Device and method for removing hydrogen sulfide out of methane by utilizing collagenous fiber/polyester composite material to load Fe(III)

Abstract

The invention provides a device and method for removing hydrogen sulfide out of methane by utilizing collagenous fiber / polyester composite material to load Fe(III). According to the device and the method, collagenous fiber / polyester is taken as a carrier to absorb and load Fe(III); when methane passes through an absorption tower which is full of the collagenous fiber / polyester composite material loaded with Fe(III), H2S in the methane is oxidized into elemental sulfur by Fe(III); and Fe(III) is converted into Fe(II). Under the washing action of a circulation liquid, the elemental sulfur and Fe(II) are washed out from the absorption tower, the elemental sulfur is separated through sedimentation and filtration; when the circulation liquid containing Fe(II) passes through an oxidization tower, Fe(II) is oxidized into Fe(III) by air and reenters the absorption tower through the circulation liquid, so as to remove H2S out of the methane. According to the method, the Fe(III) as a desulfurizing agent can be regenerated, H2S in the methane can be removed to be less than 0.5ppm.

Description

technical field [0001] The invention belongs to the field of biomass renewable energy, and in particular relates to a device and method for removing hydrogen sulfide in biogas by using collagen fiber / polyester composite material to load Fe(III). Background technique [0002] Natural biogas is a low calorific value gas with extremely limited scope of use and low efficiency. The existing biogas industry in some countries mainly uses biogas in improved stoves and engines to generate heat or power as energy for local users. Purified biogas can increase the relative content of methane in its components and increase its calorific value. Purified biogas is currently used as a new type of energy in foreign countries for power supply of pipeline networks or as fuel for motor vehicles. The main process of biogas purification includes: removal of hydrogen sulfide, carbon dioxide, water and other non-combustible impurities. Among them, H 2 S is always present in biogas, although its c...

AI Technical Summary

Problems solved by technology

[0006] At present, the domestic desulfurization technology is relatively mature, and there are many desulfurization methods and desulfurization processes, but all of them have the following disadvantages: the dry desulfurization efficiency is not high, the desulfurizer regeneration is difficult, the sulfur capacity is relatively low, the operation is discontinuous, and the replacement of desulfurizer is labor intensive. Large size and large equipment footprint, etc., mainly suitable for fine desulfurization

The main disadvantage is that a part of sodium carbonate becomes sodium bicarbonate to reduce the absorption efficiency, and a part becomes sulfate and is consumed, so sodium carbonate needs to be replenished in time, thereby increasing labor costs; in actual operation, the absorption of sodium carbonate solution is affected by flow rate, Influenced by factors such as flow rate and temperature, H 2 The solubility of S is likely to be less than 100%; in addition, NaHS is easily formed during desulfurization instead of Na 2 S, NaHS will be regenerated with O 2 The reaction produces sulfate and thiosulfate, and harmful substances are enriched in the absorption solution, which reduces the absorption capacity of the solution, so it is necessary to remove the desulfurization circulating fluid from time to time, wasting a lot of raw and auxiliary materials may also cause secondary environmental pollution

However, this method requires a lower pH value (pH=1.2 to 1.8), and a large amount of acid needs to be added to stabilize the pH, and the conditions to which Thiobacillus ferrooxidans adapt are relatively harsh, resulting in increased instability of the entire system

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