Desulfurization slurry treatment system

Abstract

The utility model discloses a desulfurization slurry treatment system which comprises a desulfurization slurry input pipe, a clarification tank, a buffer tank, a lifting pump, a diaphragm pump and a plate-and-frame filter press, the desulfurization slurry input pipe is divided into two paths which are respectively connected with a liquid inlet of the clarification tank and wet quenching coke, a supernatant outlet of the clarification tank is connected with a first liquid inlet of the buffer tank through a pipeline, and a second liquid inlet of the buffer tank is connected with a second liquid outlet of the plate-and-frame filter press; a liquid outlet of the buffer pool is respectively connected to a first buffer solution shunting pipe, a second buffer solution shunting pipe and a third buffer solution shunting pipe through a lifting pump, the first buffer solution shunting pipe is connected with the desulfurizing tower, the second buffer solution shunting pipe is connected with the wet quenching coke, and the third buffer solution shunting pipe is connected with the dosing system; a sludge outlet of the clarification tank is connected with a plate-and-frame filter press through a diaphragm pump, and a filtrate outlet of the plate-and-frame filter press flows back to the buffer tank. According to the utility model, the dosing treatment cost is reduced, the faults of the dosing system are also greatly reduced, the maintenance cost of the dosing system is reduced, and the service life of equipment is prolonged.

Description

Technical Field

[0001] The utility model relates to a slurry treatment system, in particular to a desulfurized slurry treatment system, belonging to the field of wastewater treatment. Background Technique

[0002] At present, for the treatment of desulfurized slurry in thermal power plants, the process of filtration → dosing → clarification → pressing filter cake is usually adopted. In this process, all the desulfurized slurry generated in the thermal power plant needs to be treated with chemicals, resulting in high chemical dosing costs. Moreover, the filtrate generated in the process of pressing the filter cake needs to be recycled to the chemical dosing tank for secondary treatment, further increasing the chemical dosing cost. In addition, the equipment failure rate is high, and the operation level of operators is required to be relatively high.

[0003] The desulfurized slurry treatment system often accompanies thermal power generation. After the boiler's regular blowdown, continuous blowdown, and internal leakage of the system and other water resources enter the regular blowdown expansion vessel, they are often treated by discharging them into the production wastewater system, resulting in waste of water resources.

[0004] Therefore, there is an urgent need for a desulfurized slurry treatment system that can not only recycle the boiler's external drainage resources, but also reduce the chemical dosing cost and the operation difficulty. Content of the Utility Model

[0005] The technical problem to be solved by the utility model is to provide a desulfurized slurry treatment system to reduce the chemical dosing cost of desulfurized slurry.

[0006] To solve the above technical problem, the technical solution adopted by the present invention is:

[0007] A desulfurized slurry treatment system includes a desulfurized slurry input pipe, a clarification tank, a buffer tank, a lift pump, a diaphragm pump, and a plate and frame filter press. The desulfurized slurry input pipe is connected to the liquid inlet of the clarification tank through a first desulfurized slurry shunt pipe, and the desulfurized slurry input pipe is connected to wet coke quenching through a second desulfurized slurry shunt pipe. The supernatant outlet of the clarification tank is connected to the first liquid inlet of the buffer tank through a pipeline. The liquid outlet of the buffer tank is connected to one end of the lift pump through a pipeline. The other end of the lift pump is connected to one end of a first buffer liquid shunt pipe, a second buffer liquid shunt pipe, and a third buffer liquid shunt pipe through pipelines. The other end of the first buffer liquid shunt pipe is connected to a desulfurization tower, the other end of the second buffer liquid shunt pipe is connected to wet coke quenching, and the other end of the third buffer liquid shunt pipe is connected to a chemical dosing system. The sludge outlet of the clarification tank is connected to one end of the diaphragm pump through a pipeline, the other end of the diaphragm pump is connected to the feed inlet of the plate and frame filter press through a pipeline, and the filtrate outlet of the plate and frame filter press is connected to the third liquid inlet of the buffer tank through a pipeline.

[0008] Further, a first shunt valve is provided on the first desulfurized slurry shunt pipe, and a second shunt valve is provided on the second desulfurized slurry shunt pipe.

[0009] Further, the supernatant outlet of the clarifier is an overflow outlet.

[0010] Further, the second liquid inlet of the buffer tank is connected to the condensate drain of the continuous blowdown flash tank.

[0011] Further, a first valve is provided on the pipeline between the liquid outlet of the buffer tank and the lift pump.

[0012] Further, a first buffer liquid diverter valve is provided on the first buffer liquid diverter pipe, a second buffer liquid diverter valve is provided on the second buffer liquid diverter pipe, and a third buffer liquid diverter valve is provided on the third buffer liquid diverter pipe.

[0013] Further, a second valve is provided on the pipeline between the sludge outlet of the clarifier and the diaphragm pump.

[0014] Further, a third valve is provided on the pipeline between the diaphragm pump and the feed inlet of the plate and frame filter press.

[0015] Compared with the prior art, the utility model has the following advantages and effects: The utility model applies the desulfurization slurry to the wet coke quenching process to complete the waste utilization of the desulfurization slurry. When there is no demand for the wet coke quenching process, the desulfurization slurry is preferentially returned to the desulfurization tower for treatment. Only when the desulfurization slurry has no utilization value, the dosing treatment is finally carried out, which greatly reduces the negative pressure of the dosing system operation, reduces the cost of the dosing treatment, and also significantly reduces the failures of the dosing system, reduces the maintenance cost of the dosing system, and extends the service life of the equipment; it recovers the condensate drain of the boiler continuous blowdown flash tank and reduces the concentration of the desulfurization slurry, forming a good internal circulation, further reducing the cost of the desulfurization slurry dosing treatment while achieving waste utilization; and because the buffer liquid in the buffer tank is finally dosed only when the concentration reaches a certain index, the concentration standard of the buffer liquid for dosing treatment is stable, the dosing amount is stable, and the requirements for the operators are low. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of a desulfurization slurry treatment system of the utility model.

[0017] Figure 2 is a partial schematic diagram of a desulfurization slurry treatment system of the utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] In order to elaborate in detail on the technical solutions adopted by the present utility model to achieve the predetermined technical objectives, the following will clearly and completely describe the technical solutions in the embodiments of the present utility model in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only partial embodiments of the present utility model, rather than all embodiments. Moreover, without creative labor, the technical means or technical features in the embodiments of the present utility model can be replaced. The following will illustrate the present utility model in detail with reference to the drawings and in conjunction with the embodiments.

[0019] As Figure 1 and Figure 2 shown, a desulfurization slurry treatment system of the present utility model includes a desulfurization slurry input pipe 1, a clarification tank 2, a buffer tank 3, a lift pump 4, a diaphragm pump 5, and a plate and frame filter press 6. The desulfurization slurry input pipe 1 is connected to the liquid inlet of the clarification tank 2 through a first desulfurization slurry shunt pipe 7. The desulfurization slurry input pipe 1 is connected to wet coke quenching through a second desulfurization slurry shunt pipe 8. The supernatant outlet of the clarification tank 2 is connected to the first liquid inlet of the buffer tank 3 through a pipeline. The liquid outlet of the buffer tank 3 is connected to one end of the lift pump 4 through a pipeline. The other end of the lift pump 4 is respectively connected to one end of a first buffer liquid shunt pipe 9, a second buffer liquid shunt pipe 10, and a third buffer liquid shunt pipe 11 through pipelines. The other end of the first buffer liquid shunt pipe 9 is connected to a desulfurization tower. The other end of the second buffer liquid shunt pipe 10 is connected to wet coke quenching. The other end of the third buffer liquid shunt pipe 11 is connected to a dosing system. The sludge outlet of the clarification tank 2 is connected to one end of the diaphragm pump 5 through a pipeline. The other end of the diaphragm pump 5 is connected to the feed inlet of the plate and frame filter press 6 through a pipeline. The filtrate outlet of the plate and frame filter press 6 is connected to the third liquid inlet of the buffer tank 3 through a pipeline.

[0020] Among them, a first shunt valve 12 is provided on the first desulfurization slurry shunt pipe 7, and a second shunt valve 13 is provided on the second desulfurization slurry shunt pipe 8. The on-off of the first desulfurization slurry shunt pipe 7 and the second desulfurization slurry shunt pipe 8 is controlled by the first shunt valve 12 and the second shunt valve 13. When the wet coke quenching process in the coking plant is working, the desulfurization slurry is sent into the wet coke quenching process section of the coking plant as the water source for the wet coke quenching process, which is the main means for daily low-cost treatment of desulfurization slurry. When there is no wet coke quenching in production, the desulfurization slurry is sent into the sedimentation tank 2 for static precipitation.

[0021] The supernatant outlet of the clarification tank 2 is an overflow port. The upper layer of the supernatant in the clarification tank 2 self-overflows into the buffer tank 3 through the overflow port. The second liquid inlet of the buffer tank 3 is connected to the condensate drain of the regular blowdown expansion vessel. Taking a subcritical unit as an example, the general quality of the boiler regular blowdown water is: pH 9.0 - 9.7, conductivity ≤ 15 us / ml, which is far better than the quality of desulfurization waste liquid. The condensate drain of the regular blowdown expansion vessel is mixed with the desulfurization slurry overflowing into the buffer tank 3, thereby reducing the concentration of the desulfurization slurry and reducing the frequency of dosing treatment, thus reducing the cost of dosing treatment.

[0022] A first valve 14 is provided on the pipeline between the liquid outlet of the buffer tank 3 and the lift pump 4.

[0023] A first buffer liquid shunt valve 15 is provided on the first buffer liquid shunt pipe 9, a second buffer liquid shunt valve 16 is provided on the second buffer liquid shunt pipe 10, and a third buffer liquid shunt valve 17 is provided on the third buffer liquid shunt pipe 11. According to the buffer liquid in the buffer tank 3, it returns to the tower through the lift pump 4 and serves as a supplement for the moisture evaporation consumption of the desulfurization tower body. When there is a need for coke quenching during the intermittent coking in the coking plant, the desulfurization waste liquid temporarily stored in the buffer tank 3 can be used for wet coke quenching through valve switching, reducing or emptying the liquid level of the buffer tank 3 to leave an adjustment margin for storing new waste liquid later. Only when the buffer tank 3 is at a high liquid level, with a high ion concentration and a low pH, and it is unable to continue storing new desulfurization waste liquid and has poor water quality (generally when the chloride ion concentration > 10,000 mg / L and pH < 6), the waste liquid in the buffer tank 3 is treated by the dosing system.

[0024] A second valve 18 is provided on the pipeline between the sludge outlet of the clarifying tank 2 and the diaphragm pump 5. A third valve 19 is provided on the pipeline between the diaphragm pump 5 and the feed inlet of the plate and frame filter press 6.

[0025] The utility model applies the desulfurization slurry to the wet coke quenching process to complete the waste utilization of the desulfurization slurry. When there is no need for the wet coke quenching process, the desulfurization slurry is preferentially returned to the desulfurization tower for treatment. Only when the desulfurization slurry has no utilization value is it finally treated by dosing, which greatly reduces the negative pressure of the dosing system operation, reduces the cost of dosing treatment, and also significantly reduces the failures of the dosing system, reducing the maintenance cost of the dosing system and extending the service life of the equipment; it recovers the boiler blowdown flash tank drain water and reduces the desulfurization slurry concentration, forming a good internal circulation, further reducing the desulfurization slurry dosing treatment cost while achieving waste utilization; and because the buffer liquid in the buffer tank is finally treated by dosing only when its concentration reaches a certain index, the concentration standard of the buffer liquid for dosing treatment is stable, the dosing amount is stable, and the requirements for operators are low.

[0026] The above is only a preferred embodiment of the utility model and does not impose any form of limitation on the utility model. Although the utility model has been disclosed above with the preferred embodiment, it is not intended to limit the utility model. Any person skilled in the art, without departing from the technical solution scope of the utility model, can make some changes or modifications to the above-disclosed technical content to obtain equivalent embodiments of equivalent changes. However, as long as it does not depart from the technical solution content of the utility model and is based on the technical essence of the utility model, any simple modification, equivalent replacement, and improvement made to the above embodiments within the spirit and principle of the utility model still fall within the protection scope of the technical solution of the utility model.

Claims

1. A desulfurization slurry treatment system, characterized in that: It includes a desulfurized slurry input pipe, a clarification tank, a buffer tank, a lift pump, a diaphragm pump and a plate and frame filter press. The desulfurized slurry input pipe is connected to the liquid inlet of the clarification tank through a first desulfurized slurry shunt pipe. The desulfurized slurry input pipe is connected to wet coke quenching through a second desulfurized slurry shunt pipe. The supernatant liquid outlet of the clarification tank is connected to the first liquid inlet of the buffer tank through a pipe. The liquid outlet of the buffer tank is connected to one end of the lift pump through a pipe. The other end of the lift pump is connected to one end of a first buffer liquid shunt pipe, a second buffer liquid shunt pipe and a third buffer liquid shunt pipe respectively through pipes. The other end of the first buffer liquid shunt pipe is connected to a desulfurization tower. The other end of the second buffer liquid shunt pipe is connected to wet coke quenching. The other end of the third buffer liquid shunt pipe is connected to a dosing system. The sludge outlet of the clarification tank is connected to one end of the diaphragm pump through a pipe. The other end of the diaphragm pump is connected to the feed inlet of the plate and frame filter press through a pipe. The filtrate outlet of the plate and frame filter press is connected to the third liquid inlet of the buffer tank through a pipe.

2. The desulfurization slurry treatment system according to claim 1, wherein: A first shunt valve is arranged on the first desulfurized slurry shunt pipe, and a second shunt valve is arranged on the second desulfurized slurry shunt pipe.

3. A desulfurization slurry treatment system according to claim 1, characterized in that: The supernatant liquid outlet of the clarification tank is an overflow port.

4. A desulfurization slurry treatment system according to claim 1, characterized in that: The second liquid inlet of the buffer tank is connected to the condensate drain of a continuous blowdown flash tank.

5. A desulfurization slurry treatment system according to claim 1, wherein: A first valve is arranged on the pipe between the liquid outlet of the buffer tank and the lift pump.

6. A desulfurization slurry treatment system according to claim 1, characterized in that: A first buffer liquid shunt valve is arranged on the first buffer liquid shunt pipe, a second buffer liquid shunt valve is arranged on the second buffer liquid shunt pipe, and a third buffer liquid shunt valve is arranged on the third buffer liquid shunt pipe.

7. A desulfurization slurry treatment system according to claim 1, characterized in that: A second valve is arranged on the pipe between the sludge outlet of the clarification tank and the diaphragm pump.

8. A desulfurization slurry treatment system according to claim 1, characterized in that: A third valve is arranged on the pipe between the diaphragm pump and the feed inlet of the plate and frame filter press.

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