A pretreatment agent for wastewater before entering an evaporator and a preparation method thereof

Abstract

The invention discloses a pretreatment agent for wastewater before it enters an evaporator and a preparation method thereof. The pretreatment agent comprises an A component, a B component and a C component. During the pretreatment process, polyaluminium chloride and polyferric sulfate in the B component can form a complex with polyacrylamide in the C component, can adsorb and entangle impurities in the wastewater, can remove the impurities by forming a complex, can improve the removal capacity, and solves the defect of insufficient purification capacity of the pretreatment agent for the wastewater evaporator in the prior art; the rare earth modifier is polyaluminium ferric silicate, and the polyaluminium ferric silicate is modified by lanthanum and cerium, and the lanthanum and cerium can improve the charge distribution of the pretreatment agent, so that the charge density in the pretreatment process is increased, so that the complex formed by the pretreatment agent can adsorb more impurities according to the action of electrostatic force, thereby improving the adsorption capacity and enhancing the impurity removal effect of the pretreatment agent.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, in particular to a pretreatment agent for wastewater before it enters an evaporator and a preparation method thereof. Background Art

[0002] Wastewater treatment, also known as sewage treatment, refers to the process of removing pollutants from wastewater containing pollutants, such as domestic sewage, industrial wastewater, agricultural wastewater, etc., through a series of physical, chemical or biological treatment processes to make the water quality meet the discharge standards or reuse water quality requirements.

[0003] Wastewater often contains a large amount of valuable substances, such as organic matter, inorganic salts, heavy metals, etc. By using evaporators to treat wastewater, concentrate and purify wastewater, these substances can be recycled and the efficiency of resource utilization can be improved. The water in the wastewater is evaporated into water vapor through the heating effect of the evaporator, thereby achieving the concentration and purification of the wastewater.

[0004] Before using the evaporator for wastewater treatment, pretreatment is required. Evaporator pretreatment refers to the removal of impurities such as suspended matter, sediment, and organic matter in the wastewater to reduce the risk of blockage and contamination of the evaporator. Currently, evaporator pretreatment mainly uses chemicals to remove impurities, but the removal rate is low and impurities are easily left, which makes the evaporator at risk of failure.

[0005] Therefore, it is necessary to improve the wastewater evaporator pretreatment reagents in daily life to solve the above-mentioned defects. Summary of the invention

[0006] The present invention overcomes the deficiencies of the prior art and provides a pretreatment agent for wastewater before it enters an evaporator and a preparation method thereof, aiming to solve the defect of insufficient purification capacity of the pretreatment agent for wastewater evaporator in the prior art.

[0007] To achieve the above object, the technical solution adopted by the present invention is: a pretreatment agent for wastewater before entering the evaporator, composed of component A, component B and component C, wherein:

[0008] The A component includes potassium bicarbonate and sodium carbonate, and the mass ratio between the potassium bicarbonate and the sodium carbonate is 1:2;

[0009] The B component includes polyaluminium chloride, polyferric sulfate and a rare earth modifier, the mass ratio of the polyaluminium chloride to the polyferric sulfate is 3:1, and the rare earth modifier accounts for 10-20% of the total mass of the polyaluminium chloride and the polyferric sulfate;

[0010] The C component is polyacrylamide;

[0011] The mass ratio of the A component, the B component and the C component is 1:10-12:15-20.

[0012] In a preferred embodiment of the present invention, the ratio between the pretreatment agent and the wastewater is based on the COD concentration of the wastewater, and the amount of the pretreatment agent added is 2-3% of the COD concentration of the wastewater.

[0013] In a preferred embodiment of the present invention, the rare earth modifier is polyaluminum ferric silicate, and the polyaluminum ferric silicate is modified with lanthanum and cerium.

[0014] In a preferred embodiment of the present invention, the lanthanum and the cerium account for 0.35%-0.45% and 0.05%-0.15% of the mass of the polysilicate aluminum ferrocene, respectively.

[0015] In a preferred embodiment of the present invention, the C component contains nano-alumina and nano-zirconia, the particle sizes of the nano-alumina and nano-zirconia are both less than 50nm, the mass ratio between the nano-alumina and nano-zirconia is 3:1, and the total mass of the nano-alumina and nano-zirconia accounts for 20-30% of the mass of the polyacrylamide.

[0016] In a preferred embodiment of the present invention, the C component contains chitosan, and the mass of the chitosan accounts for 10-15% of the C component.

[0017] To achieve the above object, the second technical solution adopted by the present invention is: a method for preparing a pretreatment agent for wastewater before it enters an evaporator, comprising the following steps:

[0018] S1: mixing potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain a component A;

[0019] S2: mixing polyferric sulfate, polyaluminium chloride and rare earth modifier in a ratio of 5:15:2-4 to obtain a component B material;

[0020] S3: using polyacrylamide as the C component material;

[0021] S4: adding the component A material, the component B material and the component C material to a 30% hydrogen peroxide solution at a mass ratio of 1:10-12:15-20, respectively, and the mass ratio of the total mass of the component A material, the component B material and the component C material to the hydrogen peroxide solution is 1:5-10, to obtain a pretreatment solution;

[0022] S5: drying the pretreatment solution at a temperature of 60-80° C. for 3-4 hours to obtain a pretreatment agent for wastewater before it enters an evaporator.

[0023] In a preferred embodiment of the present invention, the C component material contains titanium dioxide, and the mass ratio of the titanium dioxide to the polyacrylamide is 1:10-20.

[0024] In a preferred embodiment of the present invention, in S4, the component A material, the component B material and the component C material are added to the hydrogen peroxide solution in sequence.

[0025] In a preferred embodiment of the present invention, the hydrogen peroxide solution contains ozone, and the mass ratio of the hydrogen peroxide to the ozone is 1:1-2.

[0026] The present invention solves the defects existing in the background technology and has the following beneficial effects:

[0027] (1) The present invention provides a pretreatment agent for wastewater before it enters an evaporator, comprising a component A, a component B and a component C. During the pretreatment process, the polyaluminium chloride and the polyferric sulfate in the component B can form a complex with the polyacrylamide in the component C, and can adsorb and entangle impurities in the wastewater. Compared with the wastewater pretreatment agent in the prior art, the impurities can be removed by forming a complex, and the removal capacity can be improved, thereby solving the defect of insufficient purification capacity of the wastewater evaporator pretreatment agent in the prior art.

[0028] (2) In the present invention, the rare earth modifier is polyaluminum ferric silicate, which is modified by lanthanum and cerium. Lanthanum and cerium can improve the charge distribution of the pretreatment agent, thereby increasing the charge density during the pretreatment process. Compared with the prior art, the charge distribution can be improved by lanthanum and cerium, so that the complex formed by the pretreatment agent can adsorb more impurities according to the action of electrostatic force, thereby improving the adsorption capacity and enhancing the impurity removal effect of the pretreatment agent.

[0029] (3) In the present invention, component C contains nano-alumina and nano-zirconia, and the particle size of nano-alumina and nano-zirconia is less than 50nm. Nanomaterials have stronger adsorption capacity due to their high specific surface area and high porosity. Compared with the prior art, the adsorption effect of impurities in wastewater is significantly improved, and they can be used as an auxiliary component of the flocculant to increase the strength and stability of the flocculants, thereby improving the flocculation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 It is a method step diagram of a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0034] A pretreatment agent for wastewater before it enters an evaporator, comprising component A, component B and component C, wherein:

[0035] Component A includes potassium bicarbonate and sodium carbonate, and the mass ratio between potassium bicarbonate and sodium carbonate is 1:2;

[0036] Component B includes polyaluminium chloride, polyferric sulfate and rare earth modifier, the mass ratio between polyaluminium chloride and polyferric sulfate is 3:1, and the rare earth modifier accounts for 10-20% of the total mass of polyaluminium chloride and polyferric sulfate. The aluminium ions and iron ions in PAC and PFS will be partially hydrolyzed to form positively charged hydroxyaluminium ions and hydroxyferric ions. These ions have a high positive charge density and can strongly attract negatively charged colloidal particles and suspended matter in wastewater.

[0037] Component C is polyacrylamide. Components B and C have different functional groups and adsorption sites, which can adsorb pollutants of different types and properties in wastewater. When used in combination, these adsorption sites work together to improve the removal efficiency of multiple pollutants in wastewater.

[0038] Component B is an inorganic flocculant, and component C is an organic flocculant. When the inorganic flocculant and the organic coagulant are used together, the structure and stability of the flocs can be further increased. As high molecular polymers, the inorganic flocculants and organic flocculants can form a more complex and stable network structure through their long chain molecules and the flocs formed by the inorganic flocculants. This network structure can not only increase the density and strength of the flocs, but also enhance its ability to capture and remove pollutants.

[0039] The mass ratio of component A, component B and component C is 1:10-12:15-20.

[0040] A pretreatment agent for wastewater before it enters an evaporator comprises component A, component B and component C. During the pretreatment process, polyaluminium chloride and polyferric sulfate in component B can form a complex with polyacrylamide in component C, can adsorb and entangle impurities in the wastewater, can remove the impurities by forming a complex, can improve the removal capacity, and solves the defect of insufficient purification capacity of the wastewater evaporator pretreatment agent in the prior art.

[0041] The ratio between pretreatment agent and wastewater is based on the COD concentration of the wastewater, and the amount of pretreatment agent added is 2-3% of the COD concentration of the wastewater. By determining the amount of agent added according to the COD concentration of the wastewater, the amount of agent used can be adjusted more accurately to ensure that the amount of agent used is neither too much nor too little, thereby improving the treatment effect.

[0042] The rare earth modifier is polysilicate aluminum iron, which is modified by lanthanum and cerium. The polysilicate aluminum iron, lanthanum solution and cerium solution are mixed together in water. The lanthanum solution can be lanthanum chloride, and the cerium solution can be cerium nitrate. The ions of lanthanum and cerium will react chemically with the silicate, aluminum ions and iron ions in the polysilicate aluminum iron to form chemical bonds. Lanthanum and cerium can improve the charge distribution of the pretreatment agent, increase the charge density during the pretreatment process, and improve the charge distribution through lanthanum and cerium, so that the complex formed by the pretreatment agent can adsorb more impurities according to the action of electrostatic force, improve the adsorption capacity, and enhance the impurity removal effect of the pretreatment agent. In the floc structure formed by the inorganic flocculant, the presence of rare earth elements can serve as a cross-linking point to increase the connection strength inside the floc, making it more compact and stable. This improved floc structure helps to improve the sedimentation rate and dehydration performance of the floc.

[0043] Lanthanum and cerium account for 0.35%-0.45% and 0.05%-0.15% of the mass of polysilicate aluminum ferric, respectively. The addition of lanthanum and cerium will enhance the complexing ability of polysilicate aluminum ferric with impurities in wastewater, making the formed complex more stable, thereby improving the adsorption and removal effect of impurities in wastewater. The addition of lanthanum and cerium will improve the flocculation effect of polysilicate aluminum ferric, help the aggregation and sedimentation of suspended particles in wastewater, thereby improving the efficiency of wastewater treatment. The addition of lanthanum and cerium will improve the chemical stability of polysilicate aluminum ferric, making it more resistant to acid, alkali and redox environments during wastewater treatment, thereby extending its service life and ensuring the stability of the impurity removal effect.

[0044] Component C contains nano-alumina and nano-zirconia, the particle size of which is less than 50nm, the mass ratio of which is 3:1, and the total mass of which accounts for 20-30% of the total mass of polyacrylamide. Nanomaterials have stronger adsorption capacity due to their high specific surface area and high porosity. The addition of nano-alumina and nano-zirconia can significantly improve the adsorption effect of impurities in wastewater. Nanomaterials can be used as auxiliary components of flocculants to increase the strength and stability of flocs, thereby improving the flocculation effect and promoting the aggregation and sedimentation of suspended particles in wastewater.

[0045] Component C contains chitosan, which accounts for 10-15% of the C component. Chitosan has good biocompatibility and biodegradability, and has little impact on the environment during wastewater treatment. Chitosan contains amino groups, which can form stable complexes with heavy metal ions and effectively adsorb and remove heavy metal ions in wastewater.

[0046] like Figure 1 As shown, in order to achieve the above-mentioned purpose, the second set of technical solutions adopted by the present invention is: a method for preparing a pretreatment agent for wastewater before it enters an evaporator, comprising the following steps:

[0047] S1: mixing potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain a component A;

[0048] S2: mixing polyferric sulfate, polyaluminium chloride and rare earth modifier in a ratio of 5:15:2-4 to obtain a component B material;

[0049] S3: using polyacrylamide as the C component material;

[0050] S4: adding the component A substance, the component B substance and the component C substance to a 30% hydrogen peroxide solution at a mass ratio of 1:10-12:15-20, respectively, and the mass ratio of the total mass of the component A substance, the component B substance and the component C substance to the hydrogen peroxide solution is 1:5-10, to obtain a pretreatment solution;

[0051] S5: drying the pretreatment solution at a temperature of 60-80° C. for 3-4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0052] Premixed reagents have better chemical stability and reduce decomposition or precipitation during storage and transportation. Premixing can reduce side reactions during wastewater treatment, avoiding unnecessary chemical consumption and the generation of pollutants.

[0053] Component C contains titanium dioxide, and the mass ratio of titanium dioxide to polyacrylamide is 1:10-20. Titanium dioxide is a photocatalytic material, which can produce strong oxidizing hydroxyl radicals, especially under ultraviolet light, which helps to degrade organic pollutants in wastewater. Titanium dioxide has a large specific surface area and porosity, which can provide additional adsorption sites and enhance the adsorption capacity of pollutants in wastewater.

[0054] In S4, component A, component B and component C are added to the hydrogen peroxide solution in sequence. Since the dissolution process of component A is relatively mild and has little effect on the components added subsequently, it can be added first. This allows component A to be initially dissolved and dispersed in the hydrogen peroxide solution. Polyferric sulfate, polyaluminium chloride and the like in component B form colloids or precipitates in water, which can serve as the core of subsequent flocculation. Adding component B after component A has been initially dissolved is conducive to the uniform distribution of component B in the solution and the formation of colloids / precipitates. Component C is a high molecular polymer with good flocculation properties. After component A and component B have been added and initially reacted, component C is added, and the colloids / precipitates formed by component A and component B can be further flocculated into larger particles by using the flocculation properties of component C.

[0055] The hydrogen peroxide solution contains ozone, and the mass ratio of hydrogen peroxide to ozone is 1:1-2. Ozone is a very strong oxidant, and combined with hydrogen peroxide, it can provide stronger oxidizing ability and help decompose difficult-to-degrade organic pollutants in wastewater.

[0056] By mixing the three components A, B, and C in proportion and adding them to a hydrogen peroxide solution, and then drying them, a solid pretreatment agent is prepared. This solid agent is more stable during storage and transportation, and is not prone to stratification or chemical reactions between components, ensuring that each component can act on the wastewater evenly and consistently when the agent is used, thereby improving the consistency of the treatment effect. The coagulants such as polyferric sulfate and polyaluminum chloride in the B component and the polyacrylamide flocculant in the C component form a more effective coagulation and flocculation system in the hydrogen peroxide solution. This system can form flocs and settle more quickly in wastewater treatment, improving the efficiency of removing suspended matter and colloidal pollutants, while directly adding the A, B, and C components to the wastewater will cause the generation of by-products, thereby reducing the flocculation effect. The three components A, B, and C are mixed in proportion and added to the hydrogen peroxide solution, and then dried to ensure the compactness of the floccules when the agent contacts and reacts with the wastewater, while directly adding the A, B, and C components to the wastewater will cause the temperature in the reaction process to destroy the flocculation structure and affect the adsorption effect.

[0057] When the present invention is used, a pretreatment agent is added into the wastewater, and the amount of the pretreatment agent added is 2-3% of the COD concentration of the wastewater. During the process of adding the pretreatment agent, an ultraviolet lamp is used for irradiation. During the irradiation process of the ultraviolet lamp, the titanium dioxide in the pretreatment agent can be catalyzed, so that the titanium dioxide catalyzes and oxidizes organic matter in the wastewater, and decomposes and adsorbs the organic matter in the wastewater.

[0058] Embodiment 1

[0059] This embodiment prepares a pretreatment agent for wastewater before it enters the evaporator. The preparation process is as follows:

[0060] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0061] S2: Mixing polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum, wherein lanthanum accounts for 0.5% of the mass of the polyaluminium ferrosilicate, to obtain a B component substance.

[0062] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 20% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0063] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0064] S5: drying the pretreatment solution at a temperature of 80° C. for 4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0065] Embodiment 2

[0066] This embodiment prepares a pretreatment agent for wastewater before it enters the evaporator. The preparation process is as follows:

[0067] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0068] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.45% and 0.05% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0069] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 20% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0070] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0071] S5: drying the pretreatment solution at a temperature of 80° C. for 4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0072] Embodiment 3

[0073] This embodiment prepares a pretreatment agent for wastewater before it enters the evaporator. The preparation process is as follows:

[0074] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0075] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.4% and 0.1% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0076] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 20% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0077] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0078] S5: drying the pretreatment solution at a temperature of 80° C. for 4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0079] Embodiment 4

[0080] This embodiment prepares a pretreatment agent for wastewater before it enters the evaporator. The preparation process is as follows:

[0081] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0082] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.35% and 0.15% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0083] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 20% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0084] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0085] S5: drying the pretreatment solution at a temperature of 80° C. for 4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0086] Embodiment 5

[0087] This embodiment prepares a pretreatment agent for wastewater before it enters the evaporator. The preparation process is as follows:

[0088] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0089] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.3% and 0.2% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0090] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 20% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0091] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0092] S5: drying the pretreatment solution at a temperature of 80° C. for 4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0093] Embodiment 6

[0094] This embodiment prepares a pretreatment agent for wastewater before it enters the evaporator. The preparation process is as follows:

[0095] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0096] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.4% and 0.1% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0097] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 15% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0098] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0099] S5: drying the pretreatment solution at a temperature of 80° C. for 4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0100] Embodiment 7

[0101] This embodiment prepares a pretreatment agent for wastewater before it enters the evaporator. The preparation process is as follows:

[0102] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0103] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.4% and 0.1% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0104] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 25% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0105] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0106] S5: drying the pretreatment solution at a temperature of 80° C. for 4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0107] Embodiment 8

[0108] This embodiment prepares a pretreatment agent for wastewater before it enters the evaporator. The preparation process is as follows:

[0109] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0110] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.4% and 0.1% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0111] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 30% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0112] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0113] S5: drying the pretreatment solution at a temperature of 80° C. for 4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0114] Embodiment 9

[0115] This embodiment prepares a pretreatment agent for wastewater before it enters the evaporator. The preparation process is as follows:

[0116] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0117] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.4% and 0.1% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0118] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 35% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0119] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0120] S5: drying the pretreatment solution at a temperature of 80° C. for 4 hours to obtain a pretreatment agent for the wastewater before it enters the evaporator.

[0121] Comparative Example 1

[0122] This embodiment prepares a wastewater pretreatment agent, and the preparation process is as follows:

[0123] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0124] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate to obtain a B component material.

[0125] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 25% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0126] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0127] S5: drying the pretreated solution at a temperature of 80° C. for a drying time of 4 hours to obtain a wastewater treatment agent.

[0128] Comparative Example 2

[0129] This embodiment prepares a wastewater treatment agent, and the preparation process is as follows:

[0130] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0131] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.4% and 0.1% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0132] S3: polyacrylamide, chitosan and titanium dioxide are mixed together, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide and titanium dioxide, to obtain a C component substance.

[0133] S4: Adding component A, component B and component C in a mass ratio of 1:10:15 to a 30% hydrogen peroxide solution in sequence, wherein the hydrogen peroxide solution contains ozone, the mass ratio of hydrogen peroxide to ozone in the hydrogen peroxide solution is 1:1, and the mass ratio of the total mass of component A, component B and component C to the hydrogen peroxide solution is 1:10, to obtain a pretreatment solution.

[0134] S5: drying the pretreated solution at a temperature of 80° C. for 4 hours to obtain a wastewater treatment agent.

[0135] Comparative Example 3

[0136] This comparative example is a wastewater pretreatment agent, and the preparation method is as follows:

[0137] S1: Mix potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain component A.

[0138] S2: Mix polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified with lanthanum and cerium, wherein lanthanum and cerium account for 0.4% and 0.1% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B substance.

[0139] S3: Mix polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide together, wherein the particle sizes of nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of nano-alumina and nano-zirconia is 3:1, the total mass of nano-alumina and nano-zirconia accounts for 25% of the mass of polyacrylamide, the mass ratio of titanium dioxide to polyacrylamide is 1:10, and the mass of chitosan accounts for 10% of the total mass of polyacrylamide, nano-alumina, nano-zirconia and titanium dioxide, to obtain component C.

[0140] S4: Mix the component A material, the component B material and the component C material in a mass ratio of 1:10:15 to obtain a wastewater treatment agent.

[0141] The same weight of the treatment reagents in Examples 1 to 9 and Comparative Examples 1 to 3 were added to the same volume of wastewater. After standing for 1 hour under ultraviolet irradiation, the solutions were respectively subjected to turbidity detection and organic matter content detection. The turbidity detection method was a turbidity detector to obtain a turbidity value. The organic matter content was detected using a potassium dichromate method to obtain the wastewater oxygen demand. The turbidity value and the wastewater oxygen demand are shown in Table 1:

[0142] Table 1 Experimental data of turbidity value and wastewater oxygen demand in Examples 1 to 9 and Comparative Examples 1 to 3

[0143] Sample source Turbidity value (NTU) Wastewater oxygen demand (mg / L) Embodiment 1 5.0 2597 Embodiment 2 3.3 2432 Embodiment 3 2.7 2213 Embodiment 4 3.1 2376 Embodiment 5 4.7 2461 Embodiment 6 4.3 2298 Embodiment 7 1.8 2014 Embodiment 8 2.5 2107 Embodiment 9 4.9 2238 Comparative Example 1 12.5 3219 Comparative Example 2 13.4 3321 Comparative Example 3 9.5 2836

[0144] As can be seen from Table 1, the turbidity values ​​and wastewater oxygen demand in Examples 1 to 9 are lower than those in Comparative Examples 1 to 3, indicating that the modification of polysilicate aluminum iron with lanthanum and cerium and the addition of nano-alumina and nano-zirconium oxide can effectively promote the pretreatment effect of wastewater before entering the evaporator.

[0145] In Examples 1 to 5, as the mass proportion of lanthanum and cerium in polysilicate aluminum ferric increases, the turbidity value and the oxygen demand of the wastewater first decrease and then increase. Lanthanum and cerium can enhance the flocculation performance of polysilicate aluminum ferric, which helps to remove suspended solids and organic matter in the wastewater, thereby reducing turbidity and COD. However, when the proportion of lanthanum is too low, the stability of the flocculent body is reduced and the adsorption capacity for impurities is weakened. The best embodiment is Example 3.

[0146] In Example 3 and Examples 6 to 9, as the total mass ratio of nano-alumina and nano-zirconium oxide to the mass ratio of polyacrylamide gradually increases, the turbidity value and the oxygen demand of the wastewater first decrease and then increase. The nanoparticles act as flocculation nuclei, promote the formation and growth of flocs, and improve the flocculation efficiency. As their ratio to polyacrylamide increases, they help to form larger flocs, accelerate the sedimentation process, and improve the pretreatment effect. However, an excessively high mass ratio causes the floc structure to be too loose, reduces the sedimentation efficiency, and causes an increase in the turbidity value and the oxygen demand of the wastewater. The best embodiment is Example 7.

[0147] The turbidity value and wastewater oxygen demand in Example 7 are lower than those in Comparative Example 3. Directly adding components A, B and C to wastewater will produce by-products, thereby reducing the flocculation effect. The method of first dissolving in a hydrogen peroxide solution and drying and then preparing the agent is better than directly adding components A, B and C to wastewater.

[0148] The above is based on the ideal embodiment of the present invention. Through the above description, relevant personnel can make various changes and modifications without departing from the technical concept of the present invention. The technical scope of the present invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. A method for preparing a pretreatment agent for wastewater before it enters an evaporator, characterized in that: The following steps are involved: S1: mixing potassium bicarbonate and sodium carbonate in a mass ratio of 1:2 to obtain a component A; S2: Mixing polyferric sulfate, polyaluminium chloride and a rare earth modifier in a ratio of 5:15:2-4, wherein the rare earth modifier is polyaluminium ferrosilicate, and the polyaluminium ferrosilicate is modified by lanthanum and cerium, wherein the lanthanum and the cerium account for 0.35%-0.45% and 0.05%-0.15% of the mass of the polyaluminium ferrosilicate, respectively, to obtain a component B material; S3: polyacrylamide, nano-alumina, nano-zirconia, chitosan and titanium dioxide are mixed together, wherein the particle sizes of the nano-alumina and nano-zirconia are both less than 50 nm, the mass ratio of the nano-alumina and nano-zirconia is 3:1, the total mass of the nano-alumina and nano-zirconia accounts for 20-30% of the mass of the polyacrylamide, the mass ratio of the titanium dioxide to the polyacrylamide is 1:10-20, and as a C component material, the mass of the chitosan accounts for 10-15% of the C component; S4: adding the component A substance, the component B substance and the component C substance to a 30% hydrogen peroxide solution at a mass ratio of 1:10-12:15-20, respectively, and the mass ratio of the total mass of the component A substance, the component B substance and the component C substance to the hydrogen peroxide solution is 1:5-10, to obtain a pretreatment solution; S5: drying the pretreatment solution at a temperature of 60-80° C. for 3-4 hours to obtain a pretreatment agent for wastewater before it enters an evaporator.

2. The method for preparing a pretreatment agent for wastewater before entering an evaporator according to claim 1, characterized in that: In the S4, the component A material, the component B material and the component C material are sequentially added into the hydrogen peroxide solution.

3. The method for preparing a pretreatment agent for wastewater before entering an evaporator according to claim 1, characterized in that: The hydrogen peroxide solution contains ozone, and the mass ratio of the hydrogen peroxide to the ozone is 1:1-2.

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