1 through the compressed carbon dioxide into the concentrated aqueous ammonia, carbon dioxide and placed under pressure, and cooled, precipitated crystals were separated by centrifugation, from dehydration. When purification was dissolved in water, ethanol was added, so that recrystallization.
(2) After carbonization absorbing ammonia water, carbonation with carbon dioxide, and then separated and dried to obtain ammonium bicarbonate. The chemical reaction equation:
NH3 + CO2 + H2O → NH4HCO3
3 from lime and washed purified CO2 gas, which leads to ammonia to make it saturated after separation by centrifugation, hot air drying derived products. [4]
4 Typical small nitrogenous fertilizer plant to produce ammonium bicarbonate anthracite as raw material, preparation of semi-water gas, which after removal of hydrogen sulfide into the pressurized shift reaction system, resulting nitrogen, hydrogen and carbon dioxide mixture into the carbonation tower, In this concentration of carbon dioxide and about 17% aqueous ammonia, ammonium bicarbonate crystals separated by a centrifuge to obtain ammonium bicarbonate products. Removal of carbon dioxide feed gas, after further removal of a small amount of residual carbon dioxide and carbon monoxide into the ammonia synthesis systems. Dried at room temperature, ammonium bicarbonate, a certain stability and good flowability. Some Chinese bicarbonate plant using air-drying method to product drying; adding more plants using crystallization modifiers way to make ammonium bicarbonate crystals grow relatively thick, solid liquid separation so as to improve the operating conditions, so from 5% moisture content of product ~ 5.5% decrease 3.5% to 2.5%, and reducing the loss of decomposition products of the agglomeration have a significant effect. [3]
Production of ammonium bicarbonate reaction is:
NH3 + H2O → NH3 * H2O + heat NH3 · H2O + CO2 → NH4HCO3 + heat.
