CN204529636U - A kind of sludge drying and incineration system relying on heat power plant - Google Patents

Abstract

The utility model discloses a sludge drying and incineration system relying on a thermal power plant, which includes a sludge drying system and a sludge mixing and incineration system, wherein the sludge drying system includes a heating system, a feeding system, a paddle Sludge dryer, exhaust steam treatment system, exhaust steam reuse system, dried sludge collection and disposal system; sludge blending and incineration system includes dried sludge blending system, dried sludge incineration system. The utility model can use the high-temperature steam produced by the power station boiler to dry the sludge, and use the dried sludge to incinerate to release heat to generate steam, and the whole process does not produce pollutants. An effective way to treat waste can produce significant social and environmental benefits, and provides a feasible path for the harmless, volume reduction and resourceful disposal of sludge.

Description

A sludge drying and incineration system relying on a thermal power plant

technical field

The utility model relates to a sludge treatment system in the field of environmental protection, in particular to a sludge drying and incineration system utilizing steam from a thermal power plant and a boiler of the power plant.

Background technique

In recent years, with the development of my country's social economy and urbanization, urban sewage has been increasing, and how to deal with sludge as a by-product of sewage treatment has become a major problem facing society today. According to statistics, by 2010, there were 2,840 urban sewage treatment plants across the country, and the statistics in 2013 show that there are currently 3,600. The annual sewage treatment capacity of these sewage treatment plants can reach 34.4 billion cubic meters. And every 10,000 tons of sewage will produce 5 tons of sludge, that is, 34.4 billion cubic meters of sewage can produce about 20 million tons of sludge, but as of 2010, the harmless treatment rate of sludge in my country is less than 25%.

The Ministry of Housing and Urban-Rural Development and the Development and Reform Commission jointly issued the "Technical Guidelines for Sludge Treatment and Disposal of Urban Sewage Treatment Plants (Trial)" clearly mentioned that "sludge treatment should give priority to the use of local cement or kiln resources in the thermal power industry" to reduce sludge treatment and disposal facilities. construction investment. Among them, the co-processing of sludge by thermal power plants can not only use the abundant steam resources of thermal power plants as drying heat sources, but also use the existing boilers and advanced waste steam treatment systems of thermal power plants, saving investment and operating costs.

Practice shows that sludge drying is a key step to realize the harmless, reduction and resource disposal of sludge. At present, the water content of sludge in sewage treatment plants is generally around 70% after mechanical dehydration, which is far from meeting the water content requirements of sludge incineration. If the traditional sludge drying and granulation system is used, although the moisture content can reach below 20%, the cost is often high. Therefore, the harmless treatment and disposal of sludge still has a long way to go.

Utility model content

The technical problem to be solved by the utility model is to provide a sludge drying and incineration system relying on thermal power plants, to provide a system for the harmless, reduction and resource disposal of sludge that not only meets the requirements of moisture content of sludge incineration but also reduces the cost. lower feasible path.

The utility model solves its technical problems through the following technical solutions:

A sludge drying and incineration system relying on a thermal power plant. The thermal power plant includes a start-up boiler and a power plant boiler 1. It is characterized in that: the superheated steam generated by the power plant boiler 1 is sequentially connected to the steam turbine 2 and the start-up boiler auxiliary steam pipeline through pipelines. With a steam header 3, the system includes a paddle type sludge dryer 4, and an auger feeder for feeding it and a finished sludge collection device 6 for collecting its finished sludge;

The paddle-type sludge dryer 4 is a type in which steam and sludge do not directly contact, and the moisture content of the dried sludge after drying is about 50%. Steam inlets, exhaust steam ( After releasing the hot steam, most of it is condensed into water) outlet, sludge inlet, sludge outlet and sludge waste gas outlet:

The steam inlet is provided with pipelines connected to the steam header 3, and the exhaust steam outlet is sequentially provided with pipelines connected to the water film dust collector 8 through the water pump 10, and the sludge inlet and outlet are connected to the auger type respectively. The feeder and the finished sludge collection device 6, the sludge waste gas outlet are provided with pipelines to connect the cyclone separator 7/water film dust collector 8 and the induced draft fan of the power station boiler 1 of the thermal power plant in turn, and the sewage of the water film dust collector 8 is discharged The outlet is provided with a pipeline connected to the utility boiler 1 .

The system also includes a dry sludge collection and disposal system, which includes a dry sludge bin 11 for collecting the dry sludge at the outlet of the dryer, a conveying machine (16) (such as a power plant transport vehicle), a coal yard (13 ) coal mixing device and coal conveyor belt (14).

The described dried sludge collection and disposal system also includes a coal pulverizer in a power plant.

The flue gas outlet of the existing power plant boiler 1 is connected to the flue gas treatment system 15 of the power plant (including desulfurization and denitrification, flue gas dust removal, etc.) by pipes, and the ash outlet of the power plant boiler 1 is sent to the cement plant by a transport device.

The auxiliary steam pipeline for starting the boiler leads high-temperature steam (about 200° C.) to the pipeline between the steam headers 3 and is equipped with a manual valve.

The body of the paddle-type sludge dryer 4 is also provided with three thermocouple temperature measuring points and corresponding sampling ports.

The system includes a sludge drying system and a sludge blending incineration system;

The sludge drying system includes a heating system, a feeding system, a paddle-type sludge dryer, a waste gas recycling system generated during the drying process, a waste steam recycling system, and a dried sludge collection and disposal system;

The heat supply system provides the heat source for the paddle-type sludge dryer, and leads high-temperature steam (about 200°C) from the auxiliary steam pipe of the start-up boiler to the steam header. The steam pipes are respectively connected to the steam inlet of the sludge dryer.

The feeding system provides untreated sludge for the paddle-type sludge dryer, and the auger-type sludge feeder is used to continuously send fresh sludge (water content above 90%) into the sludge drying Machine, at the same time, for the convenience of controlling the feeding amount, the speed of the feeding machine can be adjusted.

The paddle-type sludge dryer is the main equipment of the sludge drying system, which is responsible for drying the fresh sludge to the required moisture content. From the actual point of view, the moisture content is required to be about 50%, which can save steam and It does not affect the subsequent sludge incineration and other treatment processes. This dryer is an indirect drying equipment, and the steam does not directly contact the sludge. In addition to the sludge and steam inlet and outlet, three thermocouple temperature measuring points are set on the body. And the corresponding sampling port in order to monitor the sludge drying situation in real time and ensure the safe and stable operation of the sludge dryer.

The waste gas reuse system refers to that the waste gas produced in the process of drying sludge is sent to the induced draft fan of the power station boiler through the cyclone separator, the water film dust collector and the small fan in sequence, and enters the boiler furnace with the air for incineration treatment, and finally passes through the flue gas of the thermal power plant. The gas treatment system is vented to the atmosphere;

Most of the exhaust steam in the exhaust steam treatment system is condensed into liquid water. Because the liquid water is of high quality, it can be pumped to the water film dust collector for reuse; at the same time, the sewage discharged from the water film dust collector is directly led to the The evaporative combustion in the upper area of the boiler furnace not only ensures the reuse of high-quality water vapor, but also does not produce sewage and germs.

The dried sludge collection and disposal system is used to collect the dried sludge at the outlet of the dryer. Generally speaking, the dried sludge at the outlet can meet the particle size requirements of power plant boilers for coal powder; if the dried sludge If the sludge does not meet the particle size required by the power plant, the sludge needs to be sent to the coal mill of the power plant to be ground to the particle size required by the boiler of the power plant (just coarse grinding is enough).

The sludge blending and incineration system includes a dried sludge blending system and a dried sludge incineration system:

The dry sludge blending system refers to transporting the qualified sludge that meets the furnace particle size requirements to the coal yard. Because the sludge is more viscous than coal powder, if it is directly sent to the coal conveyor belt, it is easy to be blocked, so it is necessary to transport the sludge to the coal yard. It is first blended with coal powder in a certain proportion at the coal yard.

The dry sludge incineration system refers to sending the mixed pulverized coal and sludge to the boiler of the power plant for incineration through the coal conveyor belt of the power plant, and the flue gas generated after the combustion is treated by the flue gas treatment system of the power plant and then discharged to the atmosphere. After the ash is collected, it is sent to the cement plant for secondary use.

In this system, the high-temperature water vapor is led out from the auxiliary steam pipe of the start-up boiler of the thermal power plant into the paddle type sludge dryer, and at the same time, the sludge with a moisture content of more than 90% is sent into the sludge dryer by the auger feeder, in which the steam and The sludge is not in direct contact; the dried sludge (with a moisture content of about 50%) after drying is discharged from the sludge outlet on the dryer to the sludge collection device, and then processed by a steel ball mill, and the qualified sludge is sent to the coal mine. After being mixed with pulverized coal in a certain proportion, it is sent to the boiler of the thermal power plant for combustion along with the coal conveyor belt. The flue gas generated by the combustion of the boiler of the thermal power plant is treated by the flue gas treatment system of the thermal power plant and then discharged to the atmosphere. The ash is collected and sent to the cement plant, etc. Secondary utilization; the exhaust gas generated during the drying process is sent to the boiler induced draft fan after being treated by the cyclone separator and the water film dust collector, and sent to the boiler furnace together with the air to participate in combustion; The water is pumped to the water film dust collector for reuse.

Compared with the prior art, the utility model has the following beneficial effects:

(1) It can make full use of the superior resources of the power plant (steam, electricity, boilers, etc.), and when the sludge is incinerated by the boiler of the power plant, on the one hand, the moisture content of the dried sludge only needs to be reduced to about 50%, which greatly saves the waste The cost required for deep drying of sludge; on the other hand, the temperature of the boiler furnace is high, which can completely decompose the pathogenic bacteria and harmful substances in the sludge, and the ash can be reused.

(2) There is no need to make any changes to the power plant boiler, just install the sludge dryer next to the start-up boiler of the power plant, which has great operability and small initial investment.

(3) This system does not produce any pollutants: the waste gas generated during the drying process and sludge incineration can make full use of the advanced flue gas treatment system of the power plant, which not only ensures that the waste gas emissions generated during the sludge treatment process meet the national standards, It also saves the investment in waste steam treatment; the washing water is reused by steam condensed water, and the final sewage is sprayed into the furnace for treatment, which neither wastes water resources nor pollutes the environment.

(4) Using the high-temperature steam generated by the power station boiler to dry the sludge, and using the dried sludge to incinerate to release heat to generate steam, opened up an effective way to recycle waste and treat waste with waste, which can produce significant environmental benefits.

Description of drawings

Figure 1 is a schematic diagram of a sludge drying system;

Figure 2 is a schematic diagram of the sludge incineration system.

The direction shown by the arrow in Figure 1 and Figure 2 is the direction of movement of various substances;

The reference signs in the figure are respectively represented as: 1-power station boiler, 2-steam turbine, 3-steam header, 4-blade sludge dryer, 5-screw feeder, 6-finished sludge collection Device, 7-cyclone separator, 8-water film dust collector, 9-induced fan, 10-water pump, 11-dried sludge silo, 12-steel ball coal mill, 13-coal yard, 14-coal conveyor belt , 15-exhaust steam treatment system, 16-sludge transport vehicle.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail:

Referring to Fig. 1, it is an embodiment of a sludge drying and incineration system relying on a thermal power plant of the present invention. The thermal power plant includes a start-up boiler and a power plant boiler 1, and the superheated steam generated by the power plant boiler 1 is connected to the steam turbine 2 and the auxiliary steam pipeline of the start-up boiler in sequence through pipelines And a steam header 3, (starting boiler auxiliary steam pipeline is not drawn).

The system includes a paddle-type sludge dryer 4, an auger-type feeder for feeding it, and a finished sludge collection device 6 for collecting its finished sludge.

Paddle type sludge dryer 4 is a model with no direct contact between steam and sludge, and the moisture content of dried sludge after drying is about 50%. There are steam inlet, exhaust steam outlet, sludge Inlet, sludge outlet and sludge waste gas outlet: the steam inlet is provided with pipes connected to the steam header 3, exhaust steam (the steam outlet substance is exhaust steam, and some of it will condense into water) outlets are arranged in turn There are pipelines connected to the water film dust collector 8 through the water pump 10, the sludge inlet and outlet are respectively connected to the auger type feeder and the finished sludge collection device 6, and the outlet of sludge waste gas (not the same as exhaust steam) A pipeline is provided to connect the cyclone separator 7/water film dust collector 8 and the induced draft fan of the thermal power plant boiler 1 in sequence, and the sewage outlet of the water film dust collector 8 is provided with a pipeline to connect to the power station boiler 1.

Referring to Figure 2, the system also includes a dry sludge collection and disposal system, which includes a dry sludge bin 11 for collecting the dry sludge at the outlet of the dryer (if the pulverized coal size is unqualified, add a power plant coal mill) . Conveyor machinery (16) (such as power plant transport vehicles, directly used to deliver to the coal yard, marked in the figure), coal yard (13) coal mixing device and coal conveyor belt (14).

Start the auxiliary steam pipeline of the boiler to lead high-temperature steam (about 200°C) to the steam header 3. A manual valve is installed on the pipeline between the steam header 3; three thermocouple temperature measuring points and corresponding Q.

The paddle type sludge dryer 4 usually uses steam or heated heat transfer oil as the drying medium, adopts indirect heating, and is supplemented by paddle stirring, and the paddle design is hollow or solid.

The principle of the utility model is:

As shown in Figure 1, high-temperature water vapor is drawn from the auxiliary steam pipe of the start-up boiler into the paddle-type sludge dryer 4, and the sludge with a moisture content of more than 90% is sent into the sludge dryer 4 by the auger-type feeder 5. The steam does not directly contact the sludge, and the dried sludge (about 50%) after drying is discharged from the sludge outlet on the dryer to the sludge collection device 6, and the waste gas generated during the drying process passes through the cyclone separator 7 and After being processed by the water film dust collector 8, it is sent to the induced draft fan 9 of the boiler, and sent into the furnace of the boiler together with the air to participate in combustion;

As shown in Figure 2, the dried sludge at the outlet of the sludge dryer 4 is sent to the coal yard 13 and mixed with coal powder in a certain proportion first, and then sent to the boiler furnace for combustion along with the coal conveyor belt 14, and the smoke produced after combustion The gas is discharged to the atmosphere after passing the waste steam treatment system 15 of the power plant (it is the flue gas treatment system of the power plant, without new additions), and the ash is collected and sent to the cement plant for secondary use.

The sludge drying system specifically includes the following parts:

1. Heat supply system: provide heat source for the paddle type sludge dryer 4, the power plant boiler 1 generates water steam, enters the steam turbine 2 to work, and part of the work steam (about 200 ℃) is drawn out from the auxiliary steam pipe of the start-up boiler to the steam header 3 , A manual valve is installed between the two, and the steam pipes drawn from the steam header are respectively connected to the steam inlet of the sludge dryer 4.

, Feeding system: provide fresh sludge for the paddle type sludge dryer, and use the auger type sludge feeder 5 to continuously feed fresh sludge (with a moisture content of more than 90%) into the sludge dryer, At the same time, in order to control the feeding amount conveniently, the speed of the feeding machine can be adjusted.

1. Paddle type sludge dryer: the main equipment of the sludge drying system, which is responsible for drying the fresh sludge to the required moisture content. From the actual point of view, the moisture content is only required to be about 50%, which can save steam and reduce waste. It will affect the subsequent sludge incineration and other treatment processes. This dryer is an indirect drying equipment, and the steam does not directly contact the sludge. In addition to the sludge and steam inlet and outlet, three thermocouple temperature measuring points and corresponding sampling ports are set on the fuselage to monitor the sludge drying situation in real time and ensure the safe and stable operation of the sludge dryer.

, Exhaust steam treatment system: the exhaust gas produced in the process of drying sludge is sent to the induced draft fan 9 of the power station boiler through the cyclone separator 7, the water film dust collector 8, and the small fan in sequence, and enters the boiler furnace with the air for incineration treatment, and finally passes through the thermal power plant. The flue gas treatment system 15 is exhausted to the atmosphere.

. Spent steam reuse system: most of the exhausted steam that releases heat is condensed into liquid water. Because the liquid water is of high quality, it can be sent to the water film dust collector 8 through the water pump 10 for reuse. At the same time, the sewage discharged from the water film dust collector 8 is directly led to the upper area of the boiler furnace for evaporation and combustion, which not only ensures the reuse of high-quality water vapor, but also does not generate sewage and pathogenic bacteria.

1. Dried sludge collection and disposal system: the dried sludge bin 11 collects the dried sludge at the outlet of the dryer. From the actual situation, generally the dried sludge at the outlet can meet the particle size requirements of the power plant boiler for coal powder; if The dried sludge does not meet the particle size required by the power plant, so the sludge needs to be sent to the coal mill 12 of the power plant to be ground to the particle size required by the boiler of the power plant (just coarse grinding is enough).

The sludge blending incineration system specifically includes the following parts:

1. Dried sludge blending system: Transport the qualified sludge that meets the furnace particle size requirements to the coal yard 13, and blend it with coal powder in a certain proportion.

. Drying sludge incineration system: the mixed pulverized coal and sludge are sent to the boiler of the power plant for incineration through the coal conveying belt 14 of the power plant, and the flue gas generated after the combustion is treated by the waste steam treatment system 15 of the power plant and then discharged to the atmosphere. After the ash is collected, it is sent to the cement plant for secondary use.

Claims (6)

1. A sludge drying and incineration system relying on a thermal power plant, the thermal power plant includes a start-up boiler and a power plant boiler (1), characterized in that: the superheated steam generated by the power plant boiler (1) is provided with steam pipes to pass The steam turbine (2) and the start-up boiler auxiliary steam pipe are connected to a steam header (3), and the system includes a paddle type sludge dryer (4), and an auger type feeder for feeding it and collecting its Finished sludge collection device (6) for finished sludge; The paddle type sludge dryer (4) is equipped with a steam inlet, exhaust steam outlet, sludge inlet, sludge outlet and sludge waste gas outlet: the steam inlet is provided with a pipe connecting the steam unit The box (3) and exhaust steam outlet are successively provided with pipelines connected to the water film dust collector (8) through the water pump (10), and the sludge inlet and outlet are respectively connected to the auger type feeder and the finished sludge collection device (6), the outlet of the sludge waste gas is provided with pipelines to connect the cyclone separator (7), the water film dust collector (8) and the induced draft fan of the power station boiler (1) of the thermal power plant in sequence, and the sewage of the water film dust collector (8) The discharge port is provided with a pipeline connected to the utility boiler (1). 2. The sludge drying and incineration system relying on a thermal power plant according to claim 1, characterized in that: the paddle-type sludge dryer (4) is a dryer after drying without direct contact between steam and sludge. A model with a moisture content of about 50% in the sludge. 3. The sludge drying and incineration system relying on thermal power plants according to claim 1 or 2, characterized in that: the system also includes a dried sludge collection and disposal system, which includes collecting the dried sludge at the outlet of the dryer Mud drying sludge bin (11), conveying machinery (16), coal yard (13) coal mixing device and coal conveying belt (14). 4. The sludge drying and incineration system relying on thermal power plants according to claim 3, characterized in that: The described dried sludge collection and disposal system also includes a coal pulverizer in a power plant. 5. The sludge drying and incineration system relying on a thermal power plant according to claim 3, characterized in that: a manual valve is installed between the start-up boiler auxiliary steam pipe and the pipe from the steam header (3). 6. The sludge drying and incineration system relying on thermal power plants according to claim 4, characterized in that: the body of the paddle-type sludge dryer (4) is provided with three thermocouple temperature measuring points and corresponding sampling points mouth.