Composite medicament for regulating boiler water quality and application thereof

Abstract

The invention relates to the technical field of water treatment, and particularly discloses a boiler water quality adjusting composite agent and application thereof.The boiler water quality adjusting composite agent comprises a general function organic composite agent, a neutralization function organic composite agent and a deoxygenation function organic composite agent. According to the real-time steam-water index of the boiler, composite chemicals with different functions are intelligently added, the dosage is accurately controlled, the steam-water index can be rapidly stabilized, the index fluctuation range is reduced, the risks of chemical adding errors, excessive chemical adding and the like are reduced, meanwhile, the labor intensity of operators is greatly reduced, the boiler steam-water quality is improved, the pollution discharge rate of the boiler is reduced, and energy is saved. And safe and efficient operation of the boiler is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of water treatment, in particular to a boiler water quality regulating composite agent and application thereof. BACKGROUND

[0002] The drum boiler system is widely used in industrial production. How to realize the non-occurrence of phenomena such as scale and corrosion on the metal surface of the water side of the boiler is a big problem in current industrial water treatment. The traditional commonly used agent formula for boiler water treatment is the "three sodium and one glue" method and the "four sodium" method, and the action mechanism of descaling is that the insoluble calcium and magnesium salts in the scale react with trisodium phosphate to generate water-soluble phosphate; the reaction product further reacts with the calcium salt in the scale to form a calcium salt precipitate, which is then carried away by the blowdown water flow. The congenital defect of the phosphate action mechanism leads to excessive blowdown, which not only increases the cost of desalination chemical water treatment, but also increases the fuel consumption of the boiler, thereby inevitably increasing the operation cost of the boiler. Moreover, frequent opening of the valve for blowdown not only increases the labor consumption, but also reduces the service life of the valve.

[0003] In recent years, some companies have used composite agents to control the water vapor indicators in the furnace, but since all the functional agents are mixed together in a certain proportion in advance, the excessive addition of other functional agent components will occur due to the control of one indicator, which artificially increases the impurity content of the boiler water and wastes costs. Not only does it affect the safe operation of the boiler, but it also poses a serious threat to the normal operation of the downstream steam pipe network and steam-using equipment. Manufacturers must constantly change the formula to solve this problem, which will lead to delayed problem processing, increased labor intensity and labor costs.

[0004] The above problems show that reducing the blowdown rate of industrial drum boilers and improving the quality of steam are important topics in the field of boiler water treatment. Therefore, there is an urgent need for a new type of organic chemical water treatment agent, which can intelligently add different functional composite agents and accurately control the amount of the agent added according to the real-time steam and water indicators of the boiler, to replace the traditional phosphate water treatment process, improve the quality of steam and water of the boiler, reduce the blowdown rate of the boiler, save energy, and ensure the safe and efficient operation of the boiler. SUMMARY

[0005] To solve the problems mentioned in the background art, the purpose of the present application is to provide a boiler water quality regulating composite agent.

[0006] To achieve the above-mentioned objectives, the technical solution of the present application is as follows:

[0007] The boiler water quality adjusting composite agent comprises a general function organic composite agent, a neutralization function organic composite agent and an oxygen removal function organic composite agent, the general function organic composite agent comprises the following components in mass percentage: 3-18% of organic polyamine corrosion inhibitor, 2-15% of polycarboxylate dispersant, 3-10% of organic scale inhibitor, 0.1-2% of emulsifier, 0.2-1% of defoaming agent, and the rest is desalted water; the neutralization function organic composite agent comprises the following components in mass percentage: 5-20% of cyclohexylamine, 5-15% of monoethanolamine, 3-10% of diethylenetriamine, 5-20% of diethanolamine, 3-15% of isopropylamine, and the rest is desalted water; the oxygen removal function organic composite agent comprises the following components in mass percentage: 3-15% of dimethyl ketoxime, 2-10% of carbazic acid hydrazide, and the rest is desalted water.

[0008] In the general function organic composite agent, the organic polyamine corrosion inhibitor has a polar amine group and a non-polar alkyl group, can contact the metal at multiple places, changes the charge state and interface properties of the metal surface, stabilizes the energy state, and thus reduces the corrosion reaction tendency; meanwhile, the non-polar group forms a hydrophobic protective film, which acts as a barrier between water and metal, hinders the movement of corrosive substances to the metal surface, and prevents the corrosion of the metal; the polycarboxylate dispersant plays a role in dispersion and stabilization by reducing the surface tension, providing electric repulsion and steric hindrance effect, has a large number of carboxyl and amino groups in the molecular structure, can provide good electric repulsion, effectively prevents the aggregation of calcium sulfate and magnesium hydroxide particles, and in addition, the polycarboxylate dispersant has multiple polymer chains in the molecular structure, can provide steric hindrance effect, forms a complex with calcium and magnesium ions in water, and also reduces the deposition of calcium sulfate in the cooling water, and plays a role in dispersion; the organic scale inhibitor plays a role in inhibiting the formation of calcium carbonate scale, calcium sulfate scale, magnesium sulfate scale and the like of the boiler water, can occur chelation reaction with Ca2+, Mg2+, iron, copper, silicon and other ions, destroys or prevents the formation of crystal germination, promotes the distortion of the crystal lattice, and thus peels off the old scale and kills the new scale; the emulsifier plays a role in the blending of the composite agent; the defoaming agent plays a role in reducing the surface tension in water, inhibiting the generation of foam, preventing the accumulation of a large amount of foam in the boiler, penetrating and destroying the surface film structure of the foam, making the foam break and dissipate, and improving the thermal efficiency, reducing the steam mechanical entrainment and preventing and reducing water hammer in the boiler.

[0009] The neutralization function of the organic composite agent is to neutralize the carbonic acid in the recycled water, increase the PH value of the recycled water, neutralize a certain amount of acidic substances, limit the formation of silicon dioxide, effectively remove residual iron rust, improve the exchange efficiency, reduce the iron content in the recycled water, improve the use efficiency of the boiler, adjust the PH value of the boiler water, prevent corrosion caused by high or low PH value, protect the steam pipeline system, and prolong the service life.

[0010] The deoxidization function of the organic composite agent is to remove oxygen in the feed water and boiler water, reduce the dissolved oxygen content, and reduce oxygen corrosion.

[0011] Further, the preparation method of the general function organic composite agent is as follows: a certain amount of desalted water is added to a reaction kettle with stirring device, heated to 42℃ and started to stir, a polycarboxylate dispersant, an organic scale inhibitor, an organic polyamine corrosion inhibitor, an emulsifier, and a defoaming agent are added in sequence, and stirred for 1-2 hours and 30-40 minutes respectively, and then placed for 3 hours.

[0012] Further, the preparation method of the neutralization function organic composite agent is as follows: a certain amount of desalted water is added to a reaction kettle with stirring device, heated to 32℃ and started to stir, cyclohexylamine, monoethanolamine, diethanolamine, and isopropylamine are added in sequence and stirred for 10-15 minutes, then diethylene triamine is added and stirred for 20 minutes, and then placed for 1 hour.

[0013] Further, the preparation method of the deoxidization function organic composite agent is as follows: a certain amount of desalted water is added to a reaction kettle with stirring device, heated to 40℃ and started to stir, dimethyl ketone oxime is added and stirred for 15-20 minutes, then carbazic acid is added and stirred for 30-45 minutes, and then placed for 2 hours.

[0014] Further, the organic polyamine corrosion inhibitor is one or more of dodecylamine, hexadecylamine, heptadecylamine, octadecylamine, and quaternary ammonium salt type imidazoline.

[0015] Further, the polycarboxylate dispersant is one or more of sodium tannate, carboxylic acid-sulfonic acid-acrylate terpolymer, acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer, and maleic acid-acrylic acid copolymer.

[0016] Further, the scale inhibitor is one or more of polyaspartic acid, polyepoxysuccinic acid, nitrilotriacetic acid, and hydrolyzed polymaleic anhydride.

[0017] Further, the emulsifier is one or more of dodecyl dimethyl tertiary amine, polyoxyethylene sorbitan fatty acid ester, and fatty alcohol ether.

[0018] Further, the defoaming agent is one or more of polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropylamine ether, and polyoxypropylene glycerol ether.

[0019] Another object of the present application is to provide an application of the boiler water quality adjusting composite agent, which combines the boiler full-automatic dosing system, intelligently adds composite agents with different functions, and accurately controls the dosing amount according to real-time steam-water indexes of the boiler, so as to stabilize the steam-water indexes and reduce the index fluctuation range.

[0020] The present application has the following beneficial effects: the boiler water quality adjusting composite agent combines the boiler full-automatic dosing system, intelligently adds composite agents with different functions, and accurately controls the dosing amount according to real-time steam-water indexes of the boiler, so as to quickly stabilize the steam-water indexes, reduce the index fluctuation range, reduce the risk of dosing errors and excessive dosing, greatly reduce the labor intensity of the operator, improve the steam-water quality of the boiler, reduce the blowdown rate of the boiler, save energy, and ensure the safe and efficient operation of the boiler; the components of the boiler water quality adjusting composite agent are all organic substances, the products are non-toxic and harmless and do not contain phosphorus, and the sewage discharge has no pollution to the environment. Not only the safety protection ability of the boiler against corrosion, scaling, and salt deposition is improved, but also the blowdown amount of the boiler is greatly reduced, and the waste of energy and water resources is reduced. DETAILED DESCRIPTION

[0021] The technical solutions of the present application will be described clearly and completely below in combination with the embodiments of the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art belong to the protection scope of the present application.

[0022] Embodiment one

[0023] The general function organic composite agent of the boiler water quality adjusting composite agent is used to adjust the high hardness value and conductivity value of the boiler water.

[0024] According to the boiler water quality, the present embodiment includes the following components with the following mass percentage: octadecylamine 8%, carboxylic acid-sulfonic acid-acrylate terpolymer 7%, polyaspartic acid (PASP) 4%, quaternary ammonium salt type imidazoline 5%, fatty alcohol ether 1%, and polyoxypropylene glycerol ether 0.1%, and the rest is desalted water.

[0025] The full-automatic dosing system detects the conductivity and total hardness of the boiler water through the detection sensor, and the computer processes the detection data to modify the adding frequency (how often to add), the adding amount (the amount of the single addition) and the adding speed (the flow of the dosing pump) of the general-purpose organic composite agent, and sends the calculation results to the PLC automatic control module. The PLC automatic control module modifies the control parameters, converts the single addition amount into the height of the general-purpose organic composite agent tank liquid level, opens the general-purpose organic composite agent tank outlet valve, starts the dosing pump, and the dosing pump automatically adjusts to the set flow. When the general-purpose organic composite agent tank liquid level drops to the set height, the dosing pump stops, the general-purpose organic composite agent tank outlet valve is closed, and the full-automatic dosing system waits for the next addition of the general-purpose organic composite agent according to the set time. Before each start of the addition, the size and the rising speed of the detection value are calculated and compared. If the value is higher than the set upper threshold value or the interval time arrives but is not lower than the set lower threshold value, the addition is started. If the value is lower than the set lower threshold value, the addition is not started this time, only the interval time is modified, and the next detection result is continued to be waited for.

[0026] Example Two

[0027] The neutralization function organic composite agent for boiler water quality regulation is used to regulate the low PH value or high SiO2 content of the boiler water.

[0028] According to the boiler water quality regulation, the present example includes the following components with the mass percentage: cyclohexylamine 15%, monoethanolamine 5%, diethanolamine 10%, and isopropylamine 10%, and the rest is desalted water.

[0029] The full-automatic dosing system detects the conductivity and total hardness of the boiler water through the detection sensor, and the computer processes the detection data to modify the adding frequency (how often to add), the adding amount (the amount of the single addition) and the adding speed (the flow of the dosing pump) of the general-purpose organic composite agent, and sends the calculation results to the PLC automatic control module. The PLC automatic control module modifies the control parameters, converts the single addition amount into the height of the general-purpose organic composite agent tank liquid level, opens the general-purpose organic composite agent tank outlet valve, starts the dosing pump, and the dosing pump automatically adjusts to the set flow. When the general-purpose organic composite agent tank liquid level drops to the set height, the dosing pump stops, the general-purpose organic composite agent tank outlet valve is closed, and the full-automatic dosing system waits for the next addition of the general-purpose organic composite agent according to the set time. Before each start of the addition, the size and the rising speed of the detection value are calculated and compared. If the value is higher than the set upper threshold value or the interval time arrives but is not lower than the set lower threshold value, the addition is started. If the value is lower than the set lower threshold value, the addition is not started this time, only the interval time is modified, and the next detection result is continued to be waited for.

[0030] Example three

[0031] The oxygen removal function organic composite agent is used for controlling the dissolved oxygen content of the feed water.

[0032] According to the boiler water quality condition adjustment, the embodiment comprises the following components in percentage by mass: dimethyl ketone oxime 10%, carbohydrazide 3%, and the rest is desalted water.

[0033] When the detection sensor of the full-automatic dosing system monitors that the boiler water dissolved oxygen value rises too fast or exceeds the set upper threshold value, the computer processes and calculates the detection data, modifies the oxygen removal function organic composite agent adding frequency (how often to add), adding amount (single adding agent amount) and adding speed (dosing pump flow), and sends the calculation result to the PLC automatic control module. The PLC automatic control module modifies the control parameters, converts the single dosing amount into the oxygen removal function organic composite agent tank liquid level drop height, opens the oxygen removal function organic composite agent tank outlet valve, starts the dosing pump, and the dosing pump automatically adjusts to the set flow rate operation. When the composite agent tank liquid level drops to the set height, the dosing pump stops, the composite agent tank outlet valve is closed, and the full-automatic dosing system waits for the next oxygen removal function organic composite agent adding according to the set time. Before each starting adding, the size and rising speed of the detection value are calculated and compared. If it is higher than the set upper threshold value or the interval time is reached but not lower than the set lower threshold value, the adding is started. If it is lower than the set lower threshold value, the adding is not started this time, only the interval time is modified, and the next detection result is continued to be waited.

[0034] Example four

[0035] Taking the traditional trisodium phosphate scale inhibitor as a control group, the present embodiment illustrates the direct economic benefits generated after the application of the energy-saving and emission-reducing type boiler water quality adjusting composite agent.

[0036] The basic conditions of one of the circulating fluidized bed coal-fired boilers of a certain thermal power plant are as follows: rated evaporation capacity 450 t / h, rated steam pressure 12.5 MPa, superheated steam temperature 540℃, actual output 300 t / h, thermal efficiency 90%, annual operation hours 8000 hours; the water supplement treatment mode is two-stage cation and anion bed, the treatment cost is 12 yuan / ton, and the actual water supplement amount is 300 t / h; the blowdown mode is continuous blowdown + periodic blowdown, the average hourly blowdown amount is 10.5 t / h (the blowdown rate is about 3.5%), the blowdown water enthalpy value is 1490 KJ / Kg (350℃ saturated water), and the specific heat of water is 4.18 KJ / (Kg.℃). The trisodium phosphate consumption is 12 tons / year, and the price is about 3000 yuan / ton. The current local standard coal (7000 kcal / kg) price is 950 yuan / ton.

[0037] After using the above-mentioned energy-saving and emission-reducing type boiler water quality adjusting composite agent, the boiler has been stably operated for one year in 2022. During the period, the adding amount of the composite agent is about 2.6 kg / h, the total adding amount of the agent in one year is 20.8 tons, the unit price is 55,000 yuan / ton, the opening degree of the continuous blowdown valve is reduced to the minimum opening degree, the fixed blowdown is extended from once a day to once in 15 days, and the average blowdown amount is 1.0 t / h (the blowdown rate is about 0.33%). The PH value of the boiler water is stably maintained between 9.8 and 10.1, the average conductivity of the boiler water is stably maintained between 20 and 30 uS / cm, and the steam silica content is reduced from 9.5 to 12.8 ug / L to 4.5 to 6.0 ug / L. After using for 6 months, a light blue protective film is formed on the heat exchange tube bundle of the high-temperature and low-temperature superheater, the blowdown rate is greatly reduced, the energy loss of blowdown is reduced, the labor intensity of workers is reduced, the failure rate of the valve is reduced, and the safety hidden danger is reduced.

[0038] Comparison table of data of two treatment methods:

[0039] Evaporation capacity 300 t / h Traditional phosphate square Intelligent adjustment system mode Product advantage Pollution rate 3.5％ 0.33％ Reduced by 3.17% Hourly pollution discharge 10.5 tons 1.0 tons Reduced by 9.5 tons / hour Annual total pollution 84,000 tons 8,000 tons Reduced by 76,000 tons / year

[0040] Direct economic benefits of saving:

[0041] Heat saved by saturated water per year: 76000×10 3 Kg / a×1490 KJ / Kg=11324×10 7 KJ / a

[0042] Standard coal saved by saturated water per year (heat value 7000 Kcal / Kg): 11324×10 7 KJ / a÷(7000 Kcal / Kg×4.18×90%)=4300 tons of standard coal / a

[0043] Economic benefits of saving coal per year: 4300 tons×950 yuan / ton of standard coal=408.5 million yuan / year

[0044] Amount of salt water saved per year: 76000 t / a×12 yuan / t=91.2 million yuan

[0045] Cost of using the original agent: 12 t / a×3000 yuan / t=3.6 million yuan

[0046] Cost of using the organic composite agent: 20.8 t / a×55000 yuan / t=114.4 million yuan

[0047] Direct economic benefits of using the energy-saving and emission-reducing type boiler water quality adjusting composite agent:

[0048] 408.5+91.2+3.6-114.4=388.9 million yuan / year

[0049] The above description is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A composite boiler water conditioning agent, characterized by, The general function organic composite agent includes the following mass percentage components: organic polyamine corrosion inhibitor 3-18%, polycarboxylate dispersant 2-15%, organic scale inhibitor 3-10%, emulsifier 0.1-2%, defoaming agent 0.2-1%, and the rest is desalted water; the neutralization function organic composite agent includes the following mass percentage components: cyclohexylamine 5-20%, monoethanolamine 5-15%, diethylenetriamine 3-10%, diethanolamine 5-20%, isopropylamine 3-15%, and the rest is desalted water; the oxygen removal function organic composite agent includes the following mass percentage components: dimethyl ketone oxime 3-15%, carbazic acid 2-10%, and the rest is desalted water.

2. The boiler water conditioning composite agent according to claim 1, characterized by, The preparation method of the general function organic composite agent is as follows: a certain amount of desalted water is added into a reaction kettle with stirring device, heated to 42℃, and then stirred, polycarboxylate dispersant and organic scale inhibitor are added into the reaction kettle, 20 minutes later, organic polyamine corrosion inhibitor is added and stirred for 10-15 minutes, heated to 60-70℃, then emulsifier is added, stirred and dissolved for 1-2 hours, finally defoaming agent is added and stirred for 30-40 minutes, and then placed for 3 hours.

3. The boiler water conditioning composite of claim 1, wherein The preparation method of the neutralization function organic composite agent is as follows: a certain amount of desalted water is added into a reaction kettle with stirring device, heated to 32℃, and then stirred, cyclohexylamine, monoethanolamine, diethanolamine and isopropylamine are added respectively and stirred for 10-15 minutes, then diethylenetriamine is added and stirred for 20 minutes, and then placed for 1 hour.

4. The boiler water conditioning complex agent according to claim 1, characterized by, The preparation method of the oxygen removal function organic composite agent is as follows: a certain amount of desalted water is added into a reaction kettle with stirring device, heated to 40℃, and then stirred, dimethyl ketone oxime is added and stirred for 15-20 minutes, then carbazic acid is added and stirred for 30-45 minutes, and then placed for 2 hours.

5. The boiler water conditioning complex according to claim 1, wherein The organic polyamine corrosion inhibitor is one or more of dodecylamine, hexadecylamine, heptadecylamine, octadecylamine and quaternary ammonium salt type imidazoline.

6. The boiler water conditioning complexing agent according to claim 1, wherein The polycarboxylate dispersant is one or more of sodium tannate, carboxylic acid-sulfonic acid-acrylate terpolymer, acrylic acid-2-acrylamide-2-methylpropane sulfonic acid copolymer and maleic acid-acrylic acid copolymer.

7. The boiler water conditioning complexing agent according to claim 1, wherein The scale inhibitor is one or more of polyaspartic acid, polyepoxysuccinic acid, nitrilotriacetic acid and hydrolyzed polymaleic anhydride.

8. The boiler water conditioning complex according to claim 1, wherein The emulsifier is one or more of dodecyl dimethyl tertiary amine, polyoxyethylene sorbitan fatty acid ester and fatty alcohol ether.

9. The boiler water conditioning complex according to claim 1, wherein The defoaming agent is one or more of polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropylamine ether and polyoxypropylene glycerol ether.

10. The use of the composite boiler water conditioning agent according to any one of claims 1 to 9, characterized in that, The boiler water quality adjusting composite agent is combined with a boiler full-automatic dosing system, and different function composite agents are intelligently added and the dosing amount is accurately controlled according to real-time steam-water indexes of the boiler.