阅读说明：本技术 一种七水硫酸镁的连续反应工艺及连续反应设备 (Continuous reaction process and continuous reaction equipment for magnesium sulfate heptahydrate ) 是由 田雨 于 2021-08-05 设计创作，主要内容包括：本发明公开了一种七水硫酸镁的连续反应工艺,包括：(1)使用高速剪切的固液混合器作为反应器,在固液混合器内同时加入水和/或母液,以及50％～98％浓度的硫酸和氧化镁粉；(2)在反应过程中,通过反应器的温控设备进行冷却降温控制；(3)反应后的产物为浆液混合物,将浆液混合物转入压滤器进行压滤过滤去除未反应物,压滤得到的液体进入结晶器进行结晶,得到含有结晶的液体,其中的结晶为七水硫酸镁产品。本发明还公开了一种实施上述连续反应工艺的连续反应设备。本发明使得七水硫酸镁能实现连续化、自动化、安全化的生产,且反应效率高、能耗低、清洁环保。(The invention discloses a continuous reaction process of magnesium sulfate heptahydrate, which comprises the following steps: (1) a solid-liquid mixer with high-speed shearing is used as a reactor, and water and/or mother liquor, 50-98% sulfuric acid and magnesium oxide powder are added into the solid-liquid mixer at the same time; (2) in the reaction process, cooling and temperature reduction control are carried out through temperature control equipment of the reactor; (3) and (3) transferring the slurry mixture into a pressure filter to perform pressure filtration to remove unreacted substances, and feeding the liquid obtained by pressure filtration into a crystallizer to perform crystallization to obtain liquid containing crystals, wherein the crystals are magnesium sulfate heptahydrate products. The invention also discloses continuous reaction equipment for implementing the continuous reaction process. The method can realize continuous, automatic and safe production of the magnesium sulfate heptahydrate, and has the advantages of high reaction efficiency, low energy consumption, cleanness and environmental protection.)

1. A continuous reaction process of magnesium sulfate heptahydrate is characterized by comprising the following steps:

(1) a solid-liquid mixer with high-speed shearing is used as a reactor, and water and/or mother liquor, 50-98% sulfuric acid and magnesium oxide powder are added into the solid-liquid mixer at the same time;

(2) in the reaction process, cooling and temperature reduction control are carried out through temperature control equipment of the reactor;

(3) and (3) transferring the slurry mixture into a pressure filter to perform pressure filtration to remove unreacted substances, and feeding the liquid obtained by pressure filtration into a crystallizer to perform crystallization to obtain liquid containing crystals, wherein the crystals are magnesium sulfate heptahydrate products.

2. The continuous reaction process of magnesium sulfate heptahydrate according to claim 1, wherein the temperature control device of the reactor is a jacket arranged on the outer ring of the reactor, and the temperature of the reaction is controlled to be 70-100 ℃ by introducing a cooling medium.

3. The continuous reaction process of magnesium sulfate heptahydrate according to claim 1, wherein the liquid containing the crystals is centrifuged by a centrifugal device, the obtained crystals are magnesium sulfate heptahydrate products, and mother liquor obtained by centrifugation is recycled to the reactor for continuous reaction.

4. The continuous reaction process of magnesium sulfate heptahydrate according to any one of claims 1 to 3, wherein the adding speed of liquid and powder is controlled by a flow meter and a powder feeder during the reaction process, so as to control the uniformity of the reaction; and water and/or mother liquor, and 50-98% concentration sulfuric acid and magnesia powder are added through different material inlets.

5. A continuous reaction apparatus for magnesium sulfate heptahydrate, which is used for carrying out the continuous reaction process for magnesium sulfate heptahydrate according to any one of claims 1 to 4, comprising: a reactor, a filter press and a crystallizer;

the reactor adopts a solid-liquid mixer with high-speed shearing, the reactor is connected with a pressure filter through a pipeline, and the pressure filter is connected with a crystallizer through a pipeline; the reactor is provided with a temperature control device.

6. The continuous reaction equipment for magnesium sulfate heptahydrate as claimed in claim 5, wherein the temperature control equipment of the reactor is a jacket arranged on the outer ring of the reactor and is used for controlling the temperature reduction of the reaction by introducing a cooling medium.

7. The continuous reaction equipment for magnesium sulfate heptahydrate according to claim 5 or 6, wherein the reactor is provided with liquid feed inlets corresponding to the amount of liquid materials, and a powder feed inlet.

8. The continuous reaction equipment for magnesium sulfate heptahydrate according to claim 7, wherein the liquid feed inlet of the reactor is provided with a flow meter, and the powder feed inlet of the reactor is provided with a powder feeder.

9. The continuous reaction equipment for magnesium sulfate heptahydrate according to claim 5 or 6, wherein the solid-liquid mixer with high-speed shearing adopts a pump type high-speed shearing solid-liquid mixer; or the solid-liquid mixer with high-speed shearing adopts a transverse pipeline type high-speed shearing solid-liquid mixer driven by a motor, and a motor shaft of the motor is arranged along the axial direction of the pipeline.

10. The continuous reaction equipment for magnesium sulfate heptahydrate according to claim 5 or 6, wherein the high-speed shearing solid-liquid mixer is a high-speed shearing solid-liquid mixer with the rotating speed of more than 2000 r/min.

Technical Field

The invention relates to the field of inorganic synthesis, in particular to a continuous reaction process and continuous reaction equipment for magnesium sulfate heptahydrate.

Background

Magnesium sulfate heptahydrate of the formula MgSO₄·7H₂And O is white or colorless needle-shaped or inclined column-shaped crystal. The method is mainly used for manufacturing fertilizers, leathers, printing and dyeing, catalysts, papermaking, plastics, porcelain, pigments, matches, explosives and fireproof materials, can be used for printing and dyeing thin cotton cloth and silk, can be used as a weighting agent of cotton silk and a filler of kapok products, and can be used as epsom salt in medicine.

The existing magnesium sulfate heptahydrate mainly utilizes 50% -98% concentration sulfuric acid and magnesium oxide powder to carry out kettle type reaction, which comprises the following steps: (1) a constant amount of mother liquor or water and magnesium oxide powder are injected into the reaction kettle, and then a constant amount of sulfuric acid is added while stirring for reaction. (2) During the reaction, the speed of adding sulfuric acid is controlled to control the reaction intensity. (3) The end point of the addition of sulfuric acid was determined by measuring the pH at the end of the reaction. The existing magnesium sulfate heptahydrate reaction process has the following defects:

(1) the existing reaction method is a kettle type reaction, continuous reaction cannot be achieved, the problem of uneven heat distribution in a kettle due to the temperature control problem in the reaction process is often solved, and the reaction is aggravated when the temperature is too high, so that kettle spraying or overflow is caused, and dangerousness is brought to the production process. When the temperature is too low, the reaction is insufficient, the magnesium powder is condensed to form a large solid, so that the stirrer is damaged, and the whole reaction is interrupted.

(2) In the reaction process, the phenomenon of concentrated heating is easy to occur, and a large amount of smoke, water vapor and sulfuric acid mist are generated.

(3) The reaction time is too long, 12-24 hours is a complete reaction period, and the energy consumption is large.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a reaction process of magnesium sulfate heptahydrate, which can realize continuous, automatic and safe production, and has the advantages of high reaction efficiency, low energy consumption, cleanness and environmental protection.

In order to solve the technical problems, the invention adopts the following technical scheme:

a continuous reaction process for magnesium sulfate heptahydrate, comprising:

(1) a solid-liquid mixer with high-speed shearing is used as a reactor, and water and/or mother liquor, 50-98% sulfuric acid and magnesium oxide powder are added into the solid-liquid mixer at the same time;

(2) in the reaction process, cooling and temperature reduction control are carried out through temperature control equipment of the reactor;

(3) and (3) transferring the slurry mixture into a pressure filter to perform pressure filtration to remove unreacted substances, and feeding the liquid obtained by pressure filtration into a crystallizer to perform crystallization to obtain liquid containing crystals, wherein the crystals are magnesium sulfate heptahydrate products.

Further, the temperature control equipment of the reactor is a jacket arranged on the outer ring of the reactor, the reaction is cooled and controlled by introducing a cooling medium, and the temperature is controlled to be 70-100 ℃.

Further, the liquid containing the crystals is centrifuged by a centrifugal device, the obtained crystals are magnesium sulfate heptahydrate products, and mother liquor obtained by centrifuging is circulated into the reactor for continuous reaction.

Further, in the reaction process, the adding speed of liquid and powder is controlled by a flowmeter and a powder feeder so as to control the uniformity of the reaction; and water and/or mother liquor, and 50-98% concentration sulfuric acid and magnesia powder are added through different material inlets.

The invention also discloses continuous reaction equipment for magnesium sulfate heptahydrate, which is used for implementing the continuous reaction process for magnesium sulfate heptahydrate, and comprises the following steps: a reactor, a filter press and a crystallizer; the reactor adopts a solid-liquid mixer with high-speed shearing, the reactor is connected with a pressure filter through a pipeline, and the pressure filter is connected with a crystallizer through a pipeline; the reactor is provided with a temperature control device.

Furthermore, the temperature control device of the reactor is a jacket arranged on the outer ring of the reactor and is used for controlling the temperature reduction of the reaction by introducing a cooling medium.

Furthermore, the reactor is provided with liquid feed inlets corresponding to the quantity of the liquid materials, and a powder feed inlet.

Furthermore, a liquid feeding port of the reactor is provided with a flowmeter, and a powder feeding port of the reactor is provided with a powder feeder.

Further, the solid-liquid mixer with high-speed shearing adopts a pump type high-speed shearing solid-liquid mixer; or the solid-liquid mixer with high-speed shearing adopts a transverse pipeline type high-speed shearing solid-liquid mixer driven by a motor, and a motor shaft of the motor is arranged along the axial direction of the pipeline.

Further, the high-speed shearing solid-liquid mixer with the high-speed shearing solid-liquid mixer is a high-speed shearing solid-liquid mixer with the rotating speed of more than 2000 r/min.

By adopting the technical scheme, the invention at least has the following advantages:

(1) the invention uses a solid-liquid mixer with high-speed shearing as a reactor, can simultaneously add magnesia powder, mother liquor, water and sulfuric acid raw material with the concentration of 50-98 percent, controls the adding speed through a flowmeter and a powder feeder so as to control the uniformity of reaction, realizes high-speed dispersion and high-speed mixing of reactants in the solid-liquid mixer under the high-speed shearing force of the mixer, ensures that the reaction is carried out instantly, ensures that the reaction product forms slurry and quickly enters a pipeline, realizes the continuity and canalization of the whole reaction, and has uniform and stable reaction temperature.

(2) The reaction product is a slurry mixture, and is directly subjected to filter pressing and further crystallization, so that the time required for integrally producing a finished product can be shortened.

(3) And (3) crystallizing the magnesium sulfate heptahydrate product, and centrifuging to obtain a mother solution, and circulating the mother solution to a solid-liquid mixer for continuous reaction.

(4) Compared with the existing technology, the whole reaction has high dispersion and continuous reaction, greatly reduces the risk of reaction heat aggregation, does not generate smoke dust due to high dispersion of the reaction, also solves the problems of dust vapor and acid mist caused by the reaction heat effect in the existing technology state, and has great significance in environmental protection.

(5) The invention greatly shortens the reaction time from 12-24 hours in the prior art to the minute level, greatly improves the reaction efficiency and reduces the energy consumption required by material reaction.

Drawings

The foregoing is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and the detailed description.

Fig. 1 is a schematic structural diagram of a magnesium sulfate heptahydrate continuous reaction apparatus in an embodiment of the present invention.

Detailed Description

As shown in figure 1, the continuous reaction device for magnesium sulfate heptahydrate comprises a reactor 1, a pressure filter 2 and a crystallizer 3; the reactor 1 is connected to a pressure filter 2 through a pipeline, and the pressure filter 2 is connected to a crystallizer 3 through a pipeline.

Wherein, the reactor 1 adopts a solid-liquid mixer with high-speed shearing, and a pump type high-speed shearing mixer is preferred in the embodiment; alternatively, a transverse pipeline type high-speed shearing solid-liquid mixer driven by a motor can be adopted, and a motor shaft of the motor is arranged along the axial direction of the pipeline. The high-speed shearing solid-liquid mixer is preferably a high-speed shearing solid-liquid mixer with the rotating speed of more than 2000 r/min. The reactor 1 is provided with three liquid feed inlets respectively corresponding to water, mother liquor and 50-98% sulfuric acid, and a powder feed inlet. The liquid feed inlet of the reactor 1 is provided with a flowmeter, and the powder feed inlet of the reactor 1 is provided with a powder feeder.

In addition, the reactor 1 is also provided with a temperature control device; in this embodiment, the temperature control device is preferably disposed in a jacket of the outer ring of the reactor 1, and the temperature of the reaction is controlled by introducing a cooling medium, such as cooling water, so that accurate and automatic control of the temperature can be achieved. It will be appreciated by those skilled in the art that various other temperature control devices known in the art may be used in addition to the outer jacket.

The continuous reaction process for magnesium sulfate heptahydrate by using the continuous reaction equipment comprises the following steps:

(1) a solid-liquid mixer with high-speed shearing is used as a reactor 1, and water, mother liquor, 50-98% concentration sulfuric acid and magnesium oxide powder are added into the reactor 1 through different feed inlets; the molar ratio of magnesium oxide to sulfuric acid is 1: 1. In the reaction process, the adding speed of the liquid and the powder is controlled by a flowmeter and a powder feeder so as to control the uniformity of the reaction.

(2) In the reaction process, cooling control is carried out by passing cooling water into the outer ring jacket, and the temperature is controlled to be 70-100 ℃;

(3) and transferring the slurry mixture into a pressure filter 2 to perform pressure filtration to remove unreacted substances, and feeding the liquid obtained by pressure filtration into a crystallizer 3 to crystallize to obtain liquid containing crystals, wherein the crystals are magnesium sulfate heptahydrate products.

For the liquid containing the crystals, the liquid can be further subjected to centrifugal post-treatment to obtain magnesium sulfate heptahydrate product, and the mother liquor obtained by centrifugation can be used for circulating to the reactor 1 for continuous reaction.

When the magnesium sulfate heptahydrate product (more than ton grade) is produced in large batch, the continuous reaction equipment and the continuous reaction process are utilized, the reaction time can be controlled within the minute level by adopting the scheme of mutually combining 50 percent, 80 percent and 98 percent of sulfuric acid and controlling the temperature at 70 ℃, 80 ℃, 90 ℃ and 100 ℃, and compared with the prior art, the magnesium sulfate heptahydrate can be continuously produced and automatically controlled, the manpower use (the production risk is also reduced), the energy consumption of the reaction is reduced, and no smoke dust is generated (the product is cleaner and more environment-friendly); the reaction time is shortened, and the production efficiency is improved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the present invention in any way, and it will be apparent to those skilled in the art that the above description of the present invention can be applied to various modifications, equivalent variations or modifications without departing from the spirit and scope of the present invention.