阅读说明：本技术 一种有机硅高沸物的处理工艺 (Treatment process of organic silicon high-boiling residues ) 是由 赵武利 路一帆 洪利 彭路梅 陈弘光 皮俊轲 郑云峰 于 2021-08-26 设计创作，主要内容包括：本发明提供一种有机硅高沸物的处理工艺,包括以下步骤：A)将有机硅高沸物与30～35％的浓盐酸在水解反应器中混合,进行水解反应,产生固体颗粒物和氯化氢气体；B)水解反应器中的上层反应液进入反应液循环罐,用做下次水解反应的水解液；下层的固体颗粒物在水解反应器内进行一级洗涤,固液分离后,液体进入一级洗涤液循环罐,固体进入二级洗涤器进行二级洗涤；二级洗涤后进行固液分离,液体进入二级洗涤液循环罐,固体进入三级洗涤器内进行三级洗涤；三级洗涤后进行固液分离,得到固渣和液体,液体进入三级洗涤液循环罐。本发明中的工艺不仅流程简单,且能实现95％以上的氯化氢气体回收,同时减少低浓度废酸的产生。(The invention provides a treatment process of an organic silicon high-boiling residue, which comprises the following steps: A) mixing the organic silicon high-boiling residues with 30-35% of concentrated hydrochloric acid in a hydrolysis reactor, and carrying out hydrolysis reaction to generate solid particles and hydrogen chloride gas; B) the upper layer reaction liquid in the hydrolysis reactor enters a reaction liquid circulating tank and is used as hydrolysis liquid for the next hydrolysis reaction; carrying out primary washing on the solid particles on the lower layer in the hydrolysis reactor, after solid-liquid separation, enabling the liquid to enter a primary washing liquid circulation tank, and enabling the solid to enter a secondary washer for secondary washing; carrying out solid-liquid separation after the secondary washing, enabling the liquid to enter a secondary washing liquid circulation tank, and enabling the solid to enter a tertiary washer for tertiary washing; and carrying out solid-liquid separation after the third-stage washing to obtain solid slag and liquid, and feeding the liquid into a third-stage washing liquid circulating tank. The process disclosed by the invention is simple in flow, can realize the recovery of over 95% of hydrogen chloride gas, and simultaneously reduces the generation of low-concentration waste acid.)

1. A treatment process of organic silicon high-boiling residues comprises the following steps:

A) mixing the organic silicon high-boiling residues with 30-35% of concentrated hydrochloric acid in a hydrolysis reactor, and carrying out hydrolysis reaction to generate solid particles and hydrogen chloride gas;

B) the upper layer reaction liquid in the hydrolysis reactor enters a reaction liquid circulating tank and is used as hydrolysis liquid for the next hydrolysis reaction;

carrying out primary washing on the solid particles on the lower layer in the hydrolysis reactor, after solid-liquid separation, enabling the liquid to enter a primary washing liquid circulation tank, and enabling the solid to enter a secondary washer for secondary washing;

carrying out solid-liquid separation after the secondary washing, enabling the liquid to enter a secondary washing liquid circulation tank, and enabling the solid to enter a tertiary washer for tertiary washing;

and carrying out solid-liquid separation after the third-stage washing to obtain solid slag and liquid, and feeding the liquid into a third-stage washing liquid circulating tank.

2. The treatment process according to claim 1, wherein the hydrolysis temperature is 20-40 ℃; the hydrolysis time is 1-3 hours.

3. The process according to claim 1, wherein the organosilicon high boilers comprise vinyl high boilers, methyl vinyl high boilers;

the content of chlorine in the organic silicon high-boiling residues is 65-70%.

4. The treatment process according to claim 1, wherein the mass ratio of the organosilicon high-boiling components to 30-35% of concentrated hydrochloric acid is 1: (10-15).

5. The treatment process according to claim 1, wherein the chlorine content in the solid particles obtained after the hydrolysis reaction is 19-23%; the concentration of hydrochloric acid in the reaction liquid circulation tank is 32-37%.

6. The treatment process according to claim 1, wherein the liquid in the reaction liquid circulating tank is mixed with part of the liquid in the first-stage washing liquid circulating tank and then used as the hydrolysate for the next circulation;

the liquid in the first-stage washing liquid circulating tank is mixed with part of liquid in the second-stage washing liquid circulating tank and then is used as the first-stage washing liquid of the next cycle;

the liquid in the secondary washing liquid circulating tank is mixed with part of liquid in the tertiary washing liquid circulating tank and then is used as secondary washing liquid for the next circulation;

and the liquid in the third-stage washing liquid circulating tank is mixed with the supplemented water and then is used as the third-stage washing liquid of the next circulation.

7. The process of claim 1, wherein the first, second, and third washes are performed with dilute hydrochloric acid;

the initial hydrochloric acid concentration of the first-stage washing, the second-stage washing and the third-stage washing is 12-18%, 6-10% and 1-5% respectively.

8. The treatment process according to claim 7, wherein the concentrations of the hydrochloric acid in the first, second and third washing liquid circulation tanks are 15-22%, 9-14% and 3-8%, respectively.

9. The treatment process according to claim 1, wherein the chlorine content in the solid obtained by the primary, secondary and tertiary washing and solid-liquid separation is 10-15%, 5-8% and 1-5%, respectively.

Technical Field

The invention belongs to the technical field of organic silicon environmental protection, and particularly relates to a treatment process of organic silicon high-boiling residues.

Background

Landscape technology

The organosilicon high-boiling residue is a byproduct which is generated in the process of producing organosilicon monomers and has strong corrosiveness and higher danger, and the boiling range is in the range of 80-125 ℃, and the organosilicon high-boiling residue is a mixture of silane substances. These substances are highly corrosive and, after contacting with air, rapidly hydrolyze to produce a large amount of hydrogen chloride gas, which makes handling out difficult, but the by-products also present a safety hazard if stored for a long period of time.

Chinese patent CN111717892A describes a process for preparing concentrated hydrochloric acid by hydrolyzing high-boiling components of organosilicon, which comprises hydrolyzing high-boiling components of chlorosilane with 20-30% hydrochloric acid as solvent, recovering hydrogen chloride gas, and absorbing with water to obtain high-concentration hydrochloric acid solution. Although the method can reduce the danger of high-boiling residues and obtain high-concentration hydrochloric acid, the chlorine content in the waste residue generated by hydrolysate is not particularly described, and the waste residue with high chlorine content has some difficulties in dangerous waste disposal.

Chinese patent CN201310357842 introduces a process of organosilicon high-boiling continuous hydrolysis, low-concentration hydrochloric acid solution generated after hydrolysis is neutralized by alkali liquor, high cost investment is needed, salt-containing wastewater needs to be treated regularly, and hydrogen chloride is not recycled, so that resource waste is caused.

In conclusion, a treatment process for organosilicon high-boiling residues must be found, the recovery rate of hydrogen chloride gas can be improved to the greatest extent, the chlorine content in a target object is reduced, and as little dilute acid or salt-containing wastewater as possible is generated.

Disclosure of Invention

The invention aims to provide a treatment process of an organic silicon high-boiling-point substance with high chlorine content, which can reduce the chlorine content in the high-boiling-point substance, realize the recovery of hydrogen chloride and reduce the generation of low-concentration waste hydrochloric acid.

The invention provides a treatment process of an organic silicon high-boiling residue, which comprises the following steps:

A) mixing the organic silicon high-boiling residues with 30-35% of concentrated hydrochloric acid in a hydrolysis reactor, and carrying out hydrolysis reaction to generate solid particles and hydrogen chloride gas;

B) the upper layer reaction liquid in the hydrolysis reactor enters a reaction liquid circulating tank and is used as hydrolysis liquid for the next hydrolysis reaction;

carrying out primary washing on the solid particles on the lower layer in the hydrolysis reactor, after solid-liquid separation, enabling the liquid to enter a primary washing liquid circulation tank, and enabling the solid to enter a secondary washer for secondary washing;

carrying out solid-liquid separation after the secondary washing, enabling the liquid to enter a secondary washing liquid circulation tank, and enabling the solid to enter a tertiary washer for tertiary washing;

and carrying out solid-liquid separation after the third-stage washing to obtain solid slag and liquid, and feeding the liquid into a third-stage washing liquid circulating tank.

Preferably, the hydrolysis temperature is 20-40 ℃; the hydrolysis time is 1-3 hours.

Preferably, the organosilicon high-boiling components comprise vinyl high-boiling components and methyl vinyl high-boiling components;

the content of chlorine in the organic silicon high-boiling residues is 65-70%. .

Preferably, the mass ratio of the organosilicon high-boiling residues to 30-35% of concentrated hydrochloric acid is 1: (10-15).

Preferably, the chlorine content in the solid particles obtained after the hydrolysis reaction is 19-23%; the concentration of hydrochloric acid in the reaction liquid circulation tank is 32-37%.

Preferably, the liquid in the reaction liquid circulating tank is mixed with part of liquid in the first-stage washing liquid circulating tank and then used as the hydrolysate for the next circulation;

the liquid in the first-stage washing liquid circulating tank is mixed with part of liquid in the second-stage washing liquid circulating tank and then is used as the first-stage washing liquid of the next cycle;

the liquid in the secondary washing liquid circulating tank is mixed with part of liquid in the tertiary washing liquid circulating tank and then is used as secondary washing liquid for the next circulation;

and the liquid in the third-stage washing liquid circulating tank is mixed with the supplemented water and then is used as the third-stage washing liquid of the next circulation.

Preferably, dilute hydrochloric acid is adopted for the first-stage washing, the second-stage washing and the third-stage washing;

the initial hydrochloric acid concentration of the first-stage washing, the second-stage washing and the third-stage washing is 12-18%, 6-10% and 1-5% respectively.

Preferably, the concentrations of hydrochloric acid in the first-stage washing liquid circulating tank, the second-stage washing liquid circulating tank and the third-stage washing liquid circulating tank are respectively 15-22%, 9-14% and 3-8%.

Preferably, the chlorine content in the solid obtained by primary, secondary and tertiary washing and solid-liquid separation is 10-15%, 5-8% and 1-5% respectively.

The invention provides a treatment process of an organic silicon high-boiling residue, which comprises the following steps: A) mixing the organic silicon high-boiling residues with 30-35% of concentrated hydrochloric acid in a hydrolysis reactor, and carrying out hydrolysis reaction to generate solid particles and hydrogen chloride gas; B) the upper layer reaction liquid in the hydrolysis reactor enters a reaction liquid circulating tank and is used as hydrolysis liquid for the next hydrolysis reaction; carrying out primary washing on the solid particles on the lower layer in the hydrolysis reactor, after solid-liquid separation, enabling the liquid to enter a primary washing liquid circulation tank, and enabling the solid to enter a secondary washer for secondary washing; carrying out solid-liquid separation after the secondary washing, enabling the liquid to enter a secondary washing liquid circulation tank, and enabling the solid to enter a tertiary washer for tertiary washing; and carrying out solid-liquid separation after the third-stage washing to obtain solid slag and liquid, and feeding the liquid into a third-stage washing liquid circulating tank. The invention aims at the treatment of organosilicon high-boiling residues with high chlorine content, firstly uses concentrated hydrochloric acid for hydrolysis, recovers hydrogen chloride gas generated by hydrolysis, and then uses low-concentration hydrochloric acid for three-stage washing, wherein the application mode of each stage of washing is to mix a part of next-stage washing liquid with previous-stage washing liquid for reuse as the washing liquid, thereby ensuring that no waste acid is generated in the whole reaction process. The process disclosed by the invention is simple in flow, can realize the recovery of over 95% of hydrogen chloride gas, and simultaneously reduces the generation of low-concentration waste acid.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a flow chart of the process for treating organosilicon high boilers;

the dotted line box in FIG. 1 indicates that the step reaction and the hydrolysis reaction are carried out in the same vessel (hydrolysis reactor).

Detailed Description

The invention provides a treatment process of an organic silicon high-boiling residue, which comprises the following steps:

A) mixing the organic silicon high-boiling residues with 30-35% of concentrated hydrochloric acid in a hydrolysis reactor, and carrying out hydrolysis reaction to generate solid particles and hydrogen chloride gas;

B) the upper layer reaction liquid in the hydrolysis reactor enters a reaction liquid circulating tank and is used as hydrolysis liquid for the next hydrolysis reaction;

carrying out primary washing on the solid particles on the lower layer in the hydrolysis reactor, after solid-liquid separation, enabling the liquid to enter a primary washing liquid circulation tank, and enabling the solid to enter a secondary washer for secondary washing;

carrying out solid-liquid separation after the secondary washing, enabling the liquid to enter a secondary washing liquid circulation tank, and enabling the solid to enter a tertiary washer for tertiary washing;

and carrying out solid-liquid separation after the third-stage washing to obtain solid slag and liquid, and feeding the liquid into a third-stage washing liquid circulating tank.

In the invention, the organic silicon high-boiling-point substance comprises a vinyl high-boiling-point substance, a methyl vinyl high-boiling-point substance and the like, wherein the vinyl high-boiling-point substance is a byproduct generated in the production process of vinyl trichlorosilane, and the chlorine content in the organic silicon high-boiling-point substance is high (65-70%), and the common outward transportation treatment method is difficult. The method comprises the steps of firstly hydrolyzing the organic silicon high-boiling residues in a hydrolysis reactor, wherein the hydrolysis liquid used for hydrolysis is 30-35% of concentrated hydrochloric acid, and after hydrolysis reaction, solid particles and hydrogen chloride gas are generated.

The invention preferably puts concentrated hydrochloric acid as hydrolysate into a hydrolysis reactor, then drops the organic silicon high-boiling residue into the hydrolysate, continuously stirs to ensure that the hydrolysis reaction is complete, and recovers the hydrogen chloride gas generated in the process as a byproduct for use

In the present invention, the mass ratio of the organosilicon high boiling substance to the concentrated hydrochloric acid is preferably 1: (10-15), more preferably 1: (11-14), most preferably 1: (12-13). The temperature of the hydrolysis reaction is preferably 20-40 ℃, more preferably 25-35 ℃, and most preferably 30 ℃; the hydrolysis time is preferably 1 to 3 hours, and more preferably 1 to 2 hours.

The invention adopts high-concentration hydrochloric acid as hydrolysis liquid in hydrolysis to avoid the spherical solid particles generated after hydrolysis, thereby ensuring that the chlorine content in the particles can meet the requirement after the subsequent several stages of water washing. After the concentrated hydrochloric acid with the concentration used in the invention is hydrolyzed, the obtained solid particles are flaky, and in the subsequent three-stage washing process, chloride ions on the surfaces of the flaky solid particles are easier to clean than chloride ions on the surfaces of spherical solid particles.

After the hydrolysis reaction is completed, the upper layer reaction liquid in the hydrolysis reactor enters a reaction liquid circulating tank, and solid particles are left in the hydrolysis reactor. The concentration of hydrochloric acid in the reaction liquid circulation tank after the hydrolysis reaction is 32-37%, and the chlorine content in the solid particles is 19-23%.

In the organic silicon high-boiling-point substance, substances generated after hydrolysis are solid particles, and can not be subjected to oil-water separation like chlorosilane in other prior art after hydrolysis, and the generated oily substance is directly pumped into a next-stage washing system; in the invention, solid particles generated after hydrolysis need to be manually fished out and then are sent into the next-stage washing system. After hydrolysis in a high-concentration hydrochloric acid solution, the chlorine content in the particles is very high, and great safety risk exists in manual slag removal. The invention provides a new form, namely, the hydrolysis reaction and the first-stage washing are carried out in the same reactor, the mixed slurry is kept still in the reactor for solid-liquid separation after hydrolysis, the obtained solution is temporarily stored in a reaction liquid circulating tank, and then the solution returns to a hydrolysis system for the next cycle of hydrolysis reaction; and carrying out primary washing on the solid slag in a hydrolysis reactor.

The slag slurry after the first-stage washing enters a plate-and-frame filter pressing system for solid-liquid separation, after the solid-liquid separation, the liquid enters a first-stage washing liquid circulating tank for temporary storage, and then returns to a first-stage washing system of the next cycle, and the solid enters a second-stage washer for second-stage washing;

carrying out solid-liquid separation after the secondary washing, enabling the liquid to enter a secondary washing liquid circulation tank, and enabling the solid to enter a tertiary washer for tertiary washing;

and carrying out solid-liquid separation after the third-stage washing to obtain solid slag and liquid, and feeding the liquid into a third-stage washing liquid circulating tank.

The raw material for hydrolysis treatment is a mixed substance because the raw material is a high-boiling-point substance generated in the process of producing the vinyltrichlorosilane. Unlike the existing trichlorosilane hydrolysis process, solid particles are generated after hydrolysis, but oil is not generated. The water content of the particles after filtration is measured by experiments to be about 60-70% and a certain amount of hydrogen chloride. When the concentration of the hydrochloric acid solution for washing and the dosage of the whole circulating water supplement are selected, the moisture participating in the hydrolysis reaction and the escaped hydrogen chloride gas are removed, and the amounts of the moisture and the hydrogen chloride carried away by the particles in the hydrolysis and each stage of washing process are also considered. Thereby increasing the difficulty of recycling each grade of hydrochloric acid solution.

Therefore, the invention ensures that no waste acid is generated in the whole hydrolysis and washing process by controlling the concentration of the washing liquid used in the three-stage washing and the recycling mode of the washing liquid in the three-stage washing.

In the invention, the three-stage washing process is carried out at normal temperature and normal pressure, the initial hydrochloric acid concentration of the first-stage washing is 12-18%, preferably 13-16%, such as 12%, 13%, 14%, 15%, 16%, 17%, 18%, preferably a range value taking any value as an upper limit or a lower limit;

the initial hydrochloric acid concentration of the secondary washing is 6-10%, preferably 7-9%, such as 6%, 7%, 8%, 9%, 10%, preferably a range value taking any value of the above as an upper limit or a lower limit;

the initial hydrochloric acid concentration of the three-stage washing is 1-5%, preferably 2-4%, such as 1%, 2%, 3%, 4%, 5%. Preferably a range value having any of the above numerical values as an upper limit or a lower limit;

in the invention, the time of each stage of washing is 0.5-2 hours, and the time of solid-liquid separation is 0.5-2 hours.

The washing liquid is reused in the mode that a part of next-stage washing liquid (after washing) is mixed with the current-stage washing liquid (after washing) and then is reused as the next-circulating current-stage washing liquid. (for example, the second and third washing liquid 100kg, the first washing, second, third washing liquid 80kg, the third washing liquid 20kg and the second washing liquid mixed after being used as the next second washing liquid.)

Specifically, the liquid in the reaction liquid circulation tank is mixed with part of liquid in the first-stage washing liquid circulation tank and then used as the hydrolysis liquid of the next circulation;

the liquid in the first-stage washing liquid circulating tank is mixed with part of liquid in the second-stage washing liquid circulating tank and then is used as the first-stage washing liquid of the next cycle;

the liquid in the secondary washing liquid circulating tank is mixed with part of liquid in the tertiary washing liquid circulating tank and then is used as secondary washing liquid for the next circulation;

and the liquid in the third-stage washing liquid circulating tank is mixed with the supplemented water and then is used as the third-stage washing liquid of the next circulation.

The ratio of the next-stage washing liquid (after washing) is not particularly limited, and the rest of the washing liquid of the current stage after washing can be supplemented to the initial dosage in principle.

In the invention, the concentration of the hydrochloric acid in the primary washing liquid circulating tank is 15-22%, preferably 18-20%, such as 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, preferably a range value with any value of the above values as an upper limit or a lower limit;

the concentration of the hydrochloric acid in the secondary washing liquid circulating tank is 9-14%, such as 9%, 10%, 11%, 12%, 13%, 14%, preferably the range value taking any value as the upper limit or the lower limit;

the concentration of hydrochloric acid in the secondary washing liquid circulating tank is 3-8%, such as 3%, 4%, 5%, 6%, 7%, 8%, preferably the range value taking any value as the upper limit or the lower limit.

The main component of the solid obtained by solid-liquid separation after each stage of washing is solid polysiloxane, wherein the content of chlorine in the solid obtained by solid-liquid separation after the first stage of washing is 10-15%, such as 10%, 11%, 12%, 13%, 14% and 15%, and preferably the range value taking any value as the upper limit or the lower limit;

the chlorine content in the solid obtained by the solid-liquid separation after the secondary washing is 5-8%, such as 5%, 6%, 7% and 8%, and preferably ranges in which any value is an upper limit or a lower limit;

the chlorine content in the solid obtained by solid-liquid separation after the third-stage washing is 1-5%, such as 1%, 2%, 3%, 4%, 5%, preferably any of the above values is used as an upper limit or a lower limit.

FIG. 1 is a flow chart of the process for treating organosilicon high boilers, which is illustrated in FIG. 1:

the hydrolysis reaction described in the invention comprises a hydrolysis reactor for reaction and a reaction liquid circulating tank for temporary storage of solution. The concentrated hydrochloric acid solution as the hydrolysate is injected into a hydrolysis reactor in advance, a certain amount of vinyl high-boiling is dripped into the hydrolysate, solid particles and hydrogen chloride gas are gradually generated, the hydrogen chloride gas is subjected to a foam remover to remove volatile siloxane and water in the hydrogen chloride gas, and the hydrogen chloride gas is removed from the system to be used as a byproduct. The hydrolysis reaction is preferably carried out at normal pressure and at the temperature of 20-40 ℃; the initial concentration of the concentrated hydrochloric acid is 30-35%, the concentration of the hydrochloric acid in the reaction liquid circulation tank after hydrolysis reaction is 32-37%, and the chlorine content of the solid residue is 19-23%.

After the hydrolysis reaction is finished, the solid-liquid mixed slag slurry is placed in a reactor for settlement, the upper layer reaction liquid enters a reaction liquid circulating tank through a blue filter, is mixed with part of solution in a first-stage circulating tank and then is used as the next circulating hydrolysis liquid, and the lower layer solid slag is subjected to first-stage washing in the reactor. And (3) carrying out plate-and-frame filter pressing on the residue slurry, feeding the filtrate into a first-stage washing liquid circulating tank, mixing the filtrate with part of solution in a second-stage circulating tank, and then using the mixture as a next circulating primary washing liquid. The second and third washing processes are the same as the first and second washing processes, and pure soft water is added into the system in the third washing process to maintain the stability of the whole system. The washing process is carried out at normal temperature and normal pressure; the initial hydrochloric acid concentration of the first, second and third washing systems is preferably 12-18%, 6-10% and 1-5%, the hydrochloric acid concentration in the first, second and third washing liquid circulating tanks after washing is 15-22%, 9-14% and 3-8%, and the chlorine content of the solid polysiloxane is 10-15%, 5-8% and 1-5%.

The invention provides a treatment process of an organic silicon high-boiling residue, which comprises the following steps: A) mixing the organic silicon high-boiling residues with 30-35% of concentrated hydrochloric acid in a hydrolysis reactor, and carrying out hydrolysis reaction to generate solid particles and hydrogen chloride gas; B) the upper layer reaction liquid in the hydrolysis reactor enters a reaction liquid circulating tank and is used as hydrolysis liquid for the next hydrolysis reaction; carrying out primary washing on the solid particles on the lower layer in the hydrolysis reactor, after solid-liquid separation, enabling the liquid to enter a primary washing liquid circulation tank, and enabling the solid to enter a secondary washer for secondary washing; carrying out solid-liquid separation after the secondary washing, enabling the liquid to enter a secondary washing liquid circulation tank, and enabling the solid to enter a tertiary washer for tertiary washing; and carrying out solid-liquid separation after the third-stage washing to obtain solid slag and liquid, and feeding the liquid into a third-stage washing liquid circulating tank. The invention aims at the treatment of organosilicon high-boiling residues with high chlorine content, firstly uses concentrated hydrochloric acid for hydrolysis, recovers hydrogen chloride gas generated by hydrolysis, and then uses low-concentration hydrochloric acid for three-stage washing, wherein the application mode of each stage of washing is to mix a part of next-stage washing liquid with previous-stage washing liquid for reuse as the washing liquid, thereby ensuring that no waste acid is generated in the whole reaction process. The process disclosed by the invention is simple in flow, can realize the recovery of over 95% of hydrogen chloride gas, and simultaneously reduces the generation of low-concentration waste acid.

In order to further illustrate the present invention, the following examples are given to describe the process for treating a high boiling silicone compound in detail, but should not be construed as limiting the scope of the present invention.

The following examples employ a hydrolysis process and a three-stage washing process, and the reaction charges are metered as a batch per batch for a batch reaction.

Example 1

The feeding ratio of the vinyl high-boiling residues to the hydrolysate is 1: 12; the initial concentration of the hydrolysate is 30-33%; the hydrolysis temperature is 20-30 ℃; the initial concentration of the washing liquid is 15-18%, 6-8% and 1-3%, and the washing temperature is 20-30 ℃. The recovery rate of the hydrogen chloride in the whole process is 95 percent; the chlorine content of the final solid slag was 2.7%.

Example 2

The feeding ratio of the vinyl high-boiling residues to the hydrolysate is 1: 12; the initial concentration of the hydrolysate is 30-33%; the hydrolysis temperature is 30-40 ℃; the initial concentration of the washing liquid is 15-18%, 6-8% and 1-3%, and the washing temperature is 20-30 ℃. The recovery rate of the hydrogen chloride in the whole process is 97 percent; the chlorine content of the final solid slag was 1.89%.

Example 3

The feeding ratio of the vinyl high-boiling residues to the hydrolysate is 1: 12; the initial concentration of the hydrolysate is 33 to 35 percent; the hydrolysis temperature is 30-40 ℃; the initial concentration of the washing liquid is 15-18%, 6-8% and 1-3%, and the washing temperature is 20-30 ℃. The recovery rate of the hydrogen chloride in the whole process is 99 percent; the chlorine content of the final solid slag was 1.13%.

Comparative example 1

The feeding ratio of the vinyl high-boiling residues to the hydrolysate is 1: 12; the initial concentration of the hydrolysate is 20-30%; the hydrolysis temperature is 30-40 ℃; a two-stage water washing process is adopted, each stage of water washing is carried out by pure water, and the washing temperature is 20-30 ℃. The recovery rate of hydrogen chloride in the hydrolysis process is 48 percent; the chlorine content of the final solid slag was 3.48%.

Comparative example 2

The feeding ratio of the vinyl high-boiling residues to the hydrolysate is 1: 6; the initial concentration of the hydrolysate is 30-35%; the hydrolysis temperature is 30-40 ℃; a two-stage water washing process is adopted, each stage of water washing is carried out by pure water, and the washing temperature is 20-30 ℃. The recovery rate of hydrogen chloride in the hydrolysis process is 53 percent; the chlorine content of the final solid slag was 2.57%.

TABLE 1 Process effects of examples of the invention and comparative examples

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.