Sludge disc drying and vacuum drying two-stage drying system

Abstract

The utility model provides a kind of sludge disc drying and vacuum drying two-stage drying system, including dryer, the one end of the dryer is provided with hot water outlet, the hot water outlet is connected with hot water tank, the hot water tank is connected with drying tower and waste gas treatment system by heat exchanger, the one end of the drying tower is connected with heat exchanger by circulating water pump.The beneficial effects of the utility model are reflected in: the system recycles the steam heat energy generated by sludge heat drying, effectively utilizes the steam waste heat while reducing the circulating water consumption;It can also recover the heat of steam after sludge heat drying technology drying steam becomes hot water, effectively reduces the sludge heat drying steam consumption, reduces sludge disposal cost.

Description

Technical Field

[0001] This utility model belongs to the field of heat energy recovery and treatment technology, specifically relating to a two-stage drying system for sludge disc drying and vacuum drying. Background Technology

[0002] With the acceleration of urbanization in my country, the sewage treatment rate has been increasing year by year, and the production of wet sludge has also increased dramatically. To reduce sludge volume, facilitate storage and transportation, improve treatment efficiency, and reduce environmental pollution, sludge drying is necessary, and it is a prerequisite and key to sludge treatment and disposal technology. The basic principle of sludge drying is to evaporate the moisture in the sludge through heat conduction, convection, and radiation. The process flow includes a storage and transportation system, a drying system, exhaust gas purification and treatment, an electrical control instrumentation system, and its auxiliary systems. Specifically, wet sludge is heated by steam, hot oil, or electricity using equipment such as fluidized bed drying, belt drying, paddle drying, horizontal rotary drying, and spray drying. The resulting dry sludge is then disposed of independently or in conjunction with other treatments. The generated exhaust steam is treated and sent to the wastewater treatment system, while the exhaust gas is sent to the exhaust gas treatment system or to a boiler for primary and secondary air combustion. However, the heat generated by existing drying systems is not effectively utilized, which easily leads to energy waste. Therefore, how to reduce the cost of sludge treatment has become a technical problem that needs to be solved. Utility Model Content

[0003] To address the shortcomings of existing technologies and reduce energy consumption, this invention provides a two-stage sludge drying system consisting of disc drying and vacuum drying.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] A two-stage sludge drying system consisting of disc drying and vacuum drying includes a dryer, one end of which is provided with a hot water outlet connected to a hot water tank. The hot water tank is connected to a drying tower and a waste gas treatment system via a heat exchanger. One end of the drying tower is connected to the heat exchanger via a circulating water pump.

[0006] Preferably, one end of the hot water tank is connected to the drying tower via a first heat exchanger, and the other end of the hot water tank is connected to the waste gas treatment system via a second heat exchanger.

[0007] Preferably, a waste steam fan is provided between the second heat exchanger and the waste gas treatment system.

[0008] Preferably, the first end of the first heat exchanger is connected to the heat source inlet end of the drying tower, and the heat source outlet end of the drying tower is connected to the second end of the first heat exchanger via a circulating water pump.

[0009] Preferably, the first heat exchanger and the second heat exchanger are connected by a hot water circulation pump.

[0010] Preferably, the upper end of the drying tower is provided with a mud inlet, and one side of the mud inlet is connected to the exhaust steam treatment system.

[0011] Preferably, the upper end of the dryer is connected to the second heat exchanger via an integrated dust collector.

[0012] Preferably, the mud outlet of the dryer is equipped with a double-flip airlock.

[0013] The beneficial effects of this invention are as follows: This system can recover and utilize the waste steam heat generated by sludge thermal drying, effectively utilizing the waste steam heat while reducing the consumption of circulating water; it can also recover the heat after the steam used for sludge thermal drying is converted into hot water, effectively reducing the steam consumption of sludge thermal drying and reducing the cost of sludge disposal. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 : Schematic diagram of the system connection structure of this utility model. Detailed Implementation

[0016] This utility model discloses a two-stage sludge drying system combining disc drying and vacuum drying. Figure 1 As shown, the system includes a sludge dryer 1, with a steam inlet 13 and a hot water outlet at both ends. The dryer 1 also has a sludge inlet 12 and a sludge outlet 11 at its upper and lower ends. The sludge outlet 11 is equipped with a double-flip airlock, ensuring the entire system operates under negative pressure, preventing exhaust gas leakage, thus protecting the environment and minimizing pollution. The upper end of the dryer 1 is connected to a second heat exchanger 4 via an integrated dust collector 2. To better control the exhaust steam volume, an electric valve assembly is installed between the integrated dust collector 2 and the second heat exchanger 4. The dryer 1 is a sludge disc dryer.

[0017] In this embodiment, the hot water outlet is connected to a hot water tank 3, which is connected to a first heat exchanger 5 and a second heat exchanger 4 via pipelines. The first heat exchanger 5 and the second heat exchanger 4 are connected by a hot water circulation pump 54. The first heat exchanger is connected to the lower end port of the hot water tank 3, and the second heat exchanger 4 is connected to the top port of the hot water tank 3.

[0018] The second heat exchanger 4 is connected to the waste gas treatment system via the exhaust steam blower 8. The first end of the first heat exchanger 5 is connected to the heat source inlet of the sludge drying coil located at the bottom of the drying tower 6, and the heat source outlet of the sludge drying coil of the drying tower 6 is connected to the second end of the first heat exchanger 5 via a circulating water pump 7. A sludge inlet 61 is provided at the upper end of the drying tower 6, and one side of the sludge inlet 61 is connected to the exhaust steam treatment system.

[0019] When using this invention for sludge drying, wet sludge enters the drying tower 6 through the sludge inlet 61. The bottom of the drying tower is equipped with a sludge drying coil to heat and dry the wet sludge. The dried semi-dry sludge is then discharged from the drying tower inlet 61, and the generated exhaust steam enters the exhaust steam treatment system for processing.

[0020] Meanwhile, at the other end, when the sludge is dried using a dryer, the steam used for drying is converted into hot water after drying the wet sludge. The hot water is stored in a hot water tank 3. After passing through the first heat exchanger, the hot water transfers heat to a low-quality heat source (such as hot water) in the sludge drying coil at the bottom of the hot water tank. Then, it is pressurized by a circulating water pump. The hot water absorbs heat from the exhaust steam through the first heat exchanger 5 and returns to the hot water tank, thus repeating the cycle to fully utilize the heat. The exhaust steam generated by the dryer 1 is dusted by an integrated dust collector 2, the exhaust steam volume is regulated by an electric valve group, and the wastewater is condensed by the second heat exchanger 4 before being sent to the exhaust gas fan and entering the exhaust gas treatment system. When a low-quality heat source (such as hot water) is circulating in the drying coil, the temperature is high before entering the drying tower. After entering the drying tower to dry the wet sludge, the steam releases heat and cools down. Then, it is reheated by the low-quality heat source through the first heat exchanger 5 and re-enters the drying tower to dry the sludge, thus repeating the cycle.

[0021] This system recovers and utilizes the waste steam heat generated during sludge thermal drying, effectively utilizing the waste steam heat while reducing circulating water consumption. It can also recover the heat after the steam used for sludge thermal drying is converted into hot water, effectively reducing the steam consumption of sludge thermal drying. By combining the sludge disc drying method with the drying in the drying tower, a two-stage drying system is formed, effectively reducing the cost of sludge disposal.

[0022] Finally, it should be noted that the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] Furthermore, the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it; although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A two-stage sludge drying system consisting of disc drying and vacuum drying, characterized in that: The system includes a drying machine, one end of which is provided with a hot water outlet. The hot water outlet is connected to a hot water tank, which is connected to a drying tower and a waste gas treatment system via a heat exchanger. One end of the drying tower is connected to the heat exchanger via a circulating water pump.

2. The two-stage sludge drying system of disc drying and vacuum drying as described in claim 1, characterized in that: One end of the hot water tank is connected to the drying tower via a first heat exchanger, and the other end of the hot water tank is connected to the waste gas treatment system via a second heat exchanger.

3. The two-stage sludge drying system of disc drying and vacuum drying as described in claim 2, characterized in that: A waste steam fan is installed between the second heat exchanger and the waste gas treatment system.

4. The two-stage sludge drying system of disc drying and vacuum drying as described in claim 3, characterized in that: The first end of the first heat exchanger is connected to the heat source inlet end of the drying tower, and the heat source outlet end of the drying tower is connected to the second end of the first heat exchanger through a circulating water pump.

5. The two-stage sludge drying system of disc drying and vacuum drying as described in claim 4, characterized in that: The first heat exchanger and the second heat exchanger are connected by a hot water circulation pump.

6. The two-stage sludge drying system of disc drying and vacuum drying as described in claim 5, characterized in that: The drying tower has a mud inlet at the top, and one side of the mud inlet is connected to the exhaust steam treatment system.

7. The two-stage sludge drying system of disc drying and vacuum drying as described in claim 6, characterized in that: The upper end of the dryer is connected to the second heat exchanger via an integrated dust collector.

8. The two-stage sludge drying system of disc drying and vacuum drying as described in claim 7, characterized in that: The sludge outlet of the dryer is equipped with a double-flip airlock.

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