Preparation device and preparation method of shift gas for ammonia synthesis co-production methanol synthesis

Abstract

The invention belongs to a device and method for making shifted gas for synthesis of ammonia synthesis poly-generation methanol. The device comprises a mechanical part and a control part. The mechanical part comprises a gasification washing tower, an outlet of the gasification washing tower is connected with an inlet of a second heat and condensate recycling unit through a pipe, the pipe between the outlet of the gasification washing tower and the second heat and condensate recycling unit is sequentially provided with a fifth tee joint, a first self-regulating valve, a first tee joint and a second tee joint, an outlet of the second heat and condensate recycling unit is connected with an inlet in the middle of a second ammonia-washing tower, and a gas phase outlet in the top of the second ammonia-washing tower is connected with an inlet in the lower portion of a shifted gas washing tower for synthesis of methanol through a pipe; the control part comprises a first online analysis and calculation display instrument, a second online analysis and calculation display instrument, a second self-regulating valve and a third self-regulating valve. The device and method have the advantages that matching efficiency and accuracy are high, a great number of regulating means are adopted, a great amount of high-quality steam is generated, and meanwhile the content of COS in the methanol removing and washing shifted gas is lowered.

Description

technical field [0001] The invention belongs to the technical field of coal chemical production, and in particular relates to a preparation device and a preparation method of shift gas for ammonia synthesis polygeneration methanol synthesis. Background technique [0002] In the present ammonia synthesis and multi-link methanol detection device, when the shift gas for methanol synthesis is produced in the shift section, a certain amount of crude gas is generally used to mix and prepare the gas after the second shift furnace in accordance with (H 2 -CO 2 ) / (CO+CO 2 )=2.05~2.1 shift gas. But in this case, since the CO content of the gas from the second shift furnace is low, the amount of crude gas required is relatively large, so that the crude gas passing through the first shift furnace will be correspondingly reduced, and the high-temperature gas from the first shift furnace will also be reduced. The corresponding reduction will eventually lead to a reduction in the amount...

AI Technical Summary

Problems solved by technology

But in this case, since the CO content of the gas from the second shift furnace is low, the amount of crude gas required is relatively large, so that the crude gas passing through the first shift furnace will be correspondingly reduced, and the high-temperature gas from the first shift furnace will also be reduced. The corresponding reduction will eventually lead to a reduction in the amount of medium-pressure superheated steam generated by heat exchange with high-temperature gas

Under the current situation that the country cancels the preferential electricity price for the chemical fertilizer industry, less production of high-quality steam is extremely unfavorable for enterprises to reduce production costs

At the same time, due to the large amount of crude gas, this part of the gas does not carry the COS carried by the converter, and the COS brought into the methanol wash is more, resulting in methanol washing CO 2 The COS in the product gas exceeds the standard, causing passive production of urea

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