Fertilizers manufacture

As is evident from the listing in Table 3, the fertilizer manufacturer has a wide array of compounds from which to choose. Final choices of products and processes therefore rest heavily on such other factors as availabiUty and cost of raw materials, economy of processing, safety of product, economy of handling and shipping, acceptabiUty of physical form and physical behavior of the product, and farmer acceptance. 

Calcium. Soil minerals are a main source of calcium for plants, thus nutrient deficiency of this element in plants is rare. Calcium, in the form of pulverized limestone [1317-65-3] or dolomite [17069-72-6] frequendy is appHed to acidic soils to counteract the acidity and thus improve crop growth. Such liming incidentally ensures an adequate supply of available calcium for plant nutrition. Although pH correction is important for agriculture, and liming agents often are sold by fertilizer distributors, this function is not one of fertilizer manufacture. 

Modem commercial wet-acid purification processes (see Fig. 4) are based on solvents such as C to Cg alcohols, ethers, ketones, amines, and phosphate esters (10—12). Organic-phase extraction of phosphoric acid is accompHshed in one or more extraction columns or, less frequently, in a series of countercurrent mixer—settlers. Generally, 60—75% of the feed acid P2 s content is extracted into the organic phase as H PO. The residual phosphoric acid phase (raffinate), containing 25—40% of the original P2O5 value, is typically used for fertilizer manufacture such as triple superphosphate. For this reason, wet-acid purification units are almost always located within or next to fertilizer complexes. 

Condensed Phosphoric Acid. The largest use of polyphosphoric (superphosphoric) acid is as an intermediate in the production of high quahty Hquid fertilizers. The TVA pioneered the development of electric-furnace superphosphoric acid for this appHcation. However, wet-process superphosphoric acid prepared by evaporation of water from wet-process phosphoric acid has almost completely replaced furnace-grade acid in fertilizer manufacture. 

Part 418 fertilizer manufacturing point source category... 

Fertilizer manufacturers generally benefited from the stabilized sulfur price and are somewhat insulated from the effect of imports because of the high value of steam (and electricity) produced by thek sulfuric acid plants. 

European Fertilizer Manufacturers Association. 1995a. "Production of NPK Fertilizers by the Nitrophosphate Route." Booklet 7 of 8. Brussels, and 1995b. "Production of NPK Fertilizers by the Mixed Acid Route." Booklet 8 of 8. Brussels. 

Describe typical sources and types of air emissions resulting from fertilizer manufacturing. What are some pollution prevention practices used in this industry What are some of the emission control devices used and for what purposes ... 

The facility stores ammonia to supply nearby fertilizer manufacturers. It is transported to the plant by ship, transferred and stored in the tank for transfer as needed. The facility mainly consists of a storage tank, a refrigeration system, a control system, and a pipe connecting the tank with the plants. Ammonia is transported and stored as a refrigerated liquid (-33 C) at atmospheric pressure. 

European Council for Plasticisers and hitermediates (ECPI), 257 European Council of Vmyl Manufacturers (ECVM), 257 European Crop Protection Association (ECPA), 257 European Environmental Agency (EEA), 282 European Environmental Research Organization, 276 European Fertilizer Manufacturers Association (EFMA), 257... 

In the fertilizer manufacturing scheme, the wet process phosphoric acid most commonly ensues from dissolution of sedimentary phosphate rock in sulfuric acid. Such acid solution contains around 1 g 1 1 uranium which is recovered as the byproduct. This task is accomplished by three well-proven extraction processes, some salient details of which are presented in Table 5.10. 

Transporting the dust to an offsite processor for thermal treatment and removal of zinc, chemical fixation, glassification, or fertilizer manufacture... 

USEPA s Risk Management Program monitors large chemical producers, including petroleum refiners, petrochemical manufacturers, and nitrate-fertilizer manufactur-... 

As described in Chapter 4, pesticide and fertilizer manufacturing is largely an outgrowth of mihtary technology developed during World War II. Discoveries in this field showed that pesticide production could be cost-effective, and... 

The basic raw materials used by the phosphorus chemicals, phosphates, and phosphate fertilizer manufacturing industry are mined phosphate rock and phosphoric acid produced by the wet process. 

As previously mentioned, fertilizer manufacturing may create problems within all environmental media, that is, air pollution, water pollution, and solid wastes disposal difficulties. In particular, the liquid waste effluents generated from phosphate and mixed and blend fertilizer production streams originate from a variety of sources and may be summarized [17,27] as follows (a) ammonia-bearing wastes from ammonia production (b) ammonium salts such as... 

The sources and characteristics of wastewater streams from the various subcategories in phosphate and phosphate fertilizer manufacturing, as well as some of the possibilities for... 

Cooling water constitutes a major portion of the total in-plant wastes in fertilizer manufacturing and it includes water coming into direct contact with the gases processed (largest percentage) and water that has no such contact. The latter stream can be readily used in a closed-cycle system, but sometimes the direct contact cooling water is also recycled (after treatment to... 

In ammonium phosphate production and mixed and blend fertilizer manufacturing, one possibility is the integration of an ammonia process condensate steam stripping column into the condensate-boiler feedwater systems of an ammonia plant, with or without further stripper bottoms treatment depending on the boiler quality makeup needed. 

Air streams from the digestion system, vacuum cooler, concentrator, and other areas where fluorine is evolved are connected to a highly efficient absorption system, providing extremely high volumes of water relative to the stream. The effluent from this absorption system forms part of the recycled water and is eventually discharged as part of the product used for fertilizer manufacture. The Minnesota plant requires a constant recirculating water load in excess of 3000 gpm (11.4 m /min), but multiple use and recycle reduce makeup requirements to less than 400 gpm (1.5 m /min) or a mere 13% of total water use. 

According to the literature [3,17,33], the heterogeneous nature of fertilizer production plants precludes the possibility of presenting a typical case study of such a facility. Nevertheless, the wastewater flows, the characteristics, and the treatment systems for a phosphoric acid and N-P-K fertilizer plant were parts of a large fertilizer manufacturing facility. The full facility additionally included an ammonia plant, a urea plant, a sulfuric acid plant, and a nitric acid plant. The typical effluent flows were 183 m /hour (806 gpm) from the phosphoric plant and 4.4 m /hour (20 gpm) from the water treatment plant associated with it, whereas in the N-P-K plant they were 420 m /hour (1850 gpm) from the barometric condenser and 108 m /hour (476 gpm) from other effluent sources. 

Kiff, R.I. Water pollution control in the fertilizer manufacturing industry. In Manufacturing and Chemical Industries Barnes, D. et al., Eds. Longman Scientific Technical Essex, UK, 1987. Koziorowski, B. Kucharski, J. Industrial Waste Disposal Pergamon Press Oxford, UK, 1972 142-151. 

Lund, H.F. (Ed.) Industrial Pollution Control Handbook McGraw-Hill New York, 1971 14-6-14-8. Markham, J.H. Effluent Control on a Fertilizer Manufacturing Site Fertilizer Soc. of London, London, 1983 Proc. 213. 

Uses. Cleaning compounds fertilizers manufacture of glazes and enamels... 

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