An environmentally friendly anti-scaling agent for heating pipe network

Abstract

The present invention provides an environmentally friendly anti-scaling agent for a heating network, which is prepared by malic acid-aspartic acid-cationic starch telomer, zinc gluconate and pure water in a certain proportion. The anti-scaling agent prepared by the present invention is added to the hot water of the heating network, which can effectively prevent the deposition and precipitation of scaling substances in the hot water, eliminate the scaling phenomenon on the heat transfer surface of the heat exchanger, greatly improve the heat transfer efficiency, and have a significant energy-saving effect. After the anti-scaling agent is added to the water system of the heating network, it can also significantly reduce the corrosion rate of metals in the heating network, effectively eliminate the corrosion and leakage phenomenon of the network, avoid the occurrence of heating shutdown accidents, and save maintenance costs. The anti-scaling agent does not contain phosphorus compounds, and will not cause phosphorus-enriched pollution in the water environment after discharge. The anti-scaling agent is prepared using food additive raw materials, which is non-toxic, harmless and safer for users.

Description

Technical Field

[0001] The invention relates to an environmentally friendly anti-scaling agent for a heating pipe network, and belongs to the field of heating production. Background Art

[0002] During the operation of the heating network, the metal heat transfer surface is prone to corrosion and rust, and process scale and corrosion products are produced. Since the thermal conductivity of metal rust and scale is very small, the heat transfer efficiency of the heat exchange equipment in the heating network is greatly reduced, and the energy consumption of the heating network operation is greatly increased; scaling and corrosion can also cause leakage of heat exchange equipment, channel blockage, pipe burst and other operational safety accidents, resulting in property losses and increased system maintenance costs, further increasing the production costs of heating companies. Heating companies often add anti-scaling agents to ensure safe and low-energy operation of heating equipment and pipe network systems.

[0003] So far, most of the anti-scaling agents used in heating pipe networks contain organic phosphine or inorganic phosphorus compounds. These anti-scaling agents containing chemical phosphorus elements will cause eutrophication of surface water systems after discharge, affecting the living environment of aquatic organisms; and the chemical components in the products are not easily degraded by microorganisms after discharge. For example, patent ZL110550751A discloses a heat pipe network anti-scaling agent, which is composed of polyepoxysuccinic acid, phosphorus pentoxide, hypochlorous acid, molybdate, zinc sulfate, sodium phosphate, hydroxyethylidene diphosphonic acid, hexamethylenetetramine and pure water. The patent formula contains a variety of inorganic and organic phosphorus compounds, which pollute the water environment and are not easy to degrade after discharge. For example, patent CN110127871A discloses a new type of anti-scaling agent that can be used in heating pipe networks, which is a single-component compound O-O'-di(isopropyl) dithiophosphoric acid triethylamine. This component is a phosphorus-containing organic compound. After discharge, it will cause phosphorus enrichment of surface water systems and is not easily biodegradable, polluting the environment.

[0004] Patent CN106830375A discloses a hot water boiler scale inhibitor, which is composed of tannin extract, fatty alcohol polyoxyethylene ether and water. Tannin extract in the formula is easy to coke on the heat transfer surface of the hot water boiler, generating carbon scale that is heat-insulating and extremely difficult to clean, causing safety accidents such as bulging and deformation of the boiler heat transfer surface and bursting of pipes. Summary of the invention

[0005] The purpose of the present invention is to provide a green, safe, non-toxic and easily degradable environmentally friendly anti-scaling agent for heating pipe networks in order to solve the problems of phosphorus-rich pollution and poor biodegradability in the prior art.

[0006] The environmentally friendly anti-scaling agent for the heating pipe network of the present invention is prepared from malic acid-aspartic acid-cationic starch telomer, zinc gluconate and purified water. The specific raw material ratio and preparation process are as follows:

[0007] The raw material ratio (by weight): 30-40 parts of malic acid-aspartic acid-cationic starch telomer, 8-15 parts of zinc gluconate, and the balance is purified water.

[0008] Preparation process: add pure water and zinc gluconate into a stainless steel reactor, heat to 40-50°C, adjust the stirring speed to 60r / min, stir for 15-20min, slowly add malic acid-aspartic acid-cationic starch polymer, heat to 60-75°C, adjust the stirring speed to 80r / min, continuously stir and react for 30-40min, cool to 25-30°C, stop stirring and let stand for 20-30min, filter to remove suspended matter, and obtain an environmentally friendly anti-scaling agent for the heating pipe network.

[0009] The raw material ratio and preparation process of the above malic acid-aspartic acid-cationic starch telomer are as follows:

[0010] Raw material ratio (by weight): 10-15 parts of malic acid, 5-10 parts of aspartic acid, 10-20 parts of cationic starch, and the balance is purified water;

[0011] Preparation process: add pure water into a stainless steel reactor, heat to 30-40°C, add malic acid, stir for 10-15 minutes, heat to 60-70°C while stirring, slowly add aspartic acid (add within 5 minutes), stir and react for 30-40 minutes; adjust the stirring speed to 90r / min, slowly add cationic starch (add within 5 minutes) under nitrogen protection, heat to 85-90°C, stir and react for 2-3 hours; cool to 20-30°C, and let stand for 15-20 minutes.

[0012] The effect of the antiscalant prepared by the present invention and its impact on the environment are explained below through experiments.

[0013] 1. Significant anti-scaling and anti-corrosion effects

[0014] According to each m 3 Add 50-80g of the scale inhibitor of the present invention to the hot water for heating, and continuously add it to the heating pipe network system, circulate and mix evenly and run normally. After being used by 11 domestic heating companies for 3 years, an inspection after the heating period ended found that the heat transfer surface of the heat exchange equipment in the system and the metal surface of the hot water delivery pipe had no scale and rust, and the metal surface was clean and smooth, forming a uniform and complete anti-corrosion protective film. The average corrosion rate of carbon steel measured by the standard corrosion test piece hung in the hot water pipe is less than 0.01g / m 2 .h; copper less than 0.003g / m 2 .h. No corrosion or leakage occurred in the heating system. In the heating system without the anti-scaling agent of the present invention, the heat exchange equipment was scaled and rusted after running for 6 months. The average corrosion rate measured by the standard corrosion monitoring test piece was: carbon steel was greater than 0.26g / m2 .h, copper greater than 0.06g / m 2 .h, cleaning and descaling are carried out after the heating period ends every year, and the parts damaged by corrosion in the system are repaired and replaced. This shows that the anti-scaling agent of the present invention has good anti-scaling and anti-corrosion effects.

[0015] 2. Phosphorus-free formula has a good effect in protecting the environment

[0016] The phosphorus-containing antiscaling agents currently in use will increase the phosphorus content in surface waters and cause eutrophication after discharge, which will in turn trigger the rapid reproduction and growth of algae microorganisms in the water bodies, causing serious water pollution environmental accidents.

[0017] The anti-scaling agent formula of the present invention does not contain organic phosphorus and inorganic phosphorus compounds, and will not cause eutrophication of surface water after discharge, and will not cause adverse effects on the water environment.

[0018] 3. The raw materials are non-toxic and biosafe

[0019] The raw materials for synthesizing the anti-scaling agent of the present invention are all food additive raw materials, which are non-toxic, tasteless and harmless. According to the test of the provincial disease prevention and control center, the LD50 is greater than 10.0g / kg, which is practically non-toxic. The product is safe and harmless to the health of operators and contact persons during use and after discharge.

[0020] In summary, the anti-scaling agent prepared by the present invention is added to the hot water of the heating network, which can effectively prevent the deposition and precipitation of scaling substances in the hot water, eliminate the scaling phenomenon on the heat transfer surface of the heat exchanger, greatly improve the heat transfer efficiency, and achieve significant energy-saving effects. After the anti-scaling agent is added to the hot water system, it can also significantly reduce the corrosion rate of metals in the heating network, effectively eliminate the corrosion and leakage phenomenon of the network, avoid the occurrence of heating outage accidents, and save maintenance costs. After being added and used in the heating network by 11 domestic heating companies, it has achieved good anti-scaling and energy-saving effects and anti-corrosion and life extension effects of the network system, improved the heating production efficiency, saved heating costs, and reduced carbon emissions. In addition, the anti-scaling agent does not contain phosphorus compounds, and will not cause phosphorus-rich pollution in the water environment after discharge. The anti-scaling agent is prepared with food additive raw materials, which is non-toxic, harmless and safer for users. DETAILED DESCRIPTION

[0021] Example 1

[0022] (1) The raw material ratio and preparation process of malic acid-aspartic acid-cationic starch telomer are as follows:

[0023] Raw material ratio (by weight): 10 parts of malic acid, 10 parts of aspartic acid, 10 parts of cationic starch, and the balance is purified water;

[0024] Preparation process: add pure water into a stainless steel reactor, heat to 35°C, add malic acid, stir for 10 minutes, heat to 65°C while stirring, slowly add aspartic acid (added within 5 minutes), stir and react for 35 minutes; adjust the stirring speed to 90r / min, slowly add cationic starch (added within 5 minutes) under nitrogen protection, heat to 85°C, stir and react for 2.5 hours; cool to 25°C, let stand for 15 minutes to obtain malic acid-aspartic acid-cationic starch polymer.

[0025] (2) The raw material ratio and preparation process of the environmentally friendly anti-scaling agent for heating pipe network are as follows:

[0026] Raw material ratio: including the following raw materials in percentage by weight: 30% malic acid-aspartic acid-cationic starch telomer; 15% zinc gluconate; and the balance pure water.

[0027] Preparation process: Add pure water and zinc gluconate into a stainless steel reactor, heat to 45°C, adjust the stirring speed to 60r / min, stir for 15 minutes, slowly add malic acid-aspartic acid-cationic starch polymer, heat to 65°C, adjust the stirring speed to 80r / min, stir continuously for 35 minutes, cool to 25°C, stop stirring and let stand for 25 minutes, filter to remove suspended matter, and obtain an environmentally friendly anti-scaling agent for the heating network.

[0028] Example 2

[0029] (1) The raw material ratio and preparation process of malic acid-aspartic acid-cationic starch telomer are as follows:

[0030] Raw material ratio (by weight): 10 parts of malic acid, 5 parts of aspartic acid, 20 parts of cationic starch, and the balance is purified water;

[0031] Preparation process: same as Example 1;

[0032] (2) The raw material ratio and preparation process of the environmentally friendly anti-scaling agent for heating pipe network are as follows:

[0033] Raw material ratio: including the following raw materials in percentage by weight: 40% malic acid-aspartic acid-cationic starch telomer; 8% zinc gluconate; the balance is purified water;

[0034] Preparation process: Same as Example 1.

[0035] Example 3

[0036] (1) The raw material ratio and preparation process of malic acid-aspartic acid-cationic starch telomer are as follows:

[0037] Raw material ratio (by weight): 15 parts of malic acid, 10 parts of aspartic acid, 10 parts of cationic starch, and the balance is purified water;

[0038] Preparation process: same as Example 1;

[0039] (2) The raw material ratio and preparation process of the environmentally friendly anti-scaling agent for heating pipe network are as follows:

[0040] Raw material ratio: including the following raw materials in percentage by weight: 35% malic acid-aspartic acid-cationic starch telomer; 10% zinc gluconate; the balance pure water;

[0041] Preparation process: Same as Example 1.

[0042] Example 4

[0043] (1) The raw material ratio and preparation process of malic acid-aspartic acid-cationic starch telomer are as follows:

[0044] Raw material ratio (by weight): 15 parts of malic acid, 10 parts of aspartic acid, 20 parts of cationic starch, and the balance is purified water;

[0045] Preparation process: same as Example 1;

[0046] (2) The raw material ratio and preparation process of the environmentally friendly anti-scaling agent for heating pipe network are as follows:

[0047] Raw material ratio: including the following raw materials in percentage by weight: 40% malic acid-aspartic acid-cationic starch telomer; 15% zinc gluconate; the balance is purified water;

[0048] Preparation process: Same as Example 1.

[0049] The evaluation method of the scale inhibition and corrosion inhibition performance of the environmentally friendly antiscalant for the heating network obtained in the above examples refers to the industry standard of the People's Republic of China "Dynamic Method for Evaluation of Performance of Boiler Water Treatment Agents" (HG / T3924-2007), in which the determination of the scale inhibition performance of calcium carbonate is combined with the "Calcium Carbonate Deposition Method" (GB / T16632-2019). Examples 1-3 are tested according to the prepared water samples specified in national standards or industry standards, and Example 4 is tested directly with tap water.

[0050] The test results are as follows:

[0051]

[0052] The above embodiments all demonstrate that the environmentally friendly antiscalant for the heating pipe network of the present invention has excellent antiscaling and corrosion inhibition performance.

Claims

1. An environmentally friendly anti-scaling agent for a heating pipe network is prepared from malic acid-aspartic acid-cationic starch telomer, zinc gluconate and purified water; the specific raw material ratio and preparation process are as follows: Raw material ratio: each raw material is calculated by weight, 30-40 parts of malic acid-aspartic acid-cationic starch telomer, 8-15 parts of zinc gluconate, and the balance is purified water; Preparation process: add purified water and zinc gluconate into a stainless steel reactor, heat to 40-50°C, adjust the stirring speed to 60r / min, stir for 15-20min, slowly add malic acid-aspartic acid-cationic starch telomer, heat to 60-75°C, adjust the stirring speed to 80r / min, continuously stir and react for 30-40min, cool to 25-30°C, stop stirring and let stand for 20-30min, filter and remove suspended matter, and obtain an environmentally friendly anti-scaling agent for a heating pipe network; The raw material ratio and preparation process of the malic acid-aspartic acid-cationic starch telomer are as follows: Raw material ratio: by weight, 10-15 parts of malic acid, 5-10 parts of aspartic acid, 10-20 parts of cationic starch, and the balance is purified water; Preparation process: add pure water into a stainless steel reactor, heat to 30-40°C, add malic acid, stir for 10-15 minutes, heat to 60-70°C while stirring, slowly add aspartic acid, stir and react for 30-40 minutes; adjust the stirring speed to 90r / min, slowly add cationic starch under nitrogen protection, heat to 85-90°C, stir and react for 2-3 hours; cool to 20-30°C, let stand for 15-20 minutes to obtain malic acid-aspartic acid-cationic starch telomer.

2. An environmentally friendly anti-scaling agent for a heating pipe network as claimed in claim 1, characterized in that: The aspartic acid and cationic starch were added within 5 minutes.

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