CN115340163B - Paint mist coagulant and preparation method thereof - Google Patents

Abstract

The application discloses a paint mist coagulant and a preparation method thereof, wherein the paint mist coagulant comprises an agent A and an agent B, and the agent A comprises the following components in percentage by mass: 3 to 8 percent of polyaluminum chloride, 0.2 to 1 percent of bentonite, 0.1 to 0.5 percent of methacryloxyethyl trimethyl ammonium chloride, 0.2 to 1 percent of mixed alkali and the balance of water; the component and mass ratio of the agent B are as follows: 0.05 to 0.5 percent of phytic acid, 0.05 to 0.5 percent of alum, 0.05 to 0.5 percent of starch, 0.3 to 0.6 percent of cationic polyacrylamide, 0.05 to 0.5 percent of oxidant and the balance of water. The paint mist coagulant provided by the application can treat various types of paint wastewater, has deodorizing and descaling functions, enables the treated water to be reused for a long time, and can also prevent pipeline scaling.

Description

Paint mist coagulant and preparation method thereof

Technical Field

The application relates to the technical field of industrial wastewater treatment chemical agents, in particular to a paint mist coagulant and a preparation method thereof.

Background

The coating technology is a common means for changing the appearance and performance of the product, and the coating rate of the modern coating technology is generally about 40-60%, namely about half of the coating can be scattered in a paint mist form to be wasted. Wherein, most paint mist is generally absorbed by spray house water curtains and spray towers to form coating wastewater. The COD of the coating wastewater is very high, and is usually about 6000-10000 mg/L. The wastewater discharged to the wastewater treatment end requires a complex process and high cost to be treated to reach the standard. In order to ensure that the water curtain of the spray booth works normally, water is always required to be changed continuously, and the amount of waste water generated by the water curtain is large. Creating tremendous pressure on the enterprise.

From the viewpoint of paint classification, paints used in daily life are classified into aqueous paints and oily paints. There are also many agents currently available on the market for the treatment of these 2 coating wastewaters. For example, CN112028200a discloses a paint mist coagulant suitable for water paint and a preparation method thereof, which is specially used for treating water paint wastewater and has limited application range. In addition, the water treated by the paint mist coagulant can be recycled to a spray room water curtain and a spray tower, and the recycling can last for a plurality of months, so that the problems of water quality stinking and water pipe scaling are easily caused, and the problems that the recycled water is likely to stink and the water pipe scaling are also solved in the process of treating the wastewater by the paint mist coagulant. Therefore, it is highly desirable to develop a versatile and multifunctional paint mist coagulant.

Disclosure of Invention

The present application aims to solve at least one of the technical problems existing in the prior art. Therefore, the paint mist coagulant provided by the application can treat water paint wastewater, oily paint wastewater and wastewater mixed by the water paint wastewater and the oily paint wastewater, and can prevent the odor of reuse water and avoid pipeline scaling.

The application also provides a method for preparing the paint mist coagulant.

An embodiment of a paint mist coagulant according to the first aspect of the present application includes: the agent A comprises the following components in percentage by mass: 3 to 8 percent of polyaluminum chloride, 0.2 to 1 percent of bentonite, 0.1 to 0.5 percent of methacryloxyethyl trimethyl ammonium chloride, 0.2 to 1 percent of mixed alkali and the balance of water; the component and mass ratio of the agent B are as follows: 0.05 to 0.5 percent of phytic acid, 0.05 to 0.5 percent of alum, 0.05 to 0.5 percent of starch, 0.3 to 0.6 percent of cationic polyacrylamide, 0.05 to 0.5 percent of oxidant and the balance of water.

The paint mist coagulant provided by the embodiment of the application has at least the following beneficial effects: the paint mist coagulant can treat water paint wastewater, oily paint wastewater and wastewater mixed by the water paint wastewater and the oily paint wastewater, improves the application range of the paint mist coagulant, and simultaneously, the agent B is added with two functional formulas of phytic acid and an oxidant, so that the paint mist coagulant has the effects of deodorization and scale removal, can enable the treated water to be recycled for a long time, and can prevent pipeline scaling.

According to some embodiments of the application, the mixed base is a mixture of any one or more of sodium hydroxide, triethanolamine, and potassium silicate.

According to some embodiments of the application, the mixed base is a mixture of the sodium hydroxide, the triethanolamine and the potassium silicate, and the mixing ratio of the three is 1: (0.5-1): (0.5-1).

According to some embodiments of the application, the oxidizing agent is one or a mixture of two of potassium persulfate and potassium persulfate.

According to some embodiments of the application, the oxidizing agent is a mixture of potassium persulfate and potassium persulfate, and the mixing ratio of the two is 1: (0.8-1.2).

The preparation method of the paint mist coagulant according to the embodiment of the second aspect of the application comprises the following steps:

preparation of agent A:

adding the mixed alkali into water, and stirring at a rotating speed of 60-500 RPM until the mixed alkali is uniform;

adding methacryloyloxyethyl trimethyl ammonium chloride and stirring uniformly;

adding bentonite and stirring until the bentonite is fully swelled to obtain a solution I;

adding polyaluminium chloride into water, and stirring at a rotating speed of 60-500 RPM until the mixture is uniform to obtain a solution II;

adding the first solution into the second solution, and uniformly stirring to obtain an agent A;

preparation of the agent B:

and sequentially adding phytic acid, alum, starch, an oxidant and cationic polyacrylamide into water, and stirring to completely dissolve the components, thereby obtaining the agent B.

The preparation method of the paint mist coagulant provided by the embodiment of the application has at least the following beneficial effects: the paint mist coagulant prepared by the method can treat water paint wastewater, oily paint wastewater and wastewater mixed by the water paint wastewater and the oily paint wastewater, the application range of the paint mist coagulant is improved, and simultaneously, two functional formulas of phytic acid and an oxidant are added into the agent B, so that the paint mist coagulant has the effects of deodorization and scale removal, the treated water can be recycled for a long time, and the scaling of a pipeline can be prevented.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Detailed Description

The following detailed description of the embodiments of the application is merely illustrative of the application and is not to be construed as limiting the application. The equipment and reagents used in the present application are conventional commercially available products in the art, unless specifically indicated.

In the description of the present application, a number means one or more, a number means two or more, and greater than, less than, exceeding, etc. are understood to not include the present number, and above, below, within, etc. are understood to include the present number. The description of the first and second is for the purpose of distinguishing between technical features only and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

The embodiment of the first aspect of the application provides a paint mist coagulant, which comprises an agent A and an agent B, wherein the agent A comprises the following components in percentage by mass: 3 to 8 percent of polyaluminum chloride, 0.2 to 1 percent of bentonite, 0.1 to 0.5 percent of methacryloxyethyl trimethyl ammonium chloride, 0.2 to 1 percent of mixed alkali and the balance of water; the component and mass ratio of the agent B are as follows: 0.05 to 0.5 percent of phytic acid, 0.05 to 0.5 percent of alum, 0.05 to 0.5 percent of starch, 0.3 to 0.6 percent of cationic polyacrylamide, 0.05 to 0.5 percent of oxidant and the balance of water.

The paint mist coagulant provided by the application can treat water paint wastewater, oily paint wastewater and wastewater mixed by the water paint wastewater and the oily paint wastewater, the application range of the paint mist coagulant is improved, and simultaneously, two functional formulas of phytic acid and an oxidant are added into the agent B, so that the paint mist coagulant has the effects of deodorization and scale removal, the treated water can be recycled for a long time, and the scaling of a pipeline can be prevented.

The agent A adopts bentonite and polyaluminium chloride as flocculating agents, so that paint mist particles in the wastewater can be gathered and enlarged, and the paint mist particles gradually form flocs and are separated from water, thereby realizing the effect of wastewater purification. And polyaluminium chloride and bentonite are universal flocculating agents, and can simultaneously purify water-based or oil-based paint wastewater. The methacryloxyethyl trimethyl ammonium chloride plays a role in dispersing in the agent A, and bentonite which is easy to settle can be fully dispersed in water.

When the paint mist coagulant is used for treating wastewater, the ratio of the agent A to the wastewater is 0.2%, the ratio of the agent B to the wastewater is 0.3%, and the dosage of the agent accounts for 0.5% of the total wastewater.

In some embodiments of the present application, the mixed base in agent a is a mixture of one or more of sodium hydroxide, triethanolamine, and potassium silicate, and may be a mixture of any two or three.

When the mixed alkali is a mixture of three kinds of sodium hydroxide, triethanolamine and potassium silicate, the mixing ratio may be 1: (0.5-1): (0.5-1), and the mixing ratio can be 1:1:1, 1:0.5:0.5 or 1:1:0.5.

The agent A uses sodium hydroxide, triethanolamine and potassium silicate as mixed alkali, and the mixed alkali can adjust the pH value (hydrogen ion concentration index) of the agent A, so that the pH value for triggering flocculation reaction can be reached when the agent A is added into water, and flocculation reaction can occur rapidly. It should be noted that the sodium hydroxide, the triethanolamine and the potassium silicate may be mixed in other mixing ratios, and may be determined according to practical situations, and are not particularly limited herein.

In some embodiments of the application, the oxidizing agent in agent B is one of potassium persulfate and potassium persulfate, or a mixture of both. The oxidant may be a mixture of potassium persulfate and potassium persulfate, and the mixing ratio is 1: (0.8-1.2), such as 1:0.8, 1:1 or 1:1.2.

It should be noted that potassium persulfate and potassium persulfate are activated by the influence of trace metal ions in water, so that the wastewater has an oxidation effect, organic pollutants dissolved in the wastewater can be degraded, and the treated wastewater can be continuously used and does not become odorous after the organic pollutants in the wastewater are degraded. The wastewater purification and recycling process can be generally continued for more than three months, and the purified water can be ensured not to become smelly in the recycling process by adding the oxidant into the agent B.

It should be noted that the phytic acid in the component of the agent B is a high-efficiency scale remover, and can dissolve scale in the recycled water conveying pipeline, so that the pipeline can be ensured to be clean and unobstructed.

It is also noted that the starch, alum and cationic polyacrylamide added into the agent B can further agglomerate the flocs generated after the agent A is added, larger flocs are formed, and the large flocs can obtain excellent floating performance after being wrapped with gas.

The preparation method of the paint mist coagulant provided by the embodiment of the second aspect of the application comprises the preparation of the agent A and the preparation of the agent B.

The preparation method of the agent A comprises the following steps: firstly adding mixed alkali into water and stirring uniformly, then adding methacryloxyethyl trimethyl ammonium chloride and stirring uniformly, adding bentonite and stirring until the bentonite is fully swelled, so as to obtain a solution I. After the bentonite is added, stirring can be continued for 2-3 hours to fully swell the bentonite, for example, the bentonite can be stirred for 2 hours or 3 hours, and the bentonite can be fully swelled according to actual conditions.

And adding the polyaluminium chloride into water and uniformly stirring to obtain a solution II.

Slowly adding the first solution into the second solution, and stirring uniformly to obtain the agent A.

It should be noted that, the solution one is slowly added into the solution two, so that the pH value of the agent a can be guaranteed to be slowly raised and stabilized at a proper value, so that the agent a is not easy to solidify.

In the preparation process of the agent A, the mixed alkali is added into water and stirred at a rotating speed of 60-500 RPM, for example, 60RPM, 100RPM, 200RPM or 500RPM, which can be determined according to practical situations, and the method is not particularly limited herein.

In the preparation process of the agent A, the polyaluminum chloride is added into water and stirred at a rotating speed of 60-500 RPM, for example, 60RPM, 100RPM or 500RPM, which can be determined according to practical situations, and the method is not particularly limited.

The preparation step of the agent B comprises the following steps: the phytic acid, alum, starch, oxidant and cationic polyacrylamide are added to water in sequence, and these materials are completely dissolved while stirring, thereby obtaining the agent B.

The paint mist coagulant prepared by the method can treat water paint wastewater, oily paint wastewater and wastewater mixed by the water paint wastewater and the oily paint wastewater, the application range of the paint mist coagulant is improved, and simultaneously, the agent B is added with two functional formulas of phytic acid and an oxidant, so that the paint mist coagulant has the effects of deodorization and scale removal, the treated water can be recycled for a long time, and the pipeline scaling can be prevented.

In some embodiments of the application, the agent A and the agent B are respectively taken and added into water paint wastewater, oily paint wastewater and mixed wastewater with the same turbidity, the addition amount of the paint mist coagulant is 5 per mill of the wastewater, the paint mist coagulant is stirred uniformly, the paint mist coagulant is left to stand, after surface scum is removed, a water sample with the depth of 5cm below the water surface is taken, the turbidity of the water sample is tested, and the turbidity test method is referred to HJ 1075-2019 'turbidity determination turbidimeter method of water quality'.

Embodiment one:

the paint mist coagulant comprises an agent A and an agent B.

The component and mass ratio of the agent A are as follows: 6% of polyaluminum chloride, 0.3% of bentonite, 0.3% of methacryloyloxyethyl trimethyl ammonium chloride, 0.5% of mixed alkali and the balance of water. Wherein the mixed alkali is a mixture of three of sodium hydroxide, triethanolamine and potassium silicate according to a ratio of 1:1:1.

The component and mass ratio of the agent B are as follows: 0.05% of phytic acid, 0.2% of alum, 0.2% of starch, 0.4% of cationic polyacrylamide, 0.5% of oxidant and the balance of water.

The preparation method of the paint mist coagulant comprises the following steps:

preparation of agent A: step 1: adding the mixed alkali into water, stirring at a rotating speed of 60-500 rpm, then sequentially adding methacryloxyethyl trimethyl ammonium chloride and bentonite under stirring, and continuing stirring for 2 hours until the bentonite is fully swelled, wherein the solution is marked as a solution I;

step 2: adding polyaluminium chloride into water, stirring at a speed of 60-500 rpm, and marking the solution as a solution II;

step 3: slowly adding the first solution into the second solution, and continuously stirring uniformly at the rotation speed of 60-500 rpm to obtain the agent A.

Preparation of the agent B: and adding phytic acid, alum, starch, an oxidant and cationic polyacrylamide into water in sequence while stirring, and stirring to completely dissolve the components to obtain the agent B.

Embodiment two:

the difference from example 1 is that in this example, no polyaluminum chloride was added to the agent A.

Embodiment III:

the only difference from example 1 is that in this example, no bentonite was added to the agent a.

Embodiment four:

the difference from example 1 is that in this example, methacryloyloxyethyl trimethyl ammonium chloride was not added to agent A.

Fifth embodiment:

the difference from example 1 is that in this example, no mixed alkali was added to the agent A.

The paint mist coagulant prepared in the above examples one to five was added to 3 kinds of wastewater, namely, aqueous paint wastewater, oily paint wastewater and mixed wastewater thereof, respectively, and turbidity was measured. The turbidity removal rates are shown in table 1:

table 1 turbidity removal rates obtained in each embodiment

From the table, the water sample treated by the formula of the embodiment can obtain high turbidity removal rate, and the purification effects of the water paint wastewater, the paint wastewater and the mixed wastewater are good, so that the purification requirement is met.

In the second example, compared with the first example, the turbidity removal rate of the treated wastewater is obviously lower, and the wastewater is very turbid, so that the polyaluminium chloride plays a main flocculation role in the formula of the agent A.

In example three, compared with example one, bentonite is absent, the turbidity removal rate of the treated wastewater is reduced, and the bentonite plays an auxiliary flocculation role in the agent A formula.

In example four, compared with example one, the turbidity removal rate of the treated wastewater is reduced due to the lack of the methacryloyloxyethyl trimethyl ammonium chloride, which shows that the methacryloyloxyethyl trimethyl ammonium chloride is used as a surfactant in the formula of the agent A to promote the wastewater purification.

Compared with the first embodiment, the fifth embodiment lacks mixed alkali, the turbidity removal rate of the treated wastewater is low, and the wastewater is turbid, because the mixed alkali can adjust the pH value of the wastewater to be in the reaction range of the flocculant, thereby realizing the efficient purification effect.

Example six:

the only difference from example one is that in this example the mixed base is a 1:1 mixture of triethanolamine and potassium silicate.

Embodiment seven:

the only difference from example one is that in this example the mixed base is a 1:1 mixture of sodium hydroxide and potassium silicate.

Example eight:

the only difference from example one is that in this example the mixed base is a 1:1 mixture of sodium hydroxide and triethanolamine.

Example nine:

the only difference from example one is that in this example the mixed base is replaced by a single sodium hydroxide.

Example ten:

the only difference from example one is that in this example the mixed base is replaced by a single triethanolamine.

Example eleven:

the only difference from example one is that in this example the mixed base is replaced by a single potassium silicate.

The paint mist coagulant prepared in the above examples one and six to eleventh was added to 3 kinds of wastewater, namely, water-based paint wastewater, oil-based paint wastewater and mixed wastewater thereof, respectively, and turbidity was measured. Turbidity removal rates are shown in table 2:

table 2 turbidity removal rates obtained in the respective embodiments

From Table 2, it can be seen that the water sample is cleaner by using a mixture of three bases of sodium hydroxide, triethanolamine and potassium silicate as the pH adjustor, as seen from turbidity removal rate, by replacing the three mixed bases of example one with two or one.

It should be noted that when the mixed alkali is one of sodium hydroxide, triethanolamine and potassium silicate, or a mixture of any two, the turbidity removal rate of the wastewater can be at a high level.

Embodiment twelve:

the difference from the first example is that in this example, no phytic acid was added to the B agent.

Embodiment thirteen:

the only difference from the first example is that alum was not added to the agent B in this example.

Fourteen examples:

the difference from example one is that in this example, no starch was added to the agent B.

Example fifteen:

the difference from the first example is that in this example, no cationic polyacrylamide was added to the agent B.

Example sixteen:

the difference from the first embodiment is that in this embodiment, no oxidizing agent is added to the agent B.

The paint mist coagulant prepared in the first and twelve examples to sixteen examples was added to 3 kinds of wastewater, namely, water paint wastewater, oil paint wastewater and mixed wastewater of the two, respectively, and turbidity was measured. The turbidity removal rates are shown in table 3:

table 3 turbidity removal rates obtained in the respective embodiments

As can be seen from table 3, examples twelve and sixteen comparative examples one lack the scale remover phytic acid and the oxidizing agent, respectively, and the turbidity removal rates were approximately similar, indicating that phytic acid and the oxidizing agent were functional in the formulation, i.e., provided the scale removal and oxidative deodorization.

Examples thirteen and fourteen comparative examples-in the absence of alum and starch, respectively, the turbidity removal was significantly reduced, indicating that alum and starch act to assist in the coacervation in the formulation.

Example fifteen lacks the cationic polyacrylamide compared to example one, and the turbidity removal rate is greatly reduced, indicating that the cationic polyacrylamide plays a major role in the formulation.

The embodiments of the present application have been described in detail with reference to the table data, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge of one of ordinary skill in the art without departing from the spirit of the present application.

Claims (6)

1. A paint mist coagulant, comprising:

the agent A and the agent B are mixed,

the agent A comprises the following components in percentage by mass: 3 to 8 percent of polyaluminum chloride, 0.2 to 1 percent of bentonite, 0.1 to 0.5 percent of methacryloxyethyl trimethyl ammonium chloride, 0.2 to 1 percent of mixed alkali and the balance of water;

the agent B comprises the following components in percentage by mass: 0.05 to 0.5 percent of phytic acid, 0.05 to 0.5 percent of alum, 0.05 to 0.5 percent of starch, 0.3 to 0.6 percent of cationic polyacrylamide, 0.05 to 0.5 percent of oxidant and the balance of water.

2. The paint mist coagulant as recited in claim 1, wherein the mixed alkali is a mixture of any one or more of sodium hydroxide, triethanolamine and potassium silicate.

3. The paint mist coagulant as recited in claim 2, wherein the mixed alkali is a mixture of the sodium hydroxide, the triethanolamine and the potassium silicate, and a mixing ratio of the three is 1: (0.5-1): (0.5-1).

4. The paint mist coagulant of claim 1, wherein the oxidizing agent is one or a mixture of two of potassium persulfate and potassium persulfate.

5. A paint mist coagulant as set forth in claim 1 wherein the oxidizing agent is a mixture of potassium persulfate and potassium persulfate in a mixing ratio of 1: (0.8-1.2).

6. The preparation method of the paint mist coagulant is characterized by comprising the following steps:

preparation of agent A:

adding the mixed alkali into water, and stirring at a rotating speed of 60-500 RPM until the mixed alkali is uniform;

adding methacryloyloxyethyl trimethyl ammonium chloride and stirring uniformly;

adding bentonite and stirring until the bentonite is fully swelled to obtain a solution I;

adding polyaluminium chloride into water, and stirring at a rotating speed of 60-500 RPM until the mixture is uniform to obtain a solution II;

adding the first solution into the second solution, and uniformly stirring to obtain an agent A;

preparation of the agent B:

and adding phytic acid, alum, starch, an oxidant and cationic polyacrylamide into water in sequence, and stirring until the phytic acid, the alum, the starch, the oxidant and the cationic polyacrylamide are completely dissolved, so that the agent B is obtained.