Hydro Fertilizers

In the Minifos process of Fisons (now Hydro Fertilizers), ammonia and phosphoric acid (45 - 54 % P2O5) react at 0.21 MPa to give an N/P ratio of 1 (see Figure 12.2). The liquid product is flash-sprayed in a natural-draught tower, where the droplets solidify to form a powder with 6% to 8% residual moisture296. 

Figure 12. Hydro Fertilizer s granular DAP process. (Reproduced by permission of Wiley-VCH)...

Methods for making higher strength P205 acid have been known for a long time. The basic hemihydrate-dihydrate process shown in the Hydro Fertilizer flowsheet, Fig. 23.12, is similar to the initial process attempted in 1931 at the Cominco plant at Trail, BC. The hemihydrate-dihydrate process failed there, mostly because of inadequate filters, but the Dorr dihydrate process did emerge successfully. 

Table 11.21. Raw Material and Product Analyses for Norsk Hydro Fertilizers Phosphoric Acid Processes (wt %)... 

Another approach to limit energy consumption is the use of pressure reactors as promoted by Norsk Hydro Fertilizers 126]. They claim the following advantages ... 

Figure 12.12. Norsk Hydro Fertilizers Draft Tube Reactor.

Two weeks after planting in the pipes, the plants were thinned to 35 pipe per pipe each and the cups to one plant each, and the treatments begun. Each first, third and fifth day of the week for twelve weeks the pipes were flushed with three liters of tap water poured in the elbow end. The water flowed past the plant root systems and drained out the screened end of the pipes into a flask. One hundred milliliter aliquots of this water ( root exudate ) were used to water the soybean plants in the cups three times weekly. After each flushing, two liters of a low nitrogen (50 ppm N) complete nutrient solution (Peter s Hydro-sol ) were added to each pipe. The soybean plants in cups were watered as needed at other times with tap water. On alternate weeks the soybean plants were fertilized with the complete nutrient solution. At 4, 8 and 12 weeks after the root exudate treatments started eighty soybean plants (10 treatments x 2 soybean varieties x 4 blocks) were randomly chosen for analysis. The soil was washed free of the plant roots and each soybean plant was divided into roots, nodules, stems, leaves and fruits. The plant parts were dried at 105°C for four days and weighed. 

Hydrogen production has commercial roots that go back more than a hundred years. Hydrogen is produced to synthesize ammonia (NH3), for fertilizer production, by combining hydrogen with nitrogen. Another major use is hydro-formulation, or high-pressure hydro-treating, of petro-... 

Joanne Vessey (fertilizer analysis). Hydro Agri (UK) Limited, Immingham Dock, UK... 

Between mergers and acquisitions, the structure of the fertilizer industry in Western Europe was spectacularly pared down. A few giants emerged to dominate the market. In France, there was CdF Chimie, later to be known as ORKEM, which had just taken a 70 percent stake in Air Liquide s subsidiary La Grande Paroisse, and Cofaz, which was taken over by Norsk Hydro in Western Germany, there was BASF and Ruhr Stickstoff in Britain, ICI and Norsk Hydro, which bought up Fisons in Italy, ANIC and Montedison s subsidiary Fertimont in Holland, DSM s UKF and Norsk Hydro NSM in Finland, Kemira, which took over both Britain s Lindsay and its Kesteven facilities. 

KOH systems have historically been used in larger-scale applications than PEM systems. Electrolyzer Corporation of Canada (now Stuart Energy) and the electrolyzer division of Norsk Hydro have built relatively large plants (100 kg/hour and larger) to meet fertilizer production needs in locations around the globe where natural gas is not available to provide hydrogen for the process. 

For years, the liquefied petroleum gas (LPG) industry has used pressurized underground liquefied gas storage. This technique has been applied to ammonia also. DuPont has operated a rock cavern in the United States with a capacity of 20 0001. Norsk Hydro has one in Norway at 50 000 t. Because of the contaminants occurring in liquid ammonia stored this way and the lack of suitable construction sites, no further storage facilities of this kind have been built for a long time. Underground fertilizer ammonia storage was planned in Russia [1310]. 

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