Absorbent for cyclically absorbing sulfur dioxide gas in natural gas tail gas and its application

Abstract

The invention discloses an absorbent for circularly absorbing sulfur dioxide gas in tail gas of natural gas and an application of the absorbent. The absorbent comprises the following components in percentage by mass: 30-60wt% of cyclic tertiary amine compounds, 5-10wt% of a desulfurization fortifier, 10-30wt% of a latent solvent, 0.5-3wt% of an activating agent, 1-2wt% of an antioxidant, 0.5-2wt% of a corrosion inhibitor and the balance of water. The application refers to applying the absorbent to removal of the sulfur dioxide gas in the tail gas of the natural gas at an absorption temperature of 20-70 DEG C. According to the invention, by utilizing the structure characteristics of the cyclic tertiary amine compounds which are high in sulfur dioxide absorption capacity and low in desorption energy consumption, and adding corresponding auxiliary agents at the same time, the absorption of absorption liquid to sulfur dioxide has high efficiency and specificity; and the absorbent can selectively remove SO2 from the tail gas of the natural gas, so as to greatly reduce the gas purification cost, and facilitate follow-up utilization of recycled acid gas.

Description

technical field [0001] The invention belongs to the technical field of environmental protection and gas purification, and more specifically relates to an absorbent for circularly absorbing sulfur dioxide gas in natural gas tail gas and its application. Background technique [0002] Sulfur dioxide is a colorless gas with a strong pungent smell. It is one of the main air pollutants at present. It will cause great harm to human health and the environment. It is also one of the main causes of severe weather such as acid rain and smog in recent years. With the rapid development of my country's economy, the scale of major industries such as thermal power, mineral smelting, and oil and gas extraction and refining has increased year by year. In the production process, SO 2 Mainly polluting gas emissions surged simultaneously. Since 1995, my country surpassed Europe and the United States to become the world's SO 2 The country with the largest emission, the urban ambient air SO with...

AI Technical Summary

Problems solved by technology

[0004] above SO 2 The absorbent is absorbing SO 2 There are following problems during: (1) acid-base SO 2 The absorbing fluid is absorbing SO 2 At the same time, it is easy to cause corrosion of the equipment; (2) the N-H bond is easily oxidized, thereby reducing the absorption capacity of the absorbent; (3) when absorbing SO 2 At the same time, it does not effectively avoid the absorption of CO in the exhaust gas 2 The absorption of acid gas will make SO 2 The absorption capacity of the absorbent becomes smaller, and the absorption capacity of the absorbent for SO 2 The absorption efficiency will decrease quickly, resulting in an increase in solvent circulation, which is also not conducive to the subsequent utilization of regenerated acid gas; (4) The absorbent absorbs sulfur dioxide to form a relatively stable structure, and the high desorption temperature results in high energy consumption

So far, there has been no report on SO in natural gas tail gas 2 Absorbent