Methylsiloxane cracking tail gas purification treatment system and treatment method

[0027] Example 1

[0028] like figure 1 As shown, this embodiment provides a methylsiloxane pyrolysis tail gas purification treatment system, including an absorption liquid buffer tank 1, an absorption liquid circulation pump 2, an absorption liquid condenser 3, a gas-liquid separator 4 and a first vacuum pump 5 , the absorption liquid buffer tank 1, the absorption liquid circulating pump 2, the absorption liquid condenser 3 and the gas-liquid separator 4 are connected in turn to form a closed loop, the absorption liquid buffer tank 1 and the first vacuum pump 5 form a circulation loop, and the first vacuum pump 5 and the absorption liquid A first vacuum pump buffer tank 51 is arranged between the liquid buffer tank 1, a balance pipe 11 is arranged between the absorption liquid buffer tank 1 and the first vacuum pump 5, and also includes a second vacuum pump 6, the second vacuum pump 6 and the first vacuum pump 5 In parallel, a second vacuum pump buffer tank 61 is arranged between the second vacuum pump 6 and the absorption liquid buffer tank 1 , a pressure gauge 12 is arranged at the absorption liquid buffer tank 1 , and a thermometer 31 is arranged at the absorption liquid condenser 3 .

[0029] Example 2

[0030] This embodiment provides a method for purifying and treating methylsiloxane cracking tail gas, that is, a method for using the methylsiloxane cracking tail gas purification and treatment system provided in Example 1, as follows:

[0031] In the process of use, it is necessary to inject the absorption liquid (D in the absorption liquid) into the absorption liquid buffer tank in advance. 5 When the liquid level of the absorption liquid buffer tank reaches 60%, start the absorption liquid circulation pump to circulate the system, and the absorption liquid flows through the absorption liquid condenser and gas-liquid separator, and finally returns to the absorption liquid liquid buffer tank. After normal circulation, the pressure of the absorption liquid buffer tank is pumped to a negative pressure of more than 70kPa through the balance pipe at the top of the absorption liquid buffer tank. After the pressure reaches the condition, the vacuum line of the methylsiloxane cracking system is slowly merged into the tail gas absorption system. . In the process of circulating absorption, it is necessary to ensure that the outlet temperature of the absorption liquid condenser is between 30-40 °C, and the absorption liquid in the absorption liquid buffer tank is regularly sampled for analysis. 5 When the content is less than 50%, it is necessary to replace the absorbing liquid in time to prevent the 4 The content is too high, causing the absorption liquid to block in the condenser or other locations. In addition, it is necessary to ensure that the circulation volume of the absorption liquid is sufficient to absorb the pyrolysis tail gas, and the minimum circulation volume is not less than 20m3/h. If the circulation volume is too low, it is necessary to check whether the absorption liquid is blocked by crystallization.