WO2021051822A1

WO2021051822A1 - Modular industrial exhaust purification system and method for setting number of branch pipes

Info

Publication number: WO2021051822A1
Application number: PCT/CN2020/088132
Authority: WO
Inventors: 丁涛; 赵佳峰; 徐兆军; 朱南峰; 陈秀兰; 孙香
Original assignee: 南京林业大学
Priority date: 2019-09-18
Filing date: 2020-04-30
Publication date: 2021-03-25
Also published as: CN110711755A; CN110711755B

Abstract

A modular industrial exhaust purification system, comprising: several branch pipes, the branch pipes leading to waste gas emission source devices, and there being several waste gas emission source devices; a purification unit (5) connected to the branch pipes and a fan (6), the purification unit (5) being used for purifying waste gas delivered into the purification unit by the branch pipes, and the fan (6) being used for providing power for gas flow; and a discharge bin, used for collecting a waste material deposited by the purification unit. The system adopts a modular design, and each module comprises a suction hood, a suction pipe, a fan (6), and a gas purification unit (5). The modules can work independently to treat a part of emission source gas in a workplace, and can also be combined to form a combined system.

Description

Modular industrial exhaust purification system and method for setting number of branch pipes

Technical field

The invention relates to a purification system, in particular to a modular industrial exhaust purification system and a method for setting the number of branch pipes.

Background technique

Most industrial production processes are accompanied by various forms of exhaust gas emissions. The emissions mainly include dust and harmful gases. If they are not effectively treated, they will have an adverse impact on personnel health, process equipment, production safety, and product quality.

Equipping the production line with an industrial exhaust purification system is the mainstream method for processing production exhaust. The system is a local exhaust system in the workshop (Figure 1 and Figure 2). Exhaust branch pipes are installed in each emission source equipment to perform exhaust gas treatment. Suction, the polluted airflow from each branch pipe is collected to the main pipe 4 through the airflow branch pipes (the first branch pipe 1, the first branch pipe 2 and the third branch pipe 3 in the figure), and finally enters the exhaust purification device, which is exhausted by the purification device 5. The harmful substances in the air are separated from the air, and the purified air is discharged back to the atmosphere, and the harmful substances are effectively collected and centrally processed. In order to meet the power requirements of the system operation, the system needs to be equipped with a fan 6 to provide the energy required for the absorption of harmful gases, the flow of pipeline gas and the passage of the purification device. The power of the fan is calculated based on the discharge load of the workshop. The greater the exhaust gas emissions of the workshop, the higher the power required by the fan.

To ensure the normal operation of the traditional exhaust purification system, two key factors need to be considered when designing the system: First, the air volume of each airflow branch pipe should be greater than or equal to the basic air volume value required to effectively absorb the exhaust from the pollution source. The air volume value is mainly It depends on the exhaust characteristics of the pollution source, such as the work load of the equipment and the physical and chemical characteristics of the exhaust; the second is that the design airflow parameters of the branch pipes need to ensure that the pressure loss (resistance) of each parallel branch pipe is equal, that is, the so-called "pressure balance of the parallel pipeline" ", otherwise, each branch pipe will automatically adjust the airflow speed in the pipe during the actual work process until the pressure loss of each parallel branch pipe reaches the same value. At this time, the actual airflow parameters in the pipe will significantly deviate from the design value. In actual engineering cases, there is often a situation where the wind pressure of one branch pipe under the basic air volume is much greater than the wind pressure of the other branch pipe under its basic air volume. In the calculation of "pressure balance", it is necessary to increase the pressure of the branch pipe with a small wind pressure. The pressure loss is balanced with the branch pipe with high wind pressure. At this time, the selected air volume of the branch pipe will be significantly higher than the basic air volume that meets the effective absorption, resulting in an increase in the actual air volume of the system and an increase in energy consumption.

In actual operation, the traditional exhaust purification system also faces two problems. One is that only part of the production equipment in the workshop may be in operation. At this time, the air volume required for work is less than the rated air volume of the system, resulting in system energy consumption greater than actual needs. In response to this problem, frequency conversion technology is currently used so that the air volume of the fan can be adjusted according to the actual needs of the workshop, but this method has some shortcomings. First of all, for a given fan, although theoretically the air volume can be adjusted continuously, in fact, when the air volume deviates too much from the rated air volume, it will cause a significant drop in the efficiency of the fan and reduce the effective energy output of the fan. Secondly, after the air volume of the fan is reduced, the system only matches the total air volume with the required air volume of the workshop. However, in some parts of the pipeline, the actual air volume may be less than the minimum rated air volume, causing some particles in the airflow to settle at the bottom of the pipeline. After long-term accumulation Block the pipeline, or cause safety hazards. The second problem with traditional exhaust purification systems is that these systems are often equipped with a single purification device and fan. Once the purification device and fan fail, the entire system can only stop running, and the system has low fault tolerance.

Summary of the invention

In order to solve the above-mentioned problems, the present invention proposes a modular industrial exhaust purification system, which greatly simplifies the "balance calculation" of parallel pipelines in the design process by arranging modular purification device units and distributed power systems. The main consideration is the basic air volume required by each suction branch, which saves the total air volume required by the system and has energy-saving advantages.

The technical solution adopted by the present invention is: a modular industrial exhaust gas purification system, including a number of branch pipes, the branch pipes leading to exhaust gas emission source equipment, the exhaust gas emission source equipment has several; a purification unit connected to the branch pipe and A fan, the purification unit is used to purify the exhaust gas that the branch pipe is transported into the purification unit, and the fan is used to provide power for gas flow;

The discharge bin is used to collect the waste precipitated by the purification unit;

The method for setting the number of branch pipes connected to each exhaust emission source equipment is:

Calculate the total air volume required for the exhaust of several exhaust gas emission source equipment, and obtain the average air volume allocated to each purification unit according to the total air volume and the number of the purification units, and record it as the "reference air volume", according to each exhaust source The basic exhaust air volume of the equipment and the "reference air volume" obtain the number of branch pipes required by each exhaust emission source equipment.

Further, the branch pipe includes a branch pipe and a general branch pipe, the branch pipe is connected to the purification unit through the general branch pipe, and each general branch pipe corresponds to a purification unit and a fan.

Further, the method for setting the number of branch pipes corresponding to each exhaust emission source device is specifically as follows:

1) If the difference between the basic air volume required for the exhaust gas emission source equipment to effectively absorb and the "reference air volume" is less than a%, a separate branch pipe shall be provided for the exhaust emission source equipment;

2) If the basic air volume required for the exhaust gas emission source equipment to effectively absorb is higher than the "reference air volume", and the difference is greater than b%, then n branch pipes are used to jointly treat the exhaust emission source equipment, and the calculation scheme for n is as formula 1:

Where: n-the number of branch pipes connected to the exhaust emission source equipment;

Q _base -reference air volume;

Q _i -the basic air volume required by the exhaust emission source equipment;

3) If the basic air volume required for the exhaust gas emission source equipment to effectively absorb is higher than the "reference air volume", and the difference is between a% and b%, then one branch pipe will be used to process part of the air volume, and the remaining air volume will be compared with other exhaust gas emission source equipment After merging the branch pipes, connect to the purification unit;

4) If the basic air volume required for the exhaust gas emission source equipment to effectively absorb is less than the "reference air volume" and the difference is greater than a%, a branch pipe is set and the branch pipe is combined with the branch pipes of other exhaust gas emission source equipment to connect to the purification unit.

Further, the a% is 20% of the "reference air volume", and b% is 80% of the "reference air volume".

Further, the power of the fan of the purification unit does not exceed 10 kW.

Further, the a% is 10% of the "reference air volume", and b% is 90% of the "reference air volume".

The present invention also provides a method for setting the number of branch pipes connected to exhaust gas emission source equipment. The method is to calculate the total air volume required for the exhaust of several exhaust gas emission source equipment, and to obtain an even distribution to each unit according to the total air volume and the number of purification units. The air volume of each purification unit is recorded as the "reference air volume", and the number of branch pipes required by each exhaust emission source equipment is obtained according to the basic exhaust air volume and the "reference air volume" of each exhaust emission source equipment.

The beneficial effects produced by the present invention include: the scheme adopts a modular design, and each module includes an air suction hood, an air suction pipe, a fan, and a gas purification unit. Each module can work independently to process part of the emission source gas in the workplace, or can be combined together to form a combined system. The design of each branch pipe breaks the traditional method of setting up each sewage unit as a unit, and proposes a method of design and layout according to the set "reference air volume", so that the specifications of each purification unit and power module are unified, which greatly simplifies the system. Design to reduce manufacturing, installation and operating costs. During operation, the system can turn off or turn on the corresponding power and purification unit according to the actual production conditions, without the use of frequency converters, and the adjustment of the operating conditions will not affect the work of other parts of the system, which has the advantages of simplicity and flexibility. When a certain purification or power unit in the system fails, only the unit needs to be diagnosed and repaired, and the rest can maintain normal operation. The system has strong toughness and good fault tolerance.

Description of the drawings

Figure 1 Schematic diagram of traditional industrial exhaust purification system;

Figure 2 Layout of the traditional exhaust system;

Figure 3 is a schematic diagram of the industrial exhaust purification system proposed by the present invention;

Figure 4 Schematic diagram of the layout of the purification unit placed on one side of the system;

Figure 5 Schematic diagram of the layout of the purification unit placed on the top of the workshop.

detailed description

The present invention will be further explained in detail below with reference to the drawings and specific embodiments, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

The "reference air volume" is set according to the following principles: first determine the basic exhaust air volume requirements required by each exhaust emission source equipment, and then add the total air volume requirements of the system; then determine the required purification based on factors such as total air volume and workshop process characteristics The number of units 5, a general principle for determining the number is that the air volume processed by each purification unit 5 is limited to a small level, so that the air volume power it is equipped with is also low, in principle, it does not exceed 10kW, so that it can be guaranteed The operating parameters of the system in each purification unit 5 will not fluctuate greatly, and basically remain in a stable state. The branch pipes include a main branch pipe 8 and branch pipes. The main branch pipe 8 is connected to the purification unit 5, and the branch pipe and the remaining branch pipes are merged into the main branch pipe 8 and then connected to the purification unit 5. As shown in Figure 3, the plan I set 8 purification units 5; divide the total air volume by the number of purification units 5 to get the "reference air volume" of the branch pipe 8, and set the exhaust branch pipe 8 according to this air volume (in plan I There are 8 main branches in the middle 8). Schemes II, III, IV, V, and VI are equipped with different arrangements and different numbers of exhaust emission equipment.

The spatial layout of the main branch pipe 8 shall be carried out according to the following principles:

1) If the absolute value of the difference between the basic air volume required for effective absorption of an exhaust gas source and the "reference air volume" is less than 20% of the "reference air volume", a separate exhaust manifold 8 is provided for the source. According to the requirements of different systems, the difference threshold can be adjusted. For example, systems with higher precision requirements can set this difference to 10%.

2) If the basic air volume required for effective absorption of an emission source is more than 80% higher than the "reference air volume", n total branch pipes 8 are used to jointly treat the emission source. According to the requirements of different systems, the difference threshold can be adjusted, such as For systems that require higher accuracy, this difference can be set to 90%. n The calculation scheme is as formula 1:

In the formula: n-the number of total branch pipes 8; a=20 in this formula, it can be adjusted to 10 in a system with higher accuracy requirements.

Q _base -reference air volume;

Q _i -the basic air volume required by the emission source i.

3) If the basic air volume required for an emission source to effectively absorb is 120% to 180% of the "reference air volume", then one discharge main branch 8 will be used to treat 80% to 120% of the reference air volume, and the remaining air volume will be with adjacent waste gas. The basic air volume required by the emission source is considered together, and the number of exhaust manifolds required by the adjacent emission source is determined according to the principle shown in Formula 1.

4) If the basic air volume required for effective absorption of a certain exhaust gas emission source is less than 80% of the “reference air volume”, it shall be considered together with the adjacent exhaust gas emission source, and the branch pipe of the exhaust gas emission source shall be regarded as the branch pipe 8-1 and adjacent exhaust gas A certain branch pipe 8-2 of the emission source is merged into a branch pipe 8 connected to the purification unit 5 (Figure 4, Figure 5), and the number of exhaust branch pipes required by the adjacent emission source is determined according to the principle shown in Formula 1.

2 Each main branch 8 of the system corresponds to a purification unit 5 and a fan 6. The pipeline is directly connected to the purification unit 5, eliminating the main pipeline of the traditional system. Each purification unit 5 shares the same discharge bin 7, and the fan 6 through a locker. Set at the outlet of the purification unit 5, since the intake volume of each branch pipe 8 is basically the same, the specifications or models of the corresponding purification unit 5 and the fan 6 are also basically the same, which greatly reduces the types of components in the system. The application of the distributed power system makes the control method of the system very different from the traditional system: each branch pipe 8 only needs to select the fan 6 and the purification unit 5 to turn on or off according to the working conditions, with "0" and "1" The simple logic replaces frequency conversion adjustment, which has the advantages of simplicity and reliability. Another advantage of the modular design is that the working status of each branch pipe 8 has no effect on other pipelines of the system, and can be independently adjusted, and can be independently maintained when the processing unit has problems.

The shape, structure and layout of the purification unit 5 can be flexibly adjusted according to the working principle and workshop process. As shown in Figure 3, 6 structures and layout schemes from I to VI are given. As shown in Fig. 3, the different shapes are given to illustrate that the purification unit 5 can adopt different forms and combinations, which can be adjusted flexibly according to the needs of the application. This significantly increases the adaptability of the solution to different purification principles and process conditions, and can be applied to the technical requirements of various types of exhaust gas purification.

Example:

There are 3 exhaust emission source equipment a, b, and c in the workshop, which produce dust emissions during the production process. The dust types are the same. The arrangement of the 3 equipment in the workshop is shown in Figure 4, and the basic air volume requirements for exhaust are shown in Table 1. Shown:

Table 1 Basic exhaust volume requirements of equipment

废气排放源设备编号Exhaust emission source equipment number	基本排风量m ³/h Basic exhaust air volume m ³ /h
aa	30003000
bb	50005000
cc	1000010000

In the traditional design scheme, the first branch pipe 1, the second branch pipe 2 and the third branch pipe 3 are set at the exhaust emission source equipment a, the exhaust emission source equipment b and the exhaust emission source equipment c respectively (Figure 1 and Figure 2), and then After being collected to the main pipe 4, the purification unit 5 is connected. After the balance calculation, the total air volume required by the system is 20130m ³ /h, the total air pressure is 3948Pa, and the power of the fan 6 is selected as 37kW.

According to the design idea of the present invention, the basic air volume of 3 exhaust emission source equipment is firstly added to obtain a total air volume of 18000m ³ /h. Taking the number of total branch pipes 8 n=4, the reference air volume of each branch pipe 8 is 4500m ³ /h. The basic air volume requirement of equipment a is 3000m ³ /h, which is less than 80% of the reference air volume, so it is considered together with the adjacent equipment b. The basic air volume requirement of equipment b is 5000m ³ /h, and the basic air volume of equipment a is 8000m ³ /h. Two main branch pipes 8 can be used for processing. Each branch pipe 8 handles air volume of 4000m ³ /h. The difference in reference air volume is less than 20%. One of the main branch pipes is connected to equipment b, and the processing air volume is 4000m ³ /h. The remaining 1000m ³ /h required by equipment b and the air volume required by equipment a 3000m ³ /h respectively pass through the second branch pipe 8-2 and the first branch The pipe 8-1 is merged into a branch pipe 8 for processing. Since the air volume of the two devices needs to be merged, the branch pipe 8 is a Y-shaped pipe, and the actual air volume after the balance calculation is 4050m ³ /h. The basic air volume required by equipment c is more than 80% higher than the reference air volume, so two main branch pipes 8 are used for processing, and each branch pipe 8 processes 5000 m ³ /h, and the difference with the reference air volume is less than 20%. This procedure can, standard air volume purification unit of each total branched tube 8 with 5 are 4500m ³ / h, the standard total air volume 18000m ³ / h, the actual air volume 18050m ³ / h, 10% lower than the conventional scheme; units The power of the equipped fan 6 is 7.5kW, and the total installed capacity of the system is 30kW, which is 18% lower than the traditional scheme. The total air volume obtained by this system based on the addition of the basic air volume of each device is 18000m ³ /h, which is the source of the standard total air volume. In the actual calculation, since there is a main branch pipe 8 connecting two branch pipes, namely the first branch pipe 8-1 and the second branch pipe 8-2, the balance calculation is performed to make the actual air volume reach 4050m ³ /h, The set air volume exceeds 4000m ³ /h, so the final actual total air volume reaches 18050m ³ /h.

The system space layout can be flexibly adjusted according to the actual needs of the workshop process. The purification unit 5 can be placed on the side of the system (Figure 4) or on the top of the workshop (Figure 5).

The foregoing are only preferred embodiments of the present invention, and the present invention is not limited to the content of the embodiments. For those skilled in the art, various changes and modifications are possible within the scope of the technical solution of the present invention, and any changes and modifications made are within the protection scope of the present invention.

Claims

A modular industrial exhaust purification system, which is characterized in that it includes

Several branch pipes, the branch pipes leading to exhaust gas emission source equipment, and the exhaust gas emission source equipment has several;

A purification unit and a fan connected to the branch pipe, where the purification unit is used to purify the exhaust gas delivered by the branch pipe into the purification unit, and the fan is used to provide power for gas flow;

The discharge bin is used to collect the waste precipitated by the purification unit;

The method for setting the number of branch pipes connected to each exhaust emission source equipment is:

Calculate the total air volume required for the exhaust of several exhaust gas emission source equipment according to the basic exhaust air volume required for the exhaust purification of each exhaust gas emission source equipment, and obtain an even distribution to each unit according to the total air volume and the number of purification units. The air volume of the purification unit is recorded as the "reference air volume", and the number of branch pipes required by each exhaust emission source equipment is obtained according to the relationship between the basic exhaust air volume of each exhaust emission source device and the "reference air volume".
The modular industrial exhaust purification system according to claim 1, wherein the branch pipe includes a branch pipe and a main branch pipe, and the branch pipe is connected to the purification unit through the main branch pipe, and each of the main branch pipes is connected to the purification unit. Corresponding to a purification unit and fan.
The modular industrial exhaust purification system according to claim 1, wherein the method for setting the number of connected branch pipes corresponding to each exhaust emission source device is specifically as follows:

1) If the difference between the basic air volume required for the exhaust gas emission source equipment to effectively absorb and the "reference air volume" is less than a%, a separate branch pipe shall be provided for the exhaust gas emission source equipment;

2) If the basic air volume required for the exhaust gas emission source equipment to effectively absorb is higher than the "reference air volume", and the difference is greater than b%, then n branch pipes are used to jointly treat the exhaust emission source equipment, and the n calculation scheme is as formula 1:

Where: n-the number of branch pipes connected to the exhaust gas emission source equipment;

Q base -reference air volume;

Q i -the basic air volume required by the exhaust emission source equipment;

3) If the basic air volume required for the exhaust gas emission source equipment to effectively absorb is higher than the "reference air volume", and the difference is between a% and b%, then one branch pipe will be used to process part of the air volume, and the remaining air volume will be the same as the rest of the exhaust gas emission source. The branch pipes of the equipment are merged into the main branch pipe and then connected to the purification unit;

4) If the basic air volume required for the exhaust gas emission source equipment to effectively absorb is less than the "reference air volume" and the difference is greater than a%, then a branch pipe is set and the branch pipe and the branch pipes of the other exhaust gas emission source equipment are merged into the main branch pipe Then connect the purification unit.
The modular industrial exhaust purification system according to claim 3, wherein the a% is 20% of the "reference air volume", and b% is 80% of the "reference air volume".
The modular industrial exhaust purification system according to claim 1, wherein the fan power of the purification unit does not exceed 10 kW.
The modular industrial exhaust gas purification system according to claim 3, wherein the a% is 10% of the "reference air volume", and b% is 90% of the "reference air volume".
A method for setting the number of branch pipes connected to exhaust gas emission source equipment is characterized in that the total air volume required for the exhaust of several exhaust gas emission source equipment is calculated, and the total air volume and the number of purification units are evenly distributed to each purification unit. The air volume of the unit is recorded as the "reference air volume", and the number of branch pipes required by each exhaust emission source equipment is obtained according to the relationship between the basic exhaust volume of each exhaust emission source device and the "reference air volume".