Method for inhibiting the rise of pressure difference in alkali washing tower of methanol to low-carbon olefins

Abstract

The invention relates to the field of methanol-to-low olefin production, and discloses a method for inhibiting the increase of pressure difference of methanol-to-low olefin alkali washing tower. The method comprises: injecting an inhibitor composition into an alkali washing tower of a methanol-to-light olefin separation unit, wherein the inhibitor composition contains an anti-polymerization agent, an antioxidant, an anti-corrosion agent, a surfactant, a cosolvent and a solvent, wherein , the anti-polymerization agent is an alcohol amine compound and / or a hydrazine compound, and the antioxidant is a mixture of diisopropanolamine, tert-butyl-p-hydroxyanisole and N,N-di-sec-butyl-p-phenylenediamine one or more of. The method can effectively suppress the increase of pressure difference in the alkali washing tower of methanol to light olefins.

Description

technical field

[0001] The invention relates to the field of methanol-to-low olefin production, in particular to a method for inhibiting the increase of pressure difference of methanol-to-low olefin alkaline washing tower. Background technique

[0002] Methanol-To-Olefin (MTO for short) refers to the production of methanol from natural gas or coal as raw material through synthesis gas, and then methanol generates low-carbon olefins such as ethylene and propylene under the action of a catalyst. Its products have been proved to be fully applicable. In the production of polyolefins and other products. MTO technology has opened up a new process route for producing chemical products from unconventional petroleum resources, and has become the research focus of olefin synthesis from unconventional petroleum resources.

[0003] Methanol to light olefins is based on SAPO-34 molecular sieve catalyst and catalyst continuous reaction-regeneration fluidization technology, which converts...

Examples

preparation example Construction

[0038] According to the method of the present invention, preferably, the preparation method of the inhibitor composition includes: mixing a cosolvent and an antioxidant and first stirring to obtain a mixture; and then mixing the mixture with a solvent, an anticorrosion agent, and an antipolymerization agent in sequence. Mix with surfactant and stir a second time.

[0039] According to the method of the present invention, preferably, the conditions for the first stirring include: a temperature of 10-48° C. and a time of 0.2-0.5 h.

[0040] According to the method of the present invention, preferably, the conditions for the second stirring include: a temperature of 10-48° C. and a time of 0.5-2.5 h.

specific Embodiment approach

[0041] According to a specific embodiment of the present invention, a method for preparing an inhibitor composition includes: mixing a cosolvent and an antioxidant, and stirring at 10-48° C. for 0.2-0.5 h to obtain a mixture; and then mixing the The mixture is sequentially mixed with a solvent, an anti-corrosion agent, an anti-polymerization agent and a surfactant, and the inhibitor composition is obtained after stirring at 10-48° C. for 0.5-2.5 h.

[0042] The present invention will be described in detail below by means of examples.

[0043] % of polymer content in lye = weight of dry material (M 1 ) / weight of the sample (M 0 )×100% (Formula I)

Embodiment 1

[0045] (A) Mix 25 parts by weight of propylene glycol and 6 parts by weight of tert-butyl-p-hydroxyanisole, and stir at 25° C. for 0.4 h to obtain a mixture; mix the mixture with 50 parts by weight of deionized water, 10 Triisopropanolamine in parts by weight, ethanolamine in 30 parts by weight, hydrazine hydrate in 6 parts by weight, and sodium dodecyl sulfate in 8 parts by weight were mixed, and stirred at 25° C. for 2 hours to obtain an inhibitor composition, denoted as is C1, wherein the ammonia nitrogen content in the inhibitor composition C1 is 3.2 mg / L.

[0046] (B) The operating conditions of the alkaline washing tower include: the temperature at the top of the tower is 42° C., and the pressure at the top of the tower is 1.35 MPa.

[0047] The flow rate of the product gas at the inlet of the caustic washing tower is 90t / h, and the mass concentration of oxygen-containing compounds in the product gas at the inlet of the caustic washing tower is 100 ppm, wherein the oxyge...

technical field

[0001] The invention relates to the field of methanol-to-low olefin production, in particular to a method for inhibiting the increase of pressure difference of methanol-to-low olefin alkaline washing tower. Background technique

[0002] Methanol-To-Olefin (MTO for short) refers to the production of methanol from natural gas or coal as raw material through synthesis gas, and then methanol generates low-carbon olefins such as ethylene and propylene under the action of a catalyst. Its products have been proved to be fully applicable. In the production of polyolefins and other products. MTO technology has opened up a new process route for producing chemical products from unconventional petroleum resources, and has become the research focus of olefin synthesis from unconventional petroleum resources.

[0003] Methanol to light olefins is based on SAPO-34 molecular sieve catalyst and catalyst continuous reaction-regeneration fluidization technology, which converts...

Examples

preparation example Construction

[0038] According to the method of the present invention, preferably, the preparation method of the inhibitor composition includes: mixing a cosolvent and an antioxidant and first stirring to obtain a mixture; and then mixing the mixture with a solvent, an anticorrosion agent, and an antipolymerization agent in sequence. Mix with surfactant and stir a second time.

[0039] According to the method of the present invention, preferably, the conditions for the first stirring include: a temperature of 10-48° C. and a time of 0.2-0.5 h.

[0040] According to the method of the present invention, preferably, the conditions for the second stirring include: a temperature of 10-48° C. and a time of 0.5-2.5 h.

specific Embodiment approach

[0041] According to a specific embodiment of the present invention, a method for preparing an inhibitor composition includes: mixing a cosolvent and an antioxidant, and stirring at 10-48° C. for 0.2-0.5 h to obtain a mixture; and then mixing the The mixture is sequentially mixed with a solvent, an anti-corrosion agent, an anti-polymerization agent and a surfactant, and the inhibitor composition is obtained after stirring at 10-48° C. for 0.5-2.5 h.

[0042] The present invention will be described in detail below by means of examples.

[0043] % of polymer content in lye = weight of dry material (M 1 ) / weight of the sample (M 0 )×100% (Formula I)

Embodiment 1

[0045] (A) Mix 25 parts by weight of propylene glycol and 6 parts by weight of tert-butyl-p-hydroxyanisole, and stir at 25° C. for 0.4 h to obtain a mixture; mix the mixture with 50 parts by weight of deionized water, 10 Triisopropanolamine in parts by weight, ethanolamine in 30 parts by weight, hydrazine hydrate in 6 parts by weight, and sodium dodecyl sulfate in 8 parts by weight were mixed, and stirred at 25° C. for 2 hours to obtain an inhibitor composition, denoted as is C1, wherein the ammonia nitrogen content in the inhibitor composition C1 is 3.2 mg / L.

[0046] (B) The operating conditions of the alkaline washing tower include: the temperature at the top of the tower is 42° C., and the pressure at the top of the tower is 1.35 MPa.

[0047] The flow rate of the product gas at the inlet of the caustic washing tower is 90t / h, and the mass concentration of oxygen-containing compounds in the product gas at the inlet of the caustic washing tower is 100 ppm, wherein the oxyge...