Sewage and wastewater treatment agent and application thereof

Abstract

The invention relates to the technical field of sewage and wastewater treatment, in particular to a sewage and wastewater treatment agent and application thereof. The sewage and wastewater treating agent is prepared from the following raw materials in parts by mass: 30 to 60 parts of attapulgite, 20 to 50 parts of polyacrylamide and 20 parts of ferric salt. The sewage and wastewater treating agent can be suitable for various sewage and wastewater, flocculation alumen ustum is large, the settling speed is high, a large number of tiny-molecule suspended solids are adsorbed, and the water quality of a clear water layer is clear. The device can be widely applied to municipal sewage treatment and coal washing treatment of coal washing plants.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage and wastewater treatment, and particularly relates to a sewage and wastewater treatment agent and its application. Background Art

[0002] The most common flocculants on the market at present are mainly polyacrylamide (PAM). PAM was first prepared by reacting acryloyl chloride with ammonia by Moureu in 1893 and was first commercially produced in the United States in 1954. However, the current flocculants generally have the defects of small flocculant flocs and slow sedimentation speed. Therefore, it is of great significance to provide a sewage and wastewater treatment agent made of nanomaterials to increase the flocculant flocs and improve the sedimentation speed in the technical field of sewage and wastewater treatment. Summary of the Invention

[0003] Based on the above, the present invention provides a sewage and wastewater treatment agent and its application. Applying the sewage and wastewater treatment agent of the present invention to sewage and wastewater treatment has the advantages of large flocculant flocs and fast sedimentation speed.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] One of the technical solutions of the present invention is a sewage and wastewater treatment agent, which, by mass, comprises: 30-60 parts of attapulgite, 20-50 parts of polyacrylamide, and 20 parts of iron salt.

[0006] Another technical solution of the present invention is the application of the sewage and wastewater treatment agent in sewage and wastewater treatment.

[0007] Another technical solution of the present invention is a sewage and wastewater treatment method, which comprises adding the sewage and wastewater treatment agent into water and stirring to obtain a sewage and wastewater treatment agent solution;

[0008] adding the sewage and wastewater treatment agent solution to the sewage and wastewater, mixing evenly, and then standing still.

[0009] The present invention discloses the following technical effects:

[0010] The sewage and wastewater treatment agent of the present invention is applicable to various sewage and wastewater, has large flocculant flocs and fast sedimentation speed, a large number of extremely small molecular suspended substances are adsorbed, the water quality of the clear water layer is clear, it has an obvious effect on acidic and alkaline water quality, there is no need to add acid and alkali adjusting aids, the use cost is reduced, and the time cost and labor cost are saved. It can be widely applied to municipal sewage treatment and coal washing treatment in coal washing plants. Description of the Drawings

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for use in the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0012] Figure 1 This is the test report for the sewage and wastewater treatment agent prepared in Example 1 of the present invention, which was entrusted to a third party for testing. Detailed implementation manners

[0013] Now, various exemplary implementation manners of the present invention will be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, characteristics, and implementation schemes of the present invention.

[0014] It should be understood that the terms used in the present invention are only for describing specific implementation manners and are not used to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded from the range.

[0015] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0016] Without departing from the scope or spirit of the present invention, various improvements and changes can be made to the specific implementation manners of the present invention specification, which are obvious to those skilled in the art. Other implementation manners obtained from the present invention specification are obvious to those skilled in the art. The present invention specification and embodiments are only exemplary.

[0017] Regarding the terms "comprising", "including", "having", "containing", etc. used herein, they are all open-ended terms, meaning including but not limited to.

[0018] The "%" mentioned in the present invention represents mass percentage unless otherwise specified.

[0019] The sewage and wastewater treatment agent of the present invention can be used for water purification, industrial wastewater, and treatment of special water quality, such as sediment sewage, aquaculture sewage, municipal sewage, printing and dyeing sewage, papermaking sewage, smelting sewage, sewage with high heavy metal content, etc.

[0020] The mechanism of action of the sewage treatment agent of the present invention is: the introduction of organic (polyacrylamide) and inorganic modifiers (attapulgite), and amphoteric "green" molecular modifiers (iron salts) can achieve the double electric layer structure regulation of the attapulgite surface, enhance the interaction between molecules, and improve the stability between molecules. The sewage treatment agent of the present invention can perform ion exchange, adsorption, bonding and agglomeration of microparticles in sewage and wastewater, thereby forming flocculent precipitation; through the compression of the double electric layer, electrical neutralization, adsorption bridge and other effects, net capture and sweeping (attapulgite itself has a layered chain structure, is a hydrated magnesium-aluminum silicate clay, not only has surface active centers, in addition to adsorption, but also has catalytic effects), so that the attractive potential energy between colloidal particles exceeds the repulsive potential energy, so that the dispersed colloid particles are clustered into flocculents and precipitated, and solid-liquid separation is achieved.

[0021] The first aspect of the present invention provides a sewage and wastewater treatment agent, wherein the raw materials include, by weight, 30-60 parts of attapulgite, 20-50 parts of polyacrylamide and 20 parts of iron salt.

[0022] In a preferred embodiment of the present invention, the iron salt is polyferric sulfate.

[0023] The present invention adopts attapulgite to replace the coagulant effect of traditional polyaluminium chloride, which can adsorb more small molecules that are not easily adsorbed by flocculants, thereby improving the treatment efficiency and effect.

[0024] In practical applications, in order to avoid the problem that the particle size of the sewage treatment agent is too small to be evenly dispersed in water, it can be tableted. The specific tableting method is a conventional technical means in the field and is not the focus of patent protection of this invention, so it will not be described here.

[0025] Attapulgite: Attapulgite is a natural nano-scale hydrated magnesium-aluminum silicate clay mineral with a 2:1 layered chain structure. It has a nanorod crystal morphology, a regular nanopore structure and surface active silanol groups. It has a large specific surface area and excellent physical and chemical properties. It has a wide range of applications and is green and environmentally friendly.

[0026] The basic characteristics of attapulgite include the following: First, the special charge distribution. 2 O、Al 2The amphoteric hydroxyl group (OH) on ROH generated by the bond breaking of O and MgO enables attapulgite to act as an anion and cation adsorbent respectively in different pH environments. The special charge distribution also endows attapulgite with excellent colloidal properties and water suspension properties, making it applicable to oilfield circulating drilling mud, suspending agent, synthetic printing paste, coating additive, thixotropic agent, etc.; Second, a large specific surface area. The specific surface area of attapulgite can reach 150-210 m 2 / g. In water treatment applications, attapulgite can adsorb a variety of heavy metal ions (such as: Pb 2+ , Cd 2+ , and Cr 3+ , etc.), radioactive metal ions (uranium and actinides, etc.), dyes (including cationic dyes and anionic dyes, etc.), phenolic substances, etc.; Third, a rich pore structure. Attapulgite has a rich pore structure at the nanoscale, and these pore structures can carry out physical adsorption and chemical adsorption simultaneously. This property endows attapulgite with certain catalytic performance and can also be used as an excellent catalyst carrier. From the above introduction, due to its natural chain-layer crystal structure, attapulgite has outstanding physical and chemical properties such as adsorption, fluidity, and nanostructure. Among them, the excellent adsorption performance is the focus of attention and research by scholars at home and abroad. The direct application of natural attapulgite in the adsorption field still has certain limitations.

[0027] Iron salts: Iron salts refer to salts containing iron ions (Fe 3+ ). Polymerized ferric salts are a new type of water purifying agent, mainly used for the purification of tap water and industrial water supply, and are the first choice of agents that can fully meet the requirements of the new national drinking water hygiene specifications; at the same time, in the treatment of various industrial wastewaters and domestic sewage, in terms of its cost performance, it is superior to traditional aluminum salt agents in most water bodies. Using iron salts for wastewater treatment has the following advantages: 1. Good coagulation performance, many and dense flocs, fast flocculation and sedimentation speed, dense flocs, and less sludge volume. 2. The purified water quality is good, without aluminum, chlorine, and other harmful heavy metal ions, no iron ion transfer in the water phase, the water body does not turn yellow, non-toxic and harmless, and completely reliable. 3. It has obvious effects of decolorization, turbidity removal, deodorization, algae removal, removal of COD, BOD, and various harmful heavy metal ions. 4. When treating low-temperature, low-turbidity, slightly polluted, and high-turbidity raw water, its purification effect is significantly better than traditional aluminum salt agents, and the agent cost is about 20% lower than that of aluminum salt agents. 5. It has a wide pH value range for adapting to water bodies (4-11, the best is 6-9), and the change range of the pH value and total alkalinity of the purified water body is small. 6. In sludge dewatering, it can completely replace ferric oxide and other inorganic salt agents; when used in combination with polyacrylamide, the solid-liquid separation is rapid, the sludge is easy to peel off, and the sludge moisture content is low, which can significantly reduce the sludge dewatering cost.

[0028] In a preferred embodiment of the present invention, by mass parts, the raw materials include: 50 parts of attapulgite, 30 parts of polyacrylamide, and 20 parts of iron salt.

[0029] The second aspect of the present invention provides the application of the sewage and wastewater treatment agent in the treatment of sewage and wastewater.

[0030] In a preferred embodiment of the present invention, the sewage and wastewater is slime water.

[0031] The third aspect of the present invention provides a method for treating sewage and wastewater (slime water). Add the sewage and wastewater treatment agent into water and stir to obtain a sewage and wastewater treatment agent solution.

[0032] Add the sewage and wastewater treatment agent solution to the sewage and wastewater, mix well, and then let it stand.

[0033] In some embodiments of the present invention, it can be mixed evenly by stirring or shaking. The time of stirring or shaking is 5 - 8 seconds. During the stirring or shaking process, molecules interact with each other to form flocculent masses. After stopping shaking or stirring and letting it stand, the masses will settle immediately.

[0034] When preparing the sewage and wastewater treatment agent solution, the water is clean water, such as tap water. The clean water cannot be deionized water for the following reasons: Deionized water removes mineral ions such as sodium, calcium, iron, and copper, while water treatment materials need the action of other some ions (such as sodium, calcium, iron, copper) during the dissolution process. And in actual production, the on-site environment cannot reach the experimental standard, and the water quality situation is more complex, so it is necessary to adapt to the on-site environment as much as possible.

[0035] In a preferred embodiment of the present invention, the mass ratio of the sewage and wastewater treatment agent to the water is 0.1:100. The specific stirring is to stir at a rotation speed of 450 r / min until there are no lumps in the solution.

[0036] During the actual preparation process, the rotation speed of stirring can be adjusted adaptively according to the actual situation.

[0037] In a preferred embodiment of the present invention, the addition amount of the sewage and wastewater treatment agent solution is 0.2 - 0.4 ml / 100 ml of sewage and wastewater.

[0038] In a preferred embodiment of the present invention, the standing time is 8 s - 45 min.

[0039] During the actual preparation process, the rotation speed of stirring can be adjusted adaptively according to the actual situation.

[0040] The technical solutions of the present invention, unless otherwise specified, are all conventional solutions in the art. The reagents or raw materials used, unless otherwise specified, are all purchased from commercial channels or have been made public.

[0041] In the examples and comparative examples of the present invention, the particle size of the attapulgite used is 600 mesh.

[0042] In the examples and comparative examples of the present invention, the polyacrylamide used is white granular, anionic, with a molecular weight of 20 million, a solid content of more than 88%, a hydrolysis degree of 26%, and a pH value of 6.

[0043] The iron salt used in the examples and comparative examples of the present invention is polyferric sulfate: with a concentration of 11%, a pH value (1% aqueous solution) of 2.2, an insoluble matter content of 0.5%, a total iron content of 18.5%, a basicity of 11%, a reducing substance (calculated as Fe 2+ content) of 0.10%, and a relative density of 2.44.

[0044] The tap water is used as the clear water in the examples of the present invention.

[0045] The sewage and wastewater treatment agent of the present invention has the advantages of fast sedimentation speed, strong adsorption capacity, and being green, environmentally friendly and pollution-free.

[0046] The technical solutions provided by the present invention will be described in detail below in conjunction with the examples, but they should not be construed as limiting the protection scope of the present invention.

[0047] Example 1

[0048] A sewage and wastewater treatment agent: calculated by mass, the raw materials are composed of 50 parts of attapulgite, 30 parts of polyacrylamide, and 20 parts of iron salt.

[0049] Preparation of the sewage and wastewater treatment agent solution: The steps are as follows:

[0050] Step 1, add 200 ml of clear water into a clean beaker and place it on a stirrer.

[0051] Step 2, under stirring conditions, slowly add the above sewage and wastewater treatment agent into the clear water according to the mass ratio of the sewage and wastewater treatment agent to the clear water of 0.1:100; wherein, the stirring speed is 450 r / min and the stirring time is 45 min; after the stirring ends, there are no visible lumps in the solution, and a sewage and wastewater treatment agent solution is obtained.

[0052] The test report of the sewage and wastewater treatment agent prepared in this example entrusted to a third party for testing is as Figure 1 shown.

[0053] Comparative Example 1

[0054] The difference from Example 1 is only that the sewage and wastewater treatment agent is polyacrylamide.

[0055] Comparative Example 2

[0056] The difference from Example 1 is only that, by mass parts, the raw materials of the sewage and wastewater treatment agent are composed of 40 parts of attapulgite, 40 parts of polyacrylamide, and 20 parts of iron salt.

[0057] Comparative Example 3

[0058] The difference from Example 1 is only that, by mass parts, the raw materials of the sewage and wastewater treatment agent are composed of 60 parts of attapulgite, 20 parts of polyacrylamide, and 20 parts of iron salt.

[0059] Comparative Example 4

[0060] The difference from Example 1 is only that, by mass parts, the raw materials of the sewage and wastewater treatment agent are composed of 30 parts of palygorskite, 50 parts of polyacrylamide, and 20 parts of iron salt.

[0061] Effect Example 1

[0062] The sewage and wastewater treatment agents prepared in Example 1 and Comparative Examples 1-8 were subjected to effect verification as follows:

[0063] Prepare the same test tubes and label them as groups A, B, C, D, and E, with three replicates in each group, and measure the average value; add the same amount of slime water sample (100 ml) to the above test tubes. The slime water sample has a slime content of 40 g / L, an ash content of 58.87%, and a pH value of 3.0. The addition method is as follows: Stir the slime water sample thoroughly, add it to the 50 ml mark of test tube A, stir the slime water sample again, add it to the 50 ml mark of test tube B, stir the slime water sample again, add it to the 50 ml mark of test tube C, and so on until 50 ml of the slime water sample is added to test tube E. Then continue to stir the slime water sample thoroughly and add it to the 100 ml mark of test tube A, and then stir the slime water sample again and add it to the 100 ml mark of test tube B, and so on until it is added to the 100 ml mark of test tube E. The purpose of this addition method is to keep the slime water sample in the test tubes the same, making the experimental data more accurate and the phenomenon more obvious.

[0064] Add 0.2 ml of the sewage and wastewater treatment agent solution prepared in Example 1 to test tube A, add 1 g of the sewage and wastewater treatment agent in Comparative Example 1 to test tube B, and add 0.2 ml of the sewage and wastewater treatment agent solutions prepared in Comparative Examples 2-4 to test tubes C-E in sequence. Stir well, let stand, observe the flocculation state of the slime, compare the slime sedimentation speed, the height of the clear water layer after sedimentation is completed, and the turbidity, and finally compare the slime moisture content. The results are shown in Table 1:

[0065] Table 1

[0066]

[0067] Effect Example 2

[0068] The same effect verification as in Effect Example 1 was carried out, with the only difference being that the effect verification was only carried out on the sewage and wastewater treatment agent solution prepared in Example 1. The pH of the sewage and wastewater (coal slime water sample) in the test tube was 4.6 (from the northern Shaanxi region) and 9.2 (from the Shanxi region) to verify the treatment effect of the sewage and wastewater treatment agent solution prepared in Example 1 on acidic and alkaline sewage and wastewater. The results are as follows:

[0069] When the pH of the sewage and wastewater was 4.6, the sedimentation rate was 9 s, the height of the clear water layer was 93 mL, the moisture content of the coal slime was 7%, and the flocculation state: the flocs were compact and not easily dispersed.

[0070] When the pH of the sewage and wastewater was 9.2, the sedimentation rate was 10 s, the height of the clear water layer was 94 mL, the moisture content of the coal slime was 6%, and the flocculation state: the flocs were compact and not easily dispersed.

[0071] Effect Example 3

[0072] The same effect verification as in Effect Example 1 was carried out on Comparative Examples 3 and 4, with the only difference being that the amount of the sewage and wastewater treatment agent solution added to the test tube was adjusted from 0.2 ml to 0.4 ml.

[0073] The results show that when the addition amount of the sewage and wastewater treatment agent solution in Comparative Examples 3 and 4 was 0.4 ml, the sedimentation rate was comparable to that when the addition amount of the sewage and wastewater treatment agent solution in Example 1 was 0.2 ml. Only in terms of the addition amount, to achieve a sedimentation rate comparable to that of Example 1 in Comparative Examples 3 and 4, the addition amount of their sewage and wastewater treatment agent needs to be twice that of Example 1.

[0074] Effect Example 4

[0075] The sewage and wastewater treatment agent solution prepared in Example 1 was used in the coal washing plant of Xiangshuihe Mining Co., Ltd. in Shenmu City, Shaanxi Province. Compared with the water treatment agent used in the original plant (a mixture of polyaluminum chloride (PAC) and PAM with a mass ratio of 1:1), for the same volume of the solution and the same dosage of the water treatment agent, the dosing duration of the sewage and wastewater treatment agent prepared in Example 1 could reach 40 - 45 minutes, while the dosing duration of the water treatment agent used in the original plant was 20 - 25 minutes. From the perspective of the reaction time, the sewage and wastewater treatment agent of the present invention has great advantages in the timeliness of coal washing; from the perspective of each parameter of the coal washing water, the clear water layer corresponding to the sewage and wastewater treatment agent of the present invention can reach 1.8 meters, while the clear water layer corresponding to the water treatment agent used in the original plant is 1.6 meters. The height of the clear water layer also reflects the amount of moisture content. The lower the moisture content, the better the precipitation effect and the better the compaction effect of the coal slime.

[0076] The embodiments described above are only descriptions of the preferred embodiments of the present invention and do not limit the scope of the present invention. Without departing from the spirit of the present invention's design, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A sewage and wastewater treatment agent, characterized in that: Calculated by weight, the raw materials include: 30-60 parts of attapulgite, 20-50 parts of polyacrylamide and 20 parts of iron salt.

2. The sewage and wastewater treatment agent according to claim 1, characterized in that: The iron salt is polyferric sulfate.

3. The sewage and wastewater treatment agent according to claim 1, characterized in that: Calculated by weight, the raw materials include: 50 parts of attapulgite, 30 parts of polyacrylamide and 20 parts of iron salt.

4. Use of the sewage and wastewater treatment agent according to any one of claims 1 to 3 in sewage and wastewater treatment.

5. The use according to claim 4, characterized in that: The wastewater is coal sludge water.

6. A method for treating wastewater, characterized in that: Adding the sewage and wastewater treatment agent according to any one of claims 1 to 3 into water and stirring to obtain a sewage and wastewater treatment agent solution; The wastewater treatment agent solution is added to the wastewater, mixed and then allowed to stand.

7. The method for treating wastewater according to claim 6, characterized in that: The mass ratio of the sewage and wastewater treatment agent to the water is 0.1:100; the stirring is specifically stirring at a speed of 450 r / min until there are no lumps in the solution.

8. The method for treating wastewater according to claim 6, characterized in that: The addition amount of the wastewater treatment agent solution is 0.2-0.4 ml / 100 ml of wastewater.

Images