CN1116184A

CN1116184A - Solid phase hydration method for producing low salt heavy quality pure alkali

Info

Publication number: CN1116184A
Application number: CN 94107937
Authority: CN
Inventors: 戎寿昌; 吴邦宁
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-08-04
Filing date: 1994-08-04
Publication date: 1996-02-07

Abstract

Said method is that common light pure alkali is hydrated with 25-30% of water, then making centrifugal separation in centrifuge, crystal-water sodium carbonate is dried, the mother solution is dried after recrystallizing and centrifugal separation, the product of low salt and heavy quality pure alkali is obtained. Said method can reduce salt content by over 50%.

Description

A kind of solid phase hydration process of producing low-salt dense soda ash

The present invention relates to a kind of production method of soda ash, particularly relate to a kind of method of producing low-salt dense soda ash by common Soda Ash Light 99.2min. solid phase hydration.

Traditional method with common Soda Ash Light 99.2min. production Soda Ash Danse has two kinds.One is that liquid phase water is legal: add entry and make into saturated solution with Soda Ash Light 99.2min. in the hydrator that band stirs, Crystallization Separation goes out monohydrated sodium carbonate, becomes less salt part Soda Ash Danse through dehydration.This method scabs owing to producing in the crystallisation process, and is extremely difficult, need expend in a large number manually, and operation rate is low, is difficult to maximization, serialization, and mother liquor is handled also difficult.

Another kind method is to need water gaging to add in the rotary type hydration machine Soda Ash Light 99.2min. and theory, generates monohydrated sodium carbonate under solid state shape, gets product behind the drying and dehydrating.Though this method has solved maximization, the serialization problem of equipment, the product saltiness is basic identical with the raw material Soda Ash Light 99.2min., second-rate, can not satisfy the requirement that high-quality product is produced.

For solving the deficiency of above traditional method, the present invention adopts the centrifugation solid phase hydration process to produce low-salt dense soda ash, the maximization that helps producing, serialization, and can obtain to be suitable for the high-quality soda ash of high quality of production.

The present invention is not have in the slick rotary type hydration machine of any member the common Soda Ash Light 99.2min. of adding in inside and is that the water that manys generates monohydrated sodium carbonate under 90 ℃ of conditions than theoretical requirement, this monohydrated sodium carbonate goes out the whizzer that enters band center distribution device behind the hydration machine at once and filters, isolate the higher mother liquor of saliferous, monohydrated sodium carbonate enters calcining furnace (being drying oven) dehydration and becomes the product low-salt high-quality dense soda ash; Separate the higher mother liquor of saliferous and through evaporation monohydrated sodium carbonate is crystallized out in a small-sized evaporative crystallizer, the monohydrated sodium carbonate that whizzer is separated after centrifugation and hydration enters calcining furnace in the lump again, and dehydrating becomes product.Quantity separation mother liquor seldom is the higher sodium carbonate solution of saltiness, can be sent to salt refining workshop recovery salt and alkali wherein for solvay soda process factory; For connection alkaline process factory, can be sent to the mother liquor II system after II process ammonium chloride crystals separates, to reclaim salt and alkali wherein.

Raw material Soda Ash Light 99.2min. major ingredient is anhydrous sodium carbonate (sodium chloride-containing 0.5-0.7%), during hydration owing to added excessive water (water yield 25-30%, theoretical amount 17%), therefore only the water of some becomes crystal water (generation monohydrated sodium carbonate), and remaining is a unbound state; Then dissolved whole sodium-chlor that Soda Ash Light 99.2min. brings in the free-water, when centrifuge dehydration, mainly sloughed free-water, salt wherein (sodium-chlor) also just along with being removed by centrifugal, reaches the effect of desalination, finally obtains low-salt dense soda ash.The mother liquor that centrifugation for the first time goes out also contains a small amount of yellow soda ash, again through centrifugation, can reach higher product yield behind the recrystallization.

For obtaining the product of different saltiness, can be at whizzer water spray washing monohydrated sodium carbonate, to satisfy the requirement of different user.

The present invention adopts the centrifugation solid phase hydration process to produce low-salt dense soda ash, in traditional method, introduce operations such as centrifugation, maximization, the serialization of producing have been realized, the product sodium chloride content is lower than 0.3%, saltiness reduces more than 50% than traditional method, can satisfy the requirement that high-quality product is produced, and the mother liquor processing is easy, three-waste free pollution.

Embodiment:

Get 1Kg Soda Ash Light 99.2min. (containing NaCl0.7%), add 300gH ₂O, hydration in hydration machine (90 ℃ of temperature) 30 minutes generates monohydrated sodium carbonate, enters whizzer, and after 15 seconds of centrifuging, the crystal monohydrated sodium carbonate enters kiln dried, 150 ℃ of kiln temperatures; Mother liquid obtained again through recrystallization, the same drying of crystal after the centrifugation gets product low-salt high-quality dense soda ash 0.91Kg at last, and recording wherein, NaCl content is 0.25%.

Claims

1. solid phase hydration process of producing low-salt dense soda ash, generate monohydrated sodium carbonate by common Soda Ash Light 99.2min. hydration, add excessive water when it is characterized in that hydration, generate monohydrated sodium carbonate after centrifuging, isolate the higher mother liquor of salt concentration, the monohydrated sodium carbonate drying gets product.

2. the method for claim 1, wherein isolated mother liquor makes monohydrated sodium carbonate crystallize out in vaporizer, and the monohydrated sodium carbonate that centrifugation is come out after centrifugation and hydration in the lump drying get product.

3. method as claimed in claim 1 or 2 is characterized in that at whizzer water spray washing monohydrated sodium carbonate.