Sludge thin-layer waste heat drying device

Abstract

The utility model discloses a sludge thin-layer waste heat drying device. The sludge thin-layer waste heat drying device comprises a sealing cover, a sludge conveying pipeline, a distributor, a fan, a cooler and a conveyor, the conveyor is arranged on the lower side of the rotary kiln, the sealing cover is installed outside the rotary kiln, the sealing cover is located between the rotary kiln and the conveyor, and a closed space is defined by the sealing cover between the rotary kiln and the conveyor; the tail end of the sludge conveying pipeline is provided with a distributor, the distributor is arranged above the rotary kiln and penetrates into the sealing cover from the outside, an outlet of the distributor is provided with a discharging scraper and a distributing scraper which are oppositely arranged, and the distributing scraper is located on the rotating direction side of the rotary kiln; and the closed space in the sealing cover, the cooler, the fan and the rotary kiln are connected through a plurality of sections of ventilation pipelines. The device is reasonable in structural design, the outer surface of the rotary kiln serves as heat exchange equipment, the outer surface of the rotary kiln serves as a drying face, and the waste heat utilization rate is high; and in ingenious combination with the design of the rotary kiln, operation is convenient, the drying efficiency is high, and the application prospect is good.

Description

Technical Field

[0001] This utility model relates to the field of solid waste recycling technology, and to a sludge thin-layer waste heat drying device, and particularly to a device that fully utilizes the waste heat of a rotary kiln for sludge thin-layer drying. Background Technology

[0002] Sludge drying, also known as sludge dewatering, refers to the process of removing most of the water content from sludge through processes such as leaching or evaporation. It generally refers to the use of self-evaporation facilities such as sludge drying beds. After sludge thickening, physical methods are used to further reduce the water content of the sludge, facilitating its transportation, storage, utilization, or further treatment.

[0003] Mechanical dewatering is generally used as the first step in dewatering sludge due to its high efficiency and short processing time. However, the moisture content of the mechanically dewatered sludge is still above 78%. Further dewatering is necessary, and thermal drying is commonly used for this purpose. Thermal drying removes moisture from the dewatered sludge through heat transfer between the sludge and the heat medium, reducing its volume. After drying, the odor, pathogens, viscosity, and instability of the sludge are significantly improved, making it suitable for use as fertilizer, soil conditioner, building materials, landfill, as an alternative energy source, or for further refining into oil or gas for chemical products. Since thermal drying requires a large heat source, it is usually combined with waste heat utilization to reduce energy consumption. In practice, biogas heat generated during anaerobic digestion of sludge, waste heat from garbage and sludge incineration, waste heat from thermal power plants, or other waste heat are often used to dry the sludge.

[0004] Currently, waste heat utilization methods all use gas / liquid as the heat transfer medium to transport heat energy to drying equipment to dry sludge. Although this can effectively utilize waste heat, the heat transfer process will result in a large amount of waste heat waste, which will greatly affect the waste heat utilization rate.

[0005] Therefore, developing a sludge waste heat drying device with high waste heat utilization rate and convenient operation is of great practical significance. Utility Model Content

[0006] Due to the aforementioned deficiencies in the existing technology, this utility model provides a sludge waste heat drying device with high waste heat utilization rate and convenient operation, specifically a device that fully utilizes the waste heat of a rotary kiln for thin-layer sludge drying.

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] A sludge thin-layer waste heat drying device includes a sealing cover, a sludge conveying pipeline, a distributor, a fan, a cooler, and a conveyor.

[0009] The conveyor is arranged on the lower side of the rotary kiln and the direction of the conveyor is parallel to the rotation axis of the rotary kiln. The sealing cover is installed on the outside of the rotary kiln and is located between the rotary kiln and the conveyor, forming a closed space between the rotary kiln and the conveyor.

[0010] The sludge conveying pipeline is equipped with a distributor at its end. The distributor is arranged above the rotary kiln and passes through the sealing cover from the outside. The distributor outlet is equipped with a discharge scraper and a distribution scraper. The distribution scraper is located on the side of the rotary kiln in the direction of rotation and the discharge scraper is located on the opposite side of the distribution scraper.

[0011] One end of the fan is connected to the rotary kiln through ventilation duct three, and the other end is connected to the cooler through ventilation duct two. The end of the cooler away from ventilation duct two is connected to the sealed space inside the sealing cover through ventilation duct one.

[0012] The operation process of the above-mentioned sludge thin-layer waste heat drying device is as follows:

[0013] Sludge is transported to the distributor via a sludge conveying pipe. Under the action of the distributor scraper, the sludge is evenly spread on the outer surface of the rotary kiln as it rotates, forming a thin sludge layer of 1-5 mm. As the kiln rotates, the moisture in the sludge is heated and evaporated. When the rotary kiln completes one revolution, it reaches the front end of the distributor. Under the action of the discharge scraper, the dried sludge layer is scraped onto the conveyor below and sent out, completing one drying cycle. The sludge layer waste heat drying device continues the spreading, spreading, and drying process for the next drying cycle. The exhaust gas generated during the drying process is condensed and dehumidified through ventilation pipes and coolers before being sent into the rotary kiln for incineration, thereby eliminating the impact of odor from the drying process on the environment.

[0014] Large rotary kilns can have a diameter of over 3.0m and a length of over 60m, with an outer surface area of ​​up to 424m². 2 Furthermore, the outer surface temperature of the rotary kiln can reach 300℃, and the thermal resources are abundant. The above-mentioned equipment can make full use of the waste heat of the rotary kiln.

[0015] This utility model of a sludge thin-layer waste heat drying device has a reasonable structural design. It uses the outer surface of a rotary kiln as a heat exchange device, directly modifying the rotary kiln and using the outer surface of the rotary kiln as the drying surface. It does not require a medium to transfer heat, has a high waste heat utilization rate, and makes full use of the characteristics of the rotary kiln itself to complete the sludge spreading and unloading. It is cleverly combined with the design of the rotary kiln itself, is easy to operate, has high drying efficiency, and has great application prospects.

[0016] As a preferred technical solution:

[0017] As described above, in a sludge thin-layer waste heat drying device, after the fan is started, the ventilation direction of the ventilation duct is through ventilation duct one, ventilation duct two, and ventilation duct three to the rotary kiln, so that the waste gas generated during drying is sent into the rotary kiln for incineration, thereby reducing environmental pollution.

[0018] In the sludge thin-layer waste heat drying device described above, a high-level alarm is installed on the distributor.

[0019] The sludge thin-layer waste heat drying device described above includes a cooler comprising independent but contacting liquid and gas paths.

[0020] The inlet of the liquid circuit is connected to the cold water inlet pipe, and the outlet is connected to the hot water outlet pipe;

[0021] The inlet of the air passage is connected to ventilation duct one, and the outlet is connected to ventilation duct two.

[0022] As described above, in a sludge thin-layer waste heat drying device, the cooler has a drain pipe connected to the gas path. The exhaust gas in the gas path may produce condensate after cooling, which can be discharged from the cooler's gas path through the drain pipe.

[0023] In the sludge thin-layer waste heat drying device described above, the conveyor is a belt conveyor.

[0024] The above technical solution is only one feasible technical solution of this utility model. The protection scope of this utility model is not limited to this. Those skilled in the art can reasonably adjust the specific design according to actual needs.

[0025] Compared with the prior art, the above-mentioned utility model has the following advantages or beneficial effects:

[0026] (1) The sludge thin-layer waste heat drying device of this utility model has a reasonable structural design. It uses the outer surface of the rotary kiln as a heat exchange device, directly modifies the rotary kiln, and uses the outer surface of the rotary kiln as the drying surface. It does not require a medium to transfer heat and has a high waste heat utilization rate.

[0027] (2) The sludge thin-layer waste heat drying device of this utility model makes full use of the characteristics of the rotary kiln itself to complete the sludge spreading and unloading. It is cleverly combined with the design of the rotary kiln itself, making it easy to operate and efficient in drying operations.

[0028] (3) The sludge thin-layer waste heat drying device of this utility model uses ventilation pipes and coolers to send the waste gas generated in the drying process into the rotary kiln for incineration after condensation and dehumidification, thereby eliminating the impact of malodor on the environment during the drying process. It is reasonably designed, environmentally friendly, and has great application prospects. Attached Figure Description

[0029] The present invention, its features, shape, and advantages will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. Like reference numerals denote like parts throughout the drawings. The drawings are not drawn strictly to scale; the focus is on illustrating the main idea of ​​the invention.

[0030] Figure 1 This is a schematic diagram of the sludge thin-layer waste heat drying device of this utility model.

[0031] Figure 2 This is a schematic cross-sectional view of the sealing cover of the sludge thin-layer waste heat drying device of this utility model (the arrow in the figure indicates the rotation direction of the rotary kiln).

[0032] Among them, 1 is a rotary kiln, 2 is a sludge conveying pipe, 3 is a material distributor, 4 is a sealing cover, 5 is a belt conveyor, 6 is a ventilation duct one, 7 is a sewage discharge pipe, 8 is a cooler, 9 is a ventilation duct two, 10 is a fan, 11 is a ventilation duct three, 12 is a cold water inlet pipe, 13 is a hot water outlet pipe, 14 is a high material level alarm, 15 is a discharge scraper, and 16 is a material distribution scraper. Detailed Implementation

[0033] The structure of this utility model will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the utility model.

[0034] Example 1

[0035] A sludge thin-layer waste heat drying device, such as Figures 1-2 As shown, it includes a sealing cover 4, a sludge conveying pipe 2, a material distributor 3, a blower 10, a cooler 8, and a belt conveyor 5;

[0036] The belt conveyor 5 is arranged on the lower side of the rotary kiln 1 and the arrangement direction of the belt conveyor 5 is parallel to the rotation axis of the rotary kiln 1. The sealing cover 4 is installed on the outside of the rotary kiln 1. The sealing cover 4 is located between the rotary kiln 1 and the belt conveyor 5 and forms a closed space between the rotary kiln 1 and the belt conveyor 5.

[0037] A distributor 3 is installed at the end of the sludge conveying pipe 2. The distributor 3 is arranged above the rotary kiln 1 and passes through the sealing cover 4 from the outside. A high material level alarm 14 is installed on the distributor 3. A discharge scraper 15 and a distribution scraper 16 are installed at the outlet of the distributor 3. The distribution scraper 16 is located on the side of the rotary kiln 1 in the direction of rotation and the discharge scraper 15 is located on the opposite side of the distribution scraper 16.

[0038] One end of the blower 10 is connected to the rotary kiln 1 through ventilation duct 3 11, and the other end is connected to the cooler 8 through ventilation duct 2 9. The end of the cooler 8 away from ventilation duct 2 9 is connected to the sealed space inside the sealing cover 4 through ventilation duct 1 6. After the blower 10 is started, the ventilation direction of the ventilation duct is through ventilation duct 1 6, ventilation duct 2 9, and ventilation duct 3 11 to the rotary kiln 1.

[0039] The cooler 8 includes independent but contacting liquid and gas circuits; the inlet of the liquid circuit is connected to the cold water inlet pipe 12, and the outlet is connected to the hot water outlet pipe 13; the inlet of the gas circuit is connected to the ventilation duct 1 6, and the outlet is connected to the ventilation duct 2 9; the cooler 8 has a drain pipe 7, which is located on the gas circuit.

[0040] The operation process of the sludge thin-layer waste heat drying device of this utility model is as follows:

[0041] Sludge is transported to the distributor via a sludge conveying pipe. Under the action of the distributor scraper, the sludge is evenly spread on the outer surface of the rotary kiln as it rotates, forming a thin sludge layer of 1-5 mm. As the kiln rotates, the moisture in the sludge is heated and evaporated. When the rotary kiln completes one revolution, it reaches the front end of the distributor. Under the action of the discharge scraper, the dried sludge layer is scraped onto the conveyor below and sent out, completing one drying cycle. The sludge layer waste heat drying device continues the spreading, spreading, and drying process for the next drying cycle. The exhaust gas generated during the drying process is condensed and dehumidified through ventilation pipes and coolers before being sent into the rotary kiln for incineration, thereby eliminating the impact of odor from the drying process on the environment.

[0042] Verification has shown that the sludge thin-layer waste heat drying device of this utility model has a reasonable structural design. It uses the outer surface of the rotary kiln as a heat exchange device, directly modifying the rotary kiln and using the outer surface of the rotary kiln as the drying surface. It eliminates the need for a medium to transfer heat, resulting in high waste heat utilization. It fully utilizes the characteristics of the rotary kiln itself to complete the sludge spreading and unloading. It is cleverly integrated with the design of the rotary kiln itself, making it easy to operate and highly efficient in drying operations. The exhaust gas generated during the drying process is condensed and dehumidified using ventilation ducts and coolers before being sent into the rotary kiln for incineration, thereby eliminating the impact of odors from the drying process on the environment. The design is reasonable, environmentally friendly, and has great application prospects.

[0043] Those skilled in the art should understand that variations can be implemented by combining existing technology with the above embodiments, which will not be elaborated here. Such variations do not affect the substantive content of this utility model, and will not be elaborated here.

[0044] The preferred embodiments of this utility model have been described above. It should be understood that this utility model is not limited to the specific embodiments described above. Devices and structures not described in detail herein should be understood as being implemented in a conventional manner within the art. Any person skilled in the art can make many possible variations and modifications to the technical solutions of this utility model using the disclosed methods and techniques, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the technical solution of this utility model. This does not affect the essential content of this utility model. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model, without departing from the content of the technical solution of this utility model, still fall within the protection scope of the technical solution of this utility model.

Claims

1. A sludge thin-layer waste heat drying device, characterized in that: Includes sealing covers, sludge conveying pipelines, material distributors, fans, coolers, and conveyors; The conveyor is arranged on the lower side of the rotary kiln and the direction of the conveyor is parallel to the rotation axis of the rotary kiln. The sealing cover is installed on the outside of the rotary kiln and is located between the rotary kiln and the conveyor, forming a closed space between the rotary kiln and the conveyor. The sludge conveying pipeline is equipped with a distributor at its end. The distributor is arranged above the rotary kiln and passes through the sealing cover from the outside. The distributor outlet is equipped with a discharge scraper and a distribution scraper. The distribution scraper is located on the side of the rotary kiln in the direction of rotation and the discharge scraper is located on the opposite side of the distribution scraper. One end of the fan is connected to the rotary kiln through ventilation duct three, and the other end is connected to the cooler through ventilation duct two. The end of the cooler away from ventilation duct two is connected to the sealed space inside the sealing cover through ventilation duct one.

2. The sludge thin-layer waste heat drying device according to claim 1, characterized in that, After the fan is started, the ventilation direction of the ventilation duct is through ventilation duct one, ventilation duct two, and ventilation duct three to the rotary kiln.

3. The sludge thin-layer waste heat drying device according to claim 1, characterized in that, The material feeder is equipped with a high material level alarm.

4. The sludge thin-layer waste heat drying device according to claim 1, characterized in that, The cooler includes independent but contacting liquid and gas passages; The inlet of the liquid circuit is connected to the cold water inlet pipe, and the outlet is connected to the hot water outlet pipe; The inlet of the air passage is connected to ventilation duct one, and the outlet is connected to ventilation duct two.

5. The sludge thin-layer waste heat drying device according to claim 4, characterized in that, The cooler has a drain pipe that is connected to the air passage.

6. The sludge thin-layer waste heat drying device according to claim 1, characterized in that, The conveyor is a belt conveyor.

Images