59 results about "Solvay process" patented technology

A method of producing soda ash and ammonium sulphate by recycling by-products of Merseberg and Solvay processes includes treating brine with soda ash distiller waste for desulphatation of the brine to obtain gypsum, recovering pure salt from the desulphated brine and utilizing it in manufacture of soda ash in a Solvay process, washing the gypsum and reacting it with liquor ammonia and carbon dioxide to obtain CaCO3 and ammonium sulphate, separating the CaCO3 from the ammonium sulphate solution and recovering solid ammonium sulphate, washing the CaCO3 followed by calcination to generate CO2 and lime, recycling the CO2 in the Solvay process to obtain soda ash, recycling the lime with ammonium chloride generated in the Solvay process to recover ammonia and obtain distiller waste containing CaCl2 as a by-product, recycling the by-product distiller waste for the desulphatation of the brine, and recycling the ammonia recovered.

The invention provides an improved method for producing low-salt high-quality dense soda ash by using light soda ash produced by a hot method alkali combination process as a raw material. The method comprises the following steps: firstly, producing the light soda ash containing 0.5 to 0.9 percent of NaCl in mass fraction through hot method alkali combination; and secondly, producing the low-salt high-quality dense soda ash containing less than 0.3 percent of the NaCl in mass fraction by adopting a liquid-phase hydration method or a modified solid-phase hydration method, wherein in order to ensure the salinity in the product, a certain amount of saliferous mother liquor of 40 to 80 g / L is needed to be discharged from a hydration system continuously or discontinuously and the saliferous soda mother liquor is sent back into a brine refining system, a Na2CO3 component in the mother liquor serves as a calcium remover, and a NaCl component serves as a raw material component. The method overcomes the defects that an ammonia soda process for producing the low-salt dense soda ash has a large sewage discharge and a combination soda production method cannot normally produce the low-salt dense soda ash; the raw materials can be coarse sea salts and mine salts, or bitterns obtained through solution mining of salt mines can be used directly; and the method has the advantages of no sewage discharge, good product quality and extensive development prospect.

The invention discloses a method used for pyrolyzing wet oxidation desulfurization mixed waste liquid in partial oxidation environment. According to the method, a desulfurization waste liquid mixture obtained via ammonia alkaline method and sodium alkali method is filtered; an obtained filtrate is subjected to reduced pressure vaporization preheating, a desulfurization waste liquid concentrated solution obtained via vaporization is subjected to pressurization, is subjected to atomization using a three-channel combined pressure atomization nozzle, and then is delivered into a pyrolysis reactor together with hydrogen-rich gas, such as coal gas, and oxygen for pyrolysis; pyrolysis gas obtained via pyrolysis is subjected to vaporization preheating of desulfurization waste liquid via a direct method or an indirect method; pyrolyzed molten salt obtained via pyrolysis is discharged via the bottom of the pyrolysis reactor, is cooled using a cooling system, and then is recycled back to a desulfurization workshop section to provide alkali sources. The method is simple; operation is continuous and stable; application range is wide; desulfurization waste liquid obtained via ammonia alkaline method and sodium alkali method, and a mixture of desulfurization waste liquid obtained via ammonia alkaline method and sodium alkali method can be processed effectively; all-component harmless treatment of waste liquid is realized, and problems that mixed waste liquid is difficult to process, processing processes are complicated, and application range is limited, are solved completely.