Sulfur-containing circulating cooling water scale and corrosion inhibitor and use method thereof

Abstract

The invention relates to a sulfur-containing circulating cooling water scale and corrosion inhibitor and a use method thereof, and the sulfur-containing circulating cooling water scale and corrosion inhibitor comprises the following components in percentage by mass: 1-6% of inorganic phosphoric acid or phosphate; 3-20% of polybasic organic acid; 8-15% of hydrolytic polymaleic anhydride; in terms of zinc ions, 1-10% of zinc salt; 12-20% of an acrylic acid homopolymer or copolymer; 0-20% of sodium gluconate, 0-10% of copper slow and 0-10% of water-soluble imidazoline, and the contents of the sodium gluconate, the copper slow and the water-soluble imidazoline are not 0 at the same time; and the balance of water. The precipitation film corrosion inhibitor composed of inorganic phosphorus, multi-element organic acid, polymer and zinc salt and the adsorption film corrosion inhibitor composed of sodium gluconate, copper sulfate, water-soluble imidazoline and the like are adopted to jointly enhance the corrosion inhibition effect on carbon steel in a sulfide-containing circulating water system, and the two types of corrosion inhibitors are compounded to have an obvious synergistic effect; and corrosion of materials such as carbon steel in sulfide high-chloride-ion circulating water can be effectively inhibited.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of corrosion inhibitors, in particular to a sulfur-containing circulating cooling water scale and corrosion inhibitor and a use method thereof. BACKGROUND

[0002] In the process of coal chemical industry or petroleum refining, some sulfur compounds will be produced, including organic sulfides and inorganic sulfides, wherein the inorganic sulfur includes elemental sulfur, hydrogen sulfide, sodium sulfide, etc., and the organic sulfur includes mercaptans, sulfides, disulfides, polysulfides and thiophenes. In the open intercooling circulating water system, with the micro-leakage of heat exchange medium or through the measures of washing air containing hydrogen sulfide in the cooling tower, a certain amount of sulfides often exist in the circulating water, thereby affecting the stable operation of the circulating water. Tang Anzhong (2009) reported that inorganic sulfur (hydrogen sulfide) is the main cause of serious corrosion of carbon steel equipment. The corrosion hazards of hydrogen sulfide mainly manifest in the pitting corrosion (point corrosion pits), corrosion cracking (including hydrogen blistering, hydrogen-induced cracking, stress corrosion), and the corrosion appearance presents size varying concave pits, some of which are point corrosion pits and some of which are ulcer-like corrosion pits, until perforation leakage. On the one hand, sulfides consume oxidizing bactericides, making the bactericides ineffective or increasing the dosage of the bactericides; on the other hand, sulfur ions directly react with zinc ions to form precipitates, resulting in the failure of zinc ion corrosion inhibition, which will indirectly or directly lead to the intensification of system carbon steel corrosion. Therefore, inhibiting or eliminating the corrosion of sulfides on carbon steel is one of the key points of the field operation and maintenance of the sulfur-containing circulating water in coal chemical industry or petroleum refining.

[0003] Patent CN1341564A discloses a method for treating sulfur-containing circulating cooling water, i.e. adding a leakage S 2- 2-15 times of oxidizing biocide with a weight concentration of 2-15 times of oxidizing biocide, including chlorine, sodium dichloroisocyanurate, trichloroisocyanuric acid, chlorine dioxide, sodium hypochlorite, hypobromous acid and its salt, bromochlorodimethylhydantoin, active bromine, etc. The principle of the method is to oxidize sulfur ions into elemental sulfur or sulfate. However, in the actual operation process, it is found that there is a serious hysteresis effect from the detection of sulfides in the circulating water to the addition of chlorine / bromine oxidizing agent to the system. At this time, the carbon steel surface has already existed relatively serious corrosion phenomenon, or even if the continuous addition of oxidizing bactericide is adopted, the bactericide needs to be maintained at a high concentration, and when the sudden corrosion leakage increases, the corrosion of sulfides on carbon steel cannot be effectively inhibited. The above two phenomena often occur in coal chemical industry or refining enterprises, especially for the enterprises that are waste water zero discharge units, the recycled water is generally used as the make-up water of the circulating water, and the make-up water generally has high chlorine ion, and the sulfide leakage often leads to serious intensification of system corrosion.

[0004] According to the field operation experience and literature reports, the oxidizing bactericide has the defect of aggravating the corrosion of carbon steel. Therefore, when the oxidizing bactericide is added to the circulating water, a certain residual chlorine value needs to be controlled. Generally, after the impact addition of the oxidizing bactericide for 2 h, the residual chlorine value in the circulating water is maintained at 0.5-1.0 mg / L or continuously added to maintain the residual chlorine value at 0.1-0.5 mg / L (referring to GB / T 50050-2017). When there is sulfide leakage, especially long-term intermittent micro-leakage, if a sulfide detection system is not established, it is generally difficult to find that the corrosion rate of carbon steel exceeds the standard due to the presence of sulfide in the circulating water; even if the sulfide content is detected every day, from the detection result to the impact addition of the oxidizing bactericide or the increase of the continuous addition amount, it belongs to a passive treatment, and at this time, it may be found that the corrosion of the carbon steel material in the system has been caused, and the corrosion is often more serious. SUMMARY

[0005] The purpose of the present application is to overcome the above technical deficiencies, provide a kind of containing sulfur circulating cooling water scale and corrosion inhibitor and its use method, solve the technical problems of serious corrosion of carbon steel and other equipment in high-chlorine circulating water containing sulfur in the prior art and passive treatment.

[0006] To achieve the above technical purpose, the technical solution provided by the present application is: In a first aspect, the present application provides a kind of containing sulfur circulating cooling water scale and corrosion inhibitor, by mass fraction, including inorganic phosphoric acid or phosphate 1-6%;Multiple organic acids 3-20%;Hydrolyzed polymaleic anhydride 8-15%;Zinc salt 1-10% by zinc ion;Acrylic acid homopolymer or copolymer 12-20%;Sodium gluconate 0-20%, copper buffer 0-10%, water-soluble imidazoline 0-10%, and the content of sodium gluconate, copper buffer and water-soluble imidazoline is not simultaneously 0;The rest is water.

[0007] In a second aspect, the present application provides a kind of containing sulfur circulating cooling water scale and corrosion inhibitor and its use method, including the following steps: scale and corrosion inhibitor is added to circulating cooling water at a concentration of 100-300 mg / L for operation.

[0008] Compared with the prior art, the beneficial effects of the present application include: The present application adopts the precipitated film corrosion inhibitor composed of inorganic phosphorus + multiple organic acids + polymer + zinc salt, and the adsorbed film corrosion inhibitor composed of sodium gluconate, copper buffer, water-soluble imidazoline and the like to jointly enhance the corrosion inhibition effect on carbon steel materials in the circulating water system containing sulfide, and the two types of corrosion inhibitors have obvious synergistic effect, can effectively inhibit the corrosion of carbon steel and other materials in the high-chlorine circulating water containing sulfide, and the corrosion rate is less than 0.075 mm / a, which meets the requirements of GB / T 50050-2017. DETAILED DESCRIPTION

[0009] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application.

[0010] In view of the defects in the prior art that carbon steel is severely corroded in high-chlorine sulfur-containing circulating water and the treatment is passive, the present application provides a sulfur-containing circulating cooling water scale and corrosion inhibitor and a use method thereof. The scale and corrosion inhibitor is a composite scale and corrosion inhibitor, which is mainly composed of inorganic phosphoric acid or phosphate, zinc salt, multi-element organic phosphonic acid (carboxylic acid), hydrolyzed polymaleic anhydride (HPMA), acrylic acid homopolymer or copolymer, sodium gluconate, copper buffer, water-soluble imidazoline, etc. The dosage of the scale and corrosion inhibitor is between 100-300 mg / L when used, and the scale and corrosion inhibitor can effectively inhibit the corrosion of carbon steel, stainless steel and copper materials caused by sulfides when added into the circulating water system.

[0011] In the first aspect, the present application provides a sulfur-containing circulating cooling water scale and corrosion inhibitor, which comprises, by mass percentage, 1-6% of inorganic phosphoric acid or phosphate; 3-20% of multi-element organic acid; 8-15% of hydrolyzed polymaleic anhydride; 1-10% of zinc salt in terms of zinc ion; 12-20% of acrylic acid homopolymer or copolymer; 0-20% of sodium gluconate, 0-10% of copper buffer, and 0-10% of water-soluble imidazoline, and the contents of sodium gluconate, copper buffer and water-soluble imidazoline are not simultaneously 0; and the rest is water.

[0012] Preferably, the scale and corrosion inhibitor comprises, by mass percentage, 2-6% of inorganic phosphoric acid or phosphate; 5-20% of multi-element organic acid; 10-15% of hydrolyzed polymaleic anhydride; 2-4% of zinc salt in terms of zinc ion; 15-20% of acrylic acid homopolymer or copolymer; 15-20% of sodium gluconate; 5-10% of copper buffer; 5-10% of water-soluble imidazoline; and the rest is water.

[0013] The composite scale and corrosion inhibitor of the present application comprehensively considers the scale and corrosion inhibition performance requirements of the circulating water system. The organic phosphonic acid (carboxylic acid), hydrolyzed polymaleic anhydride, acrylic acid homopolymer or copolymer used in the present application has scale inhibition effect and can form a composite corrosion inhibitor with zinc salt and inorganic phosphorus, and has typical critical concentration effect (i.e. when the concentration of the agent is lower than a certain concentration, the effect is poor; when the concentration of the agent is equal to the certain concentration, the effect is very obvious; when the concentration of the agent continues to increase, the effect of the agent continues to increase, or maintains the critical concentration effect); the inorganic phosphoric acid or phosphate, zinc salt, and the organic phosphonic acid (carboxylic acid) and the hydrolyzed polymaleic anhydride (HPMA), acrylic acid homopolymer or copolymer form a typical deposition type corrosion inhibition film, and the above monomers also have typical critical concentration effect; the copper buffer has very significant effect on copper material corrosion inhibition, and also has corrosion inhibition effect on carbon steel material; sodium gluconate and water-soluble imidazoline form an adsorption film on carbon steel to enhance the corrosion inhibition effect on carbon steel, and also have typical critical concentration effect. The present application achieves excellent scale and corrosion inhibition effect through the cooperation of various components.

[0014] Preferably, the inorganic phosphoric acid or phosphate includes one or more of phosphoric acid solution, sodium tripolyphosphate and sodium hexametaphosphate.

[0015] Further preferably, the mass concentration of the phosphoric acid solution is 75-85%.

[0016] Preferably, the polybasic organic acid includes polybasic organic phosphonic acid or polybasic organic phosphonocarboxylic acid.

[0017] Further preferably, the polybasic organic acid includes one or more of amino-tris-methylene phosphonic acid (ATMP), hydroxy-ethylidene diphosphonic acid (HEDP), 2-phosphonooxy-1,2,4-tricarboxy butane (PBTCA), diethylene triamine penta-methylene phosphonic acid (DTPMP), 2-hydroxy phosphono acetic acid (HPAA), polyamino polyether methylene phosphonic acid (PAPEMP, which meets the requirements of GBT 27812-2011).

[0018] Preferably, the zinc salt includes zinc sulfate.

[0019] Preferably, the acrylic acid homopolymer or copolymer includes one or more of polyacrylic acid (PAA) and acrylic acid-2-methyl-2-acrylamidopropyl sulfonic acid copolymer (AA-AMPS).

[0020] Preferably, the copper buffer includes: 25-35wt% of an aqueous solution of methyl benzotriazole (TTA) or 25-35wt% of an aqueous solution of benzotriazole (BTA) with pH>12. The amount of the copper buffer in the present application is calculated based on BTA.

[0021] Preferably, the water-soluble imidazoline includes a double alkyl imidazoline quaternary ammonium salt.

[0022] It can be understood that the double alkyl imidazoline quaternary ammonium salt of the present application preferably adopts sodium salt, such as adopting benzoic acid, diethylene triamine, sodium chloroacetate as raw materials, and obtaining imidazoline quaternary ammonium salt compound through conventional imidazoline synthesis reaction.

[0023] In a second aspect, the present application provides a use method of a scale and corrosion inhibitor for a circulating cooling water containing sulfide, comprising the following steps: adding the scale and corrosion inhibitor into the circulating cooling water at a dosage concentration of 100-300 mg / L for operation.

[0024] Preferably, when the sulfide content in the circulating cooling water is <2.0 mg / L, the dosage concentration of the scale and corrosion inhibitor is 100-200 mg / L; when the sulfide content in the circulating cooling water is ≥2.0 mg / L, the dosage concentration of the scale and corrosion inhibitor is 200-300 mg / L.

[0025] The main action mechanism and advantages of the present application are: (1) The present application adopts a precipitated film corrosion inhibitor composed of inorganic phosphorus + organic phosphine + polymer + zinc, and an adsorbed film corrosion inhibitor composed of sodium gluconate, copper buffer, water-soluble imidazoline, etc. to strengthen the corrosion inhibition effect on carbon steel materials in the circulating water system containing sulfide; the combination of the two types of corrosion inhibitors has obvious synergistic effect, which can effectively inhibit the corrosion of carbon steel in the circulating water containing sulfide and high chloride ions; (2) Compared with the addition of oxidizing bactericide (passive treatment), the present application is a sulfide-resistant active defense type scale and corrosion inhibitor, which can form a deposited film and an adsorbed film to actively prevent the corrosion of carbon steel caused by sulfide of a certain concentration, and can also prevent the corrosion of carbon steel caused by the leakage of sulfide in time.

[0026] The present application will be further described in detail below in combination with specific examples. It should be emphasized that the following description is only exemplary and is not intended to limit the scope of the present application and its applications. In order to avoid redundancy, the raw materials used are described as follows: AA-AMPS (the physical and chemical indicators meet the requirements of HG / T 3642-2016), hydrolyzed polymaleic anhydride (the physical and chemical indicators meet the requirements of GB / T 10535-2014), copper buffer (30% aqueous solution of benzotriazole, pH 13), and water-soluble imidazoline is double alkyl imidazoline quaternary ammonium sodium salt.

[0027] Among them, the sulfide content in the circulating water is detected by HJ1226-2021 "Water Quality-Determination of Sulfide-Methylene Blue Spectrophotometric Method", and is calculated based on sulfide ion.

[0028] Example 1 In this example, 20# carbon steel is used for rotating hanging piece corrosion test, which is carried out according to GB / T18175-2014, the test temperature is 50.0℃, the rotating speed is 75 revolutions / min, and the running time is 72h.

[0029] The test uses coal chemical circulating water: pH value 8.8, conductivity 3500 μs / cm, chloride ion 600 mg / L, calcium hardness (calculated as calcium carbonate) 300 mg / L, total alkalinity (calculated as calcium carbonate) 600 mg / L, total iron 0.9 mg / L, ammonia nitrogen 0.6 mg / L, COD 60 mg / L, sulfide (sulfide ion) content 1.5-2.5 mg / L.

[0030] The scale and corrosion inhibitor formula is: 85% phosphoric acid 2%, HEDP 5%, HPMA 10%, zinc sulfate heptahydrate (zinc ion) 2%, AA-AMPS 15%, sodium gluconate 15%, BTA 5%, water-soluble imidazoline 5%, and the rest is water.

[0031] The scale and corrosion inhibitor is added to the coal chemical circulating water, and the concentration and corrosion rate results are shown in Table 1 below.

[0032] Table 1 Corrosion rate results of coal chemical circulating water in Example 1

[0033] As can be seen from Table 1, the corrosion rate of 20# carbon steel in this example is less than 0.075 mm / a, which meets the requirements of GB / T 50050-2017.

[0034] At the same time, the scale and corrosion inhibitor also has significant scale inhibition performance. According to GB / T 16632-2019 test, when the dosage concentration is ≥100 mg / L, the static scale inhibition rate is ≥95%; in the field application, there is no obvious scaling on the heat exchanger tube for more than 1 year, and there is no obvious scaling in the cooling tower filler, and the scale inhibition effect is excellent.

[0035] Example 2 The difference from Example 1 is only that the sodium gluconate is removed from the scale and corrosion inhibitor, i.e. the scale and corrosion inhibitor formula is as follows: 85% phosphoric acid 2%, HEDP 5%, HPMA 10%, zinc sulfate heptahydrate 10%, AA-AMPS 15%, BTA 5%, water-soluble imidazoline 5%, and the rest is water; other steps and conditions (including test method and test water quality) are the same as Example 1. The concentration and corrosion rate results are shown in Table 2 below.

[0036] Table 2 Corrosion rate results of coal chemical circulating water in Example 2

[0037] From the results of Table 2, it can be seen that when the sulfide content is low (less than 2 mg / L), the addition concentration of the scale and corrosion inhibitor in this embodiment is 100-300 mg / L, and the corrosion rate of 20# carbon steel is less than 0.075 mm / a, which meets the requirements of GB / T 50050-2017.

[0038] Example 3 The difference from Example 1 is only that the water-soluble imidazoline is removed from the scale and corrosion inhibitor, i.e. the scale and corrosion inhibitor formula is as follows: 85% phosphoric acid 2%, HEDP 5%, HPMA 10%, zinc sulfate heptahydrate 10%, AA-AMPS 15%, BTA 5%, sodium gluconate 15%, and the rest is water; other steps and conditions (including test method and test water quality) are the same as Example 1. The added concentration and corrosion rate results are shown in Table 3.

[0039] Table 3 Corrosion rate results of coal chemical circulating water in Example 3

[0040] From the results of Table 3, it can be seen that when the sulfide content is low (less than 2 mg / L), the addition concentration of the scale and corrosion inhibitor in this embodiment is 100-300 mg / L, and the corrosion rate of 20# carbon steel is less than 0.075 mm / a, which meets the requirements of GB / T 50050-2017.

[0041] Example 4 The difference from Example 1 is only that BTA is removed from the scale and corrosion inhibitor, i.e. the scale and corrosion inhibitor formula is as follows: 85% phosphoric acid 2%, HEDP 5%, HPMA 10%, zinc sulfate heptahydrate 10%, AA-AMPS 15%, sodium gluconate 15%, water-soluble imidazoline 5%, and the rest is water; other steps and conditions (including test method and test water quality) are the same as Example 1. The added concentration and corrosion rate results are shown in Table 4.

[0042] Table 4 Corrosion rate results of coal chemical circulating water in Example 4

[0043] From the results of Table 4, it can be seen that when the sulfide content is low (less than 2 mg / L), the addition concentration of the scale and corrosion inhibitor in this embodiment is 100-300 mg / L, and the corrosion rate of 20# carbon steel is less than 0.075 mm / a, which meets the requirements of GB / T 50050-2017.

[0044] Example 5 The difference from Example 1 is only that BTA and water-soluble imidazoline are removed from the scale and corrosion inhibitor, i.e. the scale and corrosion inhibitor formula is as follows: 85% phosphoric acid 2%, HEDP 5%, HPMA 10%, zinc sulfate heptahydrate 10%, AA-AMPS 15%, sodium gluconate 15%, and the rest is water; other steps and conditions (including test method and test water quality) are the same as Example 1. The added concentration and corrosion rate results are shown in Table 5 below.

[0045] Table 5 Coal chemical circulating water corrosion rate results of Example 5

[0046] From the results in Table 5, it can be seen that after removing BTA and water-soluble imidazoline from the scale and corrosion inhibitor in this example, when the sulfide content is low (below 1.5 mg / L), the scale and corrosion inhibitor dosage concentration is 100-200 mg / L, which can make the corrosion rate of 20# carbon steel less than 0.075 mm / a, meeting the requirements of GB / T 50050-2017.

[0047] Example 6 The difference from Example 1 is only that sodium gluconate and water-soluble imidazoline are removed from the scale and corrosion inhibitor, i.e. the scale and corrosion inhibitor formula is as follows: 85% phosphoric acid 2%, HEDP 5%, HPMA 10%, zinc sulfate heptahydrate 10%, AA-AMPS 15%, BTA 5%, and the rest is water; other steps and conditions (including test method and test water quality) are the same as Example 1. The added concentration and corrosion rate results are shown in Table 6 below.

[0048] Table 6 Coal chemical circulating water corrosion rate results of Example 6

[0049] From the results in Table 6, it can be seen that after removing sodium gluconate and water-soluble imidazoline from the scale and corrosion inhibitor in this example, when the sulfide content is low (below 1.5 mg / L), the scale and corrosion inhibitor dosage concentration is 100-200 mg / L, which can make the corrosion rate of 20# carbon steel less than 0.075 mm / a, meeting the requirements of GB / T 50050-2017.

[0050] Example 7 The difference from Example 1 is only that sodium gluconate and BTA are removed from the scale and corrosion inhibitor, i.e. the scale and corrosion inhibitor formula is as follows: 85% phosphoric acid 2%, HEDP 5%, HPMA 10%, zinc sulfate heptahydrate 10%, AA-AMPS 15%, water-soluble imidazoline 5%, and the rest is water; other steps and conditions (including test method and test water quality) are the same as Example 1. The added concentration and corrosion rate results are shown in Table 7 below.

[0051] Table 7 Coal chemical circulating water corrosion rate results of Example 7

[0052] As can be seen from the results of Table 7, after removing sodium gluconate and BTA from the scale and corrosion inhibitor of the present embodiment, when the sulfide content is relatively low (1.5 mg / L or less), the scale and corrosion inhibitor can be added at a concentration of 200 mg / L to make the corrosion rate of 20# carbon steel less than 0.075 mm / a, meeting the requirements of GB / T 50050-2017.

[0053] Comparative Example 1 The difference from Example 1 is only that sodium gluconate, BTA and water-soluble imidazoline are removed from the scale and corrosion inhibitor, i.e. the scale and corrosion inhibitor formulation is as follows: 85% phosphoric acid 2%, HEDP 5%, HPMA 10%, zinc sulfate heptahydrate 10%, AA-AMPS 15%, and the rest is water; other steps and conditions (including test method and test water quality) are the same as Example 1. The added concentration and corrosion rate results are shown in Table 8 below.

[0054] Table 8 Coal chemical circulating water corrosion rate results of Comparative Example 1

[0055] As can be seen from the results of Table 8, the corrosion rate of 20# carbon steel in Comparative Example 1 is much greater than 0.075 mm / a, which indicates that sodium gluconate, BTA and water-soluble imidazoline have a significant synergistic effect on the corrosion inhibition of carbon steel in coal chemical circulating water with high chlorine and high sulfur content.

[0056] In summary, the present application uses a precipitated film corrosion inhibitor composed of inorganic phosphorus + organic phosphine + polymer + zinc, and an adsorbed film corrosion inhibitor composed of sodium gluconate, copper buffer, water-soluble imidazoline, etc. to jointly enhance the corrosion inhibition of carbon steel materials in a circulating water system containing sulfides. The combination of the two types of corrosion inhibitors has a significant synergistic effect, which can effectively inhibit the corrosion of carbon steel in circulating water with high sulfides (sulfide content up to 2.5 mg / L) and high chlorine ions, with a corrosion rate of less than 0.075 mm / a, meeting the requirements of GB / T 50050-2017.

[0057] The specific embodiments of the application described above do not constitute a limitation on the scope of protection of the application. Any various other corresponding changes and modifications made in accordance with the technical concept of the application should be included within the scope of protection of the claims of the application.

Claims

1. A scale and corrosion inhibitor for a sulfur-containing recirculating cooling water, characterized by, 1-6% of inorganic phosphoric acid or phosphate by mass; 3-20% of polybasic organic acid; 8-15% of hydrolyzed polymaleic anhydride; 1-10% of zinc salt in terms of zinc ion; 12-20% of acrylic acid homopolymer or copolymer; 0-20% of sodium gluconate, 0-10% of copper buffer, 0-10% of water-soluble imidazoline, and the content of sodium gluconate, copper buffer and water-soluble imidazoline is not zero at the same time; and the rest is water.

2. The sulphur-containing cyclic cooling water scale and corrosion inhibitor according to claim 1, characterized in that, 2-6% of inorganic phosphoric acid or phosphate by mass; 5-20% of polybasic organic acid; 10-15% of hydrolyzed polymaleic anhydride; 2-4% of zinc salt in terms of zinc ion; 15-20% of acrylic acid homopolymer or copolymer; 15-20% of sodium gluconate; 5-10% of copper buffer; 5-10% of water-soluble imidazoline; and the rest is water.

3. The sulphur-containing cyclic cooling water scale and corrosion inhibitor according to claim 1, characterized in that, The inorganic phosphoric acid or phosphate includes one or more of phosphoric acid solution, sodium tripolyphosphate and sodium hexametaphosphate. The mass concentration of the phosphoric acid solution is 75-85%.

4. The sulphur-containing cyclic cooling water scale and corrosion inhibitor of claim 1, wherein, The polybasic organic acid includes one or more of aminotri(methylene) phosphonic acid, hydroxyethylidene diphosphonic acid, 2-phosphono-1,2,4-tricarboxy butane, diethylene triamine penta(methylene) phosphonic acid, 2-hydroxyphosphono acetic acid and polyamino polyether methylene phosphonic acid.

5. The sulphur-containing cyclic cooling water scale and corrosion inhibitor of claim 1, wherein, The zinc salt includes zinc sulfate.

6. The sulphur-containing cyclic cooling water scale and corrosion inhibitor of claim 1, wherein, The acrylic acid homopolymer or copolymer includes one or more of polyacrylic acid and acrylic acid-2-methyl-2-acrylamidopropyl sulfonic acid copolymer.

7. The sulphur cycle cooling water scale and corrosion inhibitor of claim 1, wherein, The copper buffer includes an alkaline aqueous solution of methyl benzotriazole or benzotriazole with a concentration of 25-35 wt%, and the pH value is > 12.

8. The sulphur cycle cooling water scale and corrosion inhibitor of claim 1, wherein, The water-soluble imidazoline includes a double alkyl imidazoline quaternary ammonium salt.

9. A method of using a sulphur-containing cyclic cooling water corrosion and scale inhibitor according to any one of claims 1 to 8, characterised in that, The method comprises the following steps: The scale and corrosion inhibitor is added into the circulating cooling water at a dosage of 100-300 mg / L for operation.

10. The method of using a sulphur cycle cooling water scale and corrosion inhibitor according to claim 9, wherein, When the sulfide content in the circulating cooling water is < 2.0 mg / L, the dosage of the scale and corrosion inhibitor is 100-200 mg / L; and when the sulfide content in the circulating cooling water is ≥ 2.0 mg / L, the dosage of the scale and corrosion inhibitor is 200-300 mg / L.

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