CN-122006604-A - Cold hydrogenation production process and device

CN122006604ACN 122006604 ACN122006604 ACN 122006604ACN-122006604-A

Abstract

The embodiment of the application provides a cold hydrogenation production process and a device, wherein the process comprises the steps of introducing mixed materials of hydrogen, silicon tetrachloride and silicon powder into a fluidized bed reactor for hydrogenation reaction to generate chlorosilane mixed gas, introducing the chlorosilane mixed gas into a tube-winding heat exchanger for primary cooling, removing silicon powder from the chlorosilane mixed gas output from the tube-winding heat exchanger through a filtering unit, introducing the chlorosilane mixed gas output from the filtering unit into the heat exchanger for secondary cooling, quenching and washing the chlorosilane mixed gas output from the heat exchanger, and condensing and separating the quenched and washed chlorosilane mixed gas to obtain chlorosilane and hydrogen. The application adopts the coiled tube heat exchanger and immediately filters after cooling, thereby effectively solving the problems of easy blockage and low heat transfer efficiency of the traditional tubular heat exchanger, improving the heat energy recovery efficiency, reducing the energy consumption of the system and prolonging the running period of equipment.

Inventors

WEI JINRUI
YANG ZHOU
YAN HUICHENG
HU WEI
LIU XIAOTING
ZHOU YOU

Assignees

青海丽豪清能股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260209

Claims (10)

1. A cold hydrogenation production process, which comprises the steps of, characterized by comprising the following steps: Introducing a mixed material of hydrogen, silicon tetrachloride and silicon powder into a fluidized bed reactor for hydrogenation reaction to generate chlorosilane mixed gas; introducing the chlorosilane mixed gas into a coiled pipe heat exchanger to perform primary cooling; the chlorosilane mixed gas output from the coiled tube heat exchanger is filtered by a filtering unit to remove silicon powder; introducing the chlorosilane mixed gas output from the filtering unit into a heat exchanger for secondary cooling; Quenching and washing the chlorosilane mixed gas output from the heat exchanger; condensing and separating the chlorsilane mixed gas after quenching and washing to obtain chlorsilane and hydrogen.
2. The cold hydrogenation production process according to claim 1, wherein said passing said chlorosilane mixture gas output from said tube-around heat exchanger through a filter unit to remove silicon powder comprises: the filtering unit comprises a cyclone separator and a silica powder filter which are sequentially communicated; introducing the chlorosilane mixed gas output by the tube-winding heat exchanger into the cyclone separator for gas-solid separation to remove silicon powder; And introducing the chlorosilane mixed gas subjected to gas-solid separation into the silicon powder filter to remove silicon powder.
3. A cold hydrogenation production process according to claim 2, wherein said filtration unit comprises a first silicon powder receiver in communication with said cyclone separator and a second silicon powder receiver in communication with said silicon powder filter; And the silicon powder removed by the cyclone separator and the silicon powder filter enters the first silicon powder receiver and the second silicon powder receiver.
4. The cold hydrogenation production process according to claim 1, wherein said quenching washing said chlorosilane mixture gas outputted from said heat exchanger comprises: Introducing the chlorosilane mixed gas output from the heat exchanger into a quenching tower for quenching and washing; spraying chlorosilane liquid condensed by adopting a cold hydrogenation process; and spraying medium is uniformly sprayed into the quenching tower through the multilayer distributor, so that cooling and impurity removal are realized.
5. The cold hydrogenation production process according to claim 4, wherein the impurities are sent to a filter for filtration and then sent to a slurry system.
6. The cold hydrogenation production process according to claim 4, wherein said condensing and separating said chlorosilane mixture after quenching and washing comprises: the chlorosilane mixed gas output from the top outlet of the quenching tower sequentially passes through a circulating hydrogen heat exchanger, a silicon tetrachloride heat exchanger, an air cooler, a circulating water heat exchanger, a chilled water heat exchanger, an intermediate heat exchanger and a terminal condenser for multistage condensation separation; The intermediate heat exchanger and the terminal condenser output hydrogen; And discharging condensate separated by the multistage condensation to a hydrogenated liquid storage tank.
7. The cold hydrogenation production process according to claim 6, wherein the hydrogen discharged from said intermediate heat exchanger and said terminal condenser is sent to a recycle hydrogen buffer tank; the circulating hydrogen buffer tank is sequentially communicated with the circulating hydrogen compressor and the circulating hydrogen heat exchanger.
8. The cold hydrogenation production process according to claim 1, wherein the step of introducing the mixture of hydrogen, silicon tetrachloride and silicon powder into the fluidized bed reactor to carry out hydrogenation reaction comprises: And sequentially passing the mixed material through a quenching tower top heat exchanger, a silicon tetrachloride vaporizer, a reaction feeding heater and an electric heater to carry out multistage heating and vaporization.
9. The cold hydrogenation production process according to claim 8, wherein the external silicon powder is conveyed to the cold hydrogenation reactor through a silicon powder collector and a silicon powder feeder to carry out hydrogenation reaction with the hydrogen and the silicon tetrachloride after the multi-stage heating.
10. Cold hydrogenation production apparatus, characterized in that cold hydrogenation production is carried out using the cold hydrogenation production process according to any one of the preceding claims 1 to 9, comprising: The flow passage of the coiled pipe heat exchanger is of a spiral or corrugated structure and is used for carrying out graded heating on the mixed gas of hydrogen and silicon tetrachloride; the fluidized bed reactor is connected with the output end of the coiled tube heat exchanger and is used for carrying out hydrogenation reaction under the action of a catalyst; the filtering structure comprises a cyclone separator and a silica powder filter which are sequentially communicated and is used for removing silica powder in the mixed gas; the heat exchanger is communicated with the output end of the filtering structure and is used for cooling the filtered mixed gas; and the quenching tower is communicated with the output end of the heat exchanger and is used for quenching and washing the mixed gas.

Description

Cold hydrogenation production process and device Technical Field The application relates to the technical field of polysilicon production, in particular to a cold hydrogenation production process and a cold hydrogenation production device. Background In the cold hydrogenation process, the high temperature mixed gas at the outlet of the reactor is subjected to heat exchange, separation and washing to recover useful components and remove impurities. The heat energy recovery efficiency and the equipment operation stability in the link are directly related to the energy consumption and the economy of the whole process. In the scheme of the related technology, high-temperature reaction gas firstly exchanges heat and cools through a two-stage tube type heat exchanger, then most silicon powder is removed through a cyclone separator and a silicon powder filter, then enters a quenching tower for spray washing, and finally, chlorosilane and hydrogen are recovered through a multistage condensing system. However, by adopting the scheme of the related technology, the heat exchange efficiency of the shell and tube heat exchanger is insufficient, a large amount of high-temperature reaction heat cannot be effectively recycled, so that the dependence of the subsequent technology on external heat sources such as an electric heater is aggravated, and the overall power consumption is higher. Meanwhile, fine silicon powder entrained in the reaction gas is extremely easy to deposit on the pipe wall of the shell and tube heat exchanger, equipment scaling, blocking and accelerated abrasion are caused, frequent shutdown and cleaning are needed, and the continuity and stability of production are seriously affected. Disclosure of Invention The embodiment of the application provides a cold hydrogenation production process and a cold hydrogenation production device, which are used for improving heat exchange efficiency, reducing energy consumption and solving the problems of equipment abrasion and blockage so as to meet the high-efficiency, energy-saving and stable requirements of industrial production. In a first aspect, embodiments of the present application provide a cold hydrogenation production process, comprising: Introducing a mixed material of hydrogen, silicon tetrachloride and silicon powder into a fluidized bed reactor for hydrogenation reaction to generate chlorosilane mixed gas; introducing the chlorosilane mixed gas into a coiled pipe heat exchanger to perform primary cooling; the chlorosilane mixed gas output from the coiled tube heat exchanger is filtered by a filtering unit to remove silicon powder; introducing the chlorosilane mixed gas output from the filtering unit into a heat exchanger for secondary cooling; Quenching and washing the chlorosilane mixed gas output from the heat exchanger; condensing and separating the chlorsilane mixed gas after quenching and washing to obtain chlorsilane and hydrogen. In one possible embodiment, the step of removing silicon powder from the chlorosilane mixture gas output from the coiled tube heat exchanger through a filter unit includes: the filtering unit comprises a cyclone separator and a silica powder filter which are sequentially communicated; introducing the chlorosilane mixed gas output by the tube-winding heat exchanger into the cyclone separator for gas-solid separation to remove silicon powder; And introducing the chlorosilane mixed gas subjected to gas-solid separation into the silicon powder filter to remove silicon powder. In one possible embodiment, the filtration unit comprises a first silicon powder receiver in communication with the cyclone separator and a second silicon powder receiver in communication with the silicon powder filter; And the silicon powder removed by the cyclone separator and the silicon powder filter enters the first silicon powder receiver and the second silicon powder receiver. In one possible embodiment, the quenching the chlorosilane mixture gas output from the heat exchanger comprises: Introducing the chlorosilane mixed gas output from the heat exchanger into a quenching tower for quenching and washing; spraying chlorosilane liquid condensed by adopting a cold hydrogenation process; and spraying medium is uniformly sprayed into the quenching tower through the multilayer distributor, so that cooling and impurity removal are realized. In one possible embodiment, the impurities are fed to a filter for filtration and then fed to a slurry system. In one possible embodiment, the condensing and separating the chlorosilane mixture after quenching and washing includes: the chlorosilane mixed gas output from the top outlet of the quenching tower sequentially passes through a circulating hydrogen heat exchanger, a silicon tetrachloride heat exchanger, an air cooler, a circulating water heat exchanger, a chilled water heat exchanger, an intermediate heat exchanger and a terminal condenser for multistage condensation separation; The intermediate heat exc