Application method of flocculating agent

Abstract

The application method of the flocculating agent is characterized by comprising the following steps: starting to store water in a Fenton intermediate water tank, adding sulfuric acid, and pretreating the pH value of Fenton before water feeding; pumping water in the middle water tank into the Fenton tower by using a water pump, and filling the Fenton tower with water; hydrogen peroxide and a ferrous sulfate solution are added according to a specified proportion, and a circulating pump is started for rapid mixing reaction; the reaction efficiency is optimal when the reaction PH is adjusted to 3.5-4.5; after the reaction, discharging water to a degassing tank, and continuously aerating in the degassing tank, so that residual gas after the Fenton reaction is removed; the high positive charge density of the polyaluminum chloride inorganic coagulant aid and the bridging effect of the PAM organic flocculant are utilized to generate a synergistic effect, so that the flocculation treatment capacity is improved, fine flocs in the Fenton degassing tank are tightly combined by adsorbed flocs, and the effluent turbidity is reduced; according to the invention, the turbidity of the drained water after Fenton treatment is improved, the economic operation cost is reduced, and the environmental protection risk is also reduced.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to an application method of a flocculant. Background Art

[0002] In sewage treatment, the most economical and efficient chemical treatment method is the Fenton reaction. Because the Fenton reaction reagents are hydrogen peroxide and ferrous sulfate, the treated water is a turbid mixture, which requires the addition of flocculants after the Fenton reaction to ensure the clarity of the effluent. The traditional flocculant is polyacrylamide, but the flocculation treatment capacity of polyacrylamide is insufficient when it is used. Therefore, the dosage of polyacrylamide needs to be increased, which will cause waste. In order to solve the above problems, a flocculant application method is proposed. Summary of the invention

[0003] In view of the above technical problems, the present invention provides a method for applying a flocculant, which is characterized by comprising the following steps:

[0004] 1. The Fenton intermediate water tank begins to store water and add sulfuric acid to pre-treat the pH of the Fenton water;

[0005] 2. Use a water pump to pump the water in the middle water pool into the Fenton tower and fill the Fenton tower with water;

[0006] 3. Add hydrogen peroxide and ferrous sulfate solution in the prescribed proportion, and start the circulation pump to use it for rapid mixing reaction; the reaction pH is adjusted to between 3.5-4.5 for the best reaction efficiency;

[0007] 5. After the reaction, the effluent is sent to the degassing tank, and aeration is continuously added to the degassing tank to remove the residual gas after the Fenton reaction;

[0008] 6. Add liquid alkali to adjust the pH to between 6.0-6.5 to meet the discharge standard;

[0009] 7. Add polyacrylamide aqueous solution to make the mixed liquid in the degassing tank initially form flocculation, and then add polyaluminium chloride solution to further flocculate the flocculation to form compact flocs, thus accelerating its precipitation;

[0010] 8. After sedimentation, it flows to the sedimentation tank, the clean water flows out from the overflow port, and the sludge at the bottom is pumped to the sludge tank for further treatment through the sludge pump;

[0011] The system includes intermediate effluent, a Fenton tower, a degassing tank, a final settling tank, a lifting pump, and a circulating pump; the chemical auxiliary materials used are sulfuric acid, liquid alkali, ferrous sulfate, hydrogen peroxide, polyacrylamide, and polyaluminium chloride; and the various tanks are connected by water pumps and pipelines.

[0012] Beneficial effects of the present invention:

[0013] The sewage of the present invention is added with polyaluminium chloride as a coagulant in a Fenton degassing tank, which is compounded with the original PAM for use, and the high positive charge density of the polyaluminium chloride inorganic coagulant and the bridging effect of the PAM organic flocculant are used to produce a synergistic effect, thereby improving the flocculation treatment capacity, and making the fine flocs in the Fenton degassing tank be adsorbed and the flocs are tightly combined, thereby reducing the turbidity of the effluent water; the present invention improves the turbidity of the drainage after the Fenton treatment, reduces the economic operation cost, and also reduces the environmental protection risk. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the implementation effect of Example 2 of a flocculant application method of the present invention. DETAILED DESCRIPTION

[0015] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0017] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0018] Example 1

[0019] The present invention provides a flocculant application method, which is characterized by comprising the following steps:

[0020] 1. The Fenton intermediate water tank begins to store water and add sulfuric acid to pre-treat the pH of the Fenton water;

[0021] 2. Use a water pump to pump the water in the middle water pool into the Fenton tower and fill the Fenton tower with water;

[0022] 3. Add hydrogen peroxide and ferrous sulfate solution in the prescribed proportion, and start the circulation pump to use it for rapid mixing reaction; the reaction pH is adjusted to between 3.5-4.5 for the best reaction efficiency;

[0023] 5. After the reaction, the effluent is sent to the degassing tank, and aeration is continuously added to the degassing tank to remove the residual gas after the Fenton reaction;

[0024] 6. Add liquid alkali to adjust the pH to between 6.0-6.5 to meet the discharge standard;

[0025] 7. Add polyacrylamide aqueous solution to make the mixed liquid in the degassing tank initially form flocculation, and then add polyaluminium chloride solution to further flocculate the flocculation to form compact flocs, thus accelerating its precipitation;

[0026] 8. After sedimentation, it flows to the sedimentation tank, the clean water flows out from the overflow port, and the sludge at the bottom is pumped to the sludge tank for further treatment through the sludge pump;

[0027] The system includes intermediate effluent, a Fenton tower, a degassing tank, a final settling tank, a lifting pump, and a circulating pump; the chemical auxiliary materials used are sulfuric acid, liquid alkali, ferrous sulfate, hydrogen peroxide, polyacrylamide, and polyaluminium chloride; and the various tanks are connected by water pumps and pipelines.

[0028] Example 2

[0029] Polyaluminium chloride is added as a coagulant in the Fenton degassing tank, and used in combination with the original PAM. The high positive charge density of the inorganic polyaluminium chloride coagulant and the bridging effect of the PAM organic flocculant produce a synergistic effect, which improves the flocculation treatment capacity and makes the fine flocs in the Fenton degassing tank tightly combined, thereby reducing the turbidity of the effluent.

[0030] Through computer data tracking, the turbidity of drainage water has been reduced after the use of polyaluminium chloride. The turbidity was 4 before and 0.5 after use. The dosage of polyaluminium chloride is 125-150PPM, the daily dosage is 4.5 tons, and the cost of treating a ton of sewage water increases by about 0.05 yuan. In addition, polyacrylamide is reduced by 0.15 tons per day, and the cost of treating a ton of sewage water is reduced by about 0.1 yuan. The comprehensive economic indicator per ton of water saves 0.05 yuan.

[0031] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. The various components mentioned in the present invention are common technologies in the existing field. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only to illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for applying a flocculant, characterized in that: The following steps are involved:

1. The Fenton intermediate water tank begins to store water and add sulfuric acid to pre-treat the pH of the Fenton water; 2. Use a water pump to pump the water in the middle water pool into the Fenton tower and fill the Fenton tower with water; 3. Add hydrogen peroxide and ferrous sulfate solution in the prescribed proportion, and start the circulation pump to use it for rapid mixing reaction; 5. After the reaction, the effluent is sent to the degassing tank, and aeration is continuously added to the degassing tank to remove the residual gas after the Fenton reaction; 6. Liquid alkali is added to reach the discharge standard PH; 7. Add polyacrylamide aqueous solution to make the mixed liquid in the degassing tank initially form flocculation, and then add polyaluminium chloride solution to further flocculate the flocculation to form compact flocs, thus accelerating its precipitation; 8. After sedimentation, it flows to the sedimentation tank, and the clean water flows out from the overflow port. The sludge at the bottom is pumped into the sludge tank for further treatment through the sludge pump.

2. The method for applying a flocculant according to claim 1, characterized in that: The hydrogen peroxide and ferrous sulfate in step 3 are used to adjust the pH to between 3.5 and 4.

5.

3. The method for applying a flocculant according to claim 1, characterized in that: In step 6, liquid caustic soda is added to adjust the pH to between 6.0 and 6.

5.

4. A flocculant according to any one of claims 1 to 3, characterized in that: It is composed of polyacrylamide and polyaluminium chloride, with the mass ratio of polyacrylamide being 30 parts and polyaluminium chloride being 2 parts.

5. A flocculant according to claim 4, characterized in that: The aqueous solution of polyaluminium chloride is 125-150PPM, and the aqueous solution of polyacrylamide is 100-200PPM.

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