A high-efficiency composite carbon source sewage treatment agent and preparation method thereof

Abstract

The invention discloses a high-efficiency composite carbon source sewage treatment agent and a preparation method thereof, belonging to the technical field of sewage treatment, comprising the following components in percentage by mass: 1-3% polyvinyl alcohol, 1-4% sodium formate, 2-5% humic acid, 2-14% modified loofah, 4-16% modified chitosan, 5-20% glucose, 5-20% sodium propionate and 48-51% water; the high-efficiency composite carbon source sewage treatment agent can effectively reduce COD and total nitrogen.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a high-efficiency composite carbon source sewage treatment agent and a preparation method thereof. Background Art

[0002] In the sewage treatment process, carbon source is a key nutrient for microbial metabolism, especially in the denitrification process. Adequate carbon source can effectively increase the activity of denitrifying bacteria, thereby promoting the reduction of nitrate and nitrite.

[0003] According to the form of carbon sources, they can be divided into liquid carbon sources and solid carbon sources. However, the dosage of liquid carbon sources is difficult to control, and there is a risk of excessive organic matter in the effluent. Solid carbon sources can be divided into synthetic carbon sources, natural carbon sources and blended carbon sources according to their component characteristics. However, traditional liquid carbon sources (such as methanol, acetic acid, etc.) are limited in their application in large-scale sewage treatment due to their large dosage and certain safety risks.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a high-efficiency composite carbon source sewage treatment agent and a preparation method thereof, which has excellent sewage treatment effect and can effectively reduce COD and total nitrogen.

[0006] To achieve the above object, the first aspect of the present invention provides a high-efficiency composite carbon source sewage treatment agent, comprising the following components in percentage by mass: 1-3% polyvinyl alcohol, 1-4% sodium formate, 2-5% humic acid, 2-14% modified loofah, 4-16% modified chitosan, 5-20% glucose, 5-20% sodium propionate, and 48-51% water;

[0007] The preparation method of the modified loofah comprises the following steps: adding 10 parts of loofah powder, 0.5-2 parts of ammonium bicarbonate, 0.5-1.5 parts of zinc chloride and 0.2-0.6 parts of citric acid to 20-50 parts of nitric acid solution, stirring evenly, heat treating, washing and drying to obtain pretreated loofah powder; adding 10 parts of pretreated loofah powder, 2-4 parts of manganese sulfate solution and 2-4 parts of ferric sulfate solution to 20-50 parts of water, stirring evenly, adding 0.5-2 parts of ferrous sulfate and 0.5-2 parts of sodium borohydride, stirring evenly, filtering, washing and drying to obtain the modified loofah.

[0008] As an embodiment of the present invention, the particle size of the loofah powder is 50-400 meshes.

[0009] As an embodiment of the present invention, the molar concentration of the nitric acid solution is 0.5~2 mol / L.

[0010] As an embodiment of the present invention, the molar concentration of the manganese sulfate solution is 0.5~2 mol / L.

[0011] As an embodiment of the present invention, the molar concentration of the ferric sulfate solution is 0.5~2 mol / L.

[0012] As an embodiment of the present invention, the temperature of the heat treatment is 160-200° C., and the time of the heat treatment is 60-180 min.

[0013] As an embodiment of the present invention, the preparation method of the modified chitosan is: chitosan is subjected to plasma treatment to obtain a precursor; 10 parts of the precursor, 0.5-1 parts of hexadecyltrimethylammonium bromide, 1-2 parts of sodium alginate, and 0.4-0.8 parts of calcium chloride are added to 20-50 parts of water, stirred evenly, and dried to obtain modified chitosan.

[0014] As an embodiment of the present invention, the power of the plasma treatment is 600-800 W, and the time is 4-12 min.

[0015] As an embodiment of the present invention, the molecular weight of the polyvinyl alcohol is 1000~4000.

[0016] As an embodiment of the present invention, the mass ratio of the modified loofah to the modified chitosan is 1:(1.25-2).

[0017] The second aspect of the present invention provides a method for preparing a high-efficiency composite carbon source sewage treatment agent, comprising the following steps:

[0018] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, stirred evenly, and then modified loofah and modified chitosan are added, stirred evenly, so as to obtain a high-efficiency composite carbon source sewage treatment agent.

[0019] The beneficial effects of the present invention are as follows: (1) the addition of sodium formate, polyvinyl alcohol, glucose and sodium propionate of the present invention can provide electrons required for the denitrification reaction, and quickly provide electron donors for heterotrophic bacteria and denitrifying bacteria in the sewage treatment process. In the denitrification process, nitrate and nitrite are reduced to nitrogen gas, which improves the growth and reproduction of microorganisms and promotes the degradation of organic matter. The addition of polyvinyl alcohol effectively improves the stability of the system, and preliminarily adsorbs and precipitates pollutants such as suspended matter and heavy metals in the sewage, thereby improving the stability and efficiency of the microorganisms.

[0020] (2) The present invention uses cheap loofah powder to prepare modified loofah, and mixes it with ammonium bicarbonate, zinc chloride, and citric acid in a nitric acid solution to effectively improve the activity of the loofah, improve the specific surface area and porosity of the loofah, and then reduce manganese and iron in an aqueous solution to load them on the loofah, thereby improving the surface activity, enhancing the electrostatic adsorption capacity of negatively charged organic matter, catalyzing the oxidative degradation of organic pollutants, and effectively improving the adsorption capacity of soluble organic matter and suspended particulate matter. At the same time, the modified loofah provides a carrier for the attachment and growth of microorganisms (such as denitrifying bacteria and nitrifying bacteria) in sewage treatment. At the same time, iron and manganese have a certain promoting effect on microbial metabolism, effectively improving the removal effect of COD and total nitrogen. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are 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.

[0022] In the present invention, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0023] In the present invention, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are deemed to be continuous and include the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0024] In the present invention, there is no particular limitation on the specific dispersion and stirring treatment methods.

[0025] The “parts” mentioned in the present invention are all parts by mass.

[0026] Unless otherwise specified, the components, raw materials or instruments used in the embodiments and comparative examples of the present invention are all commercially available raw materials or instruments, and the components and raw materials used in each parallel experiment are all of the same kind.

[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0028] The embodiment of the present invention provides a high-efficiency composite carbon source sewage treatment agent, comprising the following components in percentage by mass: 1-3% polyvinyl alcohol, 1-4% sodium formate, 2-5% humic acid, 2-14% modified loofah, 4-16% modified chitosan, 5-20% glucose, 5-20% sodium propionate, and 48-51% water;

[0029] The preparation method of the modified loofah comprises the following steps: adding 10 parts of loofah powder, 0.5-2 parts of ammonium bicarbonate, 0.5-1.5 parts of zinc chloride and 0.2-0.6 parts of citric acid to 20-50 parts of nitric acid solution, stirring evenly, heat treating, washing and drying to obtain pretreated loofah powder; adding 10 parts of pretreated loofah powder, 2-4 parts of manganese sulfate solution and 2-4 parts of ferric sulfate solution to 20-50 parts of water, stirring evenly, adding 0.5-2 parts of ferrous sulfate and 0.5-2 parts of sodium borohydride, stirring evenly, filtering, washing and drying to obtain the modified loofah.

[0030] The present invention creatively combines the above-mentioned organic carbon source and inorganic carbon source to obtain a high-efficiency composite carbon source sewage treatment agent with excellent sewage treatment effect, which can effectively reduce the COD and total nitrogen of sewage and has broad application prospects.

[0031] Among them, the addition of sodium formate, polyvinyl alcohol, glucose and sodium propionate can provide the electrons required for the denitrification reaction, and quickly provide electron donors for heterotrophic bacteria and denitrifying bacteria in the sewage treatment process. In the process of denitrification, nitrate and nitrite are reduced to nitrogen gas, which improves the growth and reproduction of microorganisms and promotes the degradation of organic matter. The addition of polyvinyl alcohol effectively improves the stability of the system, and preliminarily adsorbs and precipitates suspended matter and heavy metals and other pollutants in the sewage, thereby improving the stability and efficiency of microorganisms.

[0032] The invention uses cheap loofah powder to prepare modified loofah, and mixes the loofah powder with ammonium bicarbonate, zinc chloride and citric acid in a nitric acid solution to effectively improve the activity of the loofah, improve the specific surface area and porosity of the loofah, and then reduce manganese and iron in an aqueous solution to load them on the loofah, thereby improving the surface activity, enhancing the electrostatic adsorption capacity of negatively charged organic matter, catalyzing the oxidative degradation of organic pollutants, and effectively improving the adsorption capacity of soluble organic matter and suspended particulate matter. At the same time, the modified loofah provides a carrier for the attachment and growth of microorganisms (such as denitrifying bacteria and nitrifying bacteria) in sewage treatment, and at the same time, iron and manganese have a certain promoting effect on microbial metabolism, effectively improving the removal effect of COD and total nitrogen.

[0033] In one embodiment, the particle size of the loofah powder is 50-400 mesh.

[0034] The loofah powder can be purchased commercially or obtained by crushing the loofah.

[0035] In one embodiment, the molar concentration of the nitric acid solution is 0.5-2 mol / L.

[0036] In one embodiment, the molar concentration of the manganese sulfate solution is 0.5-2 mol / L.

[0037] In one embodiment, the molar concentration of the ferric sulfate solution is 0.5-2 mol / L.

[0038] In one embodiment, the heat treatment temperature is 160-200° C., and the heat treatment time is 60-180 min.

[0039] In one embodiment, the preparation method of the modified chitosan is: subjecting chitosan to plasma treatment to obtain a precursor; adding 10 parts of the precursor, 0.5-1 parts of hexadecyltrimethylammonium bromide, 1-2 parts of sodium alginate, and 0.4-0.8 parts of calcium chloride to 20-50 parts of water, stirring evenly, and drying to obtain the modified chitosan.

[0040] Chitosan contains abundant amino and hydroxyl groups, and its molecular structure has positive charge and polymer bridging effect. It has good flocculation effect, fast clarification speed, and more effective ingredients. It is also natural and safe. After plasma treatment, the number of these groups increases, and more reactive sites are formed, which increases the surface roughness of chitosan, forms more micropores and active sites, and enhances the specific surface area and adsorption capacity. Hexadecyltrimethylammonium bromide (CTAB) is a cationic surfactant. After combining with chitosan, it makes the surface of chitosan positively charged and can efficiently adsorb negatively charged organic pollutants. The calcium ion cross-linked network formed by sodium alginate and calcium chloride enhances the mechanical strength and stability of the material, and provides additional adsorption sites for capturing macromolecular organic matter. After modification, it has better adsorption capacity, larger specific surface area and significantly enhanced catalytic performance. It effectively improves the removal effect of COD and total nitrogen.

[0041] In one embodiment, the plasma treatment is performed at a power of 600-800 W and for a time of 4-12 min.

[0042] In one embodiment, the molecular weight of the polyvinyl alcohol is 1000-4000.

[0043] In one embodiment, the mass ratio of the modified loofah to the modified chitosan is 1:(1.25-2).

[0044] An embodiment of the present invention provides a method for preparing a high-efficiency composite carbon source sewage treatment agent, comprising the following steps:

[0045] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, stirred evenly, and then modified loofah and modified chitosan are added, stirred evenly, so as to obtain a high-efficiency composite carbon source sewage treatment agent.

[0046] The following examples are provided to facilitate understanding of the present invention. These examples are not provided to limit the scope of the claims. Example 1

[0047] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand name CP1000), 3% sodium formate, 4% humic acid, 6% modified loofah, 12% modified chitosan, 12% glucose, 10% sodium propionate and 51% water.

[0048] The mass ratio of the modified loofah to the modified chitosan is 1:2.

[0049] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 1.5 parts of ammonium bicarbonate, 1 part of zinc chloride, and 0.5 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0050] (2) Add 10 parts of pretreated loofah powder, 3 parts of 1 mol / L manganese sulfate solution, and 3 parts of 1 mol / L ferric sulfate solution into 40 parts of water, stir at 200 rpm, add 1.5 parts of ferrous sulfate and 1.5 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah.

[0051] The preparation method of the modified chitosan is as follows: (1) placing chitosan in a plasma reaction container, treating it at a voltage of 220V, normal temperature and pressure (one atmosphere) and a power of 600W for 10 minutes, taking out the precursor;

[0052] (2) Add 10 parts of the precursor, 0.8 parts of hexadecyltrimethylammonium bromide, 1.5 parts of sodium alginate, and 0.5 parts of calcium chloride to 40 parts of water, stir evenly at 200 rpm, and dry to obtain modified chitosan.

[0053] Among them, chitosan comes from Yangzhou Hongxin Biology, industrial grade chitosan (specially used for flocculation and clarification).

[0054] The method for preparing the high-efficiency composite carbon source sewage treatment agent comprises the following steps:

[0055] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, and stirred evenly at a speed of 200 rpm. Modified loofah and modified chitosan are then added, and stirred evenly at a speed of 200 rpm to obtain a high-efficiency composite carbon source sewage treatment agent. Example 2

[0056] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 1% polyvinyl alcohol (brand name CP1000), 4% sodium formate, 2% humic acid, 2% modified loofah, 16% modified chitosan, 5% glucose, 20% sodium propionate and 50% water.

[0057] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 1.5 parts of ammonium bicarbonate, 1 part of zinc chloride, and 0.5 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0058] (2) Add 10 parts of pretreated loofah powder, 3 parts of 1 mol / L manganese sulfate solution, and 3 parts of 1 mol / L ferric sulfate solution into 40 parts of water, stir at 200 rpm, add 1.5 parts of ferrous sulfate and 1.5 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah.

[0059] The preparation method of the modified chitosan is as follows: (1) placing chitosan in a plasma reaction container, treating it at a voltage of 220V, normal temperature and pressure (one atmosphere) and a power of 600W for 10 minutes, taking out the precursor;

[0060] (2) Add 10 parts of the precursor, 0.8 parts of hexadecyltrimethylammonium bromide, 1.5 parts of sodium alginate, and 0.5 parts of calcium chloride to 40 parts of water, stir evenly at 200 rpm, and dry to obtain modified chitosan.

[0061] The method for preparing the high-efficiency composite carbon source sewage treatment agent comprises the following steps:

[0062] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, and stirred evenly at a speed of 200 rpm. Modified loofah and modified chitosan are then added, and stirred evenly at a speed of 200 rpm to obtain a high-efficiency composite carbon source sewage treatment agent. Example 3

[0063] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 3% polyvinyl alcohol (brand number CP1000), 1% sodium formate, 5% humic acid, 14% modified loofah, 4% modified chitosan, 20% glucose, 5% sodium propionate and 48% water.

[0064] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 1.5 parts of ammonium bicarbonate, 1 part of zinc chloride, and 0.5 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0065] (2) Add 10 parts of pretreated loofah powder, 3 parts of 1 mol / L manganese sulfate solution, and 3 parts of 1 mol / L ferric sulfate solution into 40 parts of water, stir at 200 rpm, add 1.5 parts of ferrous sulfate and 1.5 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah.

[0066] The preparation method of the modified chitosan is as follows: (1) placing chitosan in a plasma reaction container, treating it at a voltage of 220V, normal temperature and pressure (one atmosphere) and a power of 600W for 10 minutes, taking out the precursor;

[0067] (2) Add 10 parts of the precursor, 0.8 parts of hexadecyltrimethylammonium bromide, 1.5 parts of sodium alginate, and 0.5 parts of calcium chloride to 40 parts of water, stir evenly at 200 rpm, and dry to obtain modified chitosan.

[0068] The method for preparing the high-efficiency composite carbon source sewage treatment agent comprises the following steps:

[0069] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, and stirred evenly at a speed of 200 rpm. Modified loofah and modified chitosan are then added, and stirred evenly at a speed of 200 rpm to obtain a high-efficiency composite carbon source sewage treatment agent. Example 4

[0070] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand name CP1000), 3% sodium formate, 4% humic acid, 8% modified loofah, 10% modified chitosan, 12% glucose, 10% sodium propionate and 51% water.

[0071] The mass ratio of the modified loofah to the modified chitosan is 1:1.25.

[0072] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 1.5 parts of ammonium bicarbonate, 1 part of zinc chloride, and 0.5 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0073] (2) Add 10 parts of pretreated loofah powder, 3 parts of 1 mol / L manganese sulfate solution, and 3 parts of 1 mol / L ferric sulfate solution into 40 parts of water, stir at 200 rpm, add 1.5 parts of ferrous sulfate and 1.5 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah.

[0074] The preparation method of the modified chitosan is as follows: (1) placing chitosan in a plasma reaction container, treating it at a voltage of 220V, normal temperature and pressure (one atmosphere) and a power of 600W for 10 minutes, taking out the precursor;

[0075] (2) Add 10 parts of the precursor, 0.8 parts of hexadecyltrimethylammonium bromide, 1.5 parts of sodium alginate, and 0.5 parts of calcium chloride to 40 parts of water, stir evenly at 200 rpm, and dry to obtain modified chitosan.

[0076] The method for preparing the high-efficiency composite carbon source sewage treatment agent comprises the following steps:

[0077] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, and stirred evenly at a speed of 200 rpm. Modified loofah and modified chitosan are then added, and stirred evenly at a speed of 200 rpm to obtain a high-efficiency composite carbon source sewage treatment agent. Example 5

[0078] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand name CP1000), 3% sodium formate, 4% humic acid, 3% modified loofah, 15% modified chitosan, 12% glucose, 10% sodium propionate and 51% water.

[0079] The mass ratio of the modified loofah to the modified chitosan is 1:5.

[0080] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 1.5 parts of ammonium bicarbonate, 1 part of zinc chloride, and 0.5 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0081] (2) Add 10 parts of pretreated loofah powder, 3 parts of 1 mol / L manganese sulfate solution, and 3 parts of 1 mol / L ferric sulfate solution into 40 parts of water, stir at 200 rpm, add 1.5 parts of ferrous sulfate and 1.5 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah.

[0082] The preparation method of the modified chitosan is as follows: (1) placing chitosan in a plasma reaction container, treating it at a voltage of 220V, normal temperature and pressure (one atmosphere) and a power of 600W for 10 minutes, taking out the precursor;

[0083] (2) Add 10 parts of the precursor, 0.8 parts of hexadecyltrimethylammonium bromide, 1.5 parts of sodium alginate, and 0.5 parts of calcium chloride to 40 parts of water, stir evenly at 200 rpm, and dry to obtain modified chitosan.

[0084] The method for preparing the high-efficiency composite carbon source sewage treatment agent comprises the following steps:

[0085] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, and stirred evenly at a speed of 200 rpm. Modified loofah and modified chitosan are then added, and stirred evenly at a speed of 200 rpm to obtain a high-efficiency composite carbon source sewage treatment agent. Example 6

[0086] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand number CP1000), 3% sodium formate, 4% humic acid, 12% modified loofah, 6% modified chitosan, 12% glucose, 10% sodium propionate and 51% water.

[0087] The mass ratio of the modified loofah sponge to the modified chitosan is 1:0.5.

[0088] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 1.5 parts of ammonium bicarbonate, 1 part of zinc chloride, and 0.5 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0089] (2) Add 10 parts of pretreated loofah powder, 3 parts of 1 mol / L manganese sulfate solution, and 3 parts of 1 mol / L ferric sulfate solution into 40 parts of water, stir at 200 rpm, add 1.5 parts of ferrous sulfate and 1.5 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah.

[0090] The preparation method of the modified chitosan is as follows: (1) placing chitosan in a plasma reaction container, treating it at a voltage of 220V, normal temperature and pressure (one atmosphere) and a power of 600W for 10 minutes, taking out the precursor;

[0091] (2) Add 10 parts of the precursor, 0.8 parts of hexadecyltrimethylammonium bromide, 1.5 parts of sodium alginate, and 0.5 parts of calcium chloride to 40 parts of water, stir evenly at 200 rpm, and dry to obtain modified chitosan.

[0092] The method for preparing the high-efficiency composite carbon source sewage treatment agent comprises the following steps:

[0093] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, and stirred evenly at a speed of 200 rpm. Modified loofah and modified chitosan are then added, and stirred evenly at a speed of 200 rpm to obtain a high-efficiency composite carbon source sewage treatment agent. Example 7

[0094] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand name CP1000), 3% sodium formate, 4% humic acid, 6% modified loofah, 12% modified chitosan, 12% glucose, 10% sodium propionate and 51% water.

[0095] The mass ratio of the modified loofah to the modified chitosan is 1:2.

[0096] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 0.5 parts of ammonium bicarbonate, 1.5 parts of zinc chloride, and 0.2 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0097] (2) Add 10 parts of pretreated loofah powder, 2 parts of 1 mol / L manganese sulfate solution, and 4 parts of 1 mol / L ferric sulfate solution into 40 parts of water, stir at 200 rpm, add 0.5 parts of ferrous sulfate and 2 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah.

[0098] The preparation method of the modified chitosan is as follows: (1) placing chitosan in a plasma reaction container, treating it at a voltage of 220V, normal temperature and pressure (one atmosphere) and a power of 600W for 10 minutes, taking out the precursor;

[0099] (2) Add 10 parts of the precursor, 0.5 parts of hexadecyltrimethylammonium bromide, 2 parts of sodium alginate, and 0.4 parts of calcium chloride to 40 parts of water, stir evenly at 200 rpm, and dry to obtain modified chitosan.

[0100] The method for preparing the high-efficiency composite carbon source sewage treatment agent comprises the following steps:

[0101] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, and stirred evenly at a speed of 200 rpm. Modified loofah and modified chitosan are then added, and stirred evenly at a speed of 200 rpm to obtain a high-efficiency composite carbon source sewage treatment agent. Example 8

[0102] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand name CP1000), 3% sodium formate, 4% humic acid, 6% modified loofah, 12% modified chitosan, 12% glucose, 10% sodium propionate and 51% water.

[0103] The mass ratio of the modified loofah to the modified chitosan is 1:2.

[0104] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 2 parts of ammonium bicarbonate, 0.5 parts of zinc chloride, and 0.6 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0105] (2) Add 10 parts of pretreated loofah powder, 4 parts of 1 mol / L manganese sulfate solution, and 2 parts of 1 mol / L ferric sulfate solution into 40 parts of water, stir at 200 rpm, add 2 parts of ferrous sulfate and 0.5 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah.

[0106] The preparation method of the modified chitosan is as follows: (1) placing chitosan in a plasma reaction container, treating it at a voltage of 220V, normal temperature and pressure (one atmosphere) and a power of 600W for 10 minutes, taking out the precursor;

[0107] (2) Add 10 parts of the precursor, 1 part of hexadecyltrimethylammonium bromide, 1 part of sodium alginate, and 0.8 parts of calcium chloride to 40 parts of water, stir evenly at 200 rpm, and dry to obtain modified chitosan.

[0108] The method for preparing the high-efficiency composite carbon source sewage treatment agent comprises the following steps:

[0109] Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, and stirred evenly at a speed of 200 rpm. Modified loofah and modified chitosan are then added, and stirred evenly at a speed of 200 rpm to obtain a high-efficiency composite carbon source sewage treatment agent. Comparative Example 1

[0110] The difference between Comparative Example 1 and Example 1 is that Comparative Example 1 does not contain modified loofah, and the other aspects are the same.

[0111] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand number CP1000), 3% sodium formate, 4% humic acid, 12% modified chitosan, 12% glucose, 10% sodium propionate, and 57% water. Comparative Example 2

[0112] The difference between Comparative Example 2 and Example 1 is that Comparative Example 2 does not contain modified chitosan, and the other aspects are the same.

[0113] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand number CP1000), 3% sodium formate, 4% humic acid, 6% modified loofah, 12% glucose, 10% sodium propionate and 63% water. Comparative Example 3

[0114] The difference between Comparative Example 3 and Example 1 is that Comparative Example 3 does not contain modified loofah (replaced by an equal amount of modified chitosan), and the rest are the same.

[0115] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand number CP1000), 3% sodium formate, 4% humic acid, 18% modified chitosan, 12% glucose, 10% sodium propionate, and 51% water. Comparative Example 4

[0116] The difference between Comparative Example 4 and Example 1 is that Comparative Example 4 does not contain modified chitosan (replaced by an equal amount of modified loofah), and the rest are the same.

[0117] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand number CP1000), 3% sodium formate, 4% humic acid, 18% modified loofah, 12% glucose, 10% sodium propionate, and 51% water. Comparative Example 5

[0118] The difference between Comparative Example 5 and Example 1 is that an equal amount of sodium acetate is used to replace the modified loofah, and the other contents are the same.

[0119] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand name CP1000), 3% sodium formate, 4% humic acid, 6% sodium acetate, 12% modified chitosan, 12% glucose, 10% sodium propionate and 51% water. Comparative Example 6

[0120] The difference between Comparative Example 6 and Example 1 is that an equal amount of sodium acetate is used to replace the modified chitosan, and the other contents are the same.

[0121] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand number CP1000), 3% sodium formate, 4% humic acid, 6% modified loofah, 12% sodium acetate, 12% glucose, 10% sodium propionate and 51% water. Comparative Example 7

[0122] The difference between Comparative Example 7 and Example 1 is that the preparation method of the modified loofah is different, and the other aspects are the same.

[0123] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 3 parts of 1 mol / L manganese sulfate solution, and 3 parts of 1 mol / L ferric sulfate solution to 40 parts of water, stirring evenly at a speed of 200 rpm, adding 1.5 parts of ferrous sulfate and 1.5 parts of sodium borohydride, stirring evenly at a speed of 200 rpm, filtering, washing with water (the mass of water used is twice that of the product), and drying at 80° C. for 2 hours to obtain the modified loofah. Comparative Example 8

[0124] The difference between Comparative Example 8 and Example 1 is that the preparation method of the modified loofah is different, and the other aspects are the same.

[0125] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 1.5 parts of ammonium bicarbonate, 1 part of zinc chloride, and 0.5 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0126] (2) Add 10 parts of pretreated loofah powder and 3 parts of 1 mol / L ferric sulfate solution to 40 parts of water, stir at 200 rpm, add 1.5 parts of ferrous sulfate and 1.5 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah. Comparative Example 9

[0127] The difference between Comparative Example 9 and Example 1 is that the preparation method of the modified loofah is different, and the other aspects are the same.

[0128] The preparation method of the modified loofah is as follows: (1) adding 10 parts of 200-mesh loofah powder, 1.5 parts of ammonium bicarbonate, 1 part of zinc chloride, and 0.5 parts of citric acid to 40 parts of 1 mol / L nitric acid solution, stirring evenly at a speed of 200 rpm, heat-treating at 180° C. for 120 min to obtain a heat-treated product, washing with water (the amount of water used is twice that of the heat-treated product), and drying at 80° C. for 2 h to obtain a pretreated loofah powder;

[0129] (2) Add 10 parts of pretreated loofah powder and 3 parts of 1 mol / L manganese sulfate solution to 40 parts of water, stir at 200 rpm, add 1.5 parts of ferrous sulfate and 1.5 parts of sodium borohydride, stir at 200 rpm, filter, wash with water (the amount of water is twice that of the product), and dry at 80°C for 2 h to obtain modified loofah. Comparative Example 10

[0130] The difference between Comparative Example 10 and Example 1 is that loofah powder is used to replace the modified loofah, and the other aspects are the same.

[0131] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand name CP1000), 3% sodium formate, 4% humic acid, 6% 200-mesh loofah powder, 12% modified chitosan, 12% glucose, 10% sodium propionate, and 51% water. Comparative Example 11

[0132] The difference between Comparative Example 11 and Example 1 is that chitosan is used to replace modified chitosan, and the other contents are the same.

[0133] A high-efficiency composite carbon source sewage treatment agent comprises the following components in percentage by mass: 2% polyvinyl alcohol (brand number CP1000), 3% sodium formate, 4% humic acid, 6% modified loofah, 12% chitosan, 12% glucose, 10% sodium propionate and 51% water.

[0134] Test Case

[0135] Wastewater with a COD of 640 mg / L and a total nitrogen content of 1580 mg / L was treated with the composite carbon source wastewater treatment agent of the embodiment and the comparative example (with an addition amount of 1 wt %) for 24 hours, and the COD and total nitrogen removal rates were calculated.

[0136] Table 1

[0137] COD removal rate% Total nitrogen removal rate% Example 1 96.09 96.71 Example 2 87.81 89.62 Example 3 87.34 89.37 Example 4 95.94 96.58 Example 5 90.31 91.27 Example 6 90.16 91.20 Example 7 95.63 96.58 Example 8 95.31 96.20 Comparative Example 1 59.38 61.27 Comparative Example 2 58.59 60.25 Comparative Example 3 76.25 77.91 Comparative Example 4 76.56 78.48 Comparative Example 5 67.97 69.62 Comparative Example 6 67.81 69.05 Comparative Example 7 79.69 79.11 Comparative Example 8 82.03 80.89 Comparative Example 9 82.50 81.01 Comparative Example 10 70.47 71.52 Comparative Example 11 71.09 71.65

[0138] It can be seen from Table 1 that the composite carbon source sewage treatment agent of the present invention has an excellent sewage treatment effect and can effectively reduce COD and total nitrogen.

[0139] By comparing Examples 1 and 4 to 6, it can be seen that by controlling the mass ratio of the modified loofah to the modified chitosan to be 1:(1.25-2), the removal effect of COD and total nitrogen is further improved.

[0140] By comparing Example 1 with Comparative Examples 1 to 6, it can be seen that the modified loofah sponge and modified chitosan described in the present invention have a significant synergistic effect in removing COD and total nitrogen. Under the action of the two, the removal effect of COD and total nitrogen is significantly improved.

[0141] By comparing Example 1 with Comparative Examples 7 to 10, it can be seen that the modified loofah prepared by the method described in the present invention can significantly improve the removal effect of COD and total nitrogen, and the modified loofah prepared by different methods has different removal effects on COD and total nitrogen. The modified loofah prepared by the method of the present invention can more significantly improve the removal effect of COD and total nitrogen than the modified loofah prepared by other methods.

[0142] It can be seen from Example 1 and Comparative Example 11 that the modified chitosan of the present invention can significantly improve the removal effect of COD and total nitrogen.

[0143] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A high-efficiency composite carbon source sewage treatment agent, characterized in that: The invention is composed of the following components in percentage by mass: 1-3% polyvinyl alcohol, 1-4% sodium formate, 2-5% humic acid, 2-14% modified loofah, 4-16% modified chitosan, 5-20% glucose, 5-20% sodium propionate, and 48-51% water; The preparation method of the modified loofah is as follows: 10 parts of loofah powder, 0.5-2 parts of ammonium bicarbonate, 0.5-1.5 parts of zinc chloride, and 0.2-0.6 parts of citric acid are added to 20-50 parts of nitric acid solution, stirred evenly, heat-treated, washed, and dried to obtain pretreated loofah powder; 10 parts of pretreated loofah powder, 2-4 parts of manganese sulfate solution, and 2-4 parts of ferric sulfate solution are added to 20-50 parts of water, stirred evenly, 0.5-2 parts of ferrous sulfate and 0.5-2 parts of sodium borohydride are added, stirred evenly, filtered, washed, and dried to obtain the modified loofah; The heat treatment temperature is 160-200°C and the heat treatment time is 60-180min; The preparation method of the modified chitosan is as follows: chitosan is subjected to plasma treatment to obtain a precursor; 10 parts of the precursor, 0.5-1 parts of hexadecyltrimethylammonium bromide, 1-2 parts of sodium alginate, and 0.4-0.8 parts of calcium chloride are added to 20-50 parts of water, stirred evenly, and dried to obtain the modified chitosan; The mass ratio of the modified loofah sponge to the modified chitosan is 1:(1.25-2).

2. The high-efficiency composite carbon source sewage treatment agent according to claim 1, characterized in that: The particle size of the loofah powder is 50-400 meshes.

3. The high-efficiency composite carbon source sewage treatment agent according to claim 1, characterized in that: The molar concentration of the nitric acid solution is 0.5-2 mol / L.

4. The high-efficiency composite carbon source sewage treatment agent according to claim 1, characterized in that: The molar concentration of the manganese sulfate solution is 0.5-2 mol / L; The molar concentration of the ferric sulfate solution is 0.5-2 mol / L.

5. The high-efficiency composite carbon source sewage treatment agent according to claim 1, characterized in that: The power of the plasma treatment is 600-800 W, and the time is 4-12 min.

6. The high-efficiency composite carbon source sewage treatment agent according to claim 1, characterized in that: The molecular weight of the polyvinyl alcohol is 1000-4000.

7. The method for preparing a high-efficiency composite carbon source sewage treatment agent according to any one of claims 1 to 6, characterized in that: The following steps are involved: Polyvinyl alcohol, sodium formate, humic acid, glucose and sodium propionate are added into water, stirred evenly, and then modified loofah and modified chitosan are added, stirred evenly, so as to obtain a high-efficiency composite carbon source sewage treatment agent.