CN111732234A - A kind of treatment system and method for high suspended solids mine water as circulating water make-up water in power plant - Google Patents

Abstract

The invention discloses a treatment system and a method for taking highly suspended substance mine water as circulating water replenishing water of a power plant, wherein a water outlet of a mine water incoming pipe is communicated with an inlet of a high-efficiency flocculation tank through an oil skimming pre-settling regulation tank, an outlet of a coagulant dosing device and an outlet of a coagulant aid dosing device are communicated with a dosing port of the high-efficiency flocculation tank, an outlet of the high-efficiency flocculation tank is communicated with an inlet of an inclined-tube clarification tank, a supernatant outlet of the inclined-tube clarification tank is communicated with an inlet of a gravity valveless filter tank, an outlet of the gravity valveless filter tank and an outlet of a bactericide dosing device are communicated with an inlet of a clear water tank, and an outlet of the clear water tank is communicated with a water inlet of a cooling tower.

Description

A kind of treatment system and method for high suspended solids mine water as circulating water make-up water in power plant

technical field

The invention belongs to the technical field of wastewater treatment, and relates to a treatment system and method for using high suspended solids mine water as circulating water replenishment water in power plants.

Background technique

The Action Plan for the Prevention and Control of Water Pollution (Guo Fa [2015] No. 17) proposes to promote the comprehensive utilization of mine water. Mine water should be preferentially used for supplementary water in coal mining areas, production and ecological water in surrounding areas, and the recycling of coal washing wastewater should be strengthened. In addition, the Development Plan for Mine Water Utilization (Fa Gai Huan Zi [2013] No. 118) requires that the goal of improving the utilization rate of mine water is to adhere to the policy of overall planning, adapting measures to local conditions, taking into consideration overall planning and effective utilization, strengthening policy guidance, and promoting mine water. The construction of water purification and treatment projects will promote the industrialization of mine water utilization. According to the statistics of the National Development and Reform Commission, the current utilization rate of mine water in my country is only about 26%, and a large amount of mine water cannot be effectively used, which not only wastes water resources, but also pollutes the ecological environment with weak minerals.

Effective treatment of mine water and at the same time resource utilization is an effective measure to improve the ecological environment of the mining area, and it is also an important method to alleviate the shortage of water resources in the mining area, and an important measure to ensure the positive development of the mining industry. Especially for coal-electricity integrated enterprises, the circulating water system is a major water user in the power plant. After the mine water is treated, it is reused for the circulating water in the power plant to make up the water, and the waste can be turned into treasure, which is in line with the requirements of the national environmental protection policy. The sources of mine water mainly include slime wastewater from coal preparation plants, groundwater gushing water, and oily sewage from machine repair rooms and garages. Mine water is mainly polluted by underground personnel activities and mining. The water contains a certain amount of coal dust and rock dust. ～600mg/L, and contains some oil substances and organic pollutants, direct reuse does not meet the requirements of circulating water replenishment.

Therefore, it is necessary to design a system, the system and method can remove the suspended solids and chromaticity in the mine water, so that it can meet the requirements of circulating water replenishment.

SUMMARY OF THE INVENTION

The object of the present invention is to overcome the shortcomings of the above-mentioned prior art, and to provide a high suspended solids mine water as a treatment system and method for making up circulating water in a power plant. Hydration requirements.

In order to achieve the above purpose, the high suspended solids mine water treatment system of the present invention as the circulating water replenishment water of the power plant includes a mine water inlet pipe, an oil skimming pre-sedimentation adjustment tank, a coagulant dosing device, a coagulant aid dosing device, a high-efficiency flocculation tank, inclined tube clarifier, gravity valveless filter, bactericide dosing device, clear water tank and cooling tower;

The outlet of the mine water inlet pipe is connected with the inlet of the high-efficiency flocculation tank through the oil skimming pre-sedimentation adjustment tank. The outlet of the high-efficiency flocculation tank is connected with the inlet of the inclined tube clarifier, the supernatant outlet of the inclined tube clarifier is connected with the inlet of the gravity valveless filter, the outlet of the gravity valveless filter and the outlet of the bactericide dosing device It is connected with the inlet of the clean water pool, and the outlet of the clean water pool is connected with the water inlet of the cooling tower.

The oil skimming pre-settling adjustment tank and the high-efficiency flocculation tank are connected by a raw water lift pump. The oil skimming pre-sedimentation adjustment tank is equipped with a truss-type mud scraper, an oil scraper and an oil collecting pipe.

The tank body of the high-efficiency flocculation tank is divided into a first reaction zone and a second reaction zone by a partition plate, wherein the first reaction zone is communicated with the coagulant dosing device, and the second reaction zone is communicated with the coagulation aid dosing device.

The inclined tube clarifier adopts up-flow out-of-phase flow. The length of the inclined tube in the inclined tube clarifier is 1-1.2m, the vertical net distance is 0.8-1m, the inclination angle is 60°, the water retention time is 40-60min, and the inclined tube clarifier is 40-60min. The tube clarifier adopts gravity sludge discharge.

The sludge discharge port of the oil skimming pre-sedimentation adjustment tank, the sludge discharge port of the high-efficiency flocculation tank and the sludge discharge port of the inclined tube clarifier are all connected with the inlet of the slime concentration tank, and the supernatant liquid outlet of the slime concentration tank is connected with the oil skimmer. The water inlets of the pre-sedimentation adjustment tank are communicated with each other.

The slime outlet of the slime concentration tank is communicated with the inlet of the filter press through the sludge discharge pump.

The backwash water outlet of the gravity valveless filter tank is connected with the water inlet of the oil skimming pre-sedimentation adjustment tank. The gravity valveless filter tank is provided with anthracite, quartz sand double-layer filter material and supporting layer from top to bottom.

The clean water pool and the cooling tower are connected through a reuse water pump.

The outlet of the water quality stabilizer dosing device is communicated with the dosing device interface of the water replenishment main pipe of the cooling tower, and the outlet of the sulfuric acid dosing device is communicated with the sulfuric acid dosing port of the tower pool in the cooling tower.

The processing method of the high suspended solids mine water of the present invention as the circulating water replenishment water of the power plant comprises the following steps:

Using a high-efficiency flocculation tank and adding coagulants and coagulants, the suspended impurities with small particle size that are difficult to settle in the mine water are destabilized to form larger flocs, and then the solid-liquid separation is carried out through the inclined tube clarifier. The effluent of the clarifier goes through the gravity valveless filter to further remove the suspended solids, chromaticity and macromolecular organic matter in the water to ensure that the suspended solids in the effluent are ≤10mg/L.

The present invention has the following beneficial effects:

The high-suspension mine water of the present invention is used as a treatment system and method for making up circulating water in a power plant. In the specific operation, a high-efficiency flocculation tank is used and a coagulant and a coagulant are added to make the mine water difficult to settle and the particle size is small. After the suspended impurities are destabilized, they form large flocs, and then go through the inclined tube clarifier for solid-liquid separation. Suspended solids ≤10mg/L, meeting the relevant requirements of open circulating water cooling water supplementary water. A bactericide dosing device is installed at the entrance of the clear water tank to sterilize the effluent of the gravity valveless filter, so as to avoid the problem of microbial growth in the cooling tower.

Further, sulfuric acid and water quality stabilizer are added to the effluent of the clear water tank to improve the concentration ratio of circulating water and meet the requirements of water saving and emission reduction.

Further, the backwash water of the gravity valveless filter is recycled to the oil skimming pre-sedimentation adjustment tank, and the sludge of the oil skimming pre-sedimentation adjustment tank, the sludge of the high-efficiency flocculation tank and the sludge of the inclined tube clarifier are passed through the coal slime. The concentration tank and the filter press are concentrated and dehydrated. The supernatant of the slime concentration tank is recycled to the oil skimming pre-sedimentation adjustment tank for further treatment. The mud cake discharged from the filter press is transported together with the raw coal through the coal conveying trestle to the separator. In the coal plant, in the process of mine water treatment, the waste water, mine water and coal slime discharged from the system are all utilized as resources.

Description of drawings

FIG. 1 is a schematic structural diagram of the present invention.

Among them, 1 is the oil skimming pre-sedimentation adjustment tank, 2 is the raw water lift pump, 3 is the coagulant dosing device, 4 is the coagulation aid dosing device, 5 is the high-efficiency flocculation tank, 6 is the inclined tube clarifier, and 7 is the coal Mud concentration tank, 8 is mud pump, 9 is filter press, 10 is gravity valveless filter, 11 is bactericide dosing device, 12 is clear water tank, 13 is reuse water pump, 14 is water stabilizer dosing The device, 15 is a sulfuric acid dosing device, and 16 is a cooling tower.

Detailed ways

Below in conjunction with accompanying drawing, the present invention is described in further detail:

Referring to Fig. 1, the high suspended solids mine water of the present invention is used as a treatment system for circulating water replenishment in a power plant, including a mine water inlet pipe, an oil skimming pre-sedimentation adjustment tank 1, a coagulant dosing device 3, and a coagulant aid dosing device 4. , high-efficiency flocculation tank 5, inclined tube clarifier 6, gravity valveless filter tank 10, bactericide dosing device 11, clear water tank 12 and cooling tower 16; The inlet of the high-efficiency flocculation tank 5 is connected, the outlet of the coagulant dosing device 3 and the outlet of the coagulant-aid dosing device 4 are connected with the dosing port of the high-efficiency flocculation tank 5, and the outlet of the high-efficiency flocculation tank 5 is connected with the inclined tube clarifier. The inlet of 6 is connected, the supernatant outlet of the inclined tube clarifier 6 is connected with the inlet of the gravity valveless filter tank 10, the outlet of the gravity valveless filter tank 10 and the outlet of the bactericide dosing device 11 are connected with the clean water tank 12. The inlets are communicated with each other, and the outlet of the clear water tank 12 is communicated with the water inlet of the cooling tower 16 .

The sludge discharge port of the oil skimming pre-sedimentation adjustment tank 1, the sludge discharge port of the high-efficiency flocculation tank 5 and the sludge discharge port of the inclined tube clarifier 6 are all connected with the inlet of the coal slime concentration pool 7, and the supernatant of the coal slime concentration pool 7 is connected. The liquid outlet is communicated with the water inlet of the skimming pre-sedimentation adjustment tank 1 .

The coal slime outlet of the slime concentration tank 7 is communicated with the inlet of the filter press 9 through the sludge discharge pump 8; the clean water pool 12 and the cooling tower 16 are communicated with the recycling water pump 13; It is communicated with the interface of the dosing device of the water-replenishing mother pipe of the cooling tower 16 , and the outlet of the sulfuric acid dosing device 15 is communicated with the dosing port of the sulfuric acid in the tower pool in the cooling tower 16 .

The processing method of the high suspended solids mine water of the present invention as the circulating water replenishment water of the power plant comprises the following steps:

The mine water output by the mine water supply pipe is sent to the high-efficiency flocculation tank 5 through the raw water lift pump 2 after removing the large suspended impurities and floating oil through the oil skimming pre-sedimentation adjustment tank 1, and is added through the coagulant dosing device 3 and the coagulant aid. The device 4 adds a coagulant and a coagulant aid to the high-efficiency flocculation tank 5;

The oil skimming pre-settling adjustment tank 1 is mainly used to remove large suspended impurities and oil slicks in the mine water. The oil skimming pre-sediment adjustment tank 1 adopts a rectangular semi-underground reinforced concrete structure and is equipped with a truss-type mud scraper, which will settle at the bottom of the tank. The sludge is scraped and collected to the sludge collecting tank, and then the sludge is transported to the sludge concentration tank 7 through the sludge discharge pipe. Discharge the dirty oil into the dirty oil tank for recycling;

The coagulant adopts polyaluminum chloride (PAC), the alkalinity degree of PAC is between 60% and 80%, the content of alumina (AI ₂ O ₃ ) is ≥ 30%, and the effective dosage is ≥ 10mg/L; The coagulant is made of polyacrylamide (PAM), and the dosage is ≤1mg/L. The specific dosage of PAC and PAM needs to be determined by the beaker test according to the mine water quality;

The tank body of the high-efficiency flocculation tank 5 is divided into a first reaction zone and a second reaction zone by a partition plate, and one mixer is installed in the first reaction zone and the second reaction zone, and the reaction time is 10-15 minutes. Wherein, adding PAC in the first reaction zone causes the suspended matter in the mine water to undergo a coagulation reaction, and the second reaction zone is used for receiving PAM agent and the overflow water of the first reaction zone and stirring for flocculation;

The effluent from the high-efficiency flocculation tank 5 flows into the inclined tube clarifier 6 by itself, and the up-flow out-of-phase flow is adopted. The length of the inclined tube is 1-1.2 m, the vertical clear distance is 0.8-1 m, the inclination angle is 60°, and the residence time is 40- 60min, adopt gravity to discharge sludge, pass through high-efficiency flocculation tank 5 and inclined tube clarifier 6 to reduce the suspended solids, chromaticity and macromolecular organic matter of mine water;

The effluent of the inclined tube clarifier 6 and the gravity valveless filter tank 10 are connected by gravity flow, and the gravity valveless filter tank 10 uses the gravity of the water body to complete the filtration and backwashing process, and the power consumption is low. The gravity valveless filter tank 10 adopts a low-resistance filter plate water distribution system. The gravity valveless filter tank 10 is provided with anthracite and quartz sand double-layer filter materials. The particle size of the double-layer filter material is 0.5-1.0mm, and the thickness is 300mm. The lower side of the quartz sand double-layer filter material is provided with a supporting layer, and the supporting layer is coarse sand with a particle size of 1-2mm and a thickness of 100mm;

The outlet of the gravity valveless filter tank ₁₀ and the outlet of the bactericide dosing device ₁₁ are all connected with the inlet of the clean water tank 12. Residual chlorine is controlled at 0.3-0.5mg/L;

The clean water tank 12 and the cooling tower 16 are connected through the reuse water pump 13. In order to meet the high concentration ratio operation requirements of the circulating water, the outlet of the water quality stabilizer dosing device 14 is connected with the dosing port of the jelly outlet pipe of the reuse water pump 13. , the outlet of the sulfuric acid dosing device 15 is connected with the dosing port of the cooling tower 16 tower pool, and the concentration ratio of the circulating water is controlled to be ≥6 times, the alkalinity is ≤7mmol/L, and the pH=8.5～8.7.

The bottom sludge pipe outlet of the oil skimming pre-sedimentation adjustment tank 1, the bottom sludge pipe outlet of the high-efficiency flocculation tank 5 and the bottom sludge pipe outlet of the inclined pipe clarifier 6 are all connected with the inlet of the slime concentration tank 7, and the The concentrated sludge enters the filter press 9 under the action of the sludge discharge pump 8 for sludge dewatering, and the mud cake formed after the filter press is transported to the coal preparation plant together with the raw coal through the coal transport trestle.

The supernatant liquid outlet of the coal slime concentration tank 7 and the backwash water outlet of the gravity valveless filter tank 10 are both communicated with the inlet of the oil skimming pre-sedimentation adjustment tank 1 .

The above is only an example of the implementation steps of the present invention. It should be pointed out that for those skilled in the art, without departing from the technical principle of the present invention, several improvements and modifications can also be made. These improvements and Variations should also be considered within the scope of protection of the present invention.

Claims (10)

1. A treatment system for taking high suspended substance mine water as circulating water replenishing water of a power plant is characterized by comprising a mine water incoming pipe, an oil skimming pre-settling regulation pool (1), a coagulant adding device (3), a coagulant adding device (4), a high-efficiency flocculation pool (5), an inclined tube clarification pool (6), a gravity valveless filter pool (10), a bactericide adding device (11), a clean water pool (12) and a cooling tower (16);

the water outlet of a mine water inlet pipe is communicated with the inlet of a high-efficiency flocculation tank (5) through an oil skimming pre-settling regulation tank (1), the outlet of a coagulant adding device (3) and the outlet of a coagulant adding device (4) are communicated with a medicine adding port of the high-efficiency flocculation tank (5), the outlet of the high-efficiency flocculation tank (5) is communicated with the inlet of an inclined-tube clarification tank (6), the supernatant outlet of the inclined-tube clarification tank (6) is communicated with the inlet of a gravity valveless filter (10), the outlet of the gravity valveless filter (10) and the outlet of a bactericide adding device (11) are communicated with the inlet of a clear water tank (12), and the outlet of the clear water tank (12) is communicated with the water inlet of a cooling tower (16).

2. The system for treating the high suspended substance mine water as the replenishing water of the circulating water of the power plant according to claim 1, wherein the oil skimming pre-settling regulation pool (1) is communicated with the high-efficiency flocculation pool (5) through a raw water lift pump (2), and the oil skimming pre-settling regulation pool (1) is provided with a truss car type mud scraper, an oil scraper and an oil collecting pipe.

3. The system for treating the high suspended substance mine water as the replenishing water of the circulating water of the power plant according to claim 1, wherein the tank body of the high-efficiency flocculation tank (5) is divided into a first reaction area and a second reaction area by a partition plate, wherein the first reaction area is communicated with the coagulant adding device (3), and the second reaction area is communicated with the coagulant adding device (4).

4. The system for treating the high suspended substance mine water as the replenishing water of the circulating water of the power plant according to claim 1, characterized in that an up-flow type heterogeneous flow is adopted in the inclined tube clarification tank (6), the length of an inclined tube in the inclined tube clarification tank (6) is 1-1.2 m, the vertical clear distance is 0.8-1 m, the inclination angle is 60 degrees, the retention time of the water is 40-60 min, and the gravity sludge discharge is adopted in the inclined tube clarification tank (6).

5. The system for treating the high suspended substance mine water as the circulating water replenishing water of the power plant according to claim 1, characterized by further comprising a coal mud concentration tank (7), wherein a mud discharge port of the oil skimming pre-settling regulation tank (1), a mud discharge port of the high-efficiency flocculation tank (5) and a mud discharge port of the inclined tube clarification tank (6) are communicated with an inlet of the coal mud concentration tank (7), and a supernatant outlet of the coal mud concentration tank (7) is communicated with a water inlet of the oil skimming pre-settling regulation tank (1).

6. The system for treating the high suspended substance mine water as the replenishing water of the circulating water of the power plant according to claim 5, characterized in that a coal slurry outlet of the coal slurry concentration tank (7) is communicated with an inlet of a filter press (9) through a sludge discharge pump (8).

7. The system for treating the high suspended substance mine water as the replenishing water of the circulating water of the power plant according to claim 1, wherein a backwash water outlet of the gravity valveless filter (10) is communicated with a water inlet of the oil skimming pre-settling regulating tank (1), and anthracite and quartz sand double-layer filter materials and a bearing layer are sequentially arranged in the gravity valveless filter (10) from top to bottom.

8. The system for treating the high suspended solid mine water as the replenishing water of the circulating water of the power plant according to claim 1, wherein the clean water tank (12) is communicated with the cooling tower (16) through a reuse water pump (13).

9. The system for treating the high suspended solid mine water as the circulating water replenishing water of the power plant according to claim 1, further comprising a water quality stabilizer dosing device (14) and a sulfuric acid dosing device (15), wherein an outlet of the water quality stabilizer dosing device (14) is communicated with a dosing device interface of a main water replenishing pipe of the cooling tower (16), and an outlet of the sulfuric acid dosing device (15) is communicated with a sulfuric acid dosing port of a tower pond in the cooling tower (16).

10. A treatment method for taking high-suspended substance mine water as circulating water replenishing water of a power plant is characterized by comprising the following steps:

the method comprises the steps of adopting a high-efficiency flocculation tank (5), adding a coagulant and a coagulant aid to destabilize suspended impurities which are difficult to settle and have small particle sizes in mine water to form large flocs, performing solid-liquid separation through an inclined tube clarification tank (6), and further removing suspended matters, chromaticity and macromolecular organic matters in water from the effluent of the inclined tube clarification tank (6) through a gravity valveless filter (10) to ensure that the suspended matters in the effluent are less than or equal to 10 mg/L.

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