CN-115895740-B - Coke oven gas deamination agent and preparation method thereof

Abstract

The invention discloses a deamination agent for coke oven gas and a preparation method thereof, wherein the deamination agent takes zinc and copper metal salts as active components, the nickel and cobalt metal salts are used as auxiliary components, and magnesia-alumina spinel prepared from alumina and magnesia is used as a carrier. The deamination agent has the characteristics of high deamination activity, high penetrating ammonia capacity, regeneration and the like, is used for gas phase deamination, is particularly suitable for a coke oven gas purification process, and can be used for removing the ammonia content to 0.1ppm.

Inventors

• ZHANG XIANMAO
• ZHOU ZHENG
• ZHENG FENGWEI
• WANG YU
• WANG ZE
• WANG GUOXING
• SHEN KANGWEN
• WANG HAIYANG
• PENG MIAO
• CHEN KAI

Assignees

• 武汉科林化工集团有限公司

Dates

Publication Date

20260505

Application Date

20230106

Claims (4)

1. 1. A preparation method of a coke oven gas deamination agent is characterized in that the deamination agent takes magnesia-alumina spinel as a carrier to load active components and auxiliary agents, wherein the active components are zinc metal salts and copper metal salts, the auxiliary agents are one or more of nickel metal salts and cobalt metal salts, the mass fraction of zinc salts is 14-18%, the mass fraction of copper salts is 7-10%, and the mass fraction of auxiliary agents is 2-4% based on the mass of the carrier, and the preparation method comprises the following steps: (1) Finely grinding brucite ore to 400 meshes, roasting for 3 hours at 400 ℃, adding the fine powder into deionized water while the fine powder is hot, quenching, pulping and uniformly mixing, standing for 24 hours, scraping and drying at 120 ℃ and flash drying at 180 ℃ to obtain magnesium stone powder; (2) Weighing macroporous pseudo-boehmite, small pore pseudo-boehmite, magnesium stone powder, quick-release powder and guar gum according to a certain proportion, dry-mixing uniformly, adding aqueous solution of fluxing agent, kneading, extruding and molding, sealing and preserving for 24-48 h, roasting for 4h at 400-450 ℃, soaking in 80 ℃ water for 2h, filtering, drying at 120 ℃, and roasting for 4-6 h at 600-650 ℃ to obtain a carrier; the fluxing agent is ternary fused salt of 35% zinc sulfate, 58% aluminum chloride and 7% sodium phosphate in mass percent; (3) Weighing copper, zinc, nickel and cobalt salts according to a certain proportion, dissolving in deionized water, heating to 50-60 ℃ until the metal salts are completely dissolved, and regulating the pH to 3-4 by sulfuric acid or phosphoric acid to obtain Cu-Zn-Co-Ni salt impregnating solution; (4) And (3) loading the impregnating solution obtained in the step (3) on the carrier obtained in the step (2) by adopting an isovolumetric impregnation method, wherein the impregnation time is 10-24 h, and the deamination agent is obtained by drying at 80-100 ℃.
2. 2. The preparation method of the deamination agent for coke oven gas, which is disclosed in claim 1, is characterized in that copper, zinc, cobalt and nickel salts in the step (3) are sulfate or metal chloride, and the soaking solution in the step (2) is used for preparing the Cu-Zn-Co-Ni salt soaking solution in the step (3).
3. 3. The preparation method of the deamination agent for coke oven gas according to claim 1, wherein the ammonia capacity is more than or equal to 8.0%, and the ammonia capacity of the regenerant is more than or equal to 7.5%.
4. 4. The method for preparing the deamination agent for coke oven gas according to claim 1, wherein the deamination agent regeneration process is nitrogen or air or water vapor atmosphere, 140-160 ℃ per 5h, 180 ℃ per 1h, gas phase airspeed of 2000h -1 , and the regenerated gas is condensed by water and ammonia water is a byproduct.

Description

Coke oven gas deamination agent and preparation method thereof Technical Field The invention relates to a deamination agent for coke oven gas and a preparation method thereof, belonging to the field of coke oven gas purification. Background The iron and steel industry drives the development of coking industry, and makes China the first country of coke production. Tamping coking is a new coking process developed in the present year, and is suitable for the national conditions of strong caking coal shortage in China. More than 400 raw coke gas can be produced per ton of coke, and the main components of the raw coke gas are methane and hydrogen, so that the raw coke gas has rich energy and chemical utilization value. The coke oven gas is comprehensively utilized, pollution is reduced, the method accords with the national industrial development requirements of building a saving type society and creating green industry and recycling economy. Raw gas enters a gas collecting pipe from a rising pipe, a large amount of circulating water is sprayed into the gas collecting pipe, the temperature is reduced from about 700 ℃ to 80-85 ℃, a large amount of tar, naphthalene, ammonia, hydrogen cyanide, phenol and other impurities are cooled down, circulating ammonia water and raw gas flow into a primary cooler in parallel, and the gas is cooled and condensed continuously. The temperature of the gas discharged from the primary cooler is 21-23 ℃, coke oil mist is removed in the section tar precipitator, then the gas is pressurized by a blower, hydrogen sulfide is removed in a desulfurizing tower, ammonia is recovered in an ammonium sulfate device, benzene is recovered in a benzene eluting device, part of organic sulfur is removed, and the purified gas is called coke oven gas. The comprehensive utilization way of the coke oven gas can be divided into three types, namely fuel, reducing agent and chemical raw material. Among them, the coke oven gas is widely used as chemical raw material to synthesize methanol, and can be further used for preparing chemical products such as olefin, formaldehyde, dimethyl ether, etc. The technology for preparing the methanol from the coke oven gas mainly comprises the steps of tar removal by filtration, pre-desulfurization, fine desulfurization, alkane conversion, methanol synthesis, rectification and the like. The exceeding of ammonia content in coke oven gas can cause the change of structural attribute of the iron-molybdenum hydrogenation catalyst and the loss of active sites. The molybdenum in the iron molybdenum hydrogenation catalyst and the cobalt molybdenum hydrogenation catalyst react with ammonia to form salts, the generated salts are attached to the surfaces of the iron molybdenum hydrogenation catalyst and the cobalt molybdenum hydrogenation catalyst to block the pores and active sites of the catalyst, so that the catalyst is deactivated and irreversible, and meanwhile, the ammonium salt can cause equipment corrosion, damage and the like. When a trace amount of water exists, ammonia and copper in the methanol catalyst generate copper ammonia complex ions to cause copper loss, so that the methanol catalyst is deactivated. Therefore, the fixed bed deamination tower is arranged in front of the coke oven gas buffer gas cabinet, which can prevent ammonium salt crystals from corroding equipment and blocking pipelines, avoid ammonia poisoning of iron-molybdenum, cobalt-molybdenum hydrodesulfurization catalysts and methanol synthesis catalysts, and improve the service life of the catalysts and the stability of production systems. Disclosure of Invention The invention aims to provide a coke oven gas deaminizing agent and a preparation method thereof, wherein ammonia gas has toxic influence on iron-molybdenum hydrogenation and cobalt-molybdenum hydrogenation catalysts of a fine desulfurization section and copper-based catalysts of a methanol synthesis section according to the current technological situation of synthesizing methanol from coke oven gas. The deaminizing agent takes magnesium aluminate spinel as a carrier to carry active components and auxiliary agents, wherein the active components are zinc metal salts and copper metal salts, the auxiliary agents are one or more of cobalt metal salts and nickel metal salts, and the mass fraction of zinc salts is 14-18%, the mass fraction of copper salts is 7-10%, and the mass fraction of auxiliary agents is 2-4% based on the mass of the carrier. The preparation method of the deamination agent comprises the following steps: and weighing the macroporous pseudo-boehmite, the small pore pseudo-boehmite, the magnesium stone powder, the quick-release powder and the guar gum according to a certain proportion, dry-mixing uniformly, adding an aqueous solution of a fluxing agent, kneading, extruding and molding, sealing and preserving for 24-48 hours, roasting for 4 hours at 400-450 ℃, soaking in 80 ℃ for 2 hours, filtering, drying at 120 ℃, and roasting for