CN211004938U

CN211004938U - Coal-fired power plant wastewater zero-discharge process system based on semi-dry desulfurization technology

Info

Publication number: CN211004938U
Application number: CN201921035791.6U
Authority: CN
Inventors: 王仁雷; 张山山; 于卫卫; 骆奇君
Original assignee: Huadian Electric Power Research Institute Co Ltd
Current assignee: Huadian Electric Power Research Institute Co Ltd
Priority date: 2019-07-04
Filing date: 2019-07-04
Publication date: 2020-07-14
Anticipated expiration: 2029-07-04

Abstract

The utility model discloses a coal fired power plant waste water zero release process systems based on semidry desulfurization technique, the system include waste water equalizing basin, acidification device, add alkali device, charge system, folded plate flocculation basin, pipe chute sedimentation tank, clean water basin, high efficiency fiber filter, filter tank, electric adsorption device, product water tank, cooling tower, thick water tank, desulfurization process water tank, lime storehouse, flue gas circulating fluidized bed desulfurization absorption tower, sack cleaner, desulfurization ash storehouse and chimney. The utility model discloses can carry out concentrated decrement to coal power plant's salt waste water effectively, the system is produced water and is retrieved to the cooling tower as the make-up water, and dense water is as flue gas circulating fluidized bed semidry desulfurization system's humidification water to realize the waste water zero release, have characteristics such as the treatment effect is stable, the working costs is low, process systems is simple.

Description

Coal-fired power plant wastewater zero-discharge process system based on semi-dry desulfurization technology

Technical Field

The utility model belongs to the technical field of coal fired power plant wastewater treatment and retrieval and utilization technique and specifically relates to a coal fired power plant wastewater zero release process systems based on semidry process desulfurization technique is related to.

Background

The salt-containing wastewater which is difficult to treat in the coal-fired power plant mainly comprises circulating water sewage, ion exchange system regeneration wastewater, reverse osmosis concentrated water, desulfurization wastewater and the like, wherein the circulating water sewage has the characteristics of large water discharge capacity, higher salt content, higher hardness and alkalinity and the like, and the existing domestic engineering implemented circulating water sewage treatment process mainly comprises the following steps: coagulation clarification + filtration, pretreatment + reverse osmosis, pretreatment + ultrafiltration + reverse osmosis and the like, as in the Chinese patent with the application number of 201710942060.9, but the system has the defects of poor running stability, prominent membrane pollution phenomenon, low recovery rate of less than 70 percent and difficult recycling caused by poor quality of concentrated water.

At present, many coal-fired power plants adopt a flue gas circulating fluidized bed semidry method desulfurization technology in China, and compared with other flue gas desulfurization technologies, the technology has the remarkable advantages of less investment, low operating cost, small occupied area, less water consumption, no desulfurization wastewater discharge and the like. The technology needs to use a certain amount of process water as humidifying water to reduce the temperature of flue gas in the desulfurization absorption tower and improve the desulfurization efficiency. By utilizing the process characteristics, the concentrated water which is generated by the coal-fired power plant salt-containing wastewater treatment system and is difficult to recycle can be effectively treated, and zero discharge of wastewater is realized.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome the above-mentioned not enough that exists among the prior art, and provide a coal fired power plant waste water zero release process systems based on semidry desulfurization technique, can handle and the retrieval and utilization waste water effectively to realize the waste water zero release.

The utility model provides a technical scheme that above-mentioned problem adopted is: a coal-fired power plant wastewater zero-discharge process system based on a semi-dry desulfurization technology is characterized by comprising a wastewater adjusting tank, an acid adding device, an alkali adding device, a medicine adding system, a folded plate flocculation tank, an inclined tube sedimentation tank, a clean water tank, a high-efficiency fiber filter, a filter water tank, an electric adsorption device, a water production tank, a cooling tower, a concentrated water tank, a desulfurization process water tank, a lime slaking bin, a flue gas circulating fluidized bed desulfurization absorption tower, a bag-type dust remover, a desulfurization ash bin and a chimney; the outlet of the acid adding device and the outlet of the alkali adding device are communicated with the water inlet of the wastewater adjusting tank, the air outlet of the Roots blower is communicated with the air inlet at the bottom of the wastewater adjusting tank, the water outlet of the wastewater adjusting tank is communicated with the water inlet of the folded plate flocculation tank, the outlet of the chemical adding system is communicated with the chemical inlet of the folded plate flocculation tank, the water outlet of the folded plate flocculation tank is communicated with the clean water tank through an inclined tube sedimentation tank, the water outlet of the clean water tank is communicated with a filter water tank through a high-efficiency fiber filter, the water outlet of the filter water tank is communicated with the water inlet of the electro-adsorption device, the produced water outlet and the concentrated water outlet of the electro-adsorption device are respectively communicated with the water inlet of the produced water tank and the water inlet of the concentrated water tank, the water outlet of the produced water tank is communicated with the water replenishing port of, the water outlet of the desulfurization process water tank is communicated with a humidifying water inlet of the flue gas circulating fluidized bed desulfurization absorption tower, an absorbent outlet at the bottom of the lime hydrate cabin is communicated with an absorbent inlet of the flue gas circulating fluidized bed desulfurization absorption tower, a flue gas outlet of the flue gas circulating fluidized bed desulfurization absorption tower is communicated with a flue gas inlet of a bag-type dust remover, a dust hopper at the bottom of the bag-type dust remover is respectively communicated with a recycling material inlet of the flue gas circulating fluidized bed desulfurization absorption tower and a desulfurization dust bin, and a flue gas outlet of the bag-type dust remover is communicated with a chimney.

Further, the dosing system comprises a coagulant dosing device and a coagulant aid dosing device, and an outlet of the coagulant dosing device and an outlet of the coagulant aid dosing device are both communicated with a medicament inlet of the folded plate flocculation tank.

Further, still include sludge concentration tank and hydroextractor, sludge concentration tank's entry is linked together with the row mud mouth of pipe chute sedimentation tank bottom, sludge concentration tank's bottom mud outlet is linked together with the entry of hydroextractor, sludge concentration tank's supernatant export and the delivery port of hydroextractor all are linked together with the water inlet of waste water equalizing basin.

Furthermore, a self-service water outlet of the high-efficiency fiber filter is communicated with a water inlet of the wastewater adjusting tank.

Further, a water outlet of the wastewater adjusting tank is communicated with a water inlet of the folded plate flocculation tank through a wastewater pump; a sludge outlet at the bottom of the sludge concentration tank is communicated with an inlet of the dehydrator through a sludge delivery pump; the water outlet of the clean water tank is communicated with the water inlet of the high-efficiency fiber filter through a clean water pump; the water outlet of the filtering water tank is communicated with the water inlet of the electric adsorption device through a water feeding pump; the delivery port of product water tank and the moisturizing mouth of cooling tower are linked together through producing the water pump, the delivery port of dense water tank and the moisturizing mouth of desulfurization process water tank pass through dense water pump and are linked together, the delivery port of desulfurization process water tank and the humidification water entry of flue gas circulating fluidized bed desulfurization absorption tower pass through high pressure water pump and communicate mutually, the absorbent outlet of slaking lime storehouse bottom and the absorbent entry of flue gas circulating fluidized bed desulfurization absorption tower are linked together through the feeding chute, the ash bucket of sack cleaner bottom and the recirculated material entry of flue gas circulating fluidized bed desulfurization absorption tower are linked together through the circulating air chute, the ash bucket of sack cleaner bottom and desulfurization ash storehouse are linked together through the storehouse pump, the exhanst gas outlet and the chimney of sack cleaner are linked together through the desulfurization draught fan.

Compared with the prior art, the utility model, have following advantage and effect: in the process of treating the wastewater of the coal-fired power plant, the pH adjustment is carried out in the wastewater adjusting tank in sequence, the coagulant and the coagulant aid are added into the folded plate flocculation tank for coagulation reaction, the coagulation reaction is carried out in the inclined tube sedimentation tank, the coagulation reaction is carried out in the high-efficiency fiber filter, the effluent water reaches the suspended matters less than 3-5 mg/l, the turbidity is 2-3 NTU, and the water inlet requirement of the electro-adsorption desalting device is met. And then desalting treatment is carried out on the electric adsorption device, finally, produced water is recycled to a cooling tower as make-up water, concentrated water is used as process humidifying water to enter a flue gas circulating fluidized bed desulfurization absorption tower, atomized humidifying water is contacted with high-temperature flue gas, and the humidifying water is evaporated by utilizing the temperature of the flue gas, so that zero discharge of waste water is realized. Meanwhile, the filter adopts a high-efficiency fiber filter material, a small-resistance water distribution system, an air-water backwashing and constant water level filtering mode, and has the characteristics of good sewage interception performance and good backwashing effect. The desalting system adopts an electric adsorption device, has low requirement on water inlet, does not need to add a scale inhibitor and a reducing agent, and has low operation energy consumption. The high-pressure atomization backflow type nozzle is arranged at the humidifying water inlet of the flue gas circulating fluidized bed desulfurization absorption tower, has the characteristics of good spraying effect, adjustable flow, simple structure and the like, and can meet the atomization requirement through the high-pressure water pump.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

In the figure: the system comprises a wastewater adjusting tank 1, an acid adding device 2, an alkali adding device 3, a Roots blower 4, a wastewater pump 5, a coagulant adding device 6, a coagulant aid adding device 7, a folded plate flocculation tank 8, an inclined tube sedimentation tank 9, a sludge concentration tank 10, a sludge delivery pump 11, a dehydrator 12, a clean water tank 13, a clean water pump 14, a high-efficiency fiber filter 15, a filter water tank 16, a water feeding pump 17, an electric adsorption device 18, a water production tank 19, a water production pump 20, a cooling tower 21, a concentrated water tank 22, a concentrated water pump 23, a desulfurization process water tank 24, a high-pressure water pump 25, a slaked lime bin 26, a feeding chute 27, a flue gas circulating fluidized bed desulfurization absorption tower 28, a cloth bag dust remover 29, a circulating air chute 30, a bin pump 31, a desulfurization ash bin 32, a desulfurization induced draft fan 33 and a.

Detailed Description

The present invention will be described in further detail by way of examples with reference to the accompanying drawings, which are illustrative of the present invention and are not intended to limit the present invention.

Referring to fig. 1, the coal-fired power plant wastewater zero discharge process system based on the semi-dry desulfurization technology in the embodiment is characterized by comprising a wastewater adjusting tank 1, an acid adding device 2, an alkali adding device 3, a chemical adding system, a folded plate flocculation tank 8, an inclined tube sedimentation tank 9, a clean water tank 13, a high-efficiency fiber filter 15, a filter water tank 16, an electric adsorption device 18, a water production tank 19, a cooling tower 21, a concentrated water tank 22, a desulfurization process water tank 24, a slaked lime bin 26, a flue gas circulating fluidized bed desulfurization absorption tower 28, a bag-type dust collector 29, a desulfurization ash bin 32 and a chimney 34.

The outlet of the acid adding device 2 and the outlet of the alkali adding device 3 are communicated with the water inlet of the wastewater adjusting tank 1, the air outlet of the Roots blower 4 is communicated with the air inlet at the bottom of the wastewater adjusting tank 1, the water outlet of the wastewater adjusting tank 1 is communicated with the water inlet of the folded plate flocculation tank 8, the outlet of the dosing system is communicated with the medicament inlet of the folded plate flocculation tank 8, the water outlet of the folded plate flocculation tank 8 is communicated with the clean water tank 13 through the inclined tube sedimentation tank 9, the water outlet of the clean water tank 13 is communicated with the filter water tank 16 through the high-efficiency fiber filter 15, the water outlet of the filter water tank 16 is communicated with the water inlet of the electric adsorption device 18, the produced water outlet and the concentrated water outlet of the electric adsorption device 18 are respectively communicated with the water inlet of the produced water tank 19 and the water inlet of the concentrated water tank 22, the water outlet of the produced water tank 19 is communicated with the water replenishing port, the water outlet of the desulfurization process water tank 24 is communicated with the humidifying water inlet of the flue gas circulating fluidized bed desulfurization absorption tower 28, the absorbent outlet at the bottom of the slaked lime bin 26 is communicated with the absorbent inlet of the flue gas circulating fluidized bed desulfurization absorption tower 28, the flue gas outlet of the flue gas circulating fluidized bed desulfurization absorption tower 28 is communicated with the flue gas inlet of the bag-type dust remover 29, the ash bucket at the bottom of the bag-type dust remover 29 is respectively communicated with the recycling material inlet of the flue gas circulating fluidized bed desulfurization absorption tower 28 and the desulfurization ash bin 32, and the flue gas outlet of the bag-type dust remover 29 is communicated with the chimney 34.

In this embodiment, the dosing system comprises a coagulant dosing device 6 and a coagulant aid dosing device 7, and the outlet of the coagulant dosing device 6 and the outlet of the coagulant aid dosing device 7 are both communicated with the medicament inlet of the folded plate flocculation tank 8.

In addition, the system also comprises a sludge concentration tank 10 and a dehydrator 12, wherein an inlet of the sludge concentration tank 10 is communicated with a sludge discharge port at the bottom of the inclined tube sedimentation tank 9, a sludge outlet at the bottom of the sludge concentration tank 10 is communicated with an inlet of the dehydrator 12, and a supernatant outlet of the sludge concentration tank 10 and a water outlet of the dehydrator 12 are both communicated with a water inlet of the wastewater adjusting tank 1. The self-used water outlet of the high-efficiency fiber filter 15 is communicated with the water inlet of the wastewater adjusting tank 1. The water outlet of the wastewater adjusting tank 1 is communicated with the water inlet of the folded plate flocculation tank 8 through a wastewater pump 5; the bottom sludge outlet of the sludge concentration tank 10 is communicated with the inlet of the dehydrator 12 through a sludge delivery pump 11; the water outlet of the clean water tank 13 is communicated with the water inlet of the high-efficiency fiber filter 15 through a clean water pump 14; the water outlet of the filter water tank 16 is communicated with the water inlet of the electric adsorption device 18 through a water feeding pump 17; the water outlet of the water production tank 19 is communicated with the water replenishing port of the cooling tower 21 through a water production pump 20, the water outlet of the concentrated water tank 22 is communicated with the water replenishing port of the desulfurization process water tank 24 through a concentrated water pump 23, the water outlet of the desulfurization process water tank 24 is communicated with the humidifying water inlet of the flue gas circulating fluidized bed desulfurization absorption tower 28 through a high-pressure water pump 25, the absorbent outlet at the bottom of the slaked lime bin 26 is communicated with the absorbent inlet of the flue gas circulating fluidized bed desulfurization absorption tower 28 through a feeding chute 27, the ash hopper at the bottom of the bag-type dust remover 29 is communicated with the recycling material inlet of the flue gas circulating fluidized bed desulfurization absorption tower 28 through a circulating air chute 30, the ash hopper at the bottom of the bag-type dust remover 29 is communicated with the desulfurization ash bin 32 through a bin pump 31, and the flue gas outlet.

The working process is as follows: the method comprises the steps of adjusting the pH value of the coal-fired power plant wastewater to 6-9 in a wastewater adjusting tank 1 under the air stirring action of an acid adding device 2 or an alkali adding device 3 and a Roots blower 4, feeding the wastewater into a folded plate flocculation tank 8 through a wastewater pump 5, adding a coagulant and a coagulant aid into the folded plate flocculation tank 8 through a coagulant adding device 6 and a coagulant aid adding device 7 for coagulation reaction, then precipitating in an inclined tube sedimentation tank 9, allowing sludge generated by the inclined tube sedimentation tank 9 to enter a sludge concentration tank 10 for sedimentation and concentration, allowing sludge discharged from the sludge concentration tank 10 to enter a dehydrator 12 through a sludge delivery pump 11 for dehydration, returning supernatant of the sludge concentration tank 10 and water removed from the dehydrator 12 to the wastewater adjusting tank 1, allowing water discharged from the inclined tube sedimentation tank 9 to enter a clear water tank 13, allowing the water to enter a high-efficiency fiber filter 15 through a clear water pump 14 for filtration treatment, and allowing self-used water of the high-efficiency fiber, the effluent of the high-efficiency fiber filter 15 enters a filter water tank 16 and enters an electric adsorption device 18 through a feed pump 17 for desalination treatment, the produced water of the electric adsorption device 18 enters a water production tank 19, concentrated water enters a concentrated water tank 22, the effluent of the water production tank 19 is recycled to a cooling tower 21 as make-up water through a water production pump 20, the effluent of the concentrated water tank 22 is recycled to a desulfurization process water tank 24 through a concentrated water pump 23 as process water, the effluent of the desulfurization process water tank 24 enters a water gap of a flue gas circulating fluidized bed desulfurization absorption tower 28 through a high-pressure water pump 25 for humidification and spray evaporation, an absorbent at the bottom of a slaked lime bin 26 is sent to an absorbent inlet of the flue gas circulating fluidized bed desulfurization absorption tower 28 through a feed chute 27 for desulfurization reaction, evaporation and drying products are collected at a bag-type dust collector 29 along with the outlet flue gas of the flue gas circulating fluidized bed desulfurization absorption tower 28, and most of ash at the bottom of the bag-type dust collector 29 returns to a At the inlet, a small part of ash is conveyed to a desulfurization ash storage 32 through a bin pump 31, and the flue gas at the outlet of the bag-type dust collector 29 enters a chimney 34 through a desulfurization induced draft fan 33 to be discharged.

Wherein, the electro-adsorption device 18 adopts two working processes of operation and regeneration, and the electro-adsorption module is pickled regularly, the recovery rate is 70-80%, and the desalination rate is 70-75%; a humidifying water inlet of the flue gas circulating fluidized bed desulfurization absorption tower 28 is provided with a high-pressure atomization reflux type nozzle; the inlet of the high-pressure water pump 25 is provided with a filtering device, and the high-pressure process water is not lower than 3.5MPa, so that the atomization requirement can be met through the high-pressure water pump 25.

Although the present invention has been described with reference to the above embodiments, it should not be construed as being limited to the scope of the present invention, and any modifications made by those skilled in the art without departing from the spirit and scope of the present invention should be construed as being included in the following claims.

Claims

1. A coal-fired power plant wastewater zero-discharge process system based on a semi-dry desulfurization technology is characterized by comprising a wastewater adjusting tank (1), an acid adding device (2), an alkali adding device (3), a medicine adding system, a folded plate flocculation tank (8), an inclined tube sedimentation tank (9), a clean water tank (13), a high-efficiency fiber filter (15), a filter water tank (16), an electric adsorption device (18), a water production tank (19), a cooling tower (21), a concentrated water tank (22), a desulfurization process water tank (24), a slaked lime bin (26), a flue gas circulating fluidized bed desulfurization absorption tower (28), a bag-type dust collector (29), a desulfurization ash bin (32) and a chimney (34); the outlet of the acid adding device (2) and the outlet of the alkali adding device (3) are communicated with the water inlet of the wastewater adjusting tank (1), the air outlet of the Roots blower (4) is communicated with the air inlet at the bottom of the wastewater adjusting tank (1), the water outlet of the wastewater adjusting tank (1) is communicated with the water inlet of the folded plate flocculation tank (8), the outlet of the chemical adding system is communicated with the chemical inlet of the folded plate flocculation tank (8), the water outlet of the folded plate flocculation tank (8) is communicated with the clear water tank (13) through an inclined tube sedimentation tank (9), the water outlet of the clear water tank (13) is communicated with the filter water tank (16) through a high-efficiency fiber filter (15), the water outlet of the filter water tank (16) is communicated with the water inlet of the electric adsorption device (18), and the produced water outlet and the concentrated water outlet of the electric adsorption device (18) are respectively communicated with the water inlet of the produced water tank (, The water inlet of the concentrated water tank (22) is communicated, the water outlet of the water production tank (19) is communicated with the water replenishing port of the cooling tower (21), the water outlet of the concentrated water tank (22) is communicated with the water replenishing port of the desulfurization process water tank (24), the water outlet of the desulfurization process water tank (24) is communicated with the humidifying water inlet of the flue gas circulating fluidized bed desulfurization absorption tower (28), an absorbent outlet at the bottom of the slaked lime bin (26) is communicated with an absorbent inlet of the flue gas circulating fluidized bed desulfurization absorption tower (28), the flue gas outlet of the flue gas circulating fluidized bed desulfurization absorption tower (28) is communicated with the flue gas inlet of a bag-type dust remover (29), an ash bucket at the bottom of the bag-type dust collector (29) is respectively communicated with a recycling material inlet of the flue gas circulating fluidized bed desulfurization absorption tower (28) and a desulfurization ash bin (32), and a smoke outlet of the bag-type dust collector (29) is communicated with a chimney (34).

2. The coal-fired power plant wastewater zero emission process system based on the semi-dry desulfurization technology as claimed in claim 1, wherein the dosing system comprises a coagulant dosing device (6) and a coagulant aid dosing device (7), and an outlet of the coagulant dosing device (6) and an outlet of the coagulant aid dosing device (7) are both communicated with a medicament inlet of the folded plate flocculation tank (8).

3. The coal-fired power plant wastewater zero emission process system based on the semidry desulfurization technology of claim 1, characterized by further comprising a sludge concentration tank (10) and a dehydrator (12), wherein an inlet of the sludge concentration tank (10) is communicated with a sludge discharge port at the bottom of the inclined tube sedimentation tank (9), a sludge discharge port at the bottom of the sludge concentration tank (10) is communicated with an inlet of the dehydrator (12), and a supernatant outlet of the sludge concentration tank (10) and a water outlet of the dehydrator (12) are both communicated with a water inlet of the wastewater adjusting tank (1).

4. The coal-fired power plant wastewater zero emission process system based on the semidry desulfurization technology as set forth in claim 1, wherein the self-water outlet of the high-efficiency fiber filter (15) is communicated with the water inlet of the wastewater adjusting tank (1).

5. The coal-fired power plant wastewater zero emission process system based on the semidry desulfurization technology as claimed in claim 3, wherein the water outlet of the wastewater adjusting tank (1) is communicated with the water inlet of the folded plate flocculation tank (8) through a wastewater pump (5); a sludge outlet at the bottom of the sludge concentration tank (10) is communicated with an inlet of a dehydrator (12) through a sludge delivery pump (11); the water outlet of the clean water tank (13) is communicated with the water inlet of the high-efficiency fiber filter (15) through a clean water pump (14); the water outlet of the filtering water tank (16) is communicated with the water inlet of the electric adsorption device (18) through a water feeding pump (17); the water outlet of the water production tank (19) is communicated with the water replenishing port of the cooling tower (21) through a water production pump (20), the water outlet of the concentrated water tank (22) is communicated with the water replenishing port of the desulfurization process water tank (24) through a concentrated water pump (23), the water outlet of the desulfurization process water tank (24) is communicated with the humidifying water inlet of the flue gas circulating fluidized bed desulfurization absorption tower (28) through a high-pressure water pump (25), the absorbent outlet at the bottom of the lime slaking bin (26) is communicated with the absorbent inlet of the flue gas circulating fluidized bed desulfurization absorption tower (28) through a feeding chute (27), the ash hopper at the bottom of the cloth bag dust remover (29) is communicated with the recycling material inlet of the flue gas circulating fluidized bed desulfurization absorption tower (28) through a circulating air chute (30), and the ash hopper at the bottom of the cloth bag dust remover (29) is communicated with a desulfurization ash bin (32) through a bin pump (31), and a flue gas outlet of the bag-type dust collector (29) is communicated with a chimney (34) through a desulfurization induced draft fan (33).