Treatment of frequent blockage of inlet filter screen of methanol synthesis gas compressor

The relationship between return flow of main tower and acid value is replaced by stainless steel pipeline.

• A double filter screen is installed at the inlet of the compressor to realize on-line switching when one filter screen is blocked.
• Before replacement, start the ventilation fan of the plant and open the surrounding windows to prevent the accumulation of toxic gas and combustible gas.
• During pressure equalizing and replacement, fully open the primary pressure equalizing valve, and then slowly slightly open the secondary pressure equalizing valve.
• It can be switched only when the oxygen content in the replacement gas is less than 0.5. When putting into use, open the filter screen rear valve first, and then the filter screen front valve.
• Shut down the front and rear valves of the filter screen, close the primary and secondary pressure equalizing valves, and fully open the water diversion and pressure relief valve.
• The filter screen switching was successfully implemented, and the differential pressure after switching was 0.004mpa. The blocked filter screen was cleaned and standby.

The success of this technical transformation not only solves a bottleneck problem restricting the long-term operation of Tianye methanol plant, but also protects the synthetic catalyst, ensures the safe operation of the compressor, creates benefits for the company, and also provides practical experience that can be used for reference for dealing with similar problems in the future, which is of great significance.

The parameters such as alkali addition amount, tower kettle temperature, non condensable gas temperature and reflux tank temperature of pre distillation column directly affect the acidity of methanol products, which should be optimized in production.

Controlling the reflux ratio and pressure of the main distillation column, preventing negative pressure in the main distillation column, reducing various side reactions of methanol synthesis, reducing the generation of water, and reducing the pressure of crude methanol flash tank are effective means to control the acidity of methanol products.

Whether the vent volume of non condensable gas meets the conditions is also an important factor affecting the acidity of refined methanol products.