CN-118724303-B - Composite corrosion and scale inhibitor, preparation method and application thereof, and geothermal Shui Huanshi scale inhibition method

Abstract

The invention relates to a geothermal water composite corrosion and scale inhibitor which comprises the following components of long-chain alkyl-dimethyl-polyethylene glycol ammonium sulfite, an organic phosphine compound, organic alkali, water-soluble inorganic zinc salt and water. The composite corrosion and scale inhibitor provided by the invention has good corrosion and scale inhibition effects in a geothermal water system in a medium-low temperature and oxygen-containing environment.

Inventors

• WANG JINHUA
• SUN FEI
• YU ZHENGQI
• ZHUO QINGQIAN

Assignees

• 中国石油化工股份有限公司
• 中石化石油化工科学研究院有限公司

Dates

Publication Date

20260505

Application Date

20230331

Claims (16)

1. 1. The composite corrosion and scale inhibitor comprises the following components of long-chain alkyl-dimethyl-polyethylene glycol ammonium sulfite, an organic phosphine compound, an organic base, a water-soluble inorganic zinc salt and water, wherein the content of the long-chain alkyl-dimethyl-polyethylene glycol ammonium sulfite is 5-15 parts by weight, the content of the organic phosphine compound is 2-10 parts by weight, the content of the organic base is 12-25 parts by weight, the content of the water-soluble inorganic zinc salt is 4-15 parts by weight, relative to 100 parts by weight of the composite corrosion and scale inhibitor, the long-chain alkyl-dimethyl-polyethylene glycol ammonium sulfite has a structure shown in the following formula, Wherein n is 2 to 6 and x is 6 to 30.
2. 2. The composite corrosion and scale inhibitor according to claim 1, further comprising one or both of a polycarboxy polymer and gluconate.
3. 3. The composite corrosion and scale inhibitor according to claim 2, wherein the content of the polycarboxy polymer is 0 to 15 parts by weight and the content of the gluconate is 0 to 15 parts by weight relative to 100 parts by weight of the composite corrosion and scale inhibitor.
4. 4. The composite corrosion and scale inhibitor according to claim 2, wherein the content of the long-chain alkyl-dimethyl-polyethylene glycol ammonium sulfite is 8-12 parts by weight, the content of the polycarboxy polymer is 2-12 parts by weight, the content of the gluconate is 2-12 parts by weight, the content of the organic phosphine compound is 4-6 parts by weight, the content of the organic base is 15-22 parts by weight, the content of the water-soluble inorganic zinc salt is 8-12 parts by weight, and the content of the water is 30-60 parts by weight, relative to 100 parts by weight of the composite corrosion and scale inhibitor.
5. 5. The composite corrosion and scale inhibitor according to claim 1 or 2, wherein n is 4 and x is 10 to 20 in the structural formula of the long-chain alkyl-dimethyl-polyethylene glycol ammonium sulfite.
6. 6. The compound corrosion and scale inhibitor according to claim 1, wherein the preparation method of the long-chain alkyl-dimethyl-polyethylene glycol ammonium sulfite comprises (1) contacting and reacting polyethylene glycol with thionyl chloride at 30-100 ℃ to obtain intermediate ethylene sulfite, and (2) contacting and reacting long-chain alkyl dimethyl tertiary amine with intermediate ethylene sulfite at 60-150 ℃ in the presence of an organic solvent to obtain long-chain alkyl-dimethyl-polyethylene glycol ammonium sulfite.
7. 7. The composite corrosion and scale inhibitor according to claim 1 or 2, wherein the organic phosphine compound is one or more selected from the group consisting of 2-hydroxyphosphonoacetic acid, 2-phosphonic acid-1, 2, 4-tricarboxylic acid butane and 1-hydroxyethyl-1, 1-biphosphoric acid.
8. 8. The composite corrosion and scale inhibitor according to claim 1 or 2, wherein the water-soluble inorganic zinc salt is selected from at least one of zinc chloride, zinc nitrate and zinc sulfate.
9. 9. The composite corrosion and scale inhibitor according to claim 1 or2, wherein the organic base is at least one selected from the group consisting of ethanolamine, diethanolamine and triethanolamine.
10. 10. The composite corrosion and scale inhibitor according to claim 2, wherein the polycarboxy polymer is selected from at least one of polyaspartic acid, polyepoxysuccinic acid, and hydrolyzed polymaleic anhydride.
11. 11. The composite corrosion and scale inhibitor according to claim 2, wherein the gluconate is at least one selected from the group consisting of sodium gluconate, potassium gluconate, sodium D-gluconate, potassium D-gluconate, zinc gluconate and manganese gluconate.
12. 12. A process for preparing a composite corrosion and scale inhibitor, which comprises mixing the components of the composite corrosion and scale inhibitor according to claim 1 or 2.
13. 13. The use of the composite corrosion and scale inhibitor according to claim 1 or 2 in the scale inhibition of geothermal Shui Huanshi.
14. 14. A method for inhibiting scale in geothermal water Shui Huanshi, which comprises adding the compound corrosion and scale inhibitor as defined in claim 1 or2 to geothermal water before the geothermal water goes out of a well.
15. 15. The method of claim 14, wherein the composite corrosion and scale inhibitor is added in an amount of 60-120mg/L based on the volume of the geothermal water.
16. 16. The method of claim 14, wherein the composite corrosion and scale inhibitor is added in an amount of 80-100mg/L based on the volume of the geothermal water.

Description

Composite corrosion and scale inhibitor, preparation method and application thereof, and geothermal Shui Huanshi scale inhibition method Technical Field The invention relates to the field of geothermal Shui Huanshi scale inhibition, in particular to a composite corrosion and scale inhibitor, a preparation method and application thereof, and a geothermal Shui Huanshi scale inhibition method. Background With rapid consumption of non-renewable resources such as petroleum, natural gas and the like, geothermal energy is attracting attention as a new energy source with a wide development prospect. Geothermal energy is a source of energy in various forms of industry and agriculture that can be used for heating, power generation, refrigeration, medical bathing, aquaculture, and the like. Geothermal fluids include geothermal water, a two-phase mixture of geothermal water and steam, geothermal steam, and the like. The geothermal fluid has very complex chemical composition, has easily corrodible components such as dissolved oxygen, chloride ions and the like, and easily scaling components such as calcium ions, silicic acid and the like, thereby causing corrosion and scaling problems of geothermal utilization equipment, pipelines, pipes and the like, and preventing efficient and economical utilization of geothermal energy. In addition to the nature of geothermal fluids, corrosion and fouling are also affected by operating conditions such as temperature, pressure, etc. and equipment materials. At present, the control method for corrosion in the geothermal water utilization process mainly comprises the following steps: The method comprises the steps of (1) selecting corrosion-resistant materials, namely selecting non-metal materials (such as PVC-U plastic pipes), and also selecting high alloy stainless steel, nickel base alloy, titanium alloy, zirconium materials and other metal materials resistant to geothermal corrosion, so as to improve the reliability of a geothermal system, (2) coating a corrosion-resistant coating on the surface of low-cost metal, so as to improve the corrosion resistance of the metal, wherein the coating mainly comprises a polyphenylene sulfide-based coating, a metal ceramic coating, a micro-nano SiO 2 coating and the like, and (3) adding chemical corrosion inhibitors, namely according to the condition of geothermal water, the related developed corrosion inhibitors mainly comprise sodium tripolyphosphate, hydrolyzed polymaleic anhydride and the like, (4) performing cathodic protection, namely performing electrochemical corrosion protection on equipment by adopting a sacrificial anode method, and (5) performing pretreatment such as washing before geothermal utilization, namely removing corrosive gas and corrosive ions in geothermal fluid by adopting pretreatment processes such as washing. At present, the methods for realizing scale inhibition in the geothermal water utilization process mainly comprise the following steps: The method comprises the steps of (1) adding a chemical scale inhibitor, (2) carrying out pretreatment descaling before geothermal utilization or recharging, (3) applying a physical field to remove scale, (4) adopting a scale inhibition coating, and (5) adopting a systematic pressurization method to inhibit scale. The problems of unstable combination of the coating and the substrate, application of chemical agents, selection of electrode materials, process operation and the like caused by different yield stress between a metal substrate such as carbon steel and the coating (especially an organic coating) are not well solved due to high price of the corrosion-resistant material and corrosion resistance of the coating, so that the problem of corrosion and scaling in the geothermal water utilization process is still not well solved, and the problem of corrosion and scaling of a geothermal system becomes a bottleneck of geothermal resource development and utilization. At present, in the field of geothermal Shui Huanshi scale inhibition, no environment-friendly corrosion and scale inhibitor aiming at medium-low temperature (30-140 ℃) and oxygen-containing environment is known. The corrosion scaling problem of the geothermal water system in the medium-low temperature and oxygen-containing environment is mainly characterized by high mineralization degree, contains dissolved oxygen and carbon dioxide with certain mass concentration, contains microorganisms such as sulfate reducing bacteria and the like, has strong corrosion scaling property and is more difficult to control. Therefore, in order to solve the above-mentioned prior art problems, it is necessary to develop an environment-friendly corrosion and scale inhibitor for a hot water system in a medium-low temperature, oxygen-containing environment. Disclosure of Invention The first aspect of the invention aims to overcome the existing defects and provide the geothermal Shui Huanshi scale inhibitor suitable for the medium-low temperatu