CN101327940A - Process for preparing solar salt from purified saturated bittern as raw material - Google Patents

Abstract

The invention adopts moderate brine (11 DEG Be) after bromine extraction and kalium extraction as material, wherein equivalent waste slag electric limes produced by chlor-alkali plants are added. The reaction condition is controlled and the mixture is continuously distilled to 23 DEG Be after the extraction of magnesium hydroxide, Ca<2+> is removed by adding glauber salt and soda, the mixture after above treatment is used as material brine to prepare industrial salts. After all the above treatment Ca<2+> content reduces 94.29%, Mg<2+> content reduces 99.02%, SO4<2-> reduces 85.57%, because the brine component changes, the brine evaporation impedance is reduced, the output and quality of the sea salt are improved, the bittern chemical production technique is simplified. The technology of the invention has larger application value and wide application prospect during the transformation process of salt chemical production from the bittern chemical industry to sea water chemical industry.

Description

A kind of utilization purifies the back saturated bittern and produces Exposure to Sunlight salt technology for raw material

Technical field

Salt producing craft

Background technology

In existing Salt production, taking nature seawater is raw material, progressively is concentrated into saturated bittern through sun power and wind energy effect, continues evaporation then sodium chloride crystal is separated out.The calcium magnesium plasma that exists in the seawater belongs to foreign ion in Salt production, the evaporative resistance that not only can increase bittern reduces the output of sea salt, is adsorbed on the sodium chloride crystal surface when the sodium-chlor crystallization is separated out again, reduces the sea salt quality.

Summary of the invention

In order to address the above problem, the moderate bittern that the present invention adopts and carries bromine, carries behind the potassium is raw material, equivalent adds the waste residue Calcium Carbide Ash that chlor-alkali plant is produced, the control reaction conditions, extract magnesium hydroxide, continue to be evaporated to calcium sulfate and separate out, only contain components such as sodium-chlor, Repone K and a small amount of sodium sulfate in the bittern, utilize it then as raw brine manufacture salt.Because the bittern composition changes, sea salt output, quality are improved, and have improved existing salt producing craft.

Fig. 1 is seen in concrete technical process of the present invention, comprises following a few step:

(1) receives and get seawater: utilize water pump that raw material seawater (3.5 ° of B é) is drawn and raise to elementary system halogen district;

(2) evaporation concentration: seawater progressively is concentrated into 11 ° of B é from elementary system halogen district to middle rank system halogen district;

(3) extract magnesium hydroxide: during 11 ° of B é of bittern concentration left and right sides, according to reaction principle, the Calcium Carbide Ash waste residue (main component is a calcium hydroxide) of selected chlor-alkali plant is as the Mg in the basic raw material removal bittern ²⁺, make Mg ²⁺Separate out with the magnesium hydroxide form;

(4) remove calcium ion: when bittern concentration reaches 23 ° of B é, add saltcake and remove Ca ²⁺, remaining Ca ²⁺Available a spot of yellow soda ash is removed, and only contain sodium-chlor and components such as a spot of Repone K, sodium sulfate in the bittern this moment.

Claims (3)

1, a kind of novel salt manufacturing bittern-purified brine, contained main component is a sodium-chlor, is the part of bittern comprehensive utilization.

2, according to the described purified brine of claim 1, it is characterized in that: bittern is through carrying potassium, carry bromine, carrying magnesium, removes the solution behind calcium and the sulfate radical.

3, a kind of novel bittern salt producing craft, its practical application may further comprise the steps:

(1) receives and get seawater: utilize water pump that raw material seawater (3.5 ° of B é) is drawn and raise to elementary system halogen district;

(2) evaporation concentration: seawater progressively is concentrated into 11 ° of B é from elementary system halogen district to middle rank system halogen district;

(3) extract magnesium hydroxide: during 11 ° of B é of bittern concentration left and right sides, according to reaction principle, the Calcium Carbide Ash waste residue (main component is a calcium hydroxide) of selected chlor-alkali plant is as the Mg in the basic raw material removal bittern ²⁺, make Mg ²⁺Separate out with the magnesium hydroxide form;

(4) remove calcium ion: when bittern concentration reaches 23 ° of B é, add saltcake and remove Ca ²⁺, remaining Ca ²⁺Available a spot of yellow soda ash is removed, and only contain sodium-chlor and components such as a spot of Repone K, sodium sulfate in the bittern this moment.

(5) purify back saturated bittern salt manufacturing: it is saturated that the bittern after will purifying according to Exposure to Sunlight salt technology continues to be concentrated into sodium-chlor, and saturated bittern continues the crystallization of evaporation sodium-chlor separates out, and receives the salt operation when bittern reaches 28 ° of B é.

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