Ammonia plant fertilizer

Ammonia liquor Ammonium nitrate and sulfate Anhydrous ammonia Aqua ammonia, made in ammonia plants Fertilizers, mixed made in plants producing nitrogenous fertilizer materials... 

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. 

The purified raw gas goes to a Synthol (Eischer-Tropsch) unit for catalytic conversion of CO and H2 to Hquid fuels. The tars and oils obtained from quenching the raw gas from the gasifiers go to a Phenosolvan plant to provide tar products for the refinery and ammonia for fertilizer. The Synthol plant has seven reactors, each with 1.9 x 10 m /h (1.6 x 10 ft /d) gas feed. Annual plant production is 1.5 x 10 t motor fuels, 185 x 10 t ethylene,... 

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. 

In ammonium phosphate and mixed and blend fertilizer (G) production, another possibility is to design for a lower-pressure steam level (i.e., 42-62 atm) in the ammonia plant to make process condensate recovery easier and less costly. 

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. 

Shown in Figure 10, this ammonia plant is a major part of the overall fertilizer site complex. Other major facilities include urea plant, steam system, and cooling water system. Most of the ammonia is used to make granulated urea product. The other raw material for urea synthesis is C02 from the C02 capture system in the ammonia plant, supplemented with a small stream from an adjacent business. The ammonia production and the C02 available from the ammonia plant are never precisely in balance, in part because of the overall stoichiometric yields of ammonia and C02 from the natural gas feedstock. C02 is the limiting feedstock for the urea plant and its production rate in the ammonia plant sets the urea plant production rate since there is no intermediate C02 storage to buffer the urea production from the C02 production rate. Ammonia that is produced in excess of that which is used to make urea... 

Since no economical nitrogen fixation process that starts with nitrogen oxides has been discovered, ammonia has developed into the most important building block for synthetic nitrogen products worldwide. Prior to World War II, ammonia production capacity remained relatively stable. But during the war the need for explosives caused an increase in the production of ammonia for nitric acid manufacture. Then, after the war, the ammonia plants were used to manufacture fertilizers. As a result, there was a rapid increase in fertilizer consumption. The advantages of fertilizers were emphasized, and production capacity increased by leaps and bounds. 

Figure 3.13. Forecast ammonia plant capacity increases 1997 to 2003. (Reproduced by permission of International Fertilizer Industry Association)...

Qafco (in Qatar) is working with Uhde to build an ammonia plant with a capacity of 3,500 tonnes per day. Startup is scheduled for 2004216. The Saudi Arabian Fertilizer Co. (SAFCO) let a contract in 2002 for an ammonia plant with a capacity of3,000 tonnes per day. Startup is scheduled for 20Q5215. 

Ohri, I.J., Energy Conservation Measures in Ammonia Plants at IFFCO Kalol and Phulpur Units, IFFCO, India, www.fertilizer.org/ifa/publicat/pdf/tech0039.pdf, 2001. 

Ammonia in Multinutrient Fertilizers. All the ammonia-based fertilizers discussed thus far contain only one of the three major plant nutrients, namely nitrogen. Referring again to Fig. 24.8, one may see that ammonia is the source of fertilizer nitrogen also, either directly or via nitrogen solids or solutions, in multinutrient fertilizers. These are fertilizers that contain two or three of the major plant nutrients—nitrogen, phosphorus, and potassium. Ammonium phosphates, both mono- and di-,... 

D. Claes, N. Frisse, R. Hakman Methanol co-production as a revamp otopn for an ammonia plant FAI Symposium Advances in Fertilizer Production , New Delhi (April 1995). 

Urea is used as a fertilizer and is made by reacting ammonia with carbon dioxide. The reactions essentially proceed to equilibrium, but the process must be designed to minimize emissions of ammonia. The urea is usually formed into a solid product by prilling. U.S. 6,921,838 (to DSM B.V.) describes a novel process for urea production. Estimate the cost of producing ammonia via this route. Assume that carbon dioxide is available as a byproduct of the ammonia plant (see problem E.7.1). 

Since over half of the hydrogen is utilized in the production of ammonia (fertilizer production) and is carried out in the modern ammonia plants (hydrogen production and utilization in integrated plants), all three processes will be dealt with in detail in Section 1.4.1.2. 

Further industrial examples are the chemical plants producing phosphatic fertilizers or phosphoric acid, which may also have quite acidic discharges, and ammonia plants or coal-coking plants can generate quite alkaline streams. 

Since about 1950, most urea producing units have been based on ammonia-carbon dioxide feedstocks passed through high-pressure equipment, hence the close association with ammonia plants [63]. Over the last 20 years in North America urea production volumes have grown faster than ammonium nitrate for the supply of fertilizer nitrogen (Table 11.10). 

The majority of the process development occurred in western Europe and the United States. Since 1975, many plants have come on-line in other parts of the world based on this technology. A shift can be seen in the worldwide ammonia distribution as shown in Table 3.1 [2], The shift has been to less industrial countries with large populations that require the ammonia for fertilizer production. 

Ammonia is the principal component in the fertilizer production. The world ammonia capacity for 1995-1996 is estimated at 123,640,000 tons of nitrogen per year [70], Ammonia plants are high energy consumers, and selection of the feedstocks is the most important factor in determining the capital investment and production costs. The availability and cost of raw materials are factors to be taken into account when deciding on the construction of a new ammonia plant. The primary feedstocks for ammonia production include natural gas, naphtha, heavy residual oil, coke gas, and coal. Of all these feedstocks, natural gas is the raw material of choice when available because it ensures minimum investment and production costs, a plant that is easy to operate, and minimal environmental problems. Therefore, steam reforming of natural gas has become the most widespread process for ammonia production. 

The Atmospheric Nitrogen Corporation, now operating the largest direct synthetic ammonia plant in the United States, is preparing for the erection of a large plant for this process for the production of fertilizer materials at Hope-well, Virginia. Indeed it is reported that construction has already started on the Hopewell site and that much of the equipment has been ordered and the fabrication of some completed. This plant will mark the entrance of the direct synthetic ammonia process for fertilizer production in this country and it is expected that expansion will be rapid. 

The quantity of food required to feed the ever-increasing human population far exceeds that provided by nitrogen-fixing plants. (Section 14.7) Therefore, human agriculture requires substantial amounts of ammonia-based fertilizers for croplands. Of all the chemical reactions that humans have learned to control for their own purposes, the synthesis of ammonia from hydrogen and atmospheric nitrogen is one of the most important... 

Note that in several cases, the plants produce combined products. Both ethylene and propylene are produced from a naphtha cut obtained from the fractionation of crude oil. A combined ammonia-urea fertilizer plant is common. The electrolysis of a brine solution produces both chlorine and sodium hydroxide. Recent literature data are usually given for plant capacities in tonnes per year (1 tonne = 1,000 kg) or tons per day (1 ton = 2,000 lb) of product, but the capacity data in Table 16.8 are given in pounds of product per year. Also included in the table is the value of Q for use in the following modification of Eq. (16.3) ... 

The first ammonia plants were quite small, 25-50 tpd, and costs remained high. Much of the ammonia was used to produce explosives or industrial chemicals. Fertilizer use remained small because chemical nitrogen was too expensive for liberal use on farm crops other than those of high cash value. Even as late as 1950 many agriculturists advocated that principal reliance for nitrogen supplies be placed on legumes grown in rotation with other crops. 

---