Refinery matched coal-to-hydrogen sulfur-tolerant shift methanation integrated process

Abstract

The invention relates to a refinery matched coal-to-hydrogen sulfur-tolerant shift methanation integrated process. According to the invention, the used sulfur-tolerant methanation reactor can meet methanation reactions under different loads so as to effectively avoid the risk of the overtemperature of the bed layer under a low load; compared with a high-temperature circulating methanation technology, the process of the invention has the following advantages that a circulating compressor is canceled so as to reduce the equipment investment and improve the energy recovery rate, and synthesis gassequentially passes through the sulfur-tolerant methanation reactor in a tandem manner so as to simplify the process and the system control and easily achieve good economic benefits; the pressure ofa hydrogen pipe network and the sub-circuit of the sulfur-tolerant methanation reactor are subjected to interlocked control, so that the opening degree of the subcircuit is adjusted in an online manner through the pressure to achieve the stable operation of the hydrogen pipe network so as to ensure the long-period stable operation of the oil refining device; and the load fluctuation of the gasification device due to the fluctuation of the hydrogen pipe network is eliminated so as to easily maintain the long-period stable operation of the gasification device.

Description

technical field [0001] The invention relates to an integrated coal-to-hydrogen and sulfur-resistant transformation methanation process for a refinery. Background technique [0002] In the cost composition of hydrogen production, the cost of raw materials usually accounts for a large proportion. According to the experience of similar projects, when the natural gas price is 3.5 yuan / Nm 3 , and its hydrogen production cost is about 1.1 yuan / Nm 3 ; and under the same scale of hydrogen production, the coal-to-hydrogen route is adopted, and the hydrogen production cost is about 0.61 yuan / Nm based on the raw coal price of 490 yuan / ton 3 . Comparing the two technical routes, the hydrogen cost of the coal-to-hydrogen solution is about 55% of the hydrogen production cost from natural gas. [0003] In addition, my country's natural gas reserves are low in abundance, unevenly distributed, high in production costs, and the contradiction between supply and demand is relatively promine...

AI Technical Summary

Problems solved by technology

However, the existing high-temperature methanation technologies all adopt the design concept of a circulation loop, and return the reacted gas to the inlet through the compressor to reduce the concentration of methane in the raw material gas, so as to achieve the purpose of temperature control. This process route needs to be equipped with a The circulating gas compressor increases the investment and land occupation of the device; at the same time, the circulation process requires condensation and cooling, which causes energy loss and reduces the energy recovery rate; the setting of the circulation loop increases the complexity of temperature control. Changes, increasing the risk of reaction overtemperature, this process is suitable for projects with little change in plant load, such as coal-to-natural (SNG)

[0007]At present, the hydrogen production in the whole hydrogen production process cannot be flexibly adjusted according to the external demand, and the hydrogen production needs to be adjusted by adjusting the gasification load

If the external demand fluctuates frequently, it will cause frequent adjustment of the gasification load, which will affect the long-term stable operation of the device.

The existing supporting hydrogen production units in refineries mainly have the following problems: the hydrogen production cannot be flexibly adjusted according to the pressure of the external hydrogen pipeline network. The hydrogen output can be adjusted online in real time according to the demand of the refinery; the fluctuation of the pressure of the external hydrogen pipeline network will affect the stable operation of the gasification unit; Poor benefit

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