What are the benefits of ammonia alkali soda ash method

He summarized the advantages and disadvantages of the Solvay method, and believed that the main disadvantage of this method is that only half of the two raw material components are used, that is, sodium in salt (NaC1) and carbonate in lime (CaCO3) are combined to form soda ash (NaCO3), and the other half of the components are chlorine in salt and calcium in lime are combined to form CaCl2, but there is no use.

In view of the insurmountable defects in the above production, Hou Debang creatively designed a new process of combined alkali production. This new process is to build an ammonia plant and an alkali plant together for joint production. The ammonia plant supplies the ammonia and carbon dioxide needed by the alkali plant.

The ammonium chloride in the mother liquor is crystallized by adding table salt to it as a chemical product or fertilizer. The salt solution can also be recycled.

In order to realize this design, in the harsh environment of the Anti-Japanese War from 1941 to 1943, under the strict guidance of Hou Debang, after more than 500 cycle tests and more than 2,000 samples, the specific process flow was determined, and this new process made the salt utilization rate increase from 70 to 96 at once, and also converted the original useless calcium chloride into fertilizer ammonium chloride, which solved the problem of calcium chloride occupying land and destroying fields and polluting the environment. This method has pushed the world's alkali production technology to a new height and won high praise from the international chemical industry. In 1943, the Chinese Society of Chemical Engineers unanimously agreed to name this new joint alkali production method as "Hou's combined alkali production method".

The advantages of this method: the advantages of the ammonia-alkali method are retained, its shortcomings are eliminated, and the utilization rate of salt is increased to 96; NH4Cl can be used as nitrogen fertilizer; It can be combined with the ammonia plant to convert the raw gas CO of synthetic ammonia into CO2, eliminating the process of making CO2 from CACO3.

There are the following benefits.

The CO2 generated by the reaction can be reused, and NH4Cl can be reacted with quicklime to produce NH3 and be reused as a raw material.

2NH4Cl + CAO===2NH3 + CACl2+H2O ammonia-alkali method enables continuous production The utilization rate of salt is improved, and the product quality is pure, so it is called soda ash But the biggest advantage is that the cost is low.

Ammonia-alkali method (also known as Solvay method).

It is a soda ash production method invented by the Belgian engineer Survay (1838 1922) in 1892. He uses salt (sodium chloride), limestone (calcined to produce quicklime and carbon dioxide), and ammonia as raw materials to produce soda ash. Ammonia gas is first introduced into saturated salt water to form ammonia brine, and then carbon dioxide is introduced to form sodium bicarbonate precipitate and ammonium chloride solution with less solubility.

The chemical reaction principle is: NaCl NH3 H2O CO2 NaHCO3 NH4Cl

The NaHCO3 microcrystals obtained by filtration and washing are then heated and calcined to obtain soda ash products. The carbon dioxide gas emitted by 2NAHC3 NA2CO3 H2O CO2 can be recycled. The filtrate containing ammonium chloride is mixed with lime milk [Ca(OH)2] and heated, and the ammonia gas released can be recycled.

cao＋h2o＝ca(oh)2，2nh4cl＋ca(oh)2＝cacl2＋2nh3↑＋2h2o

Sodium carbonate uses are as follows:

1. The glass industry is the largest consumption department of soda ash, and it consumes soda ash per ton of glass. It is mainly used for float glass, picture tube glass shell, DAO optical glass, etc.

2. It can also be used in other departments such as chemical industry and metallurgy. The use of heavy soda ash can reduce the flying of alkali dust, reduce the consumption of raw materials, improve labor conditions, and also improve product quality, while reducing the erosive effect of alkali powder on refractory materials and prolonging the service life of the kiln.

3. As a buffer, neutralizer and dough improver, it can be used for pastries and flour foods, and can be used in an appropriate amount according to production needs.

4. As a detergent for wool rinsing, bath salts and medicine, alkaline agent in tanning.

5. Used in the food industry as a neutralizer and leavening agent, such as the manufacture of amino acids, soy sauce and flour foods such as steamed bread and bread. It can also be mixed into alkaline water to be added to pasta to increase elasticity and ductility. Sodium carbonate can also be used in the production of monosodium glutamate.

It is one of the important chemical raw materials, used in the preparation of chemicals, cleaning agents, detergents, and also used in photography and medicine.

The vast majority is used in industry, and a small part is for civilian use. In industrial soda ash, mainly light industry, building materials, chemical industry, accounting for about 2 3;This is followed by metallurgy, textile, petroleum, national defense, medicine and other industries. The glass industry is the largest consumer of soda ash, consuming tons of soda ash per ton of glass.

In the chemical industry, it is used in water glass, sodium dichromate, sodium nitrate, sodium fluoride, baking soda, borax, trisodium phosphate, etc. In the metallurgical industry, it is used as a flux for smelting and flotation agent for mineral processing, and for steelmaking and antimony smelting, it is used as a desulfurizer. It is used as a water softener in the printing and dyeing industry.

The tanning industry is used for the degreasing of raw hides, neutralizing chrome tanning and increasing the alkalinity of chrome tanning liquid. It is also used in the production of synthetic detergent additives, sodium tripolyphosphate and other sodium phosphate salts. Edible grade soda ash is used in the production of monosodium glutamate, pasta, etc.

Prohibited substances] strong acid, aluminum, fluorine.

In many places, glass, chemical, building materials, printing, daily chemical, bubble alkali, bentonite and other industries can be used, as raw materials and detergents.

Rapid neutralization of acidic waste liquid, commonly used in industry, with soda ash.

The use of soda ash is mainly used in the glass industry, chemical industry, measuring datum, food industry, etc.

1. Glass industry.

The glass industry is the largest consumer of soda ash**, consuming soda ash per ton of glass. It is mainly used for float glass, picture tube glass shell, optical glass rotten, etc.

2. Chemical industry.

In the chemical industry, it is mainly used to prepare sodium salts, metal carbonates, baking soda, sodium nitrate, sodium nitrite, sodium silicate, borax, bleach, fillers, detergents, catalysts and dyes.

3. Measurement datum.

Benchmark for calibration of acids in quantitative analysis, determination of aluminum, sulfur, copper, lead and zinc. Urine and whole blood glucose are tested. Analysis of co-solvents for silica in cement. metallographic analysis of metals, etc.

4. Food industry.

In the food industry, it is used as a neutralizer and leavening agent, such as the manufacture of amino acids, soy sauce and flour foods such as steamed bread and bread. It can also be mixed into alkaline water to be added to pasta to increase elasticity and ductility. Zhongli Qing can also be used to produce monosodium glutamate.

The properties of soda ash sodium carbonate are sold on land

1. Solubility.

Sodium carbonate is easily soluble in water and glycerol. 20 per 100 grams of water can dissolve 20 grams of sodium carbonate, when the solubility is the largest, 100 grams of water can be dissolved gram of sodium carbonate, slightly soluble in absolute ethanol, insoluble in propanol. The solution is alkaline and can make phenolphthalein red.

2. Stability.

It is more stable, but it can also decompose at high temperatures to produce sodium oxide and carbon dioxide.

3. Hydrolysis reaction.

Due to the hydrolysis of sodium carbonate in aqueous solution, the ionized carbonate ions combine with the hydrogen ions in the water to form bicarbonate ions, resulting in the reduction of hydrogen ions in the solution, leaving ionized hydroxide ions, so the pH of the solution is alkaline.

The above content refers to Encyclopedia - Sodium Carbonate.

The chemical reaction principle of ammonia-alkali method to produce soda ash is to react ammonia and carbon dioxide with sodium chloride and water to produce sodium bicarbonate, and then heat sodium bicarbonate to produce sodium carbonate; Ammonia dissolved in water is alkaline and absorbs carbon dioxide more easily than water; At a certain temperature, the solubility of ammonium bicarbonate is smaller than that of ammonium chloride, so ammonium bicarbonate can be precipitated from the solution first

Therefore, the answer is: NH3+CO2+H2O+NaCl NAHCo3+NH4Cl;

2nahco3

na2co3+co2↑+h2o．