WO2008092374A1

WO2008092374A1 - A belt-type agitating multilevel sludge drying device with recycled secondary steam

Info

Publication number: WO2008092374A1
Application number: PCT/CN2008/000161
Authority: WO
Inventors: Zhixiao Zhang
Original assignee: Zhixiao Zhang
Priority date: 2007-01-26
Filing date: 2008-01-23
Publication date: 2008-08-07
Also published as: CN201010609Y

Abstract

A belt-type agitating multilevel sludge drying device with recycled secondary steam, includes a main body (4), a feeding mechanism provided on the top of the main body (4), and a discharging mechanism provided at the bottom of the main body (4). A hopper (1) is set on the feeding mechanism. Multi-layer rectangle hollow trays are provided inside the main body (4). Three rims of the hollow tray are connected in matching and fixed way with the inner wall of the main body (4). Another rim forms a discharging outlet (5) with the inner wall of the main body (4). The discharging outlet (5) of each layer of hollow tray is alternately provided on the two opposite rims of the hollow tray. A sludge evaporator cell (11) is set in the space over each layer of the hollow tray. The hollow tray comprises a top heating board (10) and a bottom separating board (8). The top heating board (10) and the bottom separating board (8) are connected by vertical baffles (9) to form a heating source media flow passage (6). The start edge of the heating source media flow passage (6) in bottom layer is connected to a heat source by pipeline. The sludge evaporator cell (11) in top layer is connected to outside by pipeline. The start edges of the heating source media flow passages (6) in other layersare connected to the lower sludge evaporator cells (11) by pipeline. A belt-type delivery mechanism (3) is provided on the upper portion of each layer of hollow tray.

Description

Multi-stage secondary steam reuse drying device with belt type stirring sludge

The utility model relates to a sludge drying device, in particular to a multi-stage secondary steam recycling drying device with belt type stirring sludge.

Background technique

The sludge heat treatment has a high capacity reduction rate, and the sludge can be disposed in a large amount and quickly, and is harmless and thoroughly developed in recent years. However, due to the wet sludge after mechanical dewatering, the water content is as high as about 80%, and the calorific value is very low. If it is directly incinerated, 304~565L of heavy oil should be added per ton of dry-based sludge, which consumes a lot of energy. The dried sludge has a higher calorific value and can approach the calorific value of the inferior coal. Therefore, heating and dehydrating the sludge after mechanical dewatering and increasing the calorific value of the sludge are the key technologies for sludge fueling.

The existing belt type sludge single-stage drying device is composed of a sludge agitation conveying machine, a heating chamber and an evaporation chamber. The sludge sent to the evaporation chamber is heated by the agitation conveyor to the heat exchange chamber, and the secondary steam is evaporated in the evaporation chamber to be dried. The heat source of the heating chamber is provided by a heating system external to the device, and the secondary steam is provided by A separate cooling system outside the unit condenses into water and a small amount of exhaust. Using a single-stage drying device, the thermal energy of lkg water vapor can only evaporate about lkg of sludge water. The secondary steam generated by sludge evaporation still has a relatively high calorific value, but it is not conducive to transportation due to its low pressure. And the presence of contaminants in which the applicability is limited, etc., is directly taken out of the drying device for condensation treatment, and its energy is not fully utilized, resulting in a large loss of heat energy in the drying system. Therefore, the development of an energy-saving sludge drying device is an important part of the sludge fueling technology, and it is critical to realize sludge recycling, reduction, and harmlessness.

Summary of the invention

The purpose of the utility model is to provide a novel belt-type mixed sludge multi-stage secondary steam reuse drying device with high efficiency, low energy consumption, low investment, and convenient continuous large-scale production in view of the deficiencies of the prior art.

The utility model comprises a body. The top of the body is provided with a feeding mechanism, the bottom is provided with a discharging mechanism, and the feeding mechanism is provided with a hopper. The multi-layer rectangular hollow tray is arranged flat in the body, the three edges of the hollow tray are matched and fixedly connected with the inner wall, and the other edge forms a discharge opening with the inner wall, and the outlet of each hollow tray is arranged at a hollow interval. The two edges of the tray correspond. Empty per floor The space above the heart tray is the sludge evaporation chamber. The hollow tray as a sludge heating chamber includes a top heating plate and a bottom portion partition plate, and the heating plate and the partition plate are connected by a baffle plate in a vertical direction. The baffle is serpentine or labyrinth, and the heating plate, the partition plate and the baffle are enclosed to form a serpentine or labyrinth heat source medium flow channel. The starting end of the heat source medium flow channel in the hollow tray of the bottom layer communicates with the heat source through the pipeline, and the sludge evaporation chamber of the top layer communicates with the outside through the pipeline. The starting end of the heat source medium flow passage in the remaining hollow trays is connected to the sludge evaporation chamber below it through a pipeline. A belt conveyor is disposed on the upper portion of each hollow tube.

The feeding mechanism is one of a screw conveyor, a scraper conveyor, a chain conveyor, a belt conveyor, and a piston push rod.

The discharging mechanism is one of a screw conveyor, a scraper conveyor, a chain conveyor, a belt conveyor, and a piston push rod.

The belt conveying device is one of a chain conveyor, a steel belt conveyor and a mesh belt conveyor, and the feeding direction is a direction toward the discharge opening.

The terminating end of the heat source medium flow passage in each of the hollow trays is provided with a drain pipe and an exhaust pipe which communicate with the outside.

The multi-stage secondary steam reuse drying device with belt type agitating sludge of the utility model realizes the directed conveying of sludge by means of mechanical agitation, and can realize the heat exchange stroke of the sludge and the heat exchange of the multi-stage secondary steam heating chamber. The utility model only participates in the heat exchange of the final heating chamber with a small amount of external heating source, and indirectly heats the sludge in the final evaporation chamber to evaporate the secondary steam of the sludge, and the secondary steam is reused as the upper heating chamber. The heat source participates in the heat exchange of the upper heating chamber; and so on, the secondary steam of the evaporation chamber at each level is utilized step by step until the first stage evaporation chamber. The sludge is gradually evaporated in the evaporation chamber of each stage and gradually dried. The secondary steam in the evaporation chamber of each level is reused to participate in the heat exchange of the upper heating chamber, and is condensed into water and a small amount of exhaust gas, and the hydrophobic and exhaust gases are discharged from the device. The secondary vapor of the first stage evaporation chamber can be directly discharged and cooled by the condenser to water and a small amount of tail gas. Since the exhaust gas has a foul odor, it needs to be sent to the deodorization system for purification. After the secondary steam is concentrated, it is disposed of separately. The utility model fully utilizes the secondary steam of the multi-stage evaporation chamber to make the external heating source energy of 1kg of water vapor, and can evaporate about 2~5kg of sludge water, and the energy saving effect is very remarkable.

DRAWINGS

1 is a schematic structural view of an embodiment of the present invention;

Figure 2 is a cross-sectional view of the A-A of Figure 1.

detailed description As shown in FIG. 1 and FIG. 2, the belt-type agitated sludge multi-stage secondary steam reuse drying device of the present invention comprises a sealed body 4 which is externally insulated. A screw conveyor 2 and a hopper 1 are disposed at the upper end of the body 4, and a screw conveyor 7 is disposed at the lower end of the body 4. Three layers of hollow trays are horizontally disposed in the body 4, and a space above each of the hollow trays is a sludge evaporation chamber 11. The hollow tray as a sludge heating chamber includes a top heating plate 10 and a bottom portion partition 8, which is connected to the partition plate 8 by a labyrinth baffle 9 in the vertical direction. The heating plate 10, the partitioning plate 8, and the baffle 9 are enclosed to form a labyrinth heat source medium flow path 6. The three edges of each hollow tray are matched and fixedly connected with the inner wall of the body 4, and the other edge forms a discharge opening 5 with the inner wall of the body 4, wherein the outlets 5 of the top and bottom layers are in the same position, and the position of the discharge opening 5 of the intermediate layer is The opposite. A chain conveyor 3 is disposed on the upper portion of each hollow tube, and the feeding direction is the direction toward the discharge opening 5. The starting end of the heat source medium flow path 6 in the hollow tray of the bottom layer communicates with the heat source through the pipeline, and the sludge evaporation chamber 11 of the top layer communicates with the outside through the pipeline. The starting end of the heat source medium flow passage 6 in the hollow tray of the top layer and the intermediate layer is connected to the sludge evaporation chamber 11 below it through a pipeline, and the end of the heat source medium flow passage 6 is provided with a discharge pipe and an exhaust pipe which communicate with the outside. .

The specific workflow is as follows:

Step 1: The sludge is sent to the sludge secondary steam to be reused in the drying device hopper.

Step 2: The sludge is continuously fed into the primary sludge evaporation chamber by means of a screw conveyor under the hopper.

Step 3: The sludge in the first-stage sludge evaporation chamber is transported by the chain conveyor, the sludge is laid on the heating plate and continuously turned, and the sludge absorbs the heat energy of the first-stage heating chamber while moving along the heating plate, and evaporates. The secondary steam is discharged, and the sludge is turned to the discharge port, and is dropped by gravity into the secondary evaporation chamber. The secondary vapor of the primary evaporation chamber can be directly exported from the pipeline. The sludge was first dried.

Step 4: The sludge in the secondary evaporation chamber is transported by the chain conveyor, the sludge is laid on the heating plate and continuously turned, and the sludge absorbs the heat energy of the secondary heating chamber while moving along the heating plate, and evaporates The secondary steam, and the sludge is turned to the discharge port, and is dropped by gravity into the tertiary evaporation chamber. The secondary vapor of the stage evaporation chamber is connected to the beginning of the heat source medium flow path of the primary heating chamber through the pipeline. Therefore, the secondary steam of the stage is introduced into the primary heating chamber for use as a heat source to participate in the heat exchange of the heating plate, and the exhaust gas after the heat exchange is led out by the exhaust pipe, and the hydrophobicity is led out by the discharge pipe. The sludge was dried in two stages.

Step 5: The sludge in the third-stage evaporation chamber is transported by the chain conveyor, the sludge is laid on the heating plate and continuously turned, and the sludge absorbs the heat energy of the three-stage heating chamber along the movement of the heating plate, and evaporates two Secondary steam, and the sludge is turned to the discharge port, which is dropped by gravity into the silo, and the dried product is The screw conveyor is sent out to complete the entire sludge drying process. The secondary vapor of the stage evaporation chamber is connected to the beginning end of the heat source medium flow path of the secondary heating chamber through a pipeline. Therefore, the secondary steam of the stage is introduced into the secondary heating chamber for use as a heat source to participate in the heat exchange of the heating plate, and the exhaust gas after the heat exchange is led out by the exhaust pipe, and the hydrophobicity is led out by the discharge pipe. The sludge was dried in three stages. Since the heating chamber of this stage is the final stage, it is necessary to connect external external heating sources such as steam, heat transfer oil, flue gas and hot air through pipes.

The multi-stage secondary steam reuse drying device of the belt type agitating sludge of the utility model has the advantages that compared with the existing sludge drying device,

(1) The belt type agitation conveying structure is adopted, and the secondary steam of the sludge can be reused for multi-stage drying, the system is simple and reliable, the installation power of the device is low, and the power consumption of the plant is saved.

(2) The secondary steam exporting process of sludge is short, the resistance is small, and it is not easy to recondense and liquefy in the evaporation chamber to make the sludge return to moisture.

(3) The stirring surface covers the heating plates at all levels, and the surface of the plate is not easy to bond.

(4) The oxygen content of the device is very low, which reduces the danger of spontaneous combustion and explosion of dust. The external heating source is heated indirectly, and the amount of exhaust gas treatment is small.

(5) The secondary steam energy of the sludge in the multi-stage evaporation chamber is fully utilized, so that the sludge drying is limited by the external heating source, and the energy saving effect is very remarkable.

(6) The granulation is not required before the sludge enters the drying unit, which greatly simplifies the drying system.

(7) The drying device is in a negative pressure operation state, and no odor is leaked.

(8) The material has wide adaptability and is suitable for drying (including granulation) of various chemical products and mineral products, especially suitable for slurry materials.

(9) Easy to adjust. By changing the number of stages, the type of mixing mechanism, the stirring speed, etc., the residence time of the sludge material is adjusted to meet the requirements of the dry product.

Claims

Claim

1. A multi-stage secondary steam reuse drying device with a belt type agitating sludge, comprising a body, characterized in that a feeding mechanism is arranged at the top of the body, a discharging mechanism is arranged at the bottom, and a hopper is arranged on the feeding mechanism; The tray plane is disposed in the body, the three edges of the hollow tray are matched and fixedly connected with the inner wall of the body, and the other edge forms a discharge port with the inner wall of the inner wall, and the outlet of each hollow tray is arranged at intervals corresponding to the hollow tray. Two edges; the space above each hollow tray is a sludge evaporation chamber; the hollow tray serves as a sludge heating chamber including a top heating plate and a bottom partition, and the heating plate and the partition plate are connected by a vertical baffle The baffle plate is serpentine or labyrinth, and the heating plate, the partition plate and the baffle plate are enclosed to form a serpentine or labyrinth heat source medium flow channel; the heat source medium flow channel in the bottom hollow plate The beginning end communicates with the heat source through the pipeline, and the sludge evaporation chamber of the top layer communicates with the outside through the pipeline; the starting end of the heat source medium flow passage in the remaining hollow trays and the sludge evaporation below it It communicates through a line; hollow upper portion of each tray is provided with a belt conveyor apparatus.

2. The belt-type agitated sludge multi-stage secondary steam reuse drying device according to claim 1, wherein the feeding mechanism is a screw conveyor, a scraper conveyor, a chain conveyor, and a belt conveyor. One of the machine and piston push rods.

3. The belt-type agitated sludge multi-stage secondary steam reuse drying device according to claim 1, wherein the discharging mechanism is a screw conveyor, a scraper conveyor, a chain conveyor, and a belt conveyor. One of the machine and piston push rods.

4. The belt type agitating sludge multi-stage secondary steam recycling drying device according to claim 1, wherein the belt conveying device is a chain conveyor, a steel belt conveyor, and a mesh belt conveyor. One type, the feeding direction is the direction of the discharge port.

5. The belt-type agitated sludge multi-stage secondary steam reuse drying apparatus according to claim 1, wherein the end of the heat source medium flow passage in each of the hollow trays is provided with a connection with the outside. Drain pipe and exhaust pipe.