Recovery ammonia product

Chevron s WWT (wastewater treatment) process treats refinery sour water for reuse, producing ammonia and hydrogen sulfide [7783-06-04] as by-products (100). Degassed sour water is fed to the first of two strippers. Here hydrogen sulfide is stripped overhead while water and ammonia flow out the column bottoms. The bottoms from the first stripper is fed to the second stripper which produces ammonia as the overhead product. The gaseous ammonia is next treated for hydrogen sulfide and water removal, compressed, and further purified. Ammonia recovery options include anhydrous Hquid ammonia, aqueous Hquid ammonia, and ammonia vapor for incineration. There are more than 20 reported units in operation, the aimual production of ammonia from this process is about 200,000 t. 

Other small amounts are obtained from coke burning, the calcination of lime, in the manufacture of sodium phosphates from soda ash and phosphoric acid, by recovery from synthesis gas in ammonia production, recovery as a by-product in the production of substitute natural gas, and recovery from natural wells. 

A) Synthesis loop for pure and dry makeup gas B) Product recovery after recycle compression C) Product recovery before recycle compression (four-nozzle compressor design) D) Two stages of product condensation a) Ammonia converter with heat exchangers b) Ammonia recovery by chilling and condensation c) Ammonia recovery by condensation at ambient temperature d) Synthesis gas compressor e) Recycle compressor... 

Hydrogen and Carbon Dioxide Production from Steam-Methane Reformer Off Gas Production of Ammonia Synthesis Gas Hydrogen Recovery fiom Refinery Off Gases Methane-Carbon Dioxide Separation from Landfill Gas... 

If the retort water is considered for domestic or irrigation uses, it would have to be treated to remove a number of contaminants. Of the major constituents in retort water, the NH4, HCOa", and organic compounds in the water clearly make it unsuitable for other uses (18). Of the trace constituents, the arsenic and selenium concentrations listed in Table IV are above the maximum permissible concentrations for drinking water (36). The boron concentration may make water unsuitable for irrigation (22). Other studies have found silver and lead concentrations in retort waters have exceeded the maximum permissible concentrations for drinking water (1,2,36). Numerous studies for the treatment of the retort water have been initiated (37). The objectives of these studies are usually to find a method to recover the ammonia and organic material from the water so that treatment costs will be lowered through by-product recovery. 

FIGURE I 1.4 Simplified flowsheet of the gas recycle and product recovery systems for ammonia synthesis, from the gas mixture leaving the converter. 

Bones and teeth dissolve in acid. The insoluble calcium monophosphate salt, from which hydroxyapatite is made, is converted to the more soluble calcium dihydrogen phosphate salt in an environment whose pH is less than 6.2 (Sect. 9.1.1). The severity of caries was related to the pH produced in dental biofilms (plaques) after ingesting sucrose and other sugars by Richard M Stephan. The pH response he identified is referred to as Stephan Curve. He found that the starting pH, the extent of its drop, and the time for recovery to the starting pH were all related to caries severity. The pH drop was later associated with lactic acid production due to bacterial carbohydrate fermentation (saccharolytic fermentation, Sect. 1.3.2). The subsequent rise in pH was due to the production of ammonia by bacterial... 

Carbon dioxide-methane separation Solvent vapor recovery Hydrogen and carbon dioxide recovery from steam-methane reformer off-gas Hydrogen recovery from refinery off-gas Carbon monoxide-hydrogen separation Alcohol dehydration Production of ammonia synthesis gas Normal-isoparaffin separation Ozone enrichment... 

The thermodynamic energy requirement is 2 x lO" kJ/t NH3, which represents the theoretical minimum for all conceivable processes. Modern processes for the production of ammonia from natural gas have energy consumptions of around 3x10 kJ/t NH3, i.e., only 1.5 times the theoretical minimum energy consumption. Today much of the energy requirement can be covered by means of heat recovery. Modern ammonia plants produce up to 2000 t/d. 

There have been no signiflcant catalyst advances for methane ammoxidation since the disclosure of the Pt/Rh catalyst by Andrussow in the 1930s (112). Advances in the technology have been in the areas of process operability process safety, especially pertaining to handling of potentially flammable and explosive hydrocarbon/oxygen gas mixtures and in product recovery and ammonia recycle. Because of its many years of safe and dependable operation and its use of low cost natural gas feedstock, the Andrussow process remains the dominant technology for the commercial manufacture of HCN. 

Ammonia synthesis process with product recovery by water absorption, with recycling of unreacted gas after drying by solid adsorbent or with liquid aqueous ammonia. A. Pinto Qniperial Chemical Industries Ltd). EP1324 (1979) US 4242317 (1981). 

Higher hydrogen recovery in the production of ammonia synthesis gas. A. Pinto (Imperial Chemical Industries Ltd). US 4725380 (1988). 

Product Recovery from Ammonia Synthesis Loops.253... 

The ratio of reactants had to be controlled very closely to suppress these impurities. Recovery of the acrylamide product from the acid process was the most expensive and difficult part of the process. Large scale production depended on two different methods. If soHd crystalline monomer was desired, the acrylamide sulfate was neutralized with ammonia to yield ammonium sulfate. The acrylamide crystallized on cooling, leaving ammonium sulfate, which had to be disposed of in some way. The second method of purification involved ion exclusion (68), which utilized a sulfonic acid ion-exchange resin and produced a dilute solution of acrylamide in water. A dilute sulfuric acid waste stream was again produced, and, in either case, the waste stream represented a... 

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