SU1062191A1 - Method for treating limestone - Google Patents

Abstract

BULK TREATMENT DREAMS by moistening it with a liquid mineralizer and roasting, characterized in that, in order to increase the degree of roasting and reduce harmful emissions into the environment, a mixture of chloride sublimates and pulp of gas purification of titanium production in hypochlorite pulps of magnesium production is used as a mineralizer -2.5% by weight of limestone. (L

Description

and ISD

The invention relates to the production of lime and is aimed at protecting the environment, increasing the integrated use of chloride waste from titanium-magnesium production. The formation of large quantities of chloride wastes in titanium-magnesium production requires significant costs for their disposal. However, chloride wastes, having a negative impact on the environment, can also be beneficial if they are used in accordance with their properties. A known method for producing lime involves moistening lime with a solution of hydrochloric acid in an amount of 0.05-0.9% and calcining Cl3. The disadvantage of this method is the relatively complex instrumentation of the process associated with the need to use acid-resistant materials for storing and transporting acid. In addition, commercial (purchased) reagent, hydrochloric acid mineralizer, is used. The closest in technical essence to the present invention is a method of processing lime with the use of calcium chloride as a mineralizer. Pre-calcination of a porous carbonate raw material with calcium chloride solution at the rate of adding 0.5-1.0% calcium chloride, based on the weight of the calcined material G2, is especially effective. The disadvantage of the known method is the low degree of calcification of limestone that reaches only 75.0. % The purpose of the invention is to increase the degree of firing and reduce harmful emissions into the environment. The goal is achieved by the fact that according to the method of processing lime by moistening it with a liquid mineralizer and roasting, a mixture of chloride sublimates and pulps of gas purification of titanium production, hypochlorite pulps of magnesium production in the amount of 1-2.5% by weight of lime is used as mineralizer. Chloride waste from titanium-magnesium production (sublimates and pulps of gas purification of titanium production), decomposed (unconditioned) and undecomposed hypochlorite pulp of magnesium production are liquid and solid products whose chemical composition is presented in Table 1. Table

Chloride sublimates Tver-0.5-2.22.0-7.0 titanium proiepro-9, 0 30.0 18.0 of the plant. duct

The content of components, g / l

CaCO Ca (CEOj 1 MgCeJ КСе САС «2 ТЮ .CFe (ОNYLE (OH) j

Cao

18.0- 10.0- 3.0 Liquid; 20.0 12.0 4.0 product

Decomposed g to To e 18.0-11.0-7.0rit magnesium pulp produced20.0 13.0 9.0

Liquid chloride waste (hypochlorite pulp before and after decomposition, spent lime gas cleaning pulp) can be used as a mineralizer during calcination of lime without preliminary preparation.

0.7-- 0.5-120.0 1, 2 1.0 150.0

0.5-0.7 210.01, 4 1.0 230.0 Solid chloride oTxoj№i {sublimates of titanium production) as a mineralizer require preliminary preparation. Such preparation consists of mixing them with liquid chloride wastes in a ratio of 1: 5-10. This results in 0.5- L0-1.0-1.11, 0 2.5 2.5 0.5,

pulp of the following composition: 150–300 g / l of metal chloride salts (ba, Mg, Ml, Cr, Ti, Y, Fe, etc.) and 50120 g / l of solid suspensions of hydroxides, oxides and oxychlorides of the same metals,

When using the complex mineralizer during calcination of limestone in the amount of 0.5%, the degree of calcination of limestone is 70.1%. This is lower than in the known method at the same concentration.

Moistening limestone with a mineralizer in the amount of 2.5% gives a high degree of roasting - 99.1%. A further increase in the amount of added mineralizer is not advisable, since the degree of calcination does not increase.

The proposed method is carried out as follows.

Solid chloride waste from titanium production is mixed with liquid waste in a ratio of 1: 5-10. Thus prepared or obtained in the manufacture of titanium and

; magnesium liquid waste is transported to the limestone burning area in a special tank, from which it is pumped through a pipeline to

a spraying device installed by the treated limestone. The mineralizer is sprayed (or otherwise) onto the surface of limestone on

the stock after crushing limestone or before loading crushed limestone into a kiln. Firing lead in a known manner.

Example 1. It is known to be treated with a solution of calcium chloride in an amount of 0.5-1.0% according to a known method. Tia treated in a manner known to be calcined in a laboratory muffle furnace at 800 ° C

5 for 1. h. The calcining results presented in Table 2 show that the degree of calcination of limestone is only 71-75%.

Example 2. It is known to process liquid mineralizers, namely: a mixture of titanium production sublimates of chloride and decomposed hypochlorite pulp (); hypochlorite pulp before decomposition;

5 hypochlorite pulp after decomposition.

The mineralizer is used in the amount of 1.0-2.5%. The results of firing are presented in table 2.

table 2

Claims (1)

METHOD FOR TREATING Limestone by wetting it with a liquid mineralizer and firing, characterized in that, in order to increase the degree of firing and reduce harmful emissions into the environment, a mixture of chloride sublimates and pulp from gas treatment of titanium production, hypochlorite pulps of magnesium production in the amount of 1 is used as a mineralizer -2.5% by weight of limestone.