Method for preparing chlorine-removal alkali residue mixture by utilizing alkali residues through ammonia-soda process and application of chlorine-removal alkali residue mixture

Abstract

The invention discloses a method for preparing a chlorine-removal alkali residue mixture by utilizing alkali residues through an ammonia-soda process. The method comprises the following steps: step 1, crushing returned sand and returned stones, and grinding to obtain returned sand and returned stone powder; step 2, soaking the returned sand and returned stone powder in water for 0.5-14 days, digesting overburnt calcium oxide, mixing the digested returned sand and returned stone powder, alkali residues and water, wherein a ratio of dry mass of the digested returned sand and returned stone powder to the alkali residues is 2:8 to 5:5 based on the mass percentage of the materials, and the total mass of the water is 1.5 to 8 times that of total dry mass of the digested returned sand and returned stone powder and alkali residues; or mixing the returned sand and returned stone powder, the alkali residues and water, soaking the mixture for 0.5-14 days, and digesting the overburnt calcium oxide; and step 3, performing filter pressing treatment, thereby obtaining the chlorine-removal alkali residue mixture of which the chloride ion content is lower than 0.30 percent of the total mass of solids in the mixture. The invention also discloses application of the chlorine-removal alkali residue mixture. The method and application disclosed by the invention are good in chlorine removal effect, simple in process, energy-saving and environmentally friendly.

Description

technical field [0001] The invention belongs to the field of industrial solid waste treatment, in particular to a method for treating alkali slag and returning sand and stone by ammonia-soda method and an application method thereof. Background technique [0002] As a basic chemical raw material, soda ash is mainly used in building materials, chemical industry, chemical pesticides, non-ferrous metals, textiles and other industries. It occupies an important position in the national economy and is known as the "mother of chemical industry". At present, soda ash production mainly includes trona method, ammonia soda method and combined soda method. The soda ash production in my country is mainly based on ammonia soda method. [0003] Alkali slag is industrial waste produced during the production of soda ash by ammonia-soda method. The main components of alkali slag are calcium carbonate, calcium sulfate, aluminum, iron, silicon and other oxides, and contain a large amount of chlo...

AI Technical Summary

Problems solved by technology

Its main component is calcium carbonate. Because it contains percalcined calcium oxide, it has been used for road paving and shaft kiln cement raw materials for a long time. Although its use value is low, most of it can be consumed

However, with the improvement of road quality requirements and the elimination of shaft kiln cement plants, its utilization rate has declined instead, and it is urgent to find new ways of utilization