High-salt scale inhibitor suitable for high-salt wastewater multi-evaporation working condition and use method thereof

Abstract

The invention relates to a high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation working conditions and a use method, the scale inhibitor is composed of polyaspartic acid, polyepoxysuccinic acid, hydroxyethylidene diphosphonic acid, polymaleic anhydride, a composite quaternary ammonium salt, 2-phospho-1, 2, 4-tricarboxylic acid butane, a pH regulator, sodium persulfate, an antirust agent and a preservative, and has excellent scale inhibition performance. By using the scale inhibitor, the heat transfer efficiency of an evaporator can be remarkably improved, the service life of equipment can be prolonged, and the scale inhibitor is suitable for relieving aggregation and caking of salt on the wall surface of a quench tower under the condition of quench back-injection evaporation of high-salt wastewater; the evaporator is also suitable for relieving attached deposition of salt on the inner wall surface of the evaporator under the condition of multi-effect, double-effect and single-effect evaporation of high-salt wastewater; the scale inhibitor has excellent scale inhibition performance, can effectively prevent high-salinity wastewater from forming a scale layer under a multi-evaporation working condition, is simple and easy to understand in use method, is convenient to operate, and is suitable for a large-scale high-salinity wastewater treatment process.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, in particular to a high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions and a use method thereof. Background Art

[0002] In the production process of chemical, electric power, pharmaceutical and other industries, a large amount of high-salt wastewater is generated. These wastewaters contain a variety of substances, including salt, oil, organic heavy metals, etc., which cause serious pollution to the environment. The treatment of high-salt wastewater has always been a difficult problem in the field of environmental protection. Especially under multi-evaporation conditions, the salt in the wastewater is easy to crystallize in the evaporator and equipment pipelines to form a scale layer, which in turn affects the heat transfer efficiency and service life of the evaporator and equipment pipelines.

[0003] High-salt scale inhibitors are special treatment aids developed for high-salt, high-temperature concentration systems that are prone to scaling and hardening; they are mainly composed of macromolecular chelating dispersants, sparingly soluble salt surface modifiers and other substances. They achieve their purpose by changing the formation and growth process of inorganic salt nuclei. They can be used to inhibit the evaporation and concentration of wastewater. Scale inhibitors use a variety of polymers and salt surface modifiers to disperse the precipitated salt and ash, and have a strong inhibitory effect on the formation of inorganic scale, so that the salt formed by the evaporation of high-salt wastewater can be dispersed and fall to the bottom of the quench tower, and no longer deposited on the inner wall of the quench tower.

[0004] Therefore, it is of great significance to develop a high-salt scale inhibitor suitable for high-salt wastewater evaporation conditions. Summary of the invention

[0005] In view of the problems in the prior art, the present invention provides a high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions and a method of use.

[0006] The technical solution adopted by the present invention to solve its technical problem is:

[0007] A high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions, the high-salt scale inhibitor is made of the following components in percentage by mass:

[0008] Polyaspartic acid 12-18%, polyepoxysuccinic acid 10-20%, hydroxyethylidene diphosphonic acid 15-25%, polymaleic anhydride 5-10%, composite quaternary ammonium salt 5-12%, 2-phospho-1,2,4-tricarboxylic acid butane 3-8%, pH adjuster 2-5%, sodium persulfate 5-8%, rust inhibitor 5-8%, preservative 5-8%.

[0009] Preferably, the high-salt scale inhibitor is made of the following components in percentage by mass:

[0010] Polyaspartic acid 15%, polyepoxysuccinic acid 18%, hydroxyethylidene diphosphonic acid 20%, polymaleic anhydride 8%, composite quaternary ammonium salt 12%, 2-phospho-1,2,4-tricarboxylic acid butane 5%, pH adjuster 3%, sodium persulfate 5%, rust inhibitor 8%, preservative 6%.

[0011] Preferably, the high-salt scale inhibitor is made of the following components in percentage by mass:

[0012] Polyaspartic acid 18%, polyepoxysuccinic acid 15%, hydroxyethylidene diphosphonic acid 17%, polymaleic anhydride 5%, composite quaternary ammonium salt 9%, 2-phospho-1,2,4-tricarboxylic acid butane 8%, pH adjuster 5%, sodium persulfate 8%, rust inhibitor 7%, preservative 8%.

[0013] Preferably, the high-salt scale inhibitor is made of the following components in percentage by mass:

[0014] Polyaspartic acid 12%, polyepoxysuccinic acid 20%, hydroxyethylidene diphosphonic acid 25%, polymaleic anhydride 10%, composite quaternary ammonium salt 9%, 2-phospho-1,2,4-tricarboxylic acid butane 3%, pH adjuster 5%, sodium persulfate 6%, rust inhibitor 5%, preservative 5%.

[0015] Preferably, the high-salt scale inhibitor further comprises auxiliary ingredients such as a softener and a dispersant.

[0016] Preferably, the polymaleic anhydride is acrylic acid.

[0017] Preferably, the pH adjuster is any one of sodium hydroxide, potassium hydroxide and ammonia water.

[0018] A method for using a high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions, comprising the following steps:

[0019] 3) Pre-treat high-salinity wastewater, such as softening treatment, to remove some hardness and impurities in the wastewater;

[0020] 4) During use, the salt content in high-salt wastewater needs to be tested, and the amount of scale inhibitor used needs to be determined based on the salt composition;

[0021] 3) Add the prepared antiscalant into the pretreated high-salt wastewater in batch or flow addition mode to ensure that the antiscalant is evenly dispersed in the wastewater;

[0022] 4) The high-salt wastewater after adding the scale inhibitor is passed into the multiple-effect evaporator for evaporation treatment. During the evaporation process, the scale inhibitor can effectively prevent the wastewater from scaling on the inner wall of the evaporator and the equipment pipeline;

[0023] 5) According to the needs, the amount of antiscalant added and the operating parameters of the evaporator can be adjusted to achieve the best antiscaling effect and evaporation efficiency;

[0024] 6) During the evaporation process, regularly check the heat transfer efficiency and equipment condition of the evaporator, and make adjustments and maintenance as needed.

[0025] Compared with the prior art, the invention has the following beneficial effects: the invention discloses a high-salt scale inhibitor and a method of use suitable for high-salt wastewater multi-evaporation conditions, adopts a variety of polymers and salt surface modifiers, has a good dispersing effect on precipitated salt and ash, has a strong inhibitory effect on the formation of inorganic scale, so that the salt formed by the evaporation of high-salt wastewater can be dispersed and fall off to the bottom of the quenching tower, and no longer deposited and attached to the inner wall of the quenching tower. The invention is suitable for alleviating the aggregation and agglomeration of salt on the wall surface of the quenching tower under the condition of rapid cooling and back-spray evaporation of high-salt wastewater; it is also suitable for alleviating the adhesion and deposition of salt on the inner wall surface of the evaporator under the condition of multi-effect, double-effect and single-effect evaporation of high-salt wastewater; it has excellent scale inhibition performance and can effectively prevent high-salt wastewater from forming a scale layer under multi-evaporation conditions; the use of the scale inhibitor of the invention can improve the heat transfer efficiency of the evaporator and the service life of the equipment; the method of use is simple and easy to understand, easy to operate, and suitable for large-scale high-salt wastewater treatment processes. DETAILED DESCRIPTION

[0026] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0027] The invention discloses a high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation working conditions. The high-salt scale inhibitor is prepared from the following components in percentage by mass: 12-18% of polyaspartic acid, 10-20% of polyepoxysuccinic acid, 15-25% of hydroxyethylidene diphosphonic acid, 5-10% of polymaleic anhydride, 5-12% of composite quaternary ammonium salt, 3-8% of 2-phospho-1,2,4-tricarboxylic acid butane, 2-5% of pH regulator, 5-8% of sodium persulfate, 5-8% of rust inhibitor and 5-8% of preservative.

[0028] The high-salt scale inhibitor also contains auxiliary components such as a softener and a dispersant.

[0029] The polymaleic anhydride is acrylic acid.

[0030] The pH adjuster is any one of sodium hydroxide, potassium hydroxide and ammonia water.

[0031] A method for using a high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions, comprising the following steps:

[0032] 1) Pre-treat high-salinity wastewater, such as softening treatment, to remove some hardness and impurities in the wastewater;

[0033] 2) During use, the salt content in high-salt wastewater needs to be tested, and the amount of scale inhibitor used needs to be determined based on the salt composition;

[0034] 3) Add the prepared antiscalant into the pretreated high-salt wastewater in batch or flow addition mode to ensure that the antiscalant is evenly dispersed in the wastewater;

[0035] 4) The high-salt wastewater after adding the scale inhibitor is passed into the multiple-effect evaporator for evaporation treatment. During the evaporation process, the scale inhibitor can effectively prevent the wastewater from scaling on the inner wall of the evaporator and the equipment pipeline;

[0036] 5) According to the needs, the amount of antiscalant added and the operating parameters of the evaporator can be adjusted to achieve the best antiscaling effect and evaporation efficiency;

[0037] 6) During the evaporation process, regularly check the heat transfer efficiency and equipment condition of the evaporator, and make adjustments and maintenance as needed.

[0038] Table 1: 13m3 / h brine consumption, salt inhibitor dosage

[0039] Brine pump flow (m3 / h) Salt content (%) Salt inhibitor dosage (L / h) Metering pump flow rate (mL / s) 13 1 1.7 0.5 13 2 3.4 0.9 13 3 5.1 1.4 13 4 6.8 1.9 13 5 8.5 2.3 13 6 10.1 2.8 13 7 11.8 3.3 13 8 13.5 3.8 13 9 15.2 4.2 13 10 16.9 4.7 13 11 18.6 5.2 13 12 20.3 5.6 13 13 22.0 6.1 13 14 23.7 6.6 13 15 25.4 7.0 13 16 27.0 7.5 13 17 28.7 8.0 13 18 30.4 8.5 13 19 32.1 8.9 13 20 33.8 9.4

[0040] Where, the amount of salt blocking agent (L / h) = the amount of salt water (m 3 / h)*salt content (%)*13, that is, 13L of salt inhibitor is needed to convert 1 ton of salt.

[0041] Table 2: 13m3 / h brine consumption, salt inhibitor dosage

[0042]

[0043]

[0044] Where, the amount of salt blocking agent (L / h) = the amount of salt water (m 3 / h)*salt content (%)*13, that is, 13L of salt inhibitor is needed to convert 1 ton of salt.

[0045] Embodiment 1:

[0046] The high-salt scale inhibitor is made of the following components in percentage by mass: 15% polyaspartic acid, 18% polyepoxysuccinic acid, 20% hydroxyethylidene diphosphonic acid, 8% polymaleic anhydride, 12% composite quaternary ammonium salt, 5% 2-phospho-1,2,4-tricarboxylic acid butane, 3% pH regulator, 5% sodium persulfate, 8% rust inhibitor, and 6% preservative.

[0047] A certain amount of high-salt wastewater is pretreated to remove some hardness and impurities. Then, the scale inhibitor mixed in the above proportion is added to the pretreated high-salt wastewater to ensure that the scale inhibitor is evenly dispersed in the wastewater. The high-salt wastewater to which the scale inhibitor is added is passed into a multiple-effect evaporator for evaporation treatment. During the evaporation process, the heat transfer efficiency and equipment condition of the evaporator are regularly checked. The results show that after using the scale inhibitor of the present invention, the high-salt wastewater can be effectively prevented from forming a scale layer under multiple evaporation conditions; the heat transfer efficiency of the evaporator and the service life of the equipment can be improved.

[0048] Embodiment 2:

[0049] The high-salt scale inhibitor is made of the following components in percentage by mass: 18% of polyaspartic acid, 15% of polyepoxysuccinic acid, 17% of hydroxyethylidene diphosphonic acid, 5% of polymaleic anhydride, 9% of composite quaternary ammonium salt, 8% of 2-phospho-1,2,4-tricarboxylic acid butane, 5% of pH regulator, 8% of sodium persulfate, 7% of rust inhibitor and 8% of preservative.

[0050] A certain amount of high-salt wastewater is pretreated to remove some hardness and impurities. Then, the scale inhibitor mixed in the above proportion is added to the pretreated high-salt wastewater to ensure that the scale inhibitor is evenly dispersed in the wastewater. The high-salt wastewater to which the scale inhibitor is added is passed into a multiple-effect evaporator for evaporation treatment. During the evaporation process, the heat transfer efficiency and equipment condition of the evaporator are regularly checked. The results show that after using the scale inhibitor of the present invention, the high-salt wastewater can be effectively prevented from forming a scale layer under multiple evaporation conditions; the heat transfer efficiency of the evaporator and the service life of the equipment can be improved.

[0051] Embodiment 3:

[0052] The high-salt scale inhibitor is made of the following components in percentage by mass: 12% of polyaspartic acid, 20% of polyepoxysuccinic acid, 25% of hydroxyethylidene diphosphonic acid, 10% of polymaleic anhydride, 9% of composite quaternary ammonium salt, 3% of 2-phospho-1,2,4-tricarboxylic acid butane, 5% of pH regulator, 6% of sodium persulfate, 5% of rust inhibitor and 5% of preservative.

[0053] A certain amount of high-salt wastewater is pretreated to remove some hardness and impurities. Then, the scale inhibitor mixed in the above proportion is added to the pretreated high-salt wastewater to ensure that the scale inhibitor is evenly dispersed in the wastewater. The high-salt wastewater to which the scale inhibitor is added is passed into a multiple-effect evaporator for evaporation treatment. During the evaporation process, the heat transfer efficiency and equipment condition of the evaporator are regularly checked. The results show that after using the scale inhibitor of the present invention, the high-salt wastewater can be effectively prevented from forming a scale layer under multiple evaporation conditions; the heat transfer efficiency of the evaporator and the service life of the equipment can be improved.

[0054] In summary, the present invention provides a high-salt scale inhibitor and a method of use suitable for high-salt wastewater multi-evaporation conditions. The invention adopts a variety of polymers and salt surface modifiers to disperse the precipitated salt and ash, and has a strong inhibitory effect on the formation of inorganic scale, so that the salt formed by the evaporation of high-salt wastewater can be dispersed and fall to the bottom of the quenching tower, and no longer deposited and attached to the inner wall of the quenching tower. The invention is suitable for alleviating the aggregation and agglomeration of salt on the wall of the quenching tower under the condition of rapid cooling and back-spray evaporation of high-salt wastewater; it is also suitable for alleviating the adhesion and deposition of salt on the inner wall of the evaporator under the condition of multi-effect, double-effect and single-effect evaporation of high-salt wastewater; it has excellent scale inhibition performance and can effectively prevent high-salt wastewater from forming a scale layer under multi-evaporation conditions; the use of the scale inhibitor of the present invention can improve the heat transfer efficiency of the evaporator and the service life of the equipment; the method of use is simple and easy to understand, and the operation is convenient, and it is suitable for large-scale high-salt wastewater treatment processes.

[0055] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A high-salt scale inhibitor suitable for high-salt wastewater evaporation conditions, characterized by: High salt scale inhibitor is made of the following components in percentage by mass: Polyaspartic acid 12-18%, polyepoxysuccinic acid 10-20%, hydroxyethylidene diphosphonic acid 15-25%, polymaleic anhydride 5-10%, composite quaternary ammonium salt 5-12%, 2-phospho-1,2,4-tricarboxylic acid butane 3-8%, pH adjuster 2-5%, sodium persulfate 5-8%, rust inhibitor 5-8%, preservative 5-8%.

2. A high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions according to claim 1, characterized in that: The high-salt scale inhibitor is made of the following components in percentage by mass: Polyaspartic acid 15%, polyepoxysuccinic acid 18%, hydroxyethylidene diphosphonic acid 20%, polymaleic anhydride 8%, composite quaternary ammonium salt 12%, 2-phospho-1,2,4-tricarboxylic acid butane 5%, pH adjuster 3%, sodium persulfate 5%, rust inhibitor 8%, preservative 6%.

3. A high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions according to claim 1, characterized in that: The high-salt scale inhibitor is made of the following components in percentage by mass: Polyaspartic acid 18%, polyepoxysuccinic acid 15%, hydroxyethylidene diphosphonic acid 17%, polymaleic anhydride 5%, composite quaternary ammonium salt 9%, 2-phospho-1,2,4-tricarboxylic acid butane 8%, pH adjuster 5%, sodium persulfate 8%, rust inhibitor 7%, preservative 8%.

4. A high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions according to claim 1, characterized in that: The high-salt scale inhibitor is made of the following components in percentage by mass: Polyaspartic acid 12%, polyepoxysuccinic acid 20%, hydroxyethylidene diphosphonic acid 25%, polymaleic anhydride 10%, composite quaternary ammonium salt 9%, 2-phospho-1,2,4-tricarboxylic acid butane 3%, pH adjuster 5%, sodium persulfate 6%, rust inhibitor 5%, preservative 5%.

5. The high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions according to claim 1, characterized in that: The high-salt scale inhibitor also contains auxiliary components such as a softener and a dispersant.

6. The high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions according to claim 1, characterized in that: The polymaleic anhydride is acrylic acid.

7. The high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions according to claim 1, characterized in that: The pH adjuster is any one of sodium hydroxide, potassium hydroxide and ammonia water.

8. A method for using a high-salt scale inhibitor suitable for high-salt wastewater multi-evaporation conditions, comprising the following steps: 1) Pre-treat high-salinity wastewater, such as softening treatment, to remove some hardness and impurities in the wastewater; 2) During use, the salt content in high-salt wastewater needs to be tested, and the amount of scale inhibitor used needs to be determined based on the salt composition; 3) Add the prepared antiscalant into the pretreated high-salt wastewater in batch or flow addition mode to ensure that the antiscalant is evenly dispersed in the wastewater; 4) The high-salt wastewater after adding the scale inhibitor is passed into the multiple-effect evaporator for evaporation treatment. During the evaporation process, the scale inhibitor can effectively prevent the wastewater from scaling on the inner wall of the evaporator and the equipment pipeline; 5) According to the needs, the amount of antiscalant added and the operating parameters of the evaporator can be adjusted to achieve the best antiscaling effect and evaporation efficiency; 6) During the evaporation process, regularly check the heat transfer efficiency and equipment condition of the evaporator, and make adjustments and maintenance as needed.

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