Method for treating slaughterhouse wastewater and water treatment agent

Abstract

The present application relates to sewage treatment technical field, propose a kind of slaughterhouse sewage treatment method and water treatment agent, water treatment agent, raw material includes the following weight parts component: chitosan 40~50 parts, activated carbon 20~40 parts, polystyrene sodium sulfonate 18~26 parts, polyethylene imine 4~18 parts, inorganic polymer flocculants 15~25 parts.Through above technical scheme, solve the problem of poor removal effect of water treatment agent in related art on CODcr and animal fat in slaughterhouse sewage.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, specifically to a method for treating wastewater from slaughterhouses and a water treatment agent. Background Technology

[0002] The main source of slaughterhouse wastewater is the series of wastewater discharged during the slaughtering process. This wastewater contains large amounts of blood, fat, meat scraps, and fur, and is high in organic pollutants and animal fats, especially CODcr and animal fats. High CODcr levels in slaughterhouse wastewater indicate excessive organic matter in the water, leading to water pollution after discharge. High CODcr levels also have toxic effects on aquatic organisms, causing them to die or migrate. Furthermore, animal fats are difficult to degrade in water, easily accumulating and leading to eutrophication, which affects the survival of aquatic life. Therefore, effective slaughterhouse wastewater treatment measures must be implemented to reduce CODcr and animal fat levels in the wastewater to protect the environment and human health.

[0003] In the process of treating slaughterhouse wastewater, water treatment agents are usually added to remove organic pollutants. However, the removal efficiency of currently used water treatment agents for organic matter in slaughterhouse wastewater needs improvement. Therefore, developing a water treatment agent that can effectively remove CODcr and animal fats from slaughterhouse wastewater is of great significance. Summary of the Invention

[0004] This invention proposes a method for treating slaughterhouse wastewater and a water treatment agent, which solves the problem that water treatment agents in related technologies have poor removal effects on CODcr and animal fat in slaughterhouse wastewater.

[0005] The technical solution of the present invention is as follows:

[0006] This invention proposes a water treatment agent, the raw materials of which include the following components in parts by weight:

[0007] Chitosan 40-50 parts, activated carbon 20-40 parts, sodium polystyrene sulfonate 18-26 parts, polyethyleneimine 4-18 parts, inorganic polymer flocculant 15-25 parts.

[0008] As a further technical solution, the weight ratio of sodium polystyrene sulfonate to polyethyleneimine is 2~4:1.

[0009] In this invention, when the weight ratio of sodium polystyrene sulfonate to polyethyleneimine is 2 to 4:1, the removal effect of water treatment agents on CODcr and animal fat in slaughterhouse wastewater can be further enhanced.

[0010] As a further technical solution, the activated carbon is modified activated carbon, and the raw materials of the modified activated carbon include activated carbon and ethyl hydroxynicotinic acid compounds.

[0011] In this invention, activated carbon is modified using ethyl hydroxynicotinate compounds. On the one hand, this makes the activated carbon easier to combine with other components in the water treatment agent to form a more stable water treatment agent. On the other hand, it enhances the adsorption activity of the activated carbon, enabling it to effectively capture and remove organic pollutants in slaughterhouse wastewater, and further enhances the removal effect of the water treatment agent on CODcr and animal fat in slaughterhouse wastewater.

[0012] As a further technical solution, the hydroxynicotinic acid ethyl ester compound is one or two of 2,4-dihydroxy-6-methylnicotinic acid ethyl ester and 4,6-dihydroxynicotinic acid ethyl ester, preferably 2,4-dihydroxy-6-methylnicotinic acid ethyl ester.

[0013] As a further technical solution, the weight ratio of activated carbon to ethyl hydroxynicotinic acid compound is 5~29:1.

[0014] When the weight ratio of activated carbon to ethyl hydroxynicotinate compounds is 5~29:1, the removal effect of water treatment agents on CODcr and animal fat in slaughterhouse wastewater can be further enhanced.

[0015] As a further technical solution, the preparation method of the modified activated carbon includes the following steps: dispersing the activated carbon evenly in dimethylformamide, adding the ethyl hydroxynicotinic acid compound, stirring, and drying to obtain the modified activated carbon.

[0016] As a further technical solution, the raw material for the modified activated carbon also includes sodium sulfite; the weight ratio of the ethyl hydroxynicotinate compound and the sodium sulfite is 1~5:1.

[0017] The inventors also discovered that introducing sodium sulfite during the modification of activated carbon using ethyl hydroxynicotinamide compounds, and then using both sodium sulfite and ethyl hydroxynicotinamide compounds to modify the activated carbon, can further enhance the removal efficiency of water treatment agents on CODcr and animal fats in slaughterhouse wastewater. The optimal removal efficiency is achieved only when the weight ratio of ethyl hydroxynicotinamide compounds to sodium sulfite is 1–5:1. The speculated reason is that the presence of sodium sulfite further enhances the binding effect between activated carbon and ethyl hydroxynicotinamide compounds, making it easier for them to bind with animal fats and other organic pollutants in slaughterhouse wastewater, thereby further enhancing the removal efficiency of water treatment agents on CODcr and animal fats in slaughterhouse wastewater.

[0018] As a further technical solution, the preparation method of the modified activated carbon includes the following steps:

[0019] A1. Dissolve the sodium sulfite in water to obtain a sodium sulfite solution, add the activated carbon to the sodium sulfite solution, stir evenly, and dry to obtain sodium sulfite modified activated carbon.

[0020] A2. Disperse the sodium sulfite-modified activated carbon evenly in dimethylformamide, and add the ethyl hydroxynicotinic acid compound to obtain modified activated carbon.

[0021] As a further technical solution, in step A1, the mass fraction of the sodium sulfite solution is 20%~27%.

[0022] As a further technical solution, the activated carbon is one or both of coconut shell activated carbon and wood activated carbon.

[0023] As a further technical solution, the inorganic polymeric flocculant is one or more of polyaluminum sulfate, polyaluminum chloride, and polyaluminum ferric silicate.

[0024] The present invention also proposes a method for preparing a water treatment agent, comprising the following steps: mixing the chitosan, activated carbon, sodium polystyrene sulfonate, polyethyleneimine, and inorganic polymeric flocculant in proportion to weight to obtain the water treatment agent.

[0025] The present invention also proposes a method for treating slaughterhouse wastewater, comprising the following steps: adding the aforementioned water treatment agent to the slaughterhouse wastewater and mixing it evenly.

[0026] The working principle and beneficial effects of this invention are as follows:

[0027] In this invention, the raw materials for the water treatment agent include chitosan, activated carbon, sodium polystyrene sulfonate, polyethyleneimine, and inorganic polymeric flocculants. Through the effective combination of these components, a structurally stable water treatment agent can be prepared. When used for slaughterhouse wastewater treatment, it can effectively reduce the CODcr and animal fat content in the wastewater. Specifically, the introduction of sodium polystyrene sulfonate and polyethyleneimine into the raw materials of the water treatment agent demonstrates their synergistic effect. By rationally controlling their weight ratio, they can effectively adsorb organic pollutants in slaughterhouse wastewater, effectively remove CODcr and animal fat content, and ultimately enhance the treatment effect of the water treatment agent on slaughterhouse wastewater. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0029] In the following examples and comparative examples, the degree of deacetylation of chitosan was 99%, and the model was PRS184521; the activated carbon used was coconut shell activated carbon with a particle size of 425 mesh and a specific surface area of ​​1500 m². 2 / g; Sodium polystyrene sulfonate has a weight-average molecular weight of 70,000 and a viscosity of 40 mPa‧s; Polyethyleneimine is of type BL3 and has a melt flow rate of 0.95 g / 10 min; Polyaluminum sulfate is selected as the inorganic polymer flocculant, with a mesh size of 60 and a type of JY650.

[0030] Example 1

[0031] A water treatment agent, the raw materials of which include the following components in parts by weight:

[0032] 40 parts chitosan, 20 parts activated carbon, 18 parts sodium polystyrene sulfonate, 4 parts polyethyleneimine, 15 parts polyaluminum sulfate;

[0033] A method for preparing a water treatment agent includes the following steps: mixing the above components evenly according to their weight parts to obtain the water treatment agent.

[0034] Example 2

[0035] A water treatment agent, the raw materials of which include the following components in parts by weight:

[0036] 45 parts chitosan, 30 parts activated carbon, 19 parts sodium polystyrene sulfonate, 11 parts polyethyleneimine, 20 parts polyaluminum sulfate;

[0037] A method for preparing a water treatment agent includes the following steps: mixing the above components evenly according to their weight parts to obtain the water treatment agent.

[0038] Example 3

[0039] A water treatment agent, the raw materials of which include the following components in parts by weight:

[0040] 50 parts chitosan, 40 parts activated carbon, 26 parts sodium polystyrene sulfonate, 18 parts polyethyleneimine, 25 parts polyaluminum sulfate;

[0041] A method for preparing a water treatment agent includes the following steps: mixing the above components evenly according to their weight parts to obtain the water treatment agent.

[0042] Example 4

[0043] The only difference between this embodiment and Embodiment 2 is that in this embodiment, 25 parts of sodium polystyrene sulfonate and 5 parts of polyethyleneimine are added.

[0044] Example 5

[0045] The only difference between this embodiment and Embodiment 2 is that in this embodiment, 20 parts of sodium polystyrene sulfonate and 10 parts of polyethyleneimine are added.

[0046] Example 6

[0047] The only difference between this embodiment and Embodiment 2 is that in this embodiment, 24 parts of sodium polystyrene sulfonate and 6 parts of polyethyleneimine are added.

[0048] Example 7

[0049] The only difference between this embodiment and Example 6 is that, in this embodiment, the activated carbon is modified activated carbon, and its preparation method includes the following steps: 24 parts of activated carbon are evenly dispersed in 15 parts of dimethylformamide, 6 parts of 2,4-dihydroxy-6-methylnicotinic acid ethyl ester are added, stirred, and dried to obtain modified activated carbon.

[0050] Example 8

[0051] The only difference between this embodiment and Example 7 is that in this embodiment, 29.5 parts of activated carbon and 0.5 parts of ethyl 2,4-dihydroxy-6-methylnicotinate are added.

[0052] Example 9

[0053] The only difference between this embodiment and Embodiment 7 is that, in this embodiment, 29 parts of activated carbon and 1 part of ethyl 2,4-dihydroxy-6-methylnicotinate are added.

[0054] Example 10

[0055] The only difference between this embodiment and Embodiment 7 is that, in this embodiment, 25 parts of activated carbon and 5 parts of ethyl 2,4-dihydroxy-6-methylnicotinate are added.

[0056] Example 11

[0057] The only difference between this embodiment and Embodiment 10 is that, in this embodiment, the preparation method of modified activated carbon includes the following steps:

[0058] A1. Dissolve 0.5 parts of sodium sulfite in water to obtain a sodium sulfite solution (mass fraction of 25%). Add 25 parts of activated carbon to the sodium sulfite solution, stir evenly, and dry to obtain sodium sulfite modified activated carbon.

[0059] A2. Disperse sodium sulfite-modified activated carbon evenly in 15 parts of dimethylformamide, and add 5 parts of ethyl 2,4-dihydroxy-6-methylnicotinate to obtain modified activated carbon.

[0060] Example 12

[0061] The only difference between this embodiment and Example 11 is that in this embodiment, 25 parts of activated carbon, 5 parts of ethyl 2,4-dihydroxy-6-methylnicotinate, and 6 parts of sodium sulfite are added.

[0062] Example 13

[0063] The only difference between this embodiment and Example 11 is that in this embodiment, 25 parts of activated carbon, 5 parts of ethyl 2,4-dihydroxy-6-methylnicotinate, and 5 parts of sodium sulfite are added.

[0064] Example 14

[0065] The only difference between this embodiment and Example 11 is that in this embodiment, 25 parts of activated carbon, 5 parts of ethyl 2,4-dihydroxy-6-methylnicotinate, and 1 part of sodium sulfite are added.

[0066] Comparative Example 1

[0067] The only difference between this comparative example and Example 1 is that in this comparative example, polyethyleneimine was not added, and 22 parts of sodium polystyrene sulfonate were added.

[0068] Comparative Example 2

[0069] The only difference between this comparative example and Example 1 is that sodium polystyrene sulfonate was not added in this comparative example, and 22 parts of polyethyleneimine were added.

[0070] Comparative Example 3

[0071] The only difference between this comparative example and Example 1 is that neither sodium polystyrene sulfonate nor polyethyleneimine was added in this comparative example.

[0072] Experimental Example

[0073] In a slaughterhouse wastewater pool measuring 10m × 10m × 3.5m, with an effective water depth of 3m, the CODcr content in the untreated slaughterhouse wastewater was determined according to the method in HJ 6828-2017. The method of 637-2018 was used to determine the animal fat content in slaughterhouse wastewater before treatment. The CODcr content was 693 mg / L and the animal fat content was 168 mg / L. The water treatment agents prepared in Examples 1-14 and Comparative Examples 1-2 were added to the slaughterhouse wastewater (addition ratio of 2 g / L), mixed evenly, and after 3 days, the CODcr content and animal fat content in the slaughterhouse wastewater after treatment with the water treatment agents were determined according to the above standard. The CODcr and animal fat removal rates were calculated according to the following formulas: CODcr removal rate (%) = (CODcr content before treatment - CODcr content after treatment) / CODcr content before treatment × 100%; Animal fat removal rate (%) = (Animal fat content before treatment - Animal fat content after treatment) / Animal fat content before treatment × 100%. The test results are shown in Table 1 below.

[0074] Table 1. Treatment results of slaughterhouse wastewater by water treatment agents in Examples 1-14 and Comparative Examples 1-3.

[0075]

[0076] Compared with Comparative Examples 1-3, the CODcr removal rate and animal fat removal rate of Example 1 were significantly improved, indicating that when sodium polystyrene sulfonate and polyethyleneimine are introduced into the raw materials of the water treatment agent, sodium polystyrene sulfonate and polyethyleneimine have a synergistic effect, which can effectively enhance the removal effect of water treatment agent on CODcr and animal fat in slaughterhouse wastewater.

[0077] Compared with Examples 2 and 4, Examples 5 and 6 showed improved CODcr removal rates and animal fat removal rates, indicating that when the weight ratio of sodium polystyrene sulfonate to polyethyleneimine is 2-4:1, the removal effect of water treatment agents on CODcr and animal fat in slaughterhouse wastewater can be further enhanced.

[0078] Compared with Example 6, the CODcr removal rate and animal fat removal rate of Examples 7-10 were improved, indicating that modifying activated carbon with ethyl hydroxynicotinic acid compounds can further enhance the removal effect of water treatment agents on CODcr and animal fat in slaughterhouse wastewater. Specifically, compared with Examples 7-8, the CODcr removal rate and animal fat removal rate of Examples 9-10 were improved, indicating that when the weight ratio of activated carbon to ethyl hydroxynicotinic acid compounds is 5-29:1, the removal effect of water treatment agents on CODcr and animal fat in slaughterhouse wastewater can be further enhanced.

[0079] Compared with Example 10, the CODcr removal rate and animal fat removal rate of Examples 11-14 were improved, indicating that modifying activated carbon with sodium sulfite and ethyl hydroxynicotinic acid compounds can further enhance the removal effect of water treatment agents on CODcr and animal fat in slaughterhouse wastewater. Compared with Examples 11-12, the CODcr removal rate and animal fat removal rate of Examples 13-14 were improved, indicating that when the weight ratio of ethyl hydroxynicotinic acid compounds to sodium sulfite is 1-5:1, the removal effect of water treatment agents on CODcr and animal fat in slaughterhouse wastewater can be further enhanced.

[0080] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A water treatment agent, characterized in that, The raw materials consist of the following components in parts by weight: Chitosan 40-50 parts, modified activated carbon 20-40 parts, sodium polystyrene sulfonate 18-26 parts, polyethyleneimine 4-18 parts, inorganic polymer flocculant 15-25 parts; The raw materials for the modified activated carbon include activated carbon and ethyl hydroxynicotinic acid compounds; The hydroxynicotinic acid ethyl ester compound is one or two of 2,4-dihydroxy-6-methylnicotinic acid ethyl ester and 4,6-dihydroxynicotinic acid ethyl ester. The weight ratio of activated carbon to ethyl hydroxynicotinic acid compounds is 5~29:1; The modified activated carbon also includes sodium sulfite as a raw material; the weight ratio of the ethyl hydroxynicotinate compound to the sodium sulfite is 1~5:1; The method for preparing the modified activated carbon includes the following steps: A1. Dissolve the sodium sulfite in water to obtain a sodium sulfite solution, add the activated carbon to the sodium sulfite solution, stir evenly, and dry to obtain sodium sulfite modified activated carbon. A2. Disperse the sodium sulfite-modified activated carbon evenly in dimethylformamide, and add the ethyl hydroxynicotinic acid compound to obtain modified activated carbon.

2. A water treatment agent according to claim 1, characterized in that, The weight ratio of sodium polystyrene sulfonate to polyethyleneimine is 2~4:

1.

3. The water treatment agent according to claim 1, characterized in that, The activated carbon is one or both of coconut shell activated carbon and wood-based activated carbon; and / or The inorganic polymeric flocculant is one or more of polyaluminum sulfate, polyaluminum chloride, and polyaluminum ferric silicate.

4. A method for treating wastewater from slaughterhouses, characterized in that, Includes the following steps: The water treatment agent described in any one of claims 1 to 3 is added to the wastewater from the slaughterhouse and mixed evenly.

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