Synthetic gas catalytic methanation method and device

Abstract

Belonging to the field of chemical reaction process technological design and its application, the invention specifically relates to a synthetic gas catalytic methanation method and device. The synthetic gas catalytic methanation method comprises the steps of: 1) inputting synthesis gas into a concurrent flow upward conveying bed reactor bottom, conducting fully mixing preheating with methanation catalyst particles entering the reactor bottom to reach a catalyst activation temperature, and then carrying out methanation reaction; and 2) at the end of the methanation reaction, letting the product gas and catalyst particles output from the conveying bed directly enter a gas-solid separator to conduct rapid separation, thus obtaining the product gas. According to the invention, by adopting the concurrent flow upward conveying bed as the methanation reactor, the effective utilization rate of the catalyst is improved. With the invention, the pressure drop of the whole process is significantly reduced, and the product gas and catalyst particles obtained by separation of the gas-solid separator can be subjected to heat exchange respectively through a heat exchanger so as to generate superheated steam, thus enhancing the energy utilization rate of the whole process.

Description

technical field [0001] The invention belongs to the field of chemical reaction process process design and its application. Specifically, it relates to a method and device for catalytic methanation of syngas using a low-pressure drop transport bed. Further, it is a new process method and realization of methanation of syngas Apparatus for process methods. Background technique [0002] China's energy has the characteristics of "rich coal, poor oil, and little gas". Coal occupies a major position in my country's primary energy consumption structure. Compared with coal-to-methanol, coal-to-dimethyl ether, coal direct liquefaction and other technologies, coal-to-natural gas has high energy efficiency (above 60%), less water consumption per unit calorific value, CO 2 Low emissions and high utilization rate of waste heat (by-product high temperature and high pressure steam). Relying on this, if coal is used as raw material to replace natural gas through methanation reaction, while...

AI Technical Summary

Problems solved by technology

In the 1970s, Germany’s Linda Company developed a new type of coal-to-natural gas technology. In this process, the main methanation reactor was designed as an isothermal fixed-bed reactor, and heat exchange tubes were installed inside the catalyst bed to convert the reaction The heat is removed to produce high-pressure steam so that the reaction proceeds under isothermal conditions, but the built-in heat exchanger is for a fixed-bed catalyst bed, the catalyst particles have a large heat transfer resistance, and local reaction will still occur when the reaction is violent or the reaction space velocity is large. Overheating leads to catalyst deactivation, so its production efficiency is greatly limited

Both of these two methods fix the catalyst in the reactor, but the flow and collision of the gas and the inert heat carrier or adsorbent will inevitably cause the abrasion of the catalyst, which eventually leads to the mixing of the catalyst particles and the inert heat carrier, which is difficult to recover

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