CN104930502B - A kind of multi-channel distribution device for being applicable the material balance control of many bed body systems - Google Patents

Abstract

The invention discloses a multi-channel distributing device suitable for controlling the balance of circulating materials in a multi-bed system. It communicates with the material inlet of the material distribution core area, and the discharge channel communicates with the material discharge port of the material distribution core area, and each discharge channel is provided with a gate valve; the air chamber system is provided with a plurality of air The chambers correspond to the material distribution core area and each discharge channel respectively. The present invention mainly utilizes the circulation and transmission characteristics of the bubbling bed and the closed pressure control principle of the moving bed, and forms a distribution device that realizes precise control of material circulation in a multi-bed system through single-channel control of feed and combined with multi-channel discharge.

Description

A multi-channel distribution device suitable for multi-bed system circulation material balance control

technical field

The invention relates to a multi-channel distributing device applicable to the balance control of circulating materials in a multi-bed system, which is used for improving the utilization efficiency of low-quality and inferior fuels.

Background technique

With the development of circulating fluidized bed in the field of thermal conversion of coal and biomass, a double-bed, three-bed, four-bed and other multi-bed circulation systems with circulating materials as energy circulation carriers have gradually been formed. And it has already appeared in typical applications in the fields of coal gasification and biomass combustion. In this process, the distribution and control of circulating materials, especially high-temperature circulating materials in double-bed, three-bed and other multi-bed systems is an important link in this process. For example, in a dual-bed system, the temperature of one of the beds is directly controlled by the circulating material during the high-rate cycle. How to control the bed temperature of the auxiliary bed is the key to the stable operation of the dual-bed system. The main function of the distribution device is to meet the needs of particle circulation on the one hand, and on the other hand to meet the needs of preventing gas backchanneling and stabilizing the pressure flow field of the system. This process requires that the dispensing device has both flow-through and sealing properties. The return valve plays a similar role in the circulating fluidized bed system, but this device is only limited to the function of circulating materials and does not have the function of distributing materials. There are also patents introducing a distribution valve with dual channels. Chinese invention patent 200510102904.6 discloses a distribution valve with a distribution function. The dual-channel distribution function of materials is realized by setting a numerical splitter plate, but a splitter plate is set at the bottom, which is equivalent to distributing the bottom of the valve. The partition blocks the fluidity between the particles, which is easy to cause bias flow and channel flow. At the same time, the functional partition of the air chamber is not perfect, and it is impossible to achieve matching decentralized control, which increases the difficulty of on-site control. The actual application effect is not ideal, the main reason is that the distribution valve combined with the mechanism of moving bed and bubbling bed is more troublesome to operate and the operating space is narrower.

Contents of the invention

Purpose of the invention: According to the development frontier of circulating fluidized beds at home and abroad and the material balance requirements of multi-bed systems, the present invention provides a multi-channel distribution device suitable for the control of circulating material balance in multi-bed systems, which is used to solve the problems in the existing multi-bed circulation systems. The distributing device is easy to cause bias flow and channel flow, and the function of the air chamber is not perfect, the field control is difficult, and the operation is cumbersome and other technical problems.

Technical scheme: in order to achieve the above object, the technical scheme adopted in the present invention is:

A multi-channel distribution device suitable for multi-bed system circulation material balance control, including a feed channel, a material distribution core area and a discharge channel; there is an air chamber system at the bottom of the entire device; the feed channel and the material distribution core The feed port of the area is connected, the discharge channel is connected with the discharge port of the material distribution core area, and each discharge channel is provided with a gate valve; the air chamber system is provided with a plurality of air chambers respectively connected to the material Allocation of the core area and corresponding to each discharge channel.

The above-mentioned device is applied to the material circulation and distribution of the multi-bed circulation system. Although different multi-bed circulation systems have different combinations, as long as the feed channel of the device is installed in the gas-solid separation device in the multi-bed circulation system Material outlet, here the solid material outlet of the gas-solid separation device can be one or more, that is, the feed channel is not limited to a single material inlet, it is only required to form a single outlet before entering the device, in addition, the device needs to be The discharge channel in the multi-bed circulation system is connected to each moving bed, and the setting of the specific communication channel and the selection of the communication method can be determined according to the process requirements. The material flows into the material distribution core area through the feed channel, and through the action of the air chamber system, the fluidized air is introduced to make the solid material present a fluidized bubbling state. Here, the material distribution core area and the air chamber system as a whole can be realized by a bubbling bed , by controlling the air chamber system, the material flows in the corresponding discharge channel and enters the multi-bed circulation system to form and maintain a stable working state.

Therefore, the present invention meets the pressure closure requirements of the multi-bed circulation system by forming a material seal through the moving bed, and at the same time combines the bubbling bed to convert the static pressure into flow power to realize the distribution function of different levels of materials, and utilizes the above two beds to control particle movement. Different from the typical ones above, a multi-channel complex multi-system flow distribution device is formed in which the moving bed controls the material channel and the bubbling bed controls the material flow guide. At the same time, combined with the side wall flow and the flow of the main fluid and the speed difference, through the multi-chamber air chamber and partition air chamber, the wind speed of different air chambers can be adjusted according to the needs, and the flow characteristics of different fluids can be precisely controlled to achieve different functional areas. Different fluidization states are used to control the balance control of materials, and an optimal control strategy can be formed by setting a feedback device. Further, an ash unloading port is set inside the distribution device to realize the controllable amount of circulating ash.

Further, in the present invention, it also includes an ash unloading pipe and a slag cooler, one end of the ash unloading pipe is connected to the ash unloading port of the material distribution core area, and the ash unloading port is located at the geometric center of the bottom of the material distribution core area At the place, the other end of the ash discharge pipe is connected to the slag cooler. The diameter of the ash discharge port is set to be smaller than the feed channel

Further, in the present invention, the air chamber system includes a core air chamber and a plurality of discharge channel side wall air chambers; the core air chamber includes a central air chamber and a peripheral air chamber, wherein the central air chamber is aligned with the material distribution core In the central area of the area, the peripheral air chamber is located around the central air chamber and corresponds to each discharge channel; the side wall air chamber of the discharge channel corresponds to the discharge channel, and is aligned with the side wall of the discharge channel.

Further, in the present invention, the vertical height of the feed channel from the inlet position to the outlet position connected to the material distribution core area is set to be 3 to 5 times the pressure drop of the multi-bed circulation system.

Further, in the present invention, the discharge channels can be arranged in pairs or not. For example, if it is set up in pairs of two channels, four channels, six channels, etc., since the material is evenly distributed when it falls from the feed channel into the core area of material distribution, it can be set in pairs to maximize the uniformity. The distributed material is discharged from the discharge channel of each work. At the same time, considering the purpose of emergency discharge of circulating materials, the channels are paired to facilitate the control of furnace stability and the need for emergency large-scale slag discharge. When the discharge passages appear in pairs, the paired passages balance and control the inhomogeneity of the material outflow velocity, and an angle is set between the discharge passages, wherein the projection of the angle between the discharge passages in the vertical plane Control it at 15°～30°. It can also be arranged in pairs according to actual needs, such as odd-numbered channels such as single channel, three channels, and five channels, and the projection of the included angle between each channel in the vertical plane is also set to 15°～30°, and then Change the flow state between each discharge channel from symmetrical distribution to asymmetrical distribution to achieve the effect of asymmetrical material distribution. Furthermore, in the present invention, the shape of the inlet of the material feeding channel of the device can be square, polygonal, elliptical, circular, etc., but preferably circular, which is conducive to smooth flow of materials.

Further, in the present invention, the feed channel and the discharge channel are replaceable pipes, and pipes of different lengths can be replaced and selected according to the process arrangement, and the selected material is high-temperature-resistant and wear-resistant stainless steel. This facilitates the joint control of material seal height and flow section adjustment.

Furthermore, in the present invention, the discharge channels can be arranged on the same plane, or they can be arranged on different planes in a staggered arrangement; and the cross section of the discharge channel is not smaller than the cross section of the feed channel.

Beneficial effect:

The multi-channel distributing device of the present invention, which is applicable to the balance control of circulating materials in a multi-bed system, mainly utilizes the circulation transfer characteristics of the bubbling bed and the closed pressure control principle of the moving bed, and controls the feeding through a single channel and combines the multi-channel output. In the form of a multi-bed system, it forms a distribution device that can precisely control the material circulation of the multi-bed system, which has the following advantages:

1. It has wide adaptability and can be adapted to various systems that require material distribution.

2. The material seal is controllable, and the amount of returned material is controllable. Import pipes of different heights can be used to realize the controllable height of the material seal, and the multi-bed circulation system can meet the requirements of different pressure differences. By controlling the ash discharge amount of the ash discharge port, it can be realized The amount of returned material is controlled and the amount of solid material circulated throughout the multi-bed circulation system.

3. Partitioned fluidization, according to different air chamber functions, control the pressure and flow of different air chambers to control the fluidization effect of the corresponding area to achieve partitioned fluidization, and solve the problem of feeding pipelines, returning pipelines, central areas, side wall areas, unloading areas, etc. Difficulties caused by different requirements for fluidization intensity in the slag area, the intersection of the moving bed and the bubbling bed area, etc.

4. Multi-channel collaborative distribution of materials, by setting different channels and the unique structure of the material distribution core area to achieve simultaneous collaborative distribution of multi-channel materials, realize the synergistic effect on the function of the multi-bed system, and maximize the realization of the multi-bed circulation system for material distribution. need.

Description of drawings

Fig. 1 represents the schematic diagram of a four-channel distribution device of a four-bed system circulation material balance control;

Figure 2 shows an explanatory diagram of the two-channel bottom air chamber;

Figure 3 represents a partial view of the left discharge channel;

Figure 4 shows a top view of the four-channel distribution valve;

Figure 5 shows a top view of the three-channel distribution valve;

Figure 6 shows an application example of a three-channel distribution valve suitable for a three-bed system.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, a multi-channel distribution device applicable to the balance control of the multi-bed system circulation material is used for the material circulation and distribution of the multi-bed circulation system, including a feed channel 1, a material distribution core area 7 and a discharge channel; There is an air chamber system at the bottom of the whole device; the feed channel 1 is communicated with the feed port of the material distribution core area 7, and the discharge channel is communicated with the discharge port of the material distribution core area 7, and each outlet Gate valves are arranged on the material passages; multiple air chambers are provided in the air chamber system corresponding to the material distribution core area 7 and each discharge passage respectively. It also includes an ash discharge pipe 19 and a slag cooler 20, one end of the ash discharge pipe 19 is connected to the ash discharge port of the material distribution core area 7, and the ash discharge port is located at the geometric center of the bottom of the material distribution core area 7. The other end of the ash pipe 19 is connected to a slag cooler 20 .

The air chamber system includes a core air chamber and a plurality of discharge channel air chambers, wherein the core air chamber is aligned with the material distribution core area 7, and one discharge channel air chamber corresponds to one discharge channel; the core air chamber and the discharge channel The air chambers of the material channel all include a middle air chamber and a side wall air chamber, wherein the side wall air chambers are distributed on both sides of the middle air chamber, and the middle air chamber of the core air chamber is aligned with the center of the material distribution core area 7, and the core air chamber The side wall air chamber of the chamber is aligned with the side wall of the material distribution core area 7, the middle air chamber of the discharge channel air chamber is aligned with the center of the corresponding discharge channel, and the side wall air chambers of the discharge channel air chamber are respectively aligned with the The side walls of the corresponding outlet channels are aligned.

Embodiment 1,

The bottom air chamber including the left and right two discharge channels as shown in Figure 3 is used to illustrate the automatic and precise control method for multiple air chambers. Air chambers 9, 12, 14, 15, 16 are core air chambers, and air chamber 15 therein is a central air chamber, and air chambers 9, 12, 14, 16 are peripheral air chambers of the central air chamber, and air chamber 14 , 16 respectively to a left discharge channel and a right discharge channel, the air chambers 14, 15, 16 are the main air supply areas for fluidization control, accounting for 70% of the total air volume, and the middle air chamber 15 is located at the ash discharge port 6 Nearby, and the air volume is greater than the other two air chambers, accounting for at least 60% of the air volume of the core air chamber. The air chambers 8, 11, 10, and 13 are the side wall air chambers of the discharge channel. As shown in Figure 3, the air chambers 8, 11 are aligned with the side walls of the left discharge channel. Correspondingly, the air chambers 10, 13 are paired For the position of the side wall of the right discharge channel, since the main function of the air chamber on the side wall of the discharge channel is to overcome the resistance of the side wall, the air volume of these four air chambers accounts for 30% of the total air volume. Flow control instruments are installed on the pipelines connected to all air chambers for adjustment. According to engineering experience and device load conditions, unattended control and intelligent operation of distribution valves can be realized by setting corresponding programs.

Example 2

A method of using a four-channel distribution valve suitable for a four-bed system, as shown in Figure 1-4, the four discharge channels are the left discharge channel 2, the right discharge channel 3, the front discharge channel 4 and the rear discharge channel. In the discharge channel 5, the granular material enters the feed channel 1 through the separation device. At this time, the ash discharge pipe 19 connected to the ash discharge port 6 should be closed to prevent the solid material from flowing out. When the high-temperature material enters the material distribution core area 7, the air chambers 9, 12, 14, 15, and 16 start to flow into the fluidizing air so that the solid material presents a fluidized bubbling state, and the temperature of the distribution valve begins to rise, and the rising speed is relatively slow. Can open the shut-off valve on the ash unloading pipe 19 now to make the cold ash flow out from the distributing valve. When the temperature of the material in the distribution valve rises rapidly or when the temperature reaches 700° C., close the stop valve on the ash discharge pipe 19 . Simultaneously open the left gate valve 18 on the left discharge channel 2, open the left air chambers 8, 11, and adjust the fluidization wind at about the fluidization multiple of 5-7. When opening all air chambers 8 and 11 on the left side, the relevant air chambers of the remaining discharge passages should be closed. When the left discharge channel 2 achieves stable operation, it indicates that the start-up and debugging process is over, and other discharge channels are opened in turn according to the production process requirements, and then the stable operation of multiple channels can be maintained.

Example 3

This embodiment is applicable to the application example of the three-channel distribution valve of the pyrolysis-drying-combustion three-bed system, as shown in Figure 5, including the left discharge channel 2, the right discharge channel 3 and the rear discharge channel 5, and the specific device connections As shown in FIG. 6 , feed channel 1 is connected to cyclone separator 24 , left discharge channel 2 is connected to main entrained flow bed 21 , right discharge channel 3 is connected to drying bed 23 , and rear discharge channel 5 is connected to pyrolysis bed 22 . The main entrained flow bed 21 is the main fluidized bed for solid particles to obtain heat and realize combustion or gasification, and entrained flow bed, conveying bed, etc. can be used. After the high-temperature solid passes through the cyclone separator 24, it enters the feed channel 1 of the distribution device. Adjust the bottom air chamber to realize that the material enters the drying bed 23, and the water-containing material is dried. The drying bed 23 communicates with the main air flow bed 21 and the pyrolysis bed 22, and the dry material coming out of the drying bed 23 can enter the main air flow bed 21 for combustion or Gasification can also enter the pyrolysis bed 22 for pyrolysis and gasification. According to the process requirements, in this embodiment, the material enters the pyrolysis bed 22 for pyrolysis to generate gas. After the dry material enters the pyrolysis bed 22, it is mixed with the high-temperature solid particles coming out of the rear discharge channel 5 to realize pyrolysis to form gas with low water content and high calorific value. The remaining solid particles in the distribution device enter the main entrained flow bed 21 through the left discharge channel 2 to heat up again. When the particle circulation is insufficient, the solid carrier can be supplemented. When the three-bed system circulation is excessive, it can be carried out through the ash discharge port 6. Ash unloading to balance material distribution.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications are also possible. It should be regarded as the protection scope of the present invention.

Claims (4)

1. a kind of multi-channel distribution device for being applicable the material balance control of many bed body systems, the material for many circulating systems Circulation and distribution, it is characterised in that：Including feeding-passage (1), material distribution nucleus (7) and tapping channel；Entirely filling The bottom put carries plenum system；The charging aperture that the feeding-passage (1) and material distribute nucleus (7) is connected, it is described go out The discharging opening that material passage distributes nucleus (7) with material is connected, and is provided with gate valve on each tapping channel；The air compartment Multiple air compartments of core air compartment and multiple tapping channel side wall air compartments composition are provided with system, wherein core air compartment includes center Air compartment and periphery air compartment, multiple air compartments are corresponding with material distribution nucleus (7) and each tapping channel respectively, wherein center The central area of air compartment alignment material distribution nucleus (7), periphery air compartment is located at around the air compartment of center and each corresponding discharging Passage, tapping channel side wall air compartment is corresponding with tapping channel, and the sidewall locations of alignment tapping channel are set；And core air compartment Air quantity at least account for the 70% of total air compartment air quantity, the air quantity of center air compartment at least accounts for more than the 60% of core air compartment air quantity, side wall The air quantity of air compartment accounts for the 30% of total air compartment air quantity；Also include ash-unloading tube (19) and lag cooler (20), described ash-unloading tube (19) one end The cinder-discharging port of material distribution nucleus (7) is communicated to, the cinder-discharging port is located at the geometry that material distributes nucleus (7) bottom Center position, the other end of ash-unloading tube (19) is communicated to lag cooler (20).

Filled 2. being distributed according to any one in claim 1 multichannel for being applicable the material balance control of many bed body systems Put, it is characterised in that：The feeding-passage is from entry position to distributing the outlet port that nucleus (7) is connected with material Vertical height be set to 3~5 times of many circulating system pressure drops.

3. being applicable the multi-channel distribution device of many bed body systems material balance control according to claim 2, its feature exists In：Projection of the angle in perpendicular between each tapping channel is arranged to 15 °~30 °.

4. being applicable the multi-channel distribution device of many bed body systems material balance control according to claim 2, its feature exists In：The feeding-passage and tapping channel are replaceable, and the material selected is heat resistant and wear resistant stainless steel material.