Biological nutritional agent and method for treating liquid crystal panel organic wastewater based on biological nutritional agent

Abstract

The invention discloses a biological nutritional agent which is prepared by the following steps: (1) dissolving an inorganic salt material in deionized water to obtain an inorganic salt solution; (2) adding a growth factor material and disodium ethylene diamine tetraacetate into the inorganic salt solution in the step (1), and uniformly mixing to obtain a basic solution A; (3) dispersing a high-molecular material in an organic solvent, after the high-molecular material is fully dispersed, adding the basic solution A in the step (2) into the high-molecular material, and fully stirring to obtain a uniform viscous pasty solution B; (4) preparing spherical particles from the viscous pasty solution B obtained in the step (3) through a plastic mold, and then carrying out high-temperature heat treatment on the spherical particles until the organic solvent is completely volatilized; and cooling to obtain the biological nutrient with the slow-release effect and the porous spherical structure. The invention also discloses a method for treating liquid crystal panel organic wastewater based on the biological nutrient.

Description

Technical Field

[0001] The invention relates to a biological nutrient and also to a method for treating liquid crystal panel organic wastewater based on the biological nutrient. Background Art

[0002] The production process of thin-film transistor liquid crystal displays (TFT-LCD) requires the use of a large amount of pure water and organic reagents, including tetramethylammonium hydroxide (TMAH), dimethyl sulfoxide (DMSO), chelating agents and other substances, which produces a large amount of difficult-to-treat organic wastewater. Studies have shown that the output of such organic wastewater is about 70,000 m 3 / d, and has the characteristics of high biological toxicity, complex types of pollutants, difficult biodegradation, low biodegradability, photoresist, and large emissions. At present, the methods for treating organic wastewater mainly include advanced oxidation methods (Fenton oxidation method, catalytic oxidation method, electrochemical oxidation method, etc.) and biological treatment methods. However, the advanced oxidation method has high treatment costs, large amounts of chemical agents, and high waste production. In the actual production and operation process, it is rarely used; biological treatment method has the advantages of high treatment efficiency, low operating costs, and low waste production. It is the most commonly used method for treating organic wastewater. However, when there are more organic and toxic substances in the wastewater, it will inhibit the activity of microorganisms, cause microecological imbalance, and reduce treatment efficiency.

[0003] At present, biological nutrients have been used in biochemical systems to enhance sludge activity, increase sludge acclimation rate, and improve system processing efficiency, but they generally have the characteristics of short effective time, fast expiration, single nutrient composition, and difficult preservation. For example, Chinese patent CN103224887B (application number 201310164864.2) discloses a wastewater biochemical treatment microbial nutrient, including fish meal, protease, alkaline lipase, alcohol lees and other substances, which has a high content of small molecule organic matter, but lacks trace elements required for microbial growth, and cannot quickly repair damaged sludge when the system is impacted by toxic substances such as heavy metals. Chinese patent CN115465958B (application number 202211171662.6) discloses a biological nutrient for sewage denitrification, which comprises solid raw materials composed of processed food raw materials or fruit and vegetable raw materials, water, amylase and other substances. Although expired and deteriorated substances can be converted into biological nutrient agents, their trace element content is low, and expired food is prone to breed a large number of useless bacteria, which consume the nutrients in the nutrient agent. Summary of the invention

[0004] Purpose of the invention: The purpose of the present invention is to provide a biological nutrient, which has high nutritional content, long action time, can resist the impact of water quality and quantity and toxic substances, and realize stable and efficient operation of the biochemical system; another purpose of the present invention is to provide a method for treating liquid crystal panel organic wastewater based on the above-mentioned biological nutrient, which adopts the biological nutrient of the present invention to coordinate the control of dissolved oxygen content, and can effectively improve the treatment efficiency of liquid crystal panel organic wastewater by biological treatment method.

[0005] Technical solution: The biological nutrient of the present invention is prepared by the following method, and the method steps are as follows:

[0006] (1) dissolving an inorganic salt material in deionized water to obtain an inorganic salt solution;

[0007] (2) adding growth factor material and disodium ethylenediaminetetraacetate (EDTA) to the inorganic salt solution of step (1), and mixing to obtain a basic solution A;

[0008] (3) dispersing the polymer material in an organic solvent. After the polymer material is fully dispersed, adding the base solution A of step (2) thereto, and stirring thoroughly to obtain a uniform viscous paste solution B;

[0009] (4) The viscous paste solution B of step (3) is formed into spherical particles by a plastic mold, and then the spherical particles are subjected to high-temperature heat treatment until the organic solvent is completely volatilized; after cooling, a porous spherical structured biological nutrient with a sustained-release effect is obtained.

[0010] Wherein, in step (1), the inorganic salt material is composed of the following components in parts by mass: 0.15-0.25 parts of potassium dihydrogen phosphate, 0.15-0.25 parts of dipotassium hydrogen phosphate, 0.1-0.15 parts of ferrous sulfate heptahydrate, 0.02-0.05 parts of zinc sulfate heptahydrate, 0.03-0.05 parts of magnesium sulfate heptahydrate, 0.02-0.05 parts of copper sulfate pentahydrate, 0.05-0.08 parts of manganese chloride tetrahydrate, 0.02-0.05 parts of cobalt chloride hexahydrate, 0.1-0.3 parts of ammonium molybdate, 0.02-0.05 parts of anhydrous calcium chloride and 0.01 parts of boric acid.

[0011] Wherein, in step (2), the growth factor material is composed of the following components in parts by weight: 2 to 2.3 parts of complex amino acid powder, 0.05 to 0.1 parts of L-cysteine, 0.25 to 0.3 parts of D-biotin, 0.05 to 0.1 parts of cytokinin and 0.5 to 0.7 parts of complex vitamins.

[0012] Wherein, in step (3), the polymer material is one of poly (3-hydroxybutyric acid-co-3-hydroxyvaleric acid), polylactic acid, polycaprolactone, poly β-hydroxybutyric acid or polylactic acid-polycaprolactone copolymer.

[0013] Wherein, in step (3), the organic solvent is one of chloroform, acetone or isopropanol.

[0014] Wherein, in step (3), the stirring rate is 70 to 120 rpm.

[0015] Among them, the biological nutrient uses a polymer skeleton material as a slow-release carrier, and encapsulates disodium ethylenediaminetetraacetic acid, a variety of inorganic salts and growth factors in it, forming a slow-release biological nutrient for liquid crystal panel organic wastewater with complex nutrients and long-term effect. The polymer dissolves in the organic solvent and the molecular chain opens; the nutrients are encapsulated and calcined, which not only volatilizes the organic solvent, but also forms a porous spherical structure.

[0016] The method for treating liquid crystal panel organic wastewater based on the above-mentioned biological nutrient agent specifically includes the following steps:

[0017] (1) Liquid crystal panel organic wastewater is passed into a biochemical pretreatment device filled with porous fillers; the concentration of activated sludge in the device is 1 to 2 g / L, and the pH of the wastewater in the device is adjusted to 7 to 8;

[0018] (2) Add 0.1-0.2 g / L of biological nutrient into the device, and control the DO in the device to maintain at 2-5 mg / L through the aeration device; the hydraulic retention time in the device is 24-48 h;

[0019] (3) After the reaction is completed, stop aeration, let it settle for 30 to 60 minutes, and then discharge the treated wastewater.

[0020] Wherein, in step (1), the filling amount of the porous filler in the device is 10% of the volume of the device (reactor). The porous filler is a polyurethane material with uniform pores, and the volume of a single filler is 5mm 3 , density is 18g / L, specific surface area is 1000m 2 / g. As the reaction proceeds, an aerobic environment can be constructed outside the filler due to aeration, while an anoxic / anaerobic microenvironment can be constructed inside the filler due to the presence of pores, thereby achieving nitrification and denitrification in one reactor. Refractory organic matter can first be biodegraded in the anoxic / anaerobic microenvironment, and the resulting degradation products can be further removed through aerobic reactions.

[0021] The porous filler has a density of 18g / L and is light in weight. When put into the device, the filler always floats above the wastewater within the initial 1 to 2 days and is difficult to show turbulence with the water flow, resulting in a long startup time, a low biofilm formation rate, and a poor removal efficiency. A fixed partition is set in the reactor. Within 1 to 2 days of reaction, the partition is set 1 / 3 to 1 / 2 below the water surface. The aperture of the partition is 1 to 2mm, which is smaller than the particle size of the filler (4 to 5mm). Therefore, the porous filler is controlled by the partition below the water surface, so that the filler is in contact with the wastewater and activated sludge at the beginning of the reaction, greatly shortening the biofilm formation period on the filler and allowing the device to start quickly. When the filler can show turbulence with the water flow, the partition is manually removed.

[0022] The biological nutrient of the present invention uses a polymer skeleton material as a sustained-release carrier to fully embed the nutrients therein, has good stability and long timeliness, can obtain a release period of more than 15 days after a one-time addition, and effectively avoids the problem of immediate release and insufficient long-term effect of liquid biological nutrient after addition; the selected polymer materials are all biodegradable polymers, which are green materials that are non-toxic and harmless to organisms on the one hand, and can also be used as an external carbon source for microbial growth on the other hand, which is beneficial to the removal of pollutants such as ammonia nitrogen and nitrate nitrogen in water bodies with a low carbon-nitrogen ratio, and reduces the addition of additional carbon sources; the biological nutrient of the present invention contains a variety of inorganic salts (including macro, medium and trace elements) and growth factors, which can promote the growth of microorganisms in water bodies with a large amount of The rapid growth and reproduction of refractory organic matter in the wastewater environment increases the diversity of microorganisms, thereby improving the degradation efficiency of organic matter by microorganisms and improving the system's resistance to shock loads. Among them, the functions of various growth factors are as follows: amino acids and vitamins are the basic nutrients required for microbial growth and can accelerate the reproduction of microorganisms; biotin is a coenzyme of various carboxylases, which can improve the removal capacity of activated sludge for BOD and COD and enhance the formation of flocculant micelles; cytokinin is an indispensable hormone for regulating cell division and can promote the division and reproduction of microorganisms; L-cysteine ​​is a sulfur-containing α-amino acid that can form insoluble thiolates with various toxic and harmful metal ions such as copper, silver, and mercury, playing a role in biological detoxification. Since the nitrification and denitrification activities of microorganisms are easily inhibited by heavy metals and organic matter, when the system is impacted by toxic substances such as heavy metals, it is difficult for the activated sludge to recover its activity in a short period of time. The EDTA in the biological nutrient of the present invention can combine with a variety of metal ions to form a stable complex, remove the inhibition of heavy metals on enzyme activity, play a role in rapid detoxification when the system is poisoned, help quickly repair the damaged activated sludge, quickly improve the sludge activity and concentration, and restore the treatment efficiency.

[0023] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: the biological nutrient of the present invention cooperates with the treatment method of the present invention to effectively enhance the activity of microorganisms in the biochemical system, improve the impact and damage resistance of sludge, establish the system's tolerance to toxic substances, and can also greatly shorten the biofilm formation period on the filler, so that the reactor can be started quickly; ultimately, the treatment efficiency of the biological treatment method for liquid crystal panel organic wastewater is improved, and the difficult-to-degrade organic matter in the wastewater, such as tetramethylammonium hydroxide (TMAH) and chelating agents, is completely degraded. DETAILED DESCRIPTION

[0024] Example 1

[0025] The preparation method of the biological nutrient of the present invention comprises the following steps:

[0026] (1) 0.15 g of potassium dihydrogen phosphate, 0.15 g of dipotassium hydrogen phosphate, 0.13 g of ferrous sulfate heptahydrate, 0.03 g of zinc sulfate heptahydrate, 0.05 g of magnesium sulfate heptahydrate, 0.02 g of copper sulfate pentahydrate, 0.06 g of manganese chloride tetrahydrate, 0.02 g of cobalt chloride hexahydrate, 0.1 g of ammonium molybdate, 0.02 g of anhydrous calcium chloride and 0.01 g of boric acid were respectively placed in a 100 mL volumetric flask, 50 mL of deionized water was added thereto, and the mixture was fully dissolved and mixed to obtain an inorganic salt solution;

[0027] (2) 2 g of composite amino acid powder, 0.07 g of L-cysteine, 0.25 g of D-biotin, 0.06 g of cytokinin and 0.5 g of composite vitamins are respectively dissolved in the inorganic salt solution of step (1) and fully dissolved and mixed;

[0028] (3) Take 2 g of EDTA and dissolve it in the mixed solution of step (2), mix thoroughly and dilute to 100 mL to obtain basic solution A;

[0029] (4) 50 g of polylactic acid was added to a 250 mL beaker, 20 mL of chloroform was added thereto, and the mixture was completely dispersed by ultrasonication for 5 min; then 50 mL of the basic solution A of step (3) was added thereto, and the mixture was stirred at room temperature for 2 h to obtain a uniform viscous paste solution B; wherein the stirring rate was 70 rpm;

[0030] (5) The viscous paste solution B of step (4) is formed into spherical particles with a particle size of 5 mm through a plastic mold, and dried at 60° C. for 12 h until the organic solvent is completely volatilized, and after cooling, a porous spherical structured biological nutrient with a particle size of 5 mm is obtained.

[0031] Example 2

[0032] The preparation method of the biological nutrient of the present invention comprises the following steps:

[0033] (1) 0.15 g of potassium dihydrogen phosphate, 0.15 g of dipotassium hydrogen phosphate, 0.13 g of ferrous sulfate heptahydrate, 0.03 g of zinc sulfate heptahydrate, 0.05 g of magnesium sulfate heptahydrate, 0.02 g of copper sulfate pentahydrate, 0.06 g of manganese chloride tetrahydrate, 0.02 g of cobalt chloride hexahydrate, 0.1 g of ammonium molybdate, 0.02 g of anhydrous calcium chloride and 0.01 g of boric acid were respectively placed in a 100 mL volumetric flask, 50 mL of deionized water was added thereto, and the mixture was fully dissolved and mixed to obtain an inorganic salt solution;

[0034] (2) 2 g of composite amino acid powder, 0.07 g of L-cysteine, 0.25 g of D-biotin, 0.06 g of cytokinin and 0.5 g of composite vitamins are respectively dissolved in the inorganic salt solution of step (1) and fully dissolved and mixed;

[0035] (3) Take 4 g of EDTA and dissolve it in the mixed solution of step (2), mix thoroughly and dilute to 100 mL to obtain basic solution A;

[0036] (4) 70 g of polylactic acid was added to a 250 mL beaker, 20 mL of chloroform was added thereto, and ultrasonication was performed for 10 min to completely disperse it; then 50 mL of the basic solution A of step (3) was added thereto, and stirred at room temperature for 4 h to obtain a uniform viscous paste solution B; wherein the stirring rate was 120 rpm;

[0037] (5) The viscous paste solution B of step (4) is formed into spherical particles with a particle size of 8 mm through a plastic mold, and dried at 60° C. for 24 h until the organic solvent is completely volatilized, and after cooling, a porous spherical structured biological nutrient with a particle size of 8 mm is obtained.

[0038] Example 3

[0039] Application of the biological nutrient prepared in Example 1 in treating organic wastewater from liquid crystal panels: Organic wastewater from a liquid crystal panel factory in Chengdu, the initial water quality indicators of the organic wastewater are: total nitrogen concentration of 40 mg / L, ammonia nitrogen concentration of 0.5 mg / L, TOC of 120 mg / L, COD of 350 mg / L, and pH of 4.5.

[0040] The method for treating liquid crystal panel organic wastewater of the present invention specifically comprises the following steps:

[0041] (1) The organic wastewater from the liquid crystal panel factory is introduced into a biochemical pretreatment device through a water inlet pipe, wherein the concentration of activated sludge in the device is 1.5 mg / L; the device is filled with porous fillers accounting for 10% of the volume of the device;

[0042] (2) adjusting the rotation speed of the stirring blade in the device to 100 rpm, making the water quality and quantity in the device uniform by the stirring blade, and then adjusting the pH of the wastewater in the device to 7.5 by the acid-base dosing device;

[0043] (3) adding 0.1 g / L of the biological nutrient of Example 1 into the device, starting the aeration device, and controlling the DO in the device to always be maintained at 2-5 mg / L; the hydraulic retention time in the device is set to 48 h;

[0044] (4) After the reaction is completed, the aeration device is turned off and allowed to settle for 30 to 60 minutes. Then, the outlet pipe switch of the device is turned on to measure the water quality of the effluent. In the effluent, the TN concentration is 7.6 mg / L, the NH3-N concentration is ND, the TOC concentration is 4.5 mg / L, and the COD concentration is 12.6 mg / L.

[0045] The present invention provides a dissolved oxygen meter capable of online monitoring of dissolved oxygen in a biochemical pretreatment device, the dissolved oxygen meter is connected to an external PLC control box, and the dissolved oxygen concentration in the device is controlled in real time (DO needs to be maintained between 2 and 5 mg / L); the PLC control box is connected to a power supply through a frequency converter, when the dissolved oxygen signal output by the dissolved oxygen meter is higher than 5 mg / L, the PLC control box controls the power supply to be disconnected through the frequency converter, causing the aeration device to stop aeration; when the dissolved oxygen signal output by the dissolved oxygen meter is lower than 2 mg / L, the PLC control box controls the power supply to be reconnected through the frequency converter, and the aeration device starts aeration, so that the dissolved oxygen in the device is always maintained between 2 and 5 mg / L.

[0046] Example 4

[0047] Application of the biological nutrient prepared in Example 2 in treating organic wastewater from liquid crystal panels: Organic wastewater from a liquid crystal panel factory in Chengdu, the initial water quality indicators of the organic wastewater are: total nitrogen concentration of 40 mg / L, ammonia nitrogen concentration of 0.5 mg / L, TOC of 120 mg / L, COD of 350 mg / L, and pH of 4.5.

[0048] The method for treating liquid crystal panel organic wastewater of the present invention specifically comprises the following steps:

[0049] (1) The organic wastewater from the liquid crystal panel factory is introduced into a biochemical pretreatment device through a water inlet pipe, wherein the concentration of activated sludge in the device is 1.5 mg / L; the device is filled with porous fillers accounting for 10% of the volume of the device;

[0050] (2) adjusting the rotation speed of the stirring blade in the device to 100 rpm, making the water quality and quantity in the device uniform by the stirring blade, and then adjusting the pH of the wastewater in the device to 7.5 by the acid-base dosing device;

[0051] (3) Add 0.1 g / L of the biological nutrient of Example 2 into the device, start the aeration device, and control the DO in the device to always maintain at 2-5 mg / L; the hydraulic retention time in the device is set to 48 h;

[0052] (4) After the reaction is completed, the aeration device is turned off and allowed to settle for 30 to 60 minutes. Then, the outlet pipe switch of the device is turned on to measure the water quality of the effluent. In the effluent, the TN concentration is 8.3 mg / L, the NH3-N concentration is ND, the TOC concentration is 5.2 mg / L, and the COD concentration is 13.8 mg / L.

[0053] Example 5

[0054] Example 1 Application of the biological nutrient prepared in treating organic wastewater from liquid crystal panels: Organic wastewater from a liquid crystal panel factory in Wuhan, the initial water quality indicators of the organic wastewater are: total nitrogen concentration of 35mg / L, ammonia nitrogen concentration of 1.5mg / L, TOC of 55mg / L, COD of 170mg / L, Cu 2+ The concentration is 9.4 mg / L and the pH is 4.5.

[0055] The method for treating liquid crystal panel organic wastewater of the present invention specifically comprises the following steps:

[0056] (1) The organic wastewater from the liquid crystal panel factory is introduced into a biochemical pretreatment device through a water inlet pipe, wherein the concentration of activated sludge in the device is 1.5 mg / L; the device is filled with porous fillers accounting for 10% of the volume of the device;

[0057] (2) adjusting the rotation speed of the stirring blade in the device to 100 rpm, making the water quality and quantity in the device uniform by the stirring blade, and then adjusting the pH of the wastewater in the device to 7.5 by the acid-base dosing device;

[0058] (3) adding 0.1 g / L of the biological nutrient of Example 1 into the device, starting the aeration device, and controlling the DO in the device to always be maintained at 2-5 mg / L; the hydraulic retention time in the device is set to 48 h;

[0059] (4) After the reaction was completed, the aeration device was turned off and allowed to settle for 30 to 60 minutes. Then, the outlet pipe switch of the device was turned on to measure the water quality of the effluent. In the effluent, the TN concentration was 9.5 mg / L, the NH3-N concentration was ND, the TOC concentration was 6.5 mg / L, the COD concentration was 18 mg / L, and the Cu 2+ Concentration: 0.29mg / L.

[0060] Comparative Example 1

[0061] A method for preparing a biological nutrient comprises the following steps:

[0062] (1) 0.15 g of potassium dihydrogen phosphate, 0.15 g of dipotassium hydrogen phosphate, 0.13 g of ferrous sulfate heptahydrate, 0.03 g of zinc sulfate heptahydrate, 0.05 g of magnesium sulfate heptahydrate, 0.02 g of copper sulfate pentahydrate, 0.06 g of manganese chloride tetrahydrate, 0.02 g of cobalt chloride hexahydrate, 0.1 g of ammonium molybdate, 0.02 g of anhydrous calcium chloride and 0.01 g of boric acid were respectively placed in a 100 mL volumetric flask, 50 mL of deionized water was added thereto, and the mixture was fully dissolved and mixed to obtain an inorganic salt solution;

[0063] (2) 2 g of complex amino acids, 0.07 g of L-cysteine, 0.25 g of D-biotin, 0.06 g of cytokinin and 0.5 g of complex vitamins are respectively dissolved in the inorganic salt solution of step (1), and the mixture is fully dissolved and mixed, and then the volume is fixed to 100 mL to obtain a mixed solution C;

[0064] (3) 50 g of polylactic acid was added to a 250 mL beaker, 20 mL of chloroform was added thereto, and ultrasonication was performed for 5 min to completely disperse it; then 50 mL of the mixed solution C of step (2) was added thereto, and stirred at room temperature for 2 h to obtain a uniform viscous paste solution; wherein the stirring rate was 70 rpm;

[0065] (4) The viscous paste solution of step (3) is formed into spherical particles with a particle size of 5 mm through a plastic mold, and dried at 60° C. for 12 h until the organic solvent is completely volatilized, and after cooling, a porous spherical structured biological nutrient with a particle size of 5 mm is obtained.

[0066] Comparative Example 2

[0067] The method for treating organic wastewater from a liquid crystal panel factory in Comparative Example 2 is basically the same as that in Example 3, with the only difference being that in step (3), the biological nutrient used in the method of Comparative Example 2 is the basic solution A prepared in step (3) of Example 1, and the dosage of the basic solution A is 0.1 mL / L.

[0068] In the effluent of Comparative Example 2, the TN concentration was 25.7 mg / L, the NH3-N concentration was 0.15 mg / L, the TOC concentration was 35.6 mg / L, and the COD concentration was 95 mg / L.

[0069] By comparing Comparative Example 2 with Example 3, it can be seen that when the nutrients are coated with biodegradable polymers, the treatment effect is better. Under the same dosage, the TN removal rate of Example 3 is increased by 45.25%, the NH3-N removal rate is increased by 30%, the TOC removal rate is increased by 25.92%, and the COD removal rate is increased by 32.96%.

[0070] Comparative Example 3

[0071] The method for treating organic wastewater from a liquid crystal panel factory in Comparative Example 3 is basically the same as that in Example 5, with the only difference being that in step (3), the biological nutrient used in the method of Comparative Example 3 is the biological nutrient prepared in Comparative Example 1 (the biological nutrient in Comparative Example 1 does not contain EDTA), and the dosage of the biological nutrient is 0.1 g / L.

[0072] In the effluent of comparative example 3, the concentration of TN was 28 mg / L, the concentration of NH3-N was 0.76 mg / L, the concentration of TOC was 32.5 mg / L, the concentration of COD was 89.6 mg / L, and the concentration of Cu 2+ The concentration is 9.28mg / L.

[0073] By comparing Example 3 with Example 5, it can be seen that when the influent is impacted by heavy metal copper ions, the EDTA contained in the biological nutrient can effectively improve the impact resistance of the activated sludge and achieve better treatment effect. Under the same dosage, the TN removal rate of Example 5 is increased by 52.86%, the NH3-N removal rate is increased by 50.67%, the TOC removal rate is increased by 47.27%, and the COD removal rate is increased by 42.12%.

[0074] Comparative Example 4

[0075] The method for treating organic wastewater from a liquid crystal panel factory in Comparative Example 4 is basically the same as that in Example 3, with the only difference being that in step (3), the DO in the control device is not always maintained at 2-5 mg / L, but the aeration device is always in an aeration state.

[0076] In the effluent of Comparative Example 4, the TN concentration was 28.5 mg / L, the NH3-N concentration was ND, the TOC concentration was 41.5 mg / L, and the COD concentration was 127 mg / L.

[0077] By comparing Comparative Example 4 with Example 3, it can be seen that when in a continuous aeration state, the dissolved oxygen in the reactor will continue to increase until it is saturated, and the anoxic / anaerobic microenvironment inside the filler is difficult to form, and the treatment effect of difficult-to-degrade organic matter becomes poor. Under the same dosage, the TN removal rate in Example 3 is increased by 52.25%, the TOC removal rate is increased by 30.83%, and the COD removal rate is increased by 32.69%.

[0078] Since the liquid crystal panel organic wastewater contains a large amount of difficult-to-degrade organic matter, such as tetramethylammonium hydroxide (TMAH), chelating agents and other substances, when the concentration is high, such substances are likely to cause the collapse of the aerobic biological system, and the metabolites they produce (such as formaldehyde, hydrogen peroxide, etc.) are biologically toxic and easily cause the death or inactivation of microorganisms, so it is difficult to remove them through a simple aerobic biological treatment method; the present invention can fill the biochemical pretreatment device with porous fillers, and as the reaction proceeds, an aerobic environment is formed in the reactor, and an anoxic / anaerobic microenvironment with attached biofilms is formed inside the porous fillers, and the difficult-to-degrade organic matter can be biodegraded through the anoxic / anaerobic microenvironment, and the generated degradation products can be further removed through aerobic reactions (such as TMAH can gradually release ammonium ions through the anaerobic environment, and the formed ammonia nitrogen can be further removed by aeration through the aerobic environment in the reactor). When the DO concentration in the reactor is too high, the activated sludge is easy to break and digest, and the anoxic / anaerobic microenvironment in the pores of the filler is easy to be destroyed, and the difficult-to-degrade organic matter is difficult to be biodegraded through anoxic / anaerobic reactions. At the same time, when the DO concentration in the reactor is too low, an overall anaerobic environment is easily formed, and substances such as ammonia nitrogen are difficult to remove. Therefore, the DO of the reactor in the present invention needs to be maintained at 2-5 mg / L.

Claims

1. A biological nutrient, characterized in that: The method is as follows: (1) dissolving an inorganic salt material in deionized water to obtain an inorganic salt solution; (2) adding growth factor material and disodium ethylenediaminetetraacetate to the inorganic salt solution of step (1), and mixing to obtain a basic solution A; (3) dispersing the polymer material in an organic solvent, and after the polymer material is fully dispersed, adding the base solution A of step (2) thereto, and stirring thoroughly to obtain a viscous paste solution B; (4) The viscous paste solution B of step (3) is made into spherical particles by a plastic mold, and then the spherical particles are subjected to high-temperature heat treatment until the organic solvent is completely volatilized; after cooling, a biological nutrient with a porous spherical structure is obtained.

2. The biological nutrient according to claim 1, characterized in that: In step (1), the inorganic salt material is composed of the following components in parts by weight: 0.15-0.25 parts of potassium dihydrogen phosphate, 0.15-0.25 parts of dipotassium hydrogen phosphate, 0.1-0.15 parts of ferrous sulfate heptahydrate, 0.02-0.05 parts of zinc sulfate heptahydrate, 0.03-0.05 parts of magnesium sulfate heptahydrate, 0.02-0.05 parts of copper sulfate pentahydrate, 0.05-0.08 parts of manganese chloride tetrahydrate, 0.02-0.05 parts of cobalt chloride hexahydrate, 0.1-0.3 parts of ammonium molybdate, 0.02-0.05 parts of anhydrous calcium chloride and 0.01 parts of boric acid.

3. The biological nutrient according to claim 1, characterized in that: In step (2), the growth factor material is composed of the following components in parts by weight: 2 to 2.3 parts of complex amino acid powder, 0.05 to 0.1 parts of L-cysteine, 0.25 to 0.3 parts of D-biotin, 0.05 to 0.1 parts of cytokinin and 0.5 to 0.7 parts of complex vitamins.

4. The biological nutrient according to claim 1, characterized in that: In step (3), the polymer material is one of poly (3-hydroxybutyric acid-co-3-hydroxyvaleric acid), polylactic acid, polycaprolactone, poly β-hydroxybutyric acid or polylactic acid-polycaprolactone copolymer.

5. The biological nutrient according to claim 1, characterized in that: In step (3), the mass volume ratio of the polymer material to the basic solution A is 1-1.4 g:1 mL.

6. The biological nutrient according to claim 1, characterized in that: In step (3), the organic solvent is one of chloroform, acetone or isopropanol.

7. The biological nutrient according to claim 1, characterized in that: In step (3), the stirring rate is 70 to 120 rpm and the stirring time is 2 to 4 h.

8. The biological nutrient according to claim 1, characterized in that: In step (4), the heat treatment temperature is 60° C. and the treatment time is 12 to 24 hours.

9. The method for treating liquid crystal panel organic wastewater using the biological nutrient according to claim 1, characterized in that: The steps include: (1) Liquid crystal panel organic wastewater is passed into a biochemical pretreatment device filled with porous fillers; the concentration of activated sludge in the device is 1 to 2 g / L, and the pH of the wastewater in the device is adjusted to 7 to 8; (2) Add 0.1-0.2 g / L of biological nutrient into the device, and control the DO in the device to maintain at 2-5 mg / L through the aeration device; the hydraulic retention time in the device is 24-48 h; (3) After the reaction is completed, stop aeration, let it settle for 30 to 60 minutes, and then discharge the treated wastewater.

10. The method according to claim 9, characterized in that: In step (1), the filling amount of the porous filler in the device is 10-15% of the volume of the device.