Process and system for reducing acid value of hydrolysate in separation and washing process of dimethyl dichlorosilane hydrolysate

Abstract

The invention relates to a process and a system for reducing the acid value of hydrolysate in the separation and washing process of dimethyl dichlorosilane hydrolysate. Comprising three stages of coalescers, dimethyl dichlorosilane acidic hydrolysate enters the system from the first stage of coalescer, process water enters the system from the third stage of coalescer, the acidic hydrolysate and diluted hydrochloric acid or process water are mixed in each stage of coalescer, oil-water two-phase separation is completed through multiple times of washing and coalescence, and meanwhile the acid value of the hydrolysate is reduced; each stage of coalescer comprises two static mixers connected in series, a group of prefilters and a large coalescer, the coalescer is Z-shaped, and four stages of filter elements are arranged in each stage of coalescer. Through repeated tests, a modified polyvinylidene fluoride filter element of Pall Company is finally selected, and after continuous three-stage coalescer treatment, the acid value of dimethyldichlorosilane hydrolysate can be reduced to 10 PPM or below.

Description

Technical Field

[0001] The present invention relates to a process and system device for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing. The agglomeration device greatly reduces the chloride ion content in the hydrolyzate while reducing the amount of water replenishment, belonging to the field of organic silicon technology. Background Art

[0002] At present, the neutral hydrolyzates produced by mainstream domestic silicone monomer manufacturers mostly adopt a weak base neutralization-water washing and stratification process. This process has a long residence time for the hydrolyzate and involves more equipment for reaction, storage and separation. The obtained neutral hydrolyzate has a high chloride ion content and high viscosity. In addition, soda ash needs to be introduced during the purification process to neutralize the hydrolyzate, supplemented by a large amount of process water for boiling and washing purification. During this period, the washing kettle consumes steam and produces a large amount of additional alkaline wastewater that needs to be treated, which is not conducive to building a resource-saving and environmentally friendly society. Summary of the invention

[0003] In view of the above technical problems, the present invention provides a process and system device for reducing the acid value of dimethyldichlorosilane hydrolyzate during the separation and washing process of dimethyldichlorosilane hydrolyzate. The device includes a continuous multi-stage coalescer device, preferably a three-stage coalescer device. The dimethyldichlorosilane acidic hydrolyzate enters the system from the first-stage coalescer, and the process water enters the system from the third-stage coalescer. In each stage of the coalescer, the acidic hydrolyzate is mixed with dilute hydrochloric acid or process water, and the oil-water two-phase separation is completed after multiple washing and coalescing, and the acid value of the hydrolyzate is reduced at the same time; each stage of the coalescer includes: two series static mixers, a group of pre-filters, and a large coalescer. The coalescer is in a "Z" shape, and each stage of the coalescer contains 4 levels of filter elements. Through repeated experiments, the modified polyvinylidene fluoride filter element of Pall Corporation was finally selected. After continuous three-stage coalescer treatment, the acid value of dimethyldichlorosilane hydrolyzate can be reduced to below 10 PPM. This agglomeration device replaces the traditional alkaline washing + water washing method of acid hydrolyzate, which reduces the acid value of the hydrolyzate and significantly reduces the generation of wastewater, thus avoiding the disadvantages of high energy consumption and high pollution of the traditional multi-stage alkaline washing-water washing process.

[0004] The device comprises at least one stage aggregator device, wherein the aggregator device comprises a hydrolyzate pipeline connected to a static mixer, the static mixer connected to a pre-filter, the pre-filter connected to a coalescer, and the coalescer connected to a finished hydrolyzate product area.

[0005] The static mixer is two stages of identical static mixers connected in series. The static mixer can fully mix the dimethylsiloxane acid hydrolyzate with water, which is beneficial to reduce the chloride ion content in the hydrolyzate and reduce the acid value of the hydrolyzate.

[0006] The pre-filter is a two-stage pre-filter connected in series. The pre-filter removes impurities in the oil-water mixture, prevents impurities from clogging the coalescer filter element, and protects the special coalescer filter element from being blocked and damaged by impurities. On the other hand, the pre-filter also reduces the emulsification of the mixture.

[0007] In the coalescer, the first horizontal unit containing a filter element is connected to the lower part of the second vertical unit containing a filter element, the upper part of the second vertical unit containing a filter element is connected to the third horizontal unit containing a filter element, and the third horizontal unit containing a filter element is connected to the lower part of the fourth vertical unit containing a filter element.

[0008] The filter element in the first transverse unit containing a filter element is arranged in the middle of the first transverse unit containing a filter element, and cavities are formed at both ends of the first transverse unit containing a filter element. The front cavity is a buffer zone for the hydrolysis mixture filtered by the pre-filter to enter, so that the hydrolysis mixture is coalesced and separated through the first filter element and enters the cavity at the end.

[0009] The filter element in the second vertical unit containing the filter element is arranged in the middle of the second vertical unit containing the filter element, and cavities are formed at the upper and lower ends of the second vertical unit containing the filter element. In some embodiments, it can be seen that the middle part refers to the inside, and the arrangement position of the filter element realizes that there are cavities at both ends, and the volume of the cavities can be the same or different.

[0010] The first transverse unit containing the filter element is connected to the second vertical unit containing the filter element at the lower end cavity position.

[0011] In some embodiments, it can be understood that after being gathered and filtered by the first horizontal unit containing the filter element, the material enters the lower end cavity of the second vertical unit containing the filter element from the end cavity of the first horizontal unit containing the filter element, and after the hydrolyzed mixed material gradually gathers, it is filtered upward from the filter element in the second vertical unit containing the filter element, and the filtered material enters the upper cavity of the second vertical unit containing the filter element.

[0012] In some embodiments, it can be understood that the length of the second vertical unit containing the filter element is much greater than the length of the first horizontal unit containing the filter element, such as 10-50 times the length. The length of the lower cavity of the second vertical unit containing the filter element is much greater than the length of the first horizontal unit containing the filter element, such as 5-20 times, to achieve a sufficiently long buffer time and buffer zone, so that the hydrolyzed mixed material that is aggregated and filtered by the length of the first horizontal unit containing the filter element is aggregated and settled in the lower cavity, and oil-water separation is achieved, the water phase sinks, the oil phase floats, and the oil phase is filtered through the filter element under the action of the water phase.

[0013] In some embodiments, it can be understood that the length of the upper cavity of the second vertical unit containing the filter element is much longer than the length of the third horizontal unit containing the filter element, such as 5-20 times, to achieve a sufficiently long buffer time and buffer zone, so that the oil phase filtered in the second vertical unit containing the filter element overflows and slowly enters the third horizontal unit containing the filter element.

[0014] The filter element in the third horizontal unit containing a filter element is arranged in the middle of the third horizontal unit containing a filter element, and cavities are formed at both ends of the third horizontal unit containing a filter element; wherein, one end cavity is connected to the upper end cavity position of the second vertical unit containing a filter element, and the other end cavity is connected to the fourth vertical unit containing a filter element.

[0015] In some embodiments, it can be understood that the cavity at one end receives the hydrolysis mixture overflowing from the upper cavity of the second vertical unit containing the filter element, and is filtered through the filter element before entering the cavity at the end.

[0016] The first transverse unit containing a filter element and the third transverse unit containing a filter element may have the same structure size and the same filter element position.

[0017] The filter element in the fourth vertical unit containing the filter element is arranged at the upper part of the fourth vertical unit containing the filter element, and a cavity is formed at the lower part of the fourth vertical unit containing the filter element, and the cavity at the other end of the third horizontal unit containing the filter element is connected to the lower cavity position of the fourth vertical unit containing the filter element.

[0018] In some embodiments, it can be understood that the hydrolysis mixture from the third horizontal unit containing the filter element enters into the lower cavity of the fourth vertical unit containing the filter element, and the volume of the lower cavity is larger than the cavity of the third horizontal unit containing the filter element, such as 1-10 times, and the lower cavity serves as a buffer zone to achieve re-separation of oil and water in the hydrolysis mixture.

[0019] The filter element is selected from a polyolefin special filter element.

[0020] In the technical solution of the present invention, the coalescer innovatively adopts a "Z"-shaped structure. A single coalescer can accommodate 4 special filter elements, and the equipment volume is efficiently utilized. The coalescer of this device adopts a "Z"-shaped structure, which can accommodate four-stage filter elements, making the most of the equipment space, reducing the number of equipment and saving equipment space. The "Z"-shaped structure has two upper and lower sedimentation areas, which is convenient for controlling the gravity sedimentation separation of oil and water.

[0021] The bottom of the cavity of the second vertical unit containing the filter element is connected to the hydrolyzate pipeline via a pipeline. The pipeline is provided with a process water feed pipe and / or a return acid feed pipe to form a device for circulating separation and removing chloride ions.

[0022] When the device for reducing the acid value in the process of separating and washing the hydrolyzate of dimethyldichlorosilane contains a multi-stage aggregator device, each stage of the aggregator device is connected in series, and the structure of each stage of the aggregator device is basically the same as understood by those skilled in the art. In each stage of the aggregator device, the bottom of the second vertical unit containing the filter element is connected to the discharge pipe of the hydrolyzate of the previous stage through a pipeline; at the same time, the bottom of the second vertical unit containing the filter element in the last stage of the aggregator device is connected to the discharge pipe of the hydrolyzate of the previous stage through a pipeline, and a process water feed pipe and / or a return acid feed pipe are provided, forming a device for circulating separation and removing chloride ions.

[0023] Take the multi-stage aggregator device as an example in which three-stage aggregator devices are connected in series; the bottom of the second vertical unit containing a filter element in the third-stage aggregator device is connected to the second-stage hydrolyzate feed pipeline via a pipeline; the bottom of the second vertical unit containing a filter element in the second-stage aggregator device is connected to the first-stage hydrolyzate feed pipeline via a pipeline.

[0024] The interface meter is used to control the liquid level at the bottom of the coalescer to ensure that the acid liquid interface at the bottom is low enough and will not be carried along with the hydrolyzate to the lower coalescer, thus improving the coalescing efficiency, making the process control stable and the product quality uniform. The pipeline sight glasses between each process and the sight glasses of the equipment body can be used to directly observe the form of the hydrolysis products of dimethyldichlorosilane in the system, and timely adjust the parameters such as the oil-water interface and the acid supplement flow rate.

[0025] At the same time, the bottom of the second vertical unit containing the filter element in the third-stage aggregator device is connected to the second-stage hydrolyzate discharge pipe through a pipe, and a process water feed pipe and / or a return acid feed pipe are arranged on the pipe, forming a circulating separation device for removing chloride ions.

[0026] The acidic hydrolyzate of the first transverse unit containing the filter element and the third transverse unit containing the filter element enters from the inside of the filter element and exits from the outside; The acidic hydrolyzate of the second vertical unit containing the filter element and the fourth vertical unit containing the filter element enters from the outside of the filter element and exits from the inside.

[0027] The front and rear ends of the first transverse unit containing the filter element and the third transverse unit containing the filter element are both provided with differential pressure transmitters, and differential pressure transmitters are also provided before and after the pre-filter, so that intuitive judgment can be made and equipment can be switched and filter bags can be replaced at any time, which provides guarantee for the stable operation of the whole oil-water separation device.

[0028] In view of the above device, the present invention also provides a method for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of hydrolyzate, using coalescence liquid-liquid separation technology, the hydrolyzate of the device is washed backward step by step by process water, and the settled water phase washes the hydrolyzate forward step by step, and the process carried out by the device, in the process of separation and purification in a device containing only one primary aggregator, includes the following steps: The dimethyldichlorosiloxane hydrolyzate and the water phase enter the static mixer, and after being fully mixed, enter the static mixer, enter the pre-filter for filtration after mixing, and enter the coalescer after filtration. First, the hydrolyzate passes through the first horizontal unit containing the filter element for washing and coalescing, and then the hydrolyzate passes through the second vertical unit containing the filter element upward for repeated coalescing and separation. The separated water phase gathers at the lower end cavity of the first horizontal unit containing the filter element and the second vertical unit containing the filter element, and is transported to the previous coalescer for washing through a delivery pump; the hydrolyzate separated by the second filter element continues to enter the third and fourth filter elements for coalescing and separation, and the separated water phase gathers at the lower end cavity of the third horizontal unit containing the filter element and the fourth vertical unit containing the filter element. The hydrolyzate separated by the fourth filter element flows out of the equipment from the top outlet of the coalescer to obtain purified dimethyldichlorosilane hydrolyzate.

[0029] The acid value of the dimethyldichlorosilane acid hydrolyzate before entering the coalescer is about 0.15~0.5%.

[0030] When the agglomerator device is a multi-stage agglomerator device connected in series, the purified dimethyldichlorosilane hydrolyzate is mixed with the water phase again (the water phase here includes return acid, process water, and circulating dilute acid) and then enters the next-stage agglomerator device, specifically enters the static mixer in the next-stage agglomerator device, and is agglomerated and separated again to obtain purified dimethyldichlorosilane hydrolyzate again. The purified dimethyldichlorosilane hydrolyzate is mixed with the water phase and enters the agglomeration and separation process, thereby realizing the agglomeration liquid-liquid separation technology.

[0031] The coalescer device is a three-stage coalescer device connected in series, and process water is pumped into the inlet of the third-stage coalescer device. After a certain liquid level is reached at the bottom of the connection between the first and second filter elements of the third-stage coalescer, the third-stage circulation pump is started to replenish water to the second-stage coalescer. After a certain liquid level is reached at the bottom of the connection between the first and second filter elements of the second-stage coalescer, the second-stage circulation pump is started to replenish water to the first-stage coalescer. After a certain liquid level is reached at the bottom of the connection between the first and second filter elements of the first-stage coalescer, the first-stage circulation pump is started to replenish water to the front-end system to react with dimethyl. The dimethyldichlorosilane acid hydrolyzate produced by the reaction is filtered through a pre-filter and enters the coalescer for multiple oil-water separations. The hydrolyzate coming out of the coalescer then enters the secondary and tertiary coalescer devices in turn for treatment to obtain purified dimethyldichlorosilane hydrolyzate.

[0032] The volume ratio of process water feed to dimethylformamide in the third-stage coalescer device is 0.2~0.3:1.

[0033] The pressure difference of the pre-filter is less than 50Kpa, and the pressure difference of the first and third filter elements is less than 100Kpa.

[0034] After separation and washing by the method, the acid value of the hydrolyzate is lower than 10 ppm, more preferably lower than 5 ppm, and further preferably lower than 1 ppm.

[0035] In the technical solution of the present invention, firstly, an interface meter is used to control the liquid level at the bottom of the coalescer to ensure that the acid liquid interface at the bottom is low enough and will not be entrained to the lower-level coalescer with the hydrolyzate, thereby improving the coalescing efficiency, stabilizing the process control and uniforming the product quality.

[0036] By calculating the interface meter height and the five-ring water replenishment flow that match the current feed flow, the residence time of the hydrolyzate can be controlled to make the product quality more stable. Secondly, pay attention to the pressure difference before and after each filter and the coalescer filter element, switch the filter and replace the filter bag in time to prevent impurities from being carried into the equipment and causing filter element blockage and damage; thirdly, observe the equipment and pipeline sight glasses, judge its current state by the color and shape of the current hydrolyzate, and provide timely feedback to adjust the reaction interface, water replenishment and other parameters.

[0037] The test results show that the acid value can be reduced to 70% of the raw liquid after treatment in a three-stage coalescer, 90-98% after treatment in a four-stage coalescer, and 98-99.99% after treatment in a five-stage coalescer. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the structure of the first-stage aggregator device, including hydrolyzate pipeline 1, static mixer 2, pre-filter 3, coalescer 4, first horizontal unit 4-1 containing filter element, second vertical unit 4-2 containing filter element, third horizontal unit 4-3 containing filter element, third horizontal unit 4-3 containing filter element, fourth vertical unit 4-4 containing filter element, 5. Liquid level meter, 6. Pressure difference meter, a is process water, b is acidic hydrolyzate, c is finished hydrolyzate, d is dilute acid (or called acid discharge). The shaded part is the installation position of the filter element.

[0039] Figure 2 Schematic diagram of the structure of the three-stage concentrator device. DETAILED DESCRIPTION

[0040] Example 1 A device for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing, the device comprises a primary aggregator device, such as Figure 1 As shown, the aggregator device includes a hydrolyzate pipeline 1 connected to a static mixer 2, the static mixer 2 is connected to a pre-filter 3, the pre-filter 3 is connected to a coalescer 4, and the coalescer 4 is connected to a clean hydrolyzate product area.

[0041] In the coalescer 4, the first horizontal unit 4-1 containing a filter element is connected to the lower part of the second vertical unit 4-2 containing a filter element, the upper part of the second vertical unit 4-2 containing a filter element is connected to the third horizontal unit 4-3 containing a filter element, and the third horizontal unit 4-3 containing a filter element is connected to the lower part of the fourth vertical unit 4-4 containing a filter element.

[0042] The filter element in the first transverse unit 4 - 1 containing a filter element is arranged in the middle of the first transverse unit 4 - 1 containing a filter element, and cavities are formed at both ends of the first transverse unit 4 - 1 containing a filter element.

[0043] The filter element in the second vertical unit 4-2 containing a filter element is arranged in the middle of the second vertical unit 4-2 containing a filter element, and cavities are formed at the upper and lower ends of the second vertical unit 4-2 containing a filter element; The first filter-containing transverse unit 4-1 is connected to the second filter-containing vertical unit 4-2 at the lower end cavity position; the second filter-containing vertical unit 4-2 is longer than the first filter-containing transverse unit 4-1.

[0044] The filter element in the third horizontal unit 4-3 containing a filter element is arranged in the middle of the third horizontal unit 4-3 containing a filter element, and cavities are formed at both ends of the third horizontal unit 4-3 containing a filter element; wherein, one end cavity is connected to the upper end cavity position of the second vertical unit 4-2 containing a filter element, and the other end cavity is connected to the fourth vertical unit 4-4 containing a filter element.

[0045] The filter element in the fourth vertical unit 4-4 containing a filter element is arranged at the upper part of the fourth vertical unit 4-4 containing a filter element, and a cavity is formed at the lower part of the fourth vertical unit 4-4 containing a filter element, and the cavity at the other end of the third horizontal unit 4-3 containing a filter element is connected to the lower cavity position of the fourth vertical unit 4-4 containing a filter element.

[0046] The filter element is selected from the modified polyvinylidene fluoride filter element of Pall Corporation.

[0047] The bottom of the second vertical unit 4-2 containing a filter element is connected to the hydrolyzate pipeline 1 via a pipeline; The pipeline is provided with a process water feed pipe and / or a return acid feed pipe to form a device for circulating, separating and removing chloride ions.

[0048] The front and rear ends of the first horizontal unit 4-1 containing a filter element, the second vertical unit 4-2 containing a filter element, the third horizontal unit 4-3 containing a filter element, and the fourth vertical unit 4-4 containing a filter element are all provided with differential pressure transmitters.

[0049] Example 2 A device for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing, the device comprises a three-stage aggregator device, such as Figure 2As shown, the aggregator device includes a hydrolyzate pipeline 1 connected to a static mixer 2, the static mixer 2 is connected to a pre-filter 3, the pre-filter 3 is connected to a coalescer 4, and the coalescer 4 is connected to a clean hydrolyzate product area.

[0050] In the coalescer 4, the first horizontal unit 4-1 containing a filter element is connected to the lower part of the second vertical unit 4-2 containing a filter element, the upper part of the second vertical unit 4-2 containing a filter element is connected to the third horizontal unit 4-3 containing a filter element, and the third horizontal unit 4-3 containing a filter element is connected to the lower part of the fourth vertical unit 4-4 containing a filter element.

[0051] The filter element in the first transverse unit 4 - 1 containing a filter element is arranged in the middle of the first transverse unit 4 - 1 containing a filter element, and cavities are formed at both ends of the first transverse unit 4 - 1 containing a filter element.

[0052] The filter element in the second vertical unit 4-2 containing a filter element is arranged in the middle of the second vertical unit 4-2 containing a filter element, and cavities are formed at the upper and lower ends of the second vertical unit 4-2 containing a filter element; The first filter-containing transverse unit 4-1 is connected to the second filter-containing vertical unit 4-2 at the lower end cavity position; the second filter-containing vertical unit 4-2 is longer than the first filter-containing transverse unit 4-1.

[0053] The filter element in the third horizontal unit 4-3 containing a filter element is arranged in the middle of the third horizontal unit 4-3 containing a filter element, and cavities are formed at both ends of the third horizontal unit 4-3 containing a filter element; wherein, one end cavity is connected to the upper end cavity position of the second vertical unit 4-2 containing a filter element, and the other end cavity is connected to the fourth vertical unit 4-4 containing a filter element.

[0054] The filter element in the fourth vertical unit 4-4 containing a filter element is arranged at the upper part of the fourth vertical unit 4-4 containing a filter element, and a cavity is formed at the lower part of the fourth vertical unit 4-4 containing a filter element, and the cavity at the other end of the third horizontal unit 4-3 containing a filter element is connected to the lower cavity position of the fourth vertical unit 4-4 containing a filter element.

[0055] The filter element is made of modified PVDF.

[0056] The above is the overall structure of the first-stage aggregator device, wherein the first-stage aggregator device is connected in series with the second-stage aggregator device, and the second-stage aggregator device is connected in series with the third-stage aggregator device, wherein the first-stage aggregator device, the second-stage aggregator device, and the third-stage aggregator device contain the same structural components.

[0057] The fourth vertical unit containing the filter element in the first-stage aggregator device is connected to the static mixer in the second-stage aggregator device to form a connecting piece; the fourth vertical unit containing the filter element in the second-stage aggregator device is connected to the static mixer in the third-stage aggregator device to form a connecting piece, and the top of the fourth vertical unit containing the filter element in the third-stage aggregator device is processed to obtain clean hydrolyzate; thereby forming a series connection.

[0058] The second vertical unit containing the filter element of the three-stage aggregator device is connected to the static mixer of the three-stage aggregator device through a pipeline to form a return material circulation; the second vertical unit containing the filter element of the two-stage aggregator device is connected to the static mixer of the two-stage aggregator device through a pipeline to form a return material circulation; the second vertical unit containing the filter element of the one-stage aggregator device is connected to the static mixer of the one-stage aggregator device through a pipeline to form a return material circulation.

[0059] It is meaningless for a person skilled in the art to know that a circulation pump is connected to the pipeline.

[0060] Example 3 A method for reducing the acid value in the separation and washing process of dimethyldichlorosilane hydrolyzate, the device of Example 2 performs the following process: After pumping process water from the three-stage coalescer device until the equipment is full, start the three-stage circulation pump to circulate the water, and start returning water to the two-stage coalescer device at the same time. When the two-stage coalescer device is full, return water to the first-stage coalescer device. After the first-stage coalescer device is full, pump in the acidic dimethyldichlorosilane hydrolyzate, mix it with the water phase of the second-stage return material at a volume ratio of 3:1 and enter the two-stage static mixer in series for full mixing and extraction. After extraction, filter it through a pre-filter and enter the coalescer for multiple oil-water separations. The hydrolyzate coming out of the coalescer then enters the two-stage coalescer device and the three-stage coalescer device for treatment in turn. When it reaches the static mixer inlet of the three-stage coalescer device, it is mixed with process water from outside the boundary and its own circulating acid to separate the oil and water in the coalescer, and the chloride ion content in the hydrolyzate coming out is greatly reduced.

[0061] In the above-mentioned first-stage coalescer device, second-stage coalescer device, and third-stage coalescer device, the hydrolyzate discharged from the premixer is first separated from oil and water by the first horizontal unit containing a filter element, and the acid deposited at the bottom is pumped to the previous process. The hydrolyzate passes upward through the second vertical unit containing a filter element to repeat the oleic acid separation process. The hydrolyzate after passing through the vertical filter element reaches the top of the coalescer, and is coalesced and separated from oil and water by the third horizontal unit containing a filter element at the top and the fourth vertical unit containing a filter element at the top. The mixture is coalesced and separated by four filter elements and flows out of the coalescer outlet to obtain purified dimethyldichlorosilane hydrolyzate. Each special filter element of the coalescer is provided with a front and rear differential pressure transmitter, and a pressure gauge is also provided before and after the prefilter.

[0062] After separation and washing by the method, the chloride ion content after treatment by the first-stage coalescer device is 500-1000PPM; the chloride ion content after treatment by the second-stage coalescer device is 50-100PPM; and the chloride ion content after treatment by the third-stage coalescer device is 5ppm.

Claims

1. A system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of the hydrolyzate, characterized in that: The device comprises at least one stage agglomerator device, wherein the agglomerator device comprises a hydrolysate feed pipeline (1) connected to a static mixer (2), the static mixer (2) connected to a pre-filter (3), the pre-filter (3) connected to a coalescer (4), and the coalescer (4) connected to a finished hydrolysate product zone.

2. The system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 1, characterized in that: In the coalescer (4), the first transverse unit (4-1) containing a filter element is connected to the lower part of the second vertical unit (4-2) containing a filter element, the upper part of the second vertical unit (4-2) containing a filter element is connected to the third transverse unit (4-3) containing a filter element, and the third transverse unit (4-3) containing a filter element is connected to the lower part of the fourth vertical unit (4-4) containing a filter element.

3. The system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 2, characterized in that: The filter element in the first transverse unit (4-1) containing a filter element is arranged in the middle of the first transverse unit (4-1) containing a filter element, and cavities are formed at both ends of the first transverse unit (4-1) containing a filter element.

4. The system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 3, characterized in that: The filter element in the second vertical unit (4-2) containing the filter element is arranged in the middle of the second vertical unit (4-2) containing the filter element, and cavities are formed at the upper and lower ends of the second vertical unit (4-2) containing the filter element; the cavity at one end of the first horizontal unit (4-1) containing the filter element is connected to the cavity position at the lower end of the second vertical unit (4-2) containing the filter element.

5. The system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 4, characterized in that: The filter element in the third filter-element-containing transverse unit (4-3) is arranged in the middle of the third filter-element-containing transverse unit (4-3), and cavities are formed at both ends of the third filter-element-containing transverse unit (4-3); wherein the cavity at one end is connected to the upper cavity position of the second filter-element-containing vertical unit (4-2), and the cavity at the other end is connected to the fourth filter-element-containing vertical unit (4-4).

6. The system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 5, characterized in that: The filter element in the fourth vertical unit (4-4) containing a filter element is arranged at the upper part of the fourth vertical unit (4-4) containing a filter element, and a cavity is formed at the lower part of the fourth vertical unit (4-4) containing a filter element, and the cavity at the other end of the third horizontal unit (4-3) containing a filter element is connected to the lower cavity position of the fourth vertical unit (4-4) containing a filter element.

7. The system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 1, characterized in that: The bottom of the second vertical unit (4-2) containing a filter element is connected to the hydrolyzate feed pipeline (1) via a pipeline, forming a circulating washing device for reducing the acid value of the hydrolyzate.

8. The system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 1, characterized in that: When the device is a multi-stage aggregator device, each stage of the aggregator device is connected in series, and in each stage of the aggregator device, the top of the fourth vertical unit containing a filter element is connected to the port hydrolyzate feed pipeline of the first horizontal unit containing a filter element of the next stage of the aggregator through a pipeline for conveying acidic hydrolyzate; The bottom of the second vertical unit containing the filter element is connected to the hydrolyzate discharge pipe of the previous stage coalescer through a pipeline to transport dilute hydrochloric acid; The bottom of the second vertical unit containing the filter element in the last-stage aggregator device is connected to the discharge pipe of the hydrolyzate of the previous stage through a pipe, and a process water feed pipe is provided on the pipe, so as to form a circulating washing device to reduce the acid value of the hydrolyzate; The multi-stage concentrator device is preferably three-stage concentrator devices connected in series.

9. The system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 2, wherein the acidic hydrolyzate of the first transverse unit (4-1) containing a filter element and the third transverse unit (4-3) containing a filter element enters from the inside of the filter element and exits from the outside; The acidic hydrolyzate of the second vertical unit (4-2) containing a filter element and the fourth vertical unit (4-4) containing a filter element enters from the outside of the filter element and exits from the inside.

10. The system for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to any one of claims 2 to 9, characterized in that: The front end and the rear end of the first transverse unit (4-1) containing a filter element and the third transverse unit (4-3) containing a filter element are both provided with a differential pressure transmitter.

11. A method for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of the hydrolyzate, characterized in that: The process carried out using the device according to any one of claims 1 to 10 comprises the following steps: The dimethyldichlorosiloxane hydrolyzate and the water phase enter the static mixer, and after being fully mixed, enter the static mixer, enter the pre-filter for filtration after mixing, and enter the coalescer after filtration. First, the hydrolyzate passes through the first horizontal unit containing the filter element for washing and coalescing, and then the hydrolyzate passes through the second vertical unit containing the filter element upward for repeated coalescing and separation. The separated water phase gathers at the lower end cavity of the first horizontal unit containing the filter element and the second vertical unit containing the filter element, and is transported to the previous coalescer for washing through a delivery pump; the hydrolyzate separated by the second filter element continues to enter the third horizontal unit containing the filter element and the fourth vertical unit containing the filter element for coalescing and separation. The separated water phase gathers at the lower end cavity of the third horizontal unit containing the filter element and the fourth vertical unit containing the filter element. The hydrolyzate separated by the fourth filter element flows out of the equipment from the top outlet of the coalescer to obtain purified dimethyldichlorosilane hydrolyzate.

12. The method for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 11, characterized in that: The acid value of the dimethyldichlorosilane acid hydrolyzate before entering the coalescer is 0.15~0.5%.

13. The method for reducing acid value in the separation and washing process of dimethyldichlorosilane hydrolyzate according to claim 12, characterized in that: When the agglomerator device is a multi-stage agglomerator device connected in series, the purified dimethyldichlorosilane hydrolyzate is mixed with the water phase again and enters the next-stage agglomerator device, and is subjected to agglomeration and separation again to obtain the purified dimethyldichlorosilane hydrolyzate again; the water phase includes process water, circulating dilute acid, and the agglomerated dilute acid of the previous-stage agglomerator.

14. The method for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to claim 13, characterized in that: The coalescer device is a three-stage coalescer device connected in series, and process water is pumped into the inlet of the third-stage coalescer device. After a certain liquid level is reached at the bottom of the connection between the first and second filter elements of the third-stage coalescer, the third-stage circulation pump is started to replenish water to the second-stage coalescer. After a certain liquid level is reached at the bottom of the connection between the first and second filter elements of the second-stage coalescer, the second-stage circulation pump is started to replenish water to the first-stage coalescer. After a certain liquid level is reached at the bottom of the connection between the first and second filter elements of the first-stage coalescer, the first-stage circulation pump is started to replenish water to the front-end system to react with dimethyl. The dimethyldichlorosilane acid hydrolyzate produced by the reaction is filtered through a pre-filter and enters the coalescer for multiple oil-water separations. The hydrolyzate coming out of the coalescer then enters the secondary and tertiary coalescer devices in turn for treatment to obtain purified dimethyldichlorosilane hydrolyzate.

15. The method for reducing acid value in the process of separating and washing dimethyldichlorosilane hydrolyzate according to claim 11, characterized in that: The volume ratio of process water feed to dimethylformamide in the third-stage coalescer device is 0.2~0.3:

1.

16. The method for reducing acid value in the process of separating and washing dimethyldichlorosilane hydrolyzate according to claim 12, characterized in that: The pressure difference of the pre-filter is less than 50Kpa, and the pressure difference of the first and third filter elements is less than 100Kpa.

17. The method for reducing the acid value of dimethyldichlorosilane hydrolyzate during separation and washing of dimethyldichlorosilane hydrolyzate according to any one of claims 11 to 16, characterized in that: After separation and washing by the method, the acid value of the hydrolyzate is lower than 10 PPM, more preferably lower than 5 ppm, and further preferably lower than 1 ppm.

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