A polyhydroxy heterocyclic composite desulfurizer

Abstract

This invention discloses a polyhydroxy heterocyclic composite desulfurizer, which is composed of triazine, polyphosphoric acid, polycarboxylic acid, amine salt, and organic phosphoric acid mixed in a certain mass percentage. The desulfurizer prepared by this invention has excellent hydrogen sulfide absorption capacity, strong anti-salt scale inhibition performance, effectively reduces hydrogen sulfide corrosion, is stable, has low toxicity, uses readily available raw materials, is easy to industrialize, is inexpensive, simple to apply, low cost, easy to promote and use, and ensures operational safety.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of treatment and utilization of produced water in the development and production process of offshore oilfields, and particularly relates to a multi-hydroxy heterocyclic compound sulfur removal agent. BACKGROUND

[0002] Due to the special working environment of offshore oilfields, fresh water resources are limited, and a large amount of produced water or geothermal water needs to be used in the drilling and workover process. However, with the development of Bohai oilfields, the number of oil and water wells containing hydrogen sulfide due to the reasons of the reservoir itself and bacterial corrosion increases year by year, which causes high concentration of hydrogen sulfide in the produced water. This not only causes corrosion of equipment and tools, reduces the efficiency of treatment fluid, but more importantly, causes personal injury and environmental damage, bringing many problems to oilfield development and safety production.

[0003] In the Chinese patent with application number CN202111360017.4 and the invention name of "a hydrogen sulfide removal agent and its preparation method", a chelating agent containing aminomethylene diphosphonic acid and a chelate compound type hydrogen sulfide removal agent of Fe 3+ are disclosed. The molecule contains multiple phosphoric acid groups. Due to the strong chelating force of phosphoric acid groups with Fe 3+ , Fe 3+ is not easy to fall off even in a strong acidic environment, so the hydrogen sulfide removal agent has high and stable efficiency in removing hydrogen sulfide.

[0004] In the Chinese patent with application number CN202210164427.X and the invention name of "a method for removing hydrogen sulfide gas by using imidazole-based iron-based ionic liquid", an imidazole-based iron-based ionic liquid with large molar volume is used as a desulfurizer to absorb and oxidize H2S into sulfur to achieve gas desulfurization purification. Compared with traditional desulfurization methods, this desulfurization process almost does not cause loss of absorbent, has large H2S solubility and strong H2S oxidation capacity, and does not cause side reactions in the absorption process, with small secondary pollution, overcoming the problems of traditional desulfurization processes such as multiple side salts and easy pollution, and having good development prospects in the field of industrial gas purification.

[0005] In the Chinese patent with application number CN202111343576.4 and the invention name of "a hydrogen sulfide removal agent for oil and gas wells and its preparation method", a hydrogen sulfide removal agent is composed of a sulfide inhibitor, a hydrogen sulfide absorbent, a complex metal oxidant, an activator and a stabilizer. The preparation process of the hydrogen sulfide removal agent is simple and convenient. The principle of oxidation-absorption-reoxidation is adopted. After the agent is added to the corresponding high-sulfur oil pipe, casing or oil and gas pipeline, the agent fully contacts crude oil, sewage and mixed gas, so as to rapidly reduce the concentration of hydrogen sulfide and sulfur ions, and the hydrogen sulfide removal agent has the advantages of high desulfurization efficiency, stable performance, economic and environmental protection, etc.

[0006] In the Chinese patent with the application number CN201880032127.8 and the invention name "Absorbent and method for selective removal of hydrogen sulfide", an absorbent for selective removal of hydrogen sulfide from a fluid stream comprising carbon dioxide and hydrogen sulfide is disclosed. The absorbent has a reduced tendency to phase separate at temperatures within the conventional regeneration temperature range of aqueous amine mixtures and has a low volatility in aqueous solvents.

[0007] Currently, sodium hydroxide, triethanolamine, s-triazine and other single agents are commonly used as hydrogen sulfide absorbents in drilling and workover operations of Bohai oil and gas fields containing hydrogen sulfide. Cnooc uses sodium hydroxide absorption process in workover operations in Penglu oilfield, and Cnooc energy development engineering technology company uses triethanolamine + s-triazine composite sulfur removal agent, which has achieved certain effect. However, the current product has single effect, and the offshore transportation and storage of dangerous chemicals such as sodium hydroxide have high safety risk, and have no good protective effect on high salinity and high corrosive production water, resulting in short service life of equipment and increased maintenance cost. SUMMARY

[0008] The present application is proposed to solve the problems of personnel poisoning risk and equipment scaling and corrosion damage caused by ultra-high concentration hydrogen sulfide and high salinity production water in the process of offshore oil and gas field drilling and workover operations, and the purpose is to provide a multi-hydroxyl heterocyclic composite sulfur removal agent.

[0009] The present application is realized by the following technical scheme:

[0010] A multi-hydroxyl heterocyclic composite sulfur removal agent, which comprises the following components and mass percentages of each component:

[0011]

[0012] In the above technical scheme, the triazine is any one of 2-amino-4-methoxy-6-methyl-1, 3, 5-triazine, 1, 3, 5-triazine-2, 4, 6-(1H, 3H, 5H) triketone, hexahydro-1, 3, 5-tris(hydroxyethyl)-s-triazine, 2-amino-4-methyl-6-methoxy-1, 3, 5-triazine or 1, 3, 5-tris(2-hydroxyethyl)-hexahydro-s-triazine.

[0013] In the above technical scheme, the multi-phosphoric acid is any one of hydroxyethylidene diphosphonic acid HEDP, amino trimethylene phosphonic acid ATMP, ethylenediamine tetramethylene phosphonic acid EDTMPA, diethylene triamine pentamethylene phosphonic acid DTPMPA or bis 1, 6-hexylene triamine pentamethylene phosphonic acid BHMTPMPA.

[0014] In the technical scheme, the polycarboxylic acid is any one of polyaspartic acid sodium PASP, hydrolyzed polymaleic anhydride HPMA, maleic acid-acrylic acid copolymer MA / AA or epoxy succinic acid polymer PESA.

[0015] In the technical scheme, the amine salt is any one of iminodisuccinic acid tetrasodium salt IDS, ethylenediaminetetraacetic acid tetrasodium salt EDTA-4Na or diethylenetriamine pentaacetic acid pentasodium salt DTPA-5Na.

[0016] In the technical scheme, the organic phosphoric acid is any one of 2-phosphonobutane-1,2,4-tricarboxylic acid PBTCA, 2-hydroxyphosphonooxyacetic acid HPAA or polyol phosphate ester PAPE.

[0017] A preparation method of a multi-hydroxyl heterocyclic composite sulfur scavenger, specifically comprising: mixing triazine, polyphosphoric acid, polycarboxylic acid, amine salt and organic phosphoric acid in the order of mass percentage at normal temperature and pressure, and stirring uniformly to obtain the sulfur scavenger.

[0018] A use method of a multi-hydroxyl heterocyclic composite sulfur scavenger, specifically comprising: preparing the sulfur scavenger and production sewage or geothermal water in a proportion of 2.0g:100ml of mass-volume ratio, stirring uniformly to obtain a sulfur scavenger solution.

[0019] The multi-hydroxyl heterocyclic composite sulfur scavenger has the following beneficial effects:

[0020] The multi-hydroxyl heterocyclic composite sulfur scavenger and the preparation method thereof are provided, the prepared sulfur scavenger has high effective active content, and can rapidly reduce the hydrogen sulfide concentration of 50mg / L to below 0.015mg / L within 2min under the condition of small dosage; the sulfur scavenger system is acidic, can provide a large amount of free H + ions, makes S 2- , HS - ions in the working water be converted into H2S to the maximum extent, thereby being eliminated by reaction, and solves the problem that the conventional sulfur scavenger can only greatly reduce the content of gas-phase hydrogen sulfide, and the liquid phase still contains a large amount of dissolved H2S; the sulfur scavenger system components contain various chelating scale inhibitors, can effectively reduce the white gel-like polysulfide polymer precipitate generated in the absorption of hydrogen sulfide by the triazine sulfur scavenger, and can chelate Ca 2+ , Mg 2+ and other scale-forming ions, reduces the inorganic scale precipitation caused by the incompatibility of the drilling and workover fluid leakage into the reservoir; the composite high-efficiency corrosion inhibitor in the sulfur scavenger system components synergistically, can effectively avoid the scratch, under-corrosion, galvanic corrosion, under-scale friction corrosion and the like of the downhole operation equipment and tools. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a structural schematic diagram of a sulfur scavenger effect evaluation device used by the present application.

[0022] Wherein:

[0023] 1, gas collection bottle; 2, reaction bottle; 3, front-end pump suction type hydrogen sulfide detector; 4, rear-end pump suction type hydrogen sulfide detector.

[0024] For those skilled in the art, other related drawings can be obtained from the above drawings without creative labor. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical solutions of the present application, the technical solutions of the present application will be further described below in combination with the drawings of the specification and through specific embodiments.

[0026] The present application adopts a sulfur removal agent effect evaluation device as shown in Figure 1 The sulfur removal agent effect evaluation device includes front-end pump suction type hydrogen sulfide detector 3, gas collection bottle 1, reaction bottle 2 and rear-end pump suction type hydrogen sulfide detector 4 connected in sequence.

[0027] The gas collection bottle 1 is filled with ultra-high concentration hydrogen sulfide production wastewater or geothermal water, part of which is dissolved in the water phase, and part of which overflows from the reactor to simulate hydrogen sulfide generation.

[0028] The reaction bottle 2 is filled with a sulfur removal agent aqueous solution (solution salinity 20000mg / L), and 3 pieces of N80 or P110 standard steel sheets are placed at the bottom of the bottle. H2S overflowing from the gas collection bottle 1 enters the reaction bottle 2 and is absorbed by the solution to simulate hydrogen sulfide absorption.

[0029] The front-end pump suction type hydrogen sulfide detector 3 and the rear-end pump suction type hydrogen sulfide detector 4 can respectively detect the concentration of hydrogen sulfide overflowing from the gas collection bottle 1 and the concentration of hydrogen sulfide in the gas after being absorbed by the reaction bottle 2 to realize hydrogen sulfide concentration determination.

[0030] Example 1

[0031] 1. Fresh high-concentration hydrogen sulfide production wastewater samples are taken in the gas collection bottle 1 (or acid solution + sodium sulfide / ferrous sulfide can be used instead to generate hydrogen sulfide);

[0032] 2. 8.0g of a sulfur removal agent composed of 2-amino-4-methoxy-6-methyl-1,3,5-triazine, hydroxyethylidene diphosphonic acid HEDP, polyaspartic acid sodium PASP, iminodisuccinic acid tetrasodium salt IDS, and 2-phosphonobutane-1,2,4-tricarboxylic acid PBTCA in a mass percentage of 66%:5%:15%:11%:3% is weighed, 400mL of water is added to prepare a sulfur removal agent solution, which is added to the reaction bottle 2 for absorbing hydrogen sulfide gas overflowing from the gas collection bottle 1;

[0033] 3. Open the valve between the gas collection bottle 1 and the left pump suction type hydrogen sulfide detector 3, and record the overflow hydrogen sulfide concentration data A1 in the gas collection bottle 1 after 10 minutes. Figure 1 Connect the effect evaluation device of the sulfur removal agent;

[0034] 4. Open the valve between the gas collection bottle 1 and the left pump suction type hydrogen sulfide detector 3, and record the overflow hydrogen sulfide concentration data A1 in the gas collection bottle 1 after 10 minutes.

[0035] 5. Close the valve between the gas collection bottle 1 and the left pump suction type hydrogen sulfide detector 3, and open the valves between the gas collection bottle 1, the reaction bottle 2, and the right pump suction type hydrogen sulfide detector 3. Record the overflow hydrogen sulfide concentration data A2 in the reaction bottle 2 after 10 minutes.

[0036] 6. When the reading of the right pump suction type hydrogen sulfide detector is 0, close all valve doors, remove the reaction bottle 2, and place it in a constant temperature environment at 60°C for 24 hours.

[0037] 7. Take out the reaction bottle 2, and place it at room temperature until it reaches room temperature. According to the standard method of “SY / T 5673-1993 Performance Evaluation Method for Antifouling Agents for Oilfields”, measure the Ca 2+ , Mg 2+ ion content in the solution, and calculate the scale inhibition rate.

[0038] 8. Take out the steel sheet in the reaction bottle 2, process the coupon according to the standard method of “SY / T 5273-2000 Performance Evaluation Method for Corrosion Inhibitors for Oilfield Produced Water”, and calculate the uniform corrosion inhibition rate and uniform corrosion rate.

[0039] 9. The experimental results are shown in Table 1.

[0040] Table 1 Performance Evaluation Results of Sulfur Removal Agent

[0041]

[0042] Example 2

[0043] 1. Take a fresh high-concentration hydrogen sulfide production wastewater sample from the gas collection bottle 1 (or use acid solution + sodium sulfide / ferrous sulfide to replace it, and generate hydrogen sulfide by reaction);

[0044] 2. Take 8.0g of a sulfur removal agent composed of hexahydro-1,3,5-tris(hydroxyethyl)-s-triazine, amino-trimethylene phosphonic acid ATMP, polyhydrolyzed poly-maleic anhydride HPMA, ethylenediaminetetraacetic acid tetrasodium EDTA-4Na, and 2-hydroxyphosphonoacetic acid HPAA in a mass percentage of 62%:7%:14%:12%:5%, add water 400mL to prepare a sulfur removal agent solution, and add it to the reaction bottle 2 for absorbing the overflow hydrogen sulfide gas in the gas collection bottle 1;

[0045] 3. Open the valve between the gas collection bottle 1 and the left pump suction type hydrogen sulfide detector 3, and record the overflow hydrogen sulfide concentration data A1 in the gas collection bottle 1 after 10 minutes. Figure 1 Connect the effect evaluation device of the sulfur removal agent;

[0046] 4. Open the valve between the gas collection bottle 1 and the left pump suction hydrogen sulfide detector 3, and record the overflow hydrogen sulfide concentration data A1 in the gas collection bottle 1 for 10 minutes;

[0047] 5. Close the valve between the gas collection bottle 1 and the left pump suction hydrogen sulfide detector 3, and open the valves between the gas collection bottle 1, the reaction bottle 2, and the right pump suction hydrogen sulfide detector 3. Record the overflow hydrogen sulfide concentration data A2 in the reaction bottle 2 for 10 minutes;

[0048] 6. When the right pump suction hydrogen sulfide detector reads 0, close all valve doors, remove the reaction bottle 2, and place it in a constant temperature environment at 60°C for 24 hours;

[0049] 7. Take out the reaction bottle 2, and place it in a room temperature environment until it reaches room temperature. Measure the Ca 2+ , Mg 2+ ion content in the solution according to the standard method in “SY / T 5673-1993 Performance Evaluation Method for Antifouling Agents for Oilfields”, and calculate the scale inhibition rate.

[0050] 8. Take out the steel sheet from the reaction bottle 2, process the coupon according to the standard method in “SY / T 5273-2000 Performance Evaluation Method for Corrosion Inhibitors for Oilfield Produced Water”, and calculate the uniform corrosion inhibition rate and uniform corrosion rate.

[0051] 9. The experimental results are shown in Table 2;

[0052] Table 2 Performance Evaluation Results of Sulfur Removal Agents

[0053]

[0054]

[0055] Example 3

[0056] 1. Take a fresh high-concentration hydrogen sulfide production wastewater sample from the gas collection bottle 1 (or use acid solution + sodium sulfide / ferrous sulfide to replace it, and generate hydrogen sulfide through reaction);

[0057] 2. Take 8.0g of a sulfur removal agent composed of 2-amino-4-methyl-6-methoxy-1,3,5-triazine, ethylenediaminetetramethylene phosphonic acid EDTMPA, maleic acid-acrylic acid copolymer MA / AA, ethylenetriamine pentaacetic acid pentasodium salt DTPA-5Na, and polyol phosphate PAPE in a mass percentage of 70%:6%:10%:11%:3%, add water 400mL to prepare a sulfur removal agent solution, and add it to the reaction bottle 2 for absorbing the overflow hydrogen sulfide gas in the gas collection bottle 1;

[0058] 3. Follow the instructions in the attached Figure 1The good effect of the desulfurizer is evaluated by connecting the device;

[0059] 4. Open the valve for connecting the gas collecting bottle 1 with the left pump suction type hydrogen sulfide detector 3, and record the overflow hydrogen sulfide concentration data A1 in the gas collecting bottle 1 after 10 minutes;

[0060] 5. Close the valve for connecting the gas collecting bottle 1 with the left pump suction type hydrogen sulfide detector 3, open the valves for connecting the gas collecting bottle 1, the reaction bottle 2 and the right pump suction type hydrogen sulfide detector 3, and record the overflow hydrogen sulfide concentration data A2 in the reaction bottle 2 after 10 minutes;

[0061] 6. When the reading of the right pump suction type hydrogen sulfide detector is 0, close all the valves, take out the reaction bottle 2, and keep it at 60℃ for 24 hours;

[0062] 7. Take out the reaction bottle 2, keep it at room temperature until it reaches room temperature, and measure the Ca 2+ , Mg 2+ ion content in the solution according to the standard method in SY / T 5673-1993 Performance Evaluation Method of Anti-scale Agent for Oil Field, and calculate the scale inhibition rate.

[0063] 8. Take out the steel sheet in the reaction bottle 2, process the hanging sheet according to the standard method in SY / T 5273-2000 Performance Evaluation Method of Corrosion Inhibitor for Oil Field Produced Water, and calculate the uniform corrosion inhibition rate and the uniform corrosion rate.

[0064] 9. The experimental results are shown in Table 3;

[0065] Table 3 Performance Evaluation Results of Desulfurizer

[0066]

[0067] Example 4

[0068] 1. Take fresh high-concentration hydrogen sulfide production wastewater sample in the gas collecting bottle 1 (or acid liquid + sodium sulfide / ferrous sulfide can be used instead to generate hydrogen sulfide);

[0069] 2. Take 8.0g of desulfurizer composed of 1,3,5-tris(2-hydroxyethyl)-hexahydro-sym-triazine, diethylene triamine penta(methylene phosphonic acid) DTPMPA, epoxy succinic acid polymer PESA, imino disuccinic acid tetrasodium salt IDS, and 2-phosphonobutane-1,2,4-tricarboxylic acid PBTCA in a mass percentage of 68%:8%:11%:9%:4%, add water 400mL to prepare a desulfurizer solution, and add it to the reaction bottle 2 for absorbing the overflow hydrogen sulfide gas in the gas collecting bottle 1;

[0070] 3. Connect the device according to the attached Figure 1 The good effect of the desulfurizer is evaluated by connecting the device;

[0071] 4. Open the valve between the gas collection bottle 1 and the left pump suction type hydrogen sulfide detector 3, and record the overflow hydrogen sulfide concentration data A1 in the gas collection bottle 1 for 10 minutes;

[0072] 5. Close the valve between the gas collection bottle 1 and the left pump suction type hydrogen sulfide detector 3, and open the valves between the gas collection bottle 1, the reaction bottle 2, and the right pump suction type hydrogen sulfide detector 3. Record the overflow hydrogen sulfide concentration data A2 in the reaction bottle 2 for 10 minutes;

[0073] 6. When the reading of the right pump suction type hydrogen sulfide detector is 0, close all valve doors, remove the reaction bottle 2, and place it in a constant temperature environment at 60°C for 24 hours;

[0074] 7. Take out the reaction bottle 2, and place it in a room temperature environment until it reaches room temperature. According to the standard method of “SY / T 5673-1993 Performance Evaluation Method for Antifouling Agents for Oilfields”, measure the Ca 2+ , Mg 2+ ion content in the solution, and calculate the scale inhibition rate.

[0075] 8. Take out the steel sheet in the reaction bottle 2, process the coupon according to the standard method of “SY / T 5273-2000 Performance Evaluation Method for Corrosion Inhibitors for Oilfield Produced Water”, and calculate the uniform corrosion inhibition rate and uniform corrosion rate.

[0076] 9. The experimental results are shown in Table 4;

[0077] Table 4 Performance Evaluation Results of Sulfur Removal Agent

[0078]

[0079] Example 5

[0080] 1. Take a fresh high-concentration hydrogen sulfide production wastewater sample in the gas collection bottle 1 (or use acid solution + sodium sulfide / ferrous sulfide to replace it, and generate hydrogen sulfide by reaction);

[0081] 2. Take 8.0g of sulfur removal agent composed of 1,3,5-triazine-2,4,6-(1H,3H,5H) triketone, bis 1,6-hexylene triamine pentamethylene phosphonic acid BHMTPMPA, hydrolyzed poly maleic anhydride HPMA, iminodisuccinic acid tetrasodium salt IDS, 2-phosphonic butane-1,2,4-tricarboxylic acid PBTCA, and water 400mL, with a mass percentage of 67%:5%:13%:10%:5%, to prepare a sulfur removal agent solution, and add it to the reaction bottle 2 for absorbing the overflow hydrogen sulfide gas in the gas collection bottle 1;

[0082] 3. Connect the sulfur removal agent effect evaluation device according to the attached Figure 1

[0083] ​4. Open the valve for connecting the gas collecting bottle 1 with the left side pump suction type hydrogen sulfide detector 3, and record the overflow hydrogen sulfide concentration data A1 in the gas collecting bottle after 10 minutes;

[0084] 5. Close the valve for connecting the gas collecting bottle 1 with the left side pump suction type hydrogen sulfide detector 3, and open the valves for connecting the gas collecting bottle 1, the reaction bottle 2 and the right side pump suction type hydrogen sulfide detector 3, and record the overflow hydrogen sulfide concentration data A2 in the reaction bottle 2 after 10 minutes;

[0085] 6. When the reading of the right side pump suction type hydrogen sulfide detector is 0, close all the valves, and take out the reaction bottle 2, and keep it at 60℃ for 24 hours;

[0086] 7. Take out the reaction bottle 2, and keep it at room temperature until it reaches room temperature, and according to the standard method of SY / T 5673-1993 Performance Evaluation Method of Anti-scaling Agent for Oil Field, measure the Ca 2+ , Mg 2+ ion content in the solution, and calculate the scale inhibition rate.

[0087] 8. Take out the steel sheet in the reaction bottle 2, and process the hanging sheet according to the standard method of SY / T 5273-2000 Performance Evaluation Method of Corrosion Inhibitor for Oil Field Produced Water, and calculate the uniform corrosion inhibition rate and the uniform corrosion rate.

[0088] 9. The experimental results are shown in Table 5;

[0089] Table 5 Performance Evaluation Results of Sulfur Removal Agent

[0090]

[0091] The sulfur removal agent can quickly absorb the hydrogen sulfide gas component in the produced water for operation in the drilling and workover process of the ultra-high hydrogen sulfide oil and gas field, and can quickly reduce the hydrogen sulfide concentration from 50mg / L to below 0.015mg / L within 2 minutes, so as to prevent the overflow and dispersion of high-concentration hydrogen sulfide gas, and solve the problem of hydrogen sulfide personnel injury in the drilling and workover process. Meanwhile, the scaling caused by the incompatibility of water quality and other potential factors in the produced water with high salinity in the operation process and the equipment corrosion caused by hydrogen sulfide can be solved.

[0092] The applicant declares that the above description is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and those skilled in the art should understand that any changes or replacements within the technical scope disclosed by the present application can be easily thought by any person skilled in the art, and all fall within the protection scope and disclosure scope of the present application.

Claims

1. A multi-hydroxy heterocyclic complex sulfur scavenger, characterized by: The sulfur removal agent comprises the following components and mass percentages of each component: 62-70% triazine; 5-8% polybasic phosphoric acid; 10-15% polycarboxylic acid; 7-12% amine salt; 3-5% organic phosphoric acid; The polybasic phosphoric acid is any one of hydroxyethylidene diphosphonic acid, amino trimethylene phosphonic acid, ethylenediamine tetramethylene phosphonic acid, diethylene triamine pentamethylene phosphonic acid or bis 1,6-hexylene triamine pentamethylene phosphonic acid; The organic phosphoric acid is any one of 2-phosphonobutane-1,2,4-tricarboxylic acid, 2-hydroxyphosphonoacetic acid or polyol phosphoric acid ester; The triazine is any one of 2-amino-4-methoxy-6-methyl-1,3,5-triazine, 1,3,5-triazine-2,4,6-(1H,3H,5H) triketone, hexahydro-1,3,5-tris(hydroxyethyl)-s-triazine, 2-amino-4-methyl-6-methoxy-1,3,5-triazine or 1,3,5-tris(2-hydroxyethyl)-hexahydro-s-triazine; The polycarboxylic acid is any one of sodium polyaspartate, hydrolyzed polymaleic anhydride, maleic acid-acrylic acid copolymer or epoxy succinic acid polymer; The amine salt is any one of iminodisuccinic acid tetrasodium salt, ethylenediaminetetraacetic acid tetrasodium or diethylenetriamine pentaacetic acid pentasodium salt.

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