阅读说明：本技术 一种生产小苏打的工艺方法 (Process for producing sodium bicarbonate ) 是由 张元德 魏征 卜范厂 于 2020-05-27 设计创作，主要内容包括：本发明涉及小苏打生产技术领域,尤其涉及一种生产小苏打的工艺方法,工艺方法以重碱为原料,经过洗涤、化解、碳化处理后得到的晶浆液再经过增稠、离心、干燥、冷却处理得到小苏打产品,其中增稠以及离心处理排出的母液套用对重碱进行化解。该工艺方法可降低企业生产成本,节约能耗,降低了对设备的投资。(The invention relates to the technical field of baking soda production, in particular to a process method for producing baking soda, which uses heavy alkali as a raw material, obtains crystal slurry through washing, dissolving and carbonizing, obtains a baking soda product through thickening, centrifuging, drying and cooling, wherein mother liquor discharged through thickening and centrifuging is used for dissolving the heavy alkali. The process method can reduce the production cost of enterprises, save energy consumption and reduce the investment on equipment.)

1. The technological process of producing sodium bicarbonate features that sodium bicarbonate is first produced with sodium bicarbonate as material and through washing, decomposing, carbonizing to obtain crystal slurry, thickening, centrifuging, drying and cooling, and the mother liquid after thickening and centrifuging is used to decompose sodium bicarbonate.

2. The process for producing baking soda as claimed in claim 1, wherein said process further comprises the following steps: the heavy alkali and the mother liquor are put into an alkali dissolving barrel according to the volume ratio of 1-7:4-20, and the temperature in the alkali dissolving barrel is controlled to be 90-95 ℃.

3. The process for producing baking soda as claimed in claim 1, wherein said process further comprises the following steps: the carbonization time is 1000m³/h-1200m³Introducing kiln gas into the carbonization tower at ventilation rate of/h, wherein the liquid inlet amount of alkali liquor is 30-35m during carbonization treatment³The carbonization time is 35-45 min.

4. A process for the production of baking soda according to claim 3, characterized in that: the kiln gas is the kiln gas in the limestone calcining kiln, and the content of carbon dioxide in the kiln gas is 40%.

5. The process for producing baking soda as claimed in claim 1, wherein said process further comprises the following steps: when the reaction starts to decompose the heavy alkali, deionized water or other mother liquor discharged after carbonization treatment on a sodium bicarbonate production line can be used for decomposition.

6. The process for producing baking soda as claimed in claim 1, wherein said process further comprises the following steps: the temperature in the drying tube during the drying treatment is 135-140 ℃.

7. The process for producing baking soda as claimed in claim 1, wherein said process further comprises the following steps: during washing, the heavy alkali is placed in a centrifuge, deionized water is added, and then liquid components are removed through centrifugal separation, so that the obtained solid components are reserved.

8. The process for producing baking soda as claimed in claim 1, wherein said process further comprises the following steps: and adding deionized water to wash and separate the sodium bicarbonate crystal slurry obtained after thickening through a centrifugal machine during centrifugal treatment, and arranging an axial flow fan in an air duct of the centrifugal machine.

Technical Field

The invention relates to the technical field of baking soda production, in particular to a process method for producing baking soda.

Background

Sodium bicarbonate, an important chemical product, has been applied to various fields of life such as pharmaceutical and chemical industries. The main production methods for baking soda are mainly two types: soda synthesis and trona. Among them, the trona method is developed rapidly because of its low production cost. The market pattern of autumn is divided into two by the prior natural soda method and soda synthesis method, and the market pattern is gradually shifted to the natural soda method, so that the production cost is reduced by adopting the soda synthesis method to prepare the baking soda product. The method adopts a soda synthesis method and the main production process flow comprises the preparation and carbonization of alkali liquor, wherein the alkali liquor is prepared by taking soda as a raw material, and the alkali liquor after alkali dissolution in an alkali dissolution barrel enters a carbonization tower for carbonization, but the method has high raw material cost and more equipment investment; in addition, the alkali liquor is prepared by carbonizing sodium carbonate mother liquor obtained by wet decomposition of heavy alkali serving as a raw material in a wet decomposition tower after entering a carbonization tower. Therefore, in order to solve the above problems, it is necessary to propose a new process for producing baking soda.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the defects in the prior art, the process method for producing the baking soda is provided, and can reduce the production cost of enterprises, save energy consumption and reduce the investment on equipment.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a process for producing sodium bicarbonate uses heavy alkali as raw material, the crystal slurry obtained after washing, decomposing and carbonizing is thickened, centrifuged, dried and cooled to obtain sodium bicarbonate product, wherein mother liquor discharged from thickening and centrifuging is used for decomposing the heavy alkali.

As an improved technical scheme, the heavy alkali and the mother liquor are put into an alkali dissolving barrel according to the volume ratio of 1-7:4-20, and the temperature in the alkali dissolving barrel is controlled to be 90-95 ℃.

As an improved technical scheme, the carbonization treatment is carried out according to 1000m³/h-1200m³Introducing kiln gas into the carbonization tower at ventilation rate of/h, wherein the liquid inlet amount of alkali liquor is 30-35m during carbonization treatment³The carbonization time is 35-45 min.

As an improved technical scheme, the kiln gas is the kiln gas in the limestone calcining kiln, and the content of carbon dioxide in the kiln gas is 40%.

As an improved technical scheme, when the reaction starts to decompose the heavy alkali, deionized water or other mother liquor discharged after carbonization treatment on a sodium bicarbonate production line can be used for decomposition.

As an improved technical proposal, the temperature in the drying tube is 135-140 ℃ during the drying treatment.

As an improved technical scheme, during washing, the heavy alkali is placed in a centrifuge, deionized water is added, and then liquid components are removed through centrifugal separation, and obtained solid components are reserved.

As an improved technical scheme, deionized water is added into baking soda crystal slurry obtained after thickening treatment and washed and separated by a centrifugal machine during centrifugal treatment, and an axial flow fan is arranged in an air duct of the centrifugal machine.

After the technical scheme is adopted, the invention has the beneficial effects that:

(1) the process method of the invention takes the heavy alkali as the raw material, saves the consumption of a plurality of production procedures such as subsequent calcination and the like compared with the method taking the pure alkali as the production raw material, and greatly reduces the cost of the raw material; compared with the heavy alkali wet decomposition process, the wet decomposition operation is omitted, the energy consumption is avoided, the production cost of enterprises is reduced, and the baking soda product under the process condition of the invention reaches the industrial first-grade standard.

(2) By adopting the process method, the operation period of the carbonization tower can reach 150 hours at most, the alkali dissolving barrel and the pipeline can normally operate for 30 days without abnormity, the frequency of boiling the carbonization tower and the alkali dissolving barrel is reduced, the steam consumption is saved, the production fluctuation is reduced, and the steam consumption can be saved by about 0.142 t/ton of sodium bicarbonate.

(3) By adopting the process method, equipment such as a finished product lye pump, a clarifying barrel and the like are not needed, so that the equipment investment is reduced; meanwhile, the process flow is simple, the electricity can be saved by about 43.24 ten thousand KW.h per year, and the electricity can be saved by 3.672KW.h per ton of baking soda.

(4) The invention adopts the kiln gas in the limestone calcining kiln to provide carbon dioxide gas during carbonization treatment, because the part of the kiln gas is the surplus kiln gas on the soda production line, if the kiln gas is directly discharged, the resource waste can be caused, and the cost is saved by directly adopting the part of the kiln gas.

(5) The heavy alkali is firstly centrifugally washed by a centrifuge before being decomposed, so that the content of ammonium bicarbonate and the content of salt in the heavy alkali can be reduced.

(6) During centrifugal treatment of baking soda crystal slurry obtained after thickening treatment, deionized water is added, washing and separation are carried out through a centrifugal machine, and an axial flow fan is arranged in an air duct of the centrifugal machine; the baking soda crystal slurry in the centrifuge can be washed by adding deionized water to remove some water-soluble impurities, and ammonia gas in the baking soda crystal slurry can be removed by arranging an axial flow fan in an air duct of the centrifuge, so that the product quality can be further improved.

Drawings

FIG. 1 is a process flow diagram of a process for producing baking soda according to the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.