it is first dried and preheated, then carbonized, and fi- 

The Lur] movmg bed gasifier usually is operated at 3 ME figure 6.20). It requires the least amount of oxygen - 

R-1 Lurgi gasifier S-E Gas cooler 4 scrubber E-3 Utility boiler E-4j E-6 Conversion coolers 

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Ammonia from coal gasification has been used for fertilizer production at Sasol since the beginning of operations in 1955. In 1964 a dedicated coal-based ammonia synthesis plant was brought on stream. This plant has now been deactivated, and is being replaced with a new faciUty with three times the production capacity. Nitric acid is produced by oxidation and is converted with additional ammonia into ammonium nitrate fertilizers. The products are marketed either as a Hquid or in a soHd form known as Limestone Ammonium Nitrate. Also, two types of explosives are produced from ammonium nitrate. The first is a mixture of fuel oil and porous ammonium nitrate granules. The second type is produced by emulsifying small droplets of ammonium nitrate solution in oil. 

Coal is expected to be the best domestic feedstock alternative to natural gas. Although coal-based ammonia plants have been built elsewhere, there is no such plant in the United States. Pilot-scale projects have demonstrated effective ammonia-from-coal technology (102). The cost of ammonia production can be anticipated to increase, lea ding to increases in the cost of producing nitrogen fertilizers. 

D. Waitzman, Technical and Economic Aspects of Producing Ammonia from Coal, International Fertilizer Development Center, Muscle Shoals, Ala., 1986. 

Burkheiser Also known as the sulfite-bisulfite process. A complicated process for removing hydrogen sulfide and ammonia from coal gas by absorption in an aqueous solution containing ammonia, iron oxide, and elemental sulfur. The end products are sulfur and ammonia. Invented by K. Burkheiser in 1907 and developed in Germany in the early 1900s. 

A fourth type of innovation is one which results in an entirely new process in the engineering sense. All the process coefficients may be very different in fact, entirely different inputs may be used, or new physical or chemical principles may be employed. In contrast to production of ammonia from coal, steam reforming of natural gas was such an innovation, as was the shift from propellor to jet aircraft. Current research to produce nitrogen-fixing (ammonia-producing) bacteria that are symbiotic with corn through DNA manipulation is innovative activity of the fourth type. 

F.H. Franke, E. Pattas, E. Nitschke, J. Keller TVA Ammonia from coal symposium 1979, 86/96... 

I. Dybkjaer, in Ammonia from Coal Symposium, TVA Muscle Schoals Alabama, USA p. 133. 

Table VIII presents the estimated revenue requirements. The methanol case uses regulated utility financing, and the ammonia case, non-regulated industrial financing, based on considerations of the likely markets to be served by these products. The estimated costs of producing methanol or ammonia from wood are higher than the costs of producing methanol or ammonia from coal. This is ejqplained in part by production rates (the rates from wood-derived methanol plants are about one-tenth of those from "typical" coal-derived methanol plants ammonia production rates are similar from the two resources since the ammonia market is typically demand-constrained) and partially by feedstock differences (e.g., green wood is half moisture).

TVA ammonia-from-coal project, Chem. Eng. News 57(33), 27, June 4 (1979). 

Waitzman, D, A. 1985. TVA Ammonia from Coal Projects, Ammonia Production via Coal Gasification, Muscle Shoals, AL, U.S.A. 

K. Chaurey and K. Sharma. "Coal Based Ammonia Plant-Preliminary Operating Experience of Coal Gasification at Talcher and Ramagundam Fertilizer Plants of the Fertilizer Corporation of India." In Proceedings of Ammonia From Coal Symposium, Muscle Shoals, Alabama, July 1979. 

E. E. Bailey and T. K. Subramaniam. "Winkler Coal Gasification Process and Its Application in Ammonia Synthesis Plants." In Proceedings of Ammonia from Coal Sjraposium, Muscle Shoals, Alabama, May 1979. 

T. W. Nurse, Ammonia From Coal Choosing a Design. Proc.—Int. Symp. Large Chem. Plants Energy, Feedstocks, Processes, 5th, p. 131 (1982). 

It is generally necessary to remove ammonia, hydrogen cyanide, and pyridine bases from coal gases prior to industrial or domestic use to meet purity requirements of downstream systems. In additimi, ammonia and the pyridine bases are relatively valuable chemicals and their recovery as by-fvoducts can be ecoitomically attractive when significant quantities are produced. Before the advent of syntbetic ammonia processes, by-product ammonia from coal... 

Vasan, S.. 1979, The Holmes-Stretford Process for Desulfurization of Tail-Gases from Acid-Gas Systems, Paper presented at the Ammonia-from-Coal-Symposium, Muscle Shoals, AL, May 8. 

Case 4. TV A Ammonia from Coal Plant, Projected. 

Case 5. TVA Ammonia from Coal Plata, Op. data. 

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