The cooling of the methanol synthesis tower outlet gas is an important part of the methanol production process, the cooling effect is not good, the gas temperature is high, it will increase the circulating gas in the methanol gas partial pressure, resulting in the gaseous methanol can not be completely condensed into the synthesis The increase of methanol content in the tower gas leads to excessive turbine load. In order to solve this problem, Daqing Oilfield Chemical Industry Group's methanol branch company, based on the principle that the methanol gas partial pressure decreases with decreasing temperature, takes chilled water from the refrigeration provided by the chiller, and then cools the synthetic circulating gas through chilled water. More methanol gas condenses and liquefies to achieve the purpose of increasing methanol production and optimizing the recycle gas composition.
The traditional method of reducing the methanol content of the recycle gas is to separate the liquid methanol that has condensed in the recycle gas by adopting a high-efficiency separation device, but this method can only separate the methanol under saturation temperature and pressure. The methanol separation system adopted by the methanol branch of Daqing Oilfield Chemical Group adopts another approach, which is to reduce the temperature of circulating gas and further reduce the methanol content in the recycle gas. This process route needs to perform simulation calculations on the parameters of the synthetic system after the assumption is implemented before the transformation, and then obtains new material balance and heat balance data re-established by the synthesis system, in order to judge the impact of the project implementation. This will provide a feasibility basis for the project's on-site implementation and economic benefit evaluation.
The branch company implemented the methanol synthesis system refrigeration separation technology, the synthesis system of various process parameters have been greatly improved, the synthesis of circulating gas temperature from the original 42 °C down to 10 °C ~ 12 °C, circulating gas methanol content by 0.71% To 0.15%, under the same working conditions, the device can produce 20 tons of crude methanol, equivalent to 16 tons of refined methanol, and 5,000 tons of refined methanol per year. The annual comprehensive economic benefit is 5,112,700 yuan.
The effect of this technological transformation is that the methanol content in the tower tower gas is reduced, the synthesis reaction is conducive to the positive reaction direction, and the catalyst activity can be more effectively utilized; after the synthesis cycle gas temperature is lowered, the synthesis tower The amount of circulation is also reduced, so the steam power consumption of the turbine is also reduced, which can reduce the amount of steam supply outside the low pressure steam network; due to the reduction of the circulation, the combustion of the synthetic release air into the reformer is reduced; due to the synthesis cycle With the reduction of quantity, the front conversion system can increase approximately 400 standard cubic meters of raw natural gas per hour in a safe range, increasing the crude methanol production, lowering the average molecular weight of the recycle gas, lowering the power consumption of the turbine, and the dry gas seal of the recycle compressor. System operation is optimized.
Methanol synthesis system refrigerated separation technology transformation Relying on the original equipment of the dimethanol plant synthesis system, the goal of increasing methanol production, lowering production costs and optimizing process parameters on the basis of adding a set of refrigeration units is a multiple purpose The transformation measures.
The traditional method of reducing the methanol content of the recycle gas is to separate the liquid methanol that has condensed in the recycle gas by adopting a high-efficiency separation device, but this method can only separate the methanol under saturation temperature and pressure. The methanol separation system adopted by the methanol branch of Daqing Oilfield Chemical Group adopts another approach, which is to reduce the temperature of circulating gas and further reduce the methanol content in the recycle gas. This process route needs to perform simulation calculations on the parameters of the synthetic system after the assumption is implemented before the transformation, and then obtains new material balance and heat balance data re-established by the synthesis system, in order to judge the impact of the project implementation. This will provide a feasibility basis for the project's on-site implementation and economic benefit evaluation.
The branch company implemented the methanol synthesis system refrigeration separation technology, the synthesis system of various process parameters have been greatly improved, the synthesis of circulating gas temperature from the original 42 °C down to 10 °C ~ 12 °C, circulating gas methanol content by 0.71% To 0.15%, under the same working conditions, the device can produce 20 tons of crude methanol, equivalent to 16 tons of refined methanol, and 5,000 tons of refined methanol per year. The annual comprehensive economic benefit is 5,112,700 yuan.
The effect of this technological transformation is that the methanol content in the tower tower gas is reduced, the synthesis reaction is conducive to the positive reaction direction, and the catalyst activity can be more effectively utilized; after the synthesis cycle gas temperature is lowered, the synthesis tower The amount of circulation is also reduced, so the steam power consumption of the turbine is also reduced, which can reduce the amount of steam supply outside the low pressure steam network; due to the reduction of the circulation, the combustion of the synthetic release air into the reformer is reduced; due to the synthesis cycle With the reduction of quantity, the front conversion system can increase approximately 400 standard cubic meters of raw natural gas per hour in a safe range, increasing the crude methanol production, lowering the average molecular weight of the recycle gas, lowering the power consumption of the turbine, and the dry gas seal of the recycle compressor. System operation is optimized.
Methanol synthesis system refrigerated separation technology transformation Relying on the original equipment of the dimethanol plant synthesis system, the goal of increasing methanol production, lowering production costs and optimizing process parameters on the basis of adding a set of refrigeration units is a multiple purpose The transformation measures.