WO2008092373A1

WO2008092373A1 - Shaft type stirring mud multilevel secondary steam recycling drying device

Info

Publication number: WO2008092373A1
Application number: PCT/CN2008/000160
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: CN201000259Y

Abstract

A mud-drying device, which has a feed mechanism arranged on top of the body (11) and a bunker formed at the bottom of the body. A discharging mechanism is arranged at the bottom of the bunker. A stirring shaft (15) and multilevel hollow column plates are arranged inside the body. There are stirring arms (3) on top of the hollow column plates. The spaces above the hollow column plates severed as mud-vaporizing chambers (12). There are heat source medium flow passages consisted of heat plates (4), division plates (7) and baffle plates (5) in the hollow column plates. The staring end of each heat source medium flow passage is connected to the lower mud-vaporizing chamber by pipeline. The multi-layer hollow column plates are provieded with central discharge ports (14) and edge discharge ports (6) at interval. The heat exchange travel route of the mud effectively exchanges heat with multilevel secondary steam heating chamber, hence saves energy.

Description

Shaft-type agitated sludge multi-stage secondary steam reuse drying device

The utility model relates to a sludge drying device, in particular to a multi-stage secondary steam recycling drying device for shaft type agitating 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 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 shaft 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 shaft-type agitated 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 cylindrical body. A feeding mechanism is arranged on the top of the body, and a hopper is arranged on the feeding mechanism. The bottom of the body is shrunk into a silo, and the bottom of the silo is provided with a discharge mechanism. A stirring shaft is arranged along the shaft center in the body, and the stirring shaft is coupled with the motor. The multi-layer hollow tray is arranged flat in the body, and the edge of the hollow tray is matched with the inner wall and fixedly connected, and the hollow tray is empty above each layer. The room is a 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 spiral or labyrinth, and the heating plate, the partition plate and the baffle are enclosed to form a spiral or labyrinth heat source medium flow path. 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. The multi-layer hollow trays are arranged with a central discharge opening and a rim discharge opening, the central discharge opening is arranged at the center of the hollow tray, and the edge discharge opening is arranged at the edge of the hollow tray. A stirring arm is arranged on the upper part of each hollow tube, and the stirring arm is fixedly connected with the stirring shaft.

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 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 scraping arm is disposed in the silo, and the scraping arm is fixedly connected with the stirring shaft and corresponds to the position of the sidewall of the silo.

The stirring arm is a tweezers, wherein the dowel of the tweezers above the hollow tray provided with the central discharge port is inclined toward the center, and the dowel of the tweezers above the hollow tray provided with the edge discharge opening is inclined toward the edge.

The agitating arm is a scraper, wherein the blade of the scraper above the hollow tray provided with the central discharge port is at the inner bend, and the blade of the scraper disposed above the hollow tray provided with the edge discharge opening is at the outer bend.

The utility model relates to a multi-stage secondary steam recycling drying device for shaft-type agitated sludge, which realizes the directed transport of sludge by means of mechanical stirring, and can realize heat exchange between the sludge heat exchange stroke and 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 continuously 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. Secondary of the first stage evaporation chamber The steam can be discharged directly, 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 treatment. After the secondary steam is concentrated, it is disposed of separately. In the utility model, the secondary steam of the sludge in the multi-stage evaporation chamber is fully reused, and the energy of the external heating source equivalent to 1 kg of water vapor can be evaporated, and the sludge moisture of about 2 to 5 kg can be evaporated, 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 schematic cross-sectional view taken along line A-A of Figure 1;

Figure 3 is a schematic cross-sectional view of the B B of Figure 1.

detailed description

As shown in Fig. 1, Fig. 2 and Fig. 3, the shaft type agitated sludge multi-stage secondary steam reuse drying device of the present invention comprises a sealed body 11 which is externally insulated. A stirring shaft 15 driven by a motor 16 is provided in the body 11. At the upper end of the body 11, a screw conveyor 2 and a hopper 1, a lower end of the body 11 is contracted to form a silo 8, and a screw conveyor 10 is disposed at the bottom of the silo 8. A scraper arm 9 for anti-blocking is disposed in the silo 8, and the scraper arm 9 is fixedly coupled to the agitating shaft 15 and corresponds to the position of the side wall of the silo 8. Three hollow trays are arranged in the body 11, and the space above each hollow tray is the sludge evaporation chamber 12. The hollow tray as a sludge heating chamber includes a top heating plate 4 and a bottom portion partition plate 7, and the heating plate 4 and the partition plate 7 are connected by a spiral baffle 5 in the vertical direction. The heating plate 4, the partition plate Ί and the baffle plate 5 are enclosed to form a spiral heat source medium flow path 13. The center of the top and bottom hollow trays is provided with a central discharge opening 14, and the edge of the hollow tray of the intermediate layer is provided with an edge discharge port 6. The upper part of each hollow tube is provided with a stirring crucible 3, and the stirring crucible 3 is fixedly coupled with the stirring shaft 15, and the top and bottom stirring crucibles 3 are inclined toward the center, and the crucible of the stirring crucible 3 of the intermediate layer is inclined toward the edge. The starting end of the heat source medium flow path 13 in the hollow tray of the bottom layer communicates with the heat source through the pipeline, and the sludge evaporation chamber 12 of the top layer communicates with the outside through the pipeline. The starting end of the heat source medium flow passage 13 in the hollow tray of the top layer and the intermediate layer is connected to the sludge evaporation chamber 12 below it through a pipeline, and the end of the heat source medium flow passage 13 is provided with a discharge pipe and an exhaust pipe which communicate with the outside. tube.

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 primary sludge evaporation chamber is transported by means of agitating arms, and the sludge is flattened. Spread on the heating plate and continuously flip, the sludge absorbs the heat energy of the first heating chamber while moving along the heating plate, evaporates the secondary steam, and flips the sludge to the center discharge port, and drops to the secondary evaporation chamber by gravity. . 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 conveyed by the stirring of the stirring arm, 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 twice. The steam is turned and the sludge is turned to the edge discharge port and dropped by gravity into the tertiary evaporation chamber. The secondary vapor of the stage evaporation chamber is connected to the beginning end of the heat source medium flow path of the primary heating chamber through a pipeline. Thus, the secondary steam of this stage is introduced into the primary heating chamber for reuse 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 conveyed by the stirring of the stirring arm, and the sludge is laid on the heating plate and continuously turned. The sludge absorbs the heat energy of the third-stage heating chamber while moving along the heating plate, and evaporates twice. The steam is turned to the center discharge port, and the gravity is dropped to the silo, and the dried product is sent out by the screw conveyor to complete the entire sludge drying process. The secondary vapor of the stage evaporation chamber is connected to the beginning of the heat source medium flow path of the secondary heating chamber through a pipeline. Thus, the secondary steam of the stage is introduced into the secondary heating chamber for reuse 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 drying device of the utility model realizes the agitation conveying mechanism of the directional heat exchange stroke of the sludge. According to the demand of the sludge treatment amount, the multi-axis combined rotation of the motor can be realized to realize the directional heat exchange stroke of the sludge, and the combined arrangement of the agitation conveying mechanism It is like pulling the meshing gear sets apart by an appropriate distance so that the mechanisms do not touch each other and the agitating surfaces have a certain superposition. The drying apparatus of the present invention can be set to a horizontal or different number of stages depending on the nature of the sludge, the moisture content of the dried product, the form of the dried product, the supply conditions of the external heating source, and the arrangement of the field.

Compared with the existing sludge drying device, the shaft type agitated sludge multi-stage secondary steam reuse drying device of the utility model has the advantages of:

(1) The shaft 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 mixing 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 risk of spontaneous combustion and explosion of dust. 08000160 After heating, 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 is dried and the external heating source consumes very little energy, and the energy saving effect is very remarkable.

(6) The granulation is not required before the sludge enters the drying device, 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 shaft-type agitated sludge multi-stage secondary steam reuse drying device, comprising a tubular body, characterized in that a feeding mechanism is arranged at the top of the body, and a hopper is arranged on the feeding mechanism; the bottom of the body is shrunk into a silo, the material The bottom of the silo is provided with a discharging mechanism; the stirring shaft is arranged along the shaft center, and the stirring shaft is coupled with the motor; the multi-layer hollow tray is arranged in the body, and the edge of the hollow tray is matched with the inner wall and fixedly connected. The space above the layer hollow tray is a sludge evaporation chamber; the hollow tray serves as a sludge heating chamber including 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 flow plate is spiral or labyrinth, and the heating plate, the partition plate and the baffle are enclosed to form a spiral or labyrinth heat source medium flow channel; the starting end of the heat source medium flow channel in the bottom hollow plate is through the pipeline The heat source is connected, 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 chamber below it pass through the tube Connected; the multi-layer hollow trays are arranged with a central discharge opening and a rim discharge opening, the central discharge opening is arranged at the center of the hollow tray, and the edge discharge opening is arranged at the edge of the hollow tray; each layer of hollow tower A stirring arm is arranged on the upper part, and the stirring arm is fixedly connected with the stirring shaft.

2. The shaft 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 shaft type agitating sludge multi-stage secondary steam recycling 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 shaft-type agitated sludge multi-stage secondary steam reuse drying device 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.

The shaft-type agitated sludge multi-stage secondary steam reuse drying device according to claim 1, wherein the silo is provided with a scraper arm, and the scraper arm is fixedly connected with the stirring shaft, and The position of the side wall of the silo corresponds.

6. The shaft-type agitated sludge multi-stage secondary steam reuse drying device according to claim 1, wherein the stirring arm is a tweezers, wherein the tweezers above the hollow tray provided with the central discharge port are provided. The dowel is inclined toward the center, and the dowel of the tweezers above the hollow tray provided with the edge discharge port is inclined toward the edge.

7. The shaft-type agitated sludge multi-stage secondary steam reuse drying apparatus according to claim 1, wherein the stirring arm is a scraper, wherein a scraper above the hollow tray provided with a central discharge port is provided. At the inner bend of the blade, the blade of the blade above the hollow tray provided with the edge discharge opening is at the outer bend.