CN111054174B

CN111054174B - Exhaust gas purifying device

Info

Publication number: CN111054174B
Application number: CN201811208966.9A
Authority: CN
Inventors: 王玉伟
Original assignee: Illinois Tool Works Inc
Current assignee: Illinois Tool Works Inc
Priority date: 2018-10-17
Filing date: 2018-10-17
Publication date: 2023-08-08
Anticipated expiration: 2038-10-17
Also published as: WO2020081222A1; TWI818081B; CN111054174A; TW202019549A

Abstract

The application discloses exhaust gas purification device for purify pollutant in the waste gas in the reflow oven furnace, include: the shell is provided with a cooling cavity; the first cooling device is arranged in the cooling cavity; wherein the first cooling device comprises a plurality of cooling fins arranged longitudinally and at least one cooling tube through which a gas flows to form a longitudinal gas flow, the cooling tube having a cavity for receiving a cooling medium. After the waste gas enters the first cooling device, the waste gas is subjected to heat exchange with the cooling pipes through the cooling fins, so that pollutants in the waste gas can be condensed into liquid to be separated.

Description

Exhaust gas purifying device

Technical Field

The present application relates to an exhaust gas treatment system for a reflow oven, and more particularly to an exhaust gas purifying apparatus for purifying exhaust gas in a furnace chamber of a reflow oven.

Background

In the fabrication of printed circuit boards, electronic components are typically mounted to the circuit board using a process known as "reflow soldering". In a typical reflow soldering process, solder paste (e.g., solder paste) is deposited onto selected areas of a circuit board and wires of one or more electronic components are inserted into the deposited solder paste. The circuit board then passes through a reflow oven in which the solder paste is reflowed (i.e., heated to a melting or reflow temperature) in a heated zone and then cooled in a cooled zone to electrically and mechanically connect the leads of the electronic component to the circuit board. The term "circuit board" as used herein includes substrate assemblies of any type of electronic component, including, for example, wafer substrates. In reflow ovens, air or a substantially inert gas (e.g., nitrogen) is typically used as the working gas, with different working gases being used for circuit boards of different process requirements. The hearth of the reflow oven is filled with a working gas in which the circuit board performs soldering while being conveyed through the hearth by the conveyor.

In a reflow oven, the solder paste includes not only solder, but also flux that promotes wetting of the solder and provides good solder joints. Other additives such as solvents and catalysts may also be included. After depositing solder paste on the circuit board, the circuit board is transported on a conveyor through a plurality of heated areas of a reflow oven. The heat in the heated area causes the solder paste to melt and volatile organic compounds (referred to as "VOCs"), including mainly the flux, to vaporize to form vapors, thereby forming "contaminants". The build up of these contaminants in the reflow oven can cause problems. For example, if contaminants reach the cooling area, they will condense on the circuit board and contaminate the circuit board, thereby necessitating a subsequent cleaning step. Contaminants can also condense on the surfaces of the coolers of the reflow oven, thereby blocking the air holes. In addition, condensation may also drip onto subsequent circuit boards, possibly damaging components on the circuit boards or necessitating subsequent cleaning steps of the contaminated circuit boards.

Disclosure of Invention

It is desirable to remove the waste gas containing contaminants from the reflow oven cavity from the cavity to keep the working atmosphere in the reflow oven cavity clean to prevent contaminants from entering the reflow oven cooling zone, which can cause problems in the reflow oven.

When the reflow oven is operated with a substantially inert gas (e.g., nitrogen), it is often desirable that the exhaust gas exiting the reflow oven be cleaned by an exhaust gas cleaning system and then transported back to the reflow oven for reuse because the substantially inert gas (e.g., nitrogen) is expensive. When the reflow oven takes air as working gas, the waste gas discharged from the reflow oven can be directly discharged into the atmosphere after being treated by the waste gas purifying system, and can be conveyed back to the reflow oven for recycling.

One treatment option is to cool the exhaust gas in a cooling device to below about 80 ℃ so that the contaminants in the exhaust gas are condensed from gaseous form to liquid or solid form and then the contaminants are removed in liquid or solid form. However, the contaminants in liquid or solid form formed by cooling are not only easy to adhere to the inner wall of the cooling device and difficult to clean, so that the maintenance period is short, the maintenance cost is high, but also adhere to the heat exchange components (such as the heat exchange plates or the heat exchange tubes) of the cooling device, and the heat exchange efficiency is affected.

On the other hand, in the exhaust gas purification system of the related art, the cleaning of the connection pipe and the devices of each part of the exhaust gas purification system requires manual cleaning, and is thus very inconvenient.

Through observation and research, the applicant found that the difficult-to-clean contaminants adhering to the inner wall of the cooling device and to the heat exchange member in the exhaust gas purification system were mainly rosin in solid form. This is because rosin and other flux in the contaminants solidify directly from a gaseous form to a solid form when cooled from a high temperature to about 80 c, adhere to the inner wall of the cooling device and the heat exchange member, and affect the heat exchange efficiency while making the maintenance period of the exhaust gas purification system too short.

In order to solve at least one of the problems described above, at least one object of the present application is to provide an exhaust gas purifying apparatus for purifying exhaust gas in a furnace hearth of a reflow oven, which can make rosin not easily adhere to an inner wall of a cooling device in the exhaust gas purifying apparatus, thereby prolonging a maintenance period, and at the same time, the exhaust gas purifying apparatus is also convenient for maintenance cleaning.

In order to achieve the above object, a first aspect of the present application provides an exhaust gas purifying apparatus for purifying exhaust gas in a reflow oven furnace hearth, the exhaust gas purifying apparatus comprising: the device comprises a shell, a cooling device and a cooling device, wherein an exhaust gas inlet is formed in the shell, the shell is provided with a top and a bottom, and the shell is provided with a cooling cavity; and a first cooling device, the cooling volume comprising a first cooling volume, the first cooling device being disposed within the first cooling volume, the exhaust gas inlet being in fluid communication with the first cooling volume; wherein the first cooling device comprises: a plurality of cooling fins arranged longitudinally, each of the plurality of cooling fins being disposed transversely and each of the plurality of cooling fins having a plurality of through slots therein such that gas can flow through the through slots to form a longitudinal gas flow, and the plurality of cooling fins being disposed with the through slots in at least a portion of adjacent two of the plurality of cooling fins being staggered; and at least one cooling tube, each of the at least one cooling tube having a cavity for receiving a cooling medium.

According to the first aspect, each layer of cooling fins is provided with a U shape, and the through groove is formed at the bottom of the cooling fin; the at least one cooling tube comprises a plurality of layers of cooling tubes, each layer of cooling tubes transversely passing through a side wall of one layer of cooling fins for supporting the cooling fins such that the cooling tubes are in heat exchange relationship with the longitudinal gas flow through the cooling fins.

According to the first aspect, the side wall of each layer of cooling fin is provided with a side groove, and the side groove is communicated with the through groove, so that the cooling fin can be detachably mounted on the cooling pipe through the side groove and the through groove.

According to the first aspect, the cooling cavity further comprises a second cooling cavity, and the second cooling cavity is communicated with the first cooling cavity; the exhaust gas purification device further comprises a second cooling device disposed within the second cooling plenum, wherein the second cooling device comprises at least two cooling plates arranged laterally, each of the at least two cooling plates having a cavity for receiving a cooling medium, wherein each of the at least two cooling plates is vertically disposed and spaced apart from an adjacent cooling plate to form a vertical gas channel; wherein at least a portion of the at least two cooling plates are arranged to: each of which forms a bottom transverse gas channel with the bottom of the housing or a top transverse gas channel with the top of the housing, and wherein the bottom transverse gas channels and the top transverse gas channels are alternately arranged in the arrangement direction of the at least two cooling plates; wherein the bottom transverse gas channel and the top transverse gas channel are in fluid communication with the vertical gas channel to form a curved gas cooling channel; the longitudinal gas flow is in fluid communication with the gas cooling passage.

According to the first aspect described above, the exhaust gas purifying device further includes a liquid collecting device connected to the bottom of the housing, the liquid collecting device being in fluid communication with the cooling chamber.

According to the first aspect, the shell is provided with a purified gas outlet; the housing has a filtration volume with a filter element therein, the filtration volume in fluid communication with the gas cooling channel; and the clean gas outlet is communicated with the filtering containing cavity so that gas can flow through the filtering component and be discharged from the clean gas outlet.

According to the first aspect described above, a connection channel is provided in the housing, the connection channel having a self-cleaning gas inlet and a self-cleaning gas outlet, wherein the self-cleaning gas outlet is in fluid communication with the filter volume, and the self-cleaning gas inlet is in fluid communication with the cooling volume.

According to the first aspect described above, the exhaust gas purifying apparatus further includes a shroud provided in the housing; wherein the connecting channel is formed by the shell and the coaming together.

According to the first aspect, the housing further has a rear portion, and the coaming includes a cross plate and a riser, the cross plate abutting against the rear portion of the housing, and the riser abutting against the top portion of the housing, so that the coaming and the housing together form the connection passage.

According to the first aspect, the exhaust gas purifying device further includes a partition plate disposed between the cooling chamber and the filtering chamber, for partitioning the cooling chamber and the filtering chamber; the partition plate is provided with an upper opening and a lower opening, the lower opening is positioned below the filtering component and used for communicating the cooling cavity with the filtering cavity, and the upper opening is positioned above the filtering component and used for communicating the filtering cavity with the connecting channel.

According to the first aspect, an adjustable baffle is arranged at the upper opening to open or close the upper opening or adjust the opening size of the upper opening.

According to the first aspect, at least one flow equalizing plate is arranged in the cavity of the at least two cooling plates, the flow equalizing plate is arranged on the flow path of the cooling medium, and a plurality of through holes are uniformly formed in the flow equalizing plate, so that the cooling medium can pass through the through holes in the flow process.

According to the first aspect, the exhaust gas purification device further comprises a fan connected to the filter volume, wherein the fan has an air inlet side in fluid communication with the filter volume and an air outlet side in fluid communication with the clean air outlet and the upper opening.

According to the first aspect, the filtering component is a steel ball filtering net.

According to the first aspect described above, the cooling medium contained in the cavity of the cooling pipe is compressed air, and the cooling medium contained in the cavity of the cooling plate is air.

The conception, specific structure, and technical effects of the present application will be further described with reference to the accompanying drawings to fully understand the objects, features, and effects of the present application.

Drawings

FIG. 1A is a simplified block diagram of an exhaust gas purification system according to one embodiment of the present application;

fig. 1B is a block diagram showing a gas flow path when the exhaust gas purification system in fig. 1A is in an operating state;

fig. 1C is a block diagram showing a gas flow path when the exhaust gas purification system in fig. 1A is in a maintenance state;

fig. 2A is a schematic perspective view of an exhaust gas purifying apparatus according to an embodiment of the present application;

fig. 2B is a front view of the exhaust gas purifying apparatus shown in fig. 2A;

fig. 2C is a plan view of the exhaust gas purifying apparatus shown in fig. 2A;

fig. 3 is an exploded construction view of the exhaust gas purifying apparatus shown in fig. 2A;

FIG. 4 is a cross-sectional view taken along line A-A of FIG. 2B;

FIG. 5 is a cross-sectional view taken along line B-B of FIG. 2C;

Fig. 6 is a schematic perspective view of a cooling device in the exhaust gas purifying device shown in fig. 2A;

fig. 7A is a schematic perspective view of an exhaust gas purifying apparatus according to another embodiment of the present application;

fig. 7B is a front view of the exhaust gas purifying apparatus shown in fig. 7A;

fig. 7C is a plan view of the exhaust gas purifying apparatus shown in fig. 7A;

fig. 8 is an exploded construction view of the exhaust gas purifying apparatus shown in fig. 7A;

FIG. 9 is a cross-sectional view taken along line A-A of FIG. 7B;

FIG. 10A is a cross-sectional view taken along line B-B of FIG. 7C;

FIG. 10B is a cross-sectional view taken along line C-C of FIG. 10A;

fig. 11 is a schematic perspective view of a cooling device in the exhaust gas purifying device shown in fig. 7A.

Detailed Description

Various embodiments of the present application are described below with reference to the accompanying drawings, which form a part hereof. It is to be understood that, although directional terms, such as "front", "rear", "upper", "lower", "left", "right", "top", "bottom", "side", etc., may be used in this application to describe various example structural portions and elements of the present application, these terms are used herein for convenience of description only and are determined based on the example orientations shown in the drawings. Because the embodiments disclosed herein may be arranged in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting.

It will be appreciated by those skilled in the art that the exhaust gas or gases described in this embodiment refer to a largely gaseous composition, which may also include a portion of the composition in the form of a mist or particulate.

Fig. 1A shows a simplified block diagram of an exhaust gas purification system according to one embodiment of the present application, for illustrating the connection relationship of the various parts of the exhaust gas purification system 100. As shown in fig. 1A, the exhaust gas purification system 100 is disposed outside the reflow oven hearth 118 and is connected to the reflow oven hearth 118. When the reflow oven uses a substantially inert gas (e.g., nitrogen) as the working gas, the exhaust gas purification system 100 receives the exhaust gas exhausted from the hearth 118 of the reflow oven and conveys the purified gas back into the hearth 118. When the reflow oven uses air as the working gas, the exhaust gas purification system 100 receives exhaust gas discharged from the hearth 118 of the reflow oven, and the purified gas may be returned to the hearth 118 or may not be returned to the hearth 118, but may be discharged to the outside of the hearth 118. In FIG. 1A, the exhaust gas purification system 100 delivers purified gas back into the furnace 118.

As shown in fig. 1A, the exhaust gas purification system 100 includes a first stage cooling unit 110, a second stage cooling unit 120, and a filtering unit 130, which are sequentially connected and connected to the furnace 118 to purify exhaust gas discharged from the furnace 118. The exhaust gas purification system 100 can also deliver purified gas back to the furnace 118. Also, the exhaust gas purification system 100 is also capable of self-cleaning the first stage cooling unit 110, the second stage cooling unit 120, and the filtering unit 130 and the connection passages therebetween.

Specifically, the first stage cooling unit 110 has an exhaust gas inlet 111.1, a self-cleaning gas inlet 114, a gas outlet 111.2 and a first waste liquid outlet 141.1. The second stage cooling unit 120 has a gas inlet 121.1, a gas outlet 121.2 and a waste liquid outlet 141.2. The filter unit 130 has a gas inlet 131.1, a self-cleaning gas outlet 134, a clean gas outlet 131.2 and a waste liquid outlet 141.3.

The exhaust gas inlet 111.1 of the first stage cooling unit 110 is controllably in fluid communication with the high temperature zone of the furnace 118 via valve means 117.1. The gas outlet 111.2 of the first stage cooling unit 110 is in fluid communication with the gas inlet 121.1 of the second stage cooling unit 120 via a connecting channel 125.1. The gas outlet 121.2 of the second stage cooling unit 120 is in fluid communication with the gas inlet 131.1 of the filter unit 130 via a connecting channel 125.2, and the clean gas outlet 131.2 of the filter unit 130 is controllably in fluid communication with the low temperature zone of the furnace 118 via a valve member 117.2. Thus, the exhaust gas discharged from the furnace 118 can be purified by the first stage cooling unit 110, the second stage cooling unit 120, and the filter unit 130 in this order and then returned to the furnace 118.

Furthermore, the self-cleaning gas outlet 134 of the filter unit 130 is connected to the gas inlet 114 of the first stage cooling unit 110 via a connection channel 135, the connection channel 135 being provided with a channel switching member 117.5 for controllably fluidly connecting the self-cleaning gas outlet 134 of the filter unit 130 to the gas inlet 114 of the first stage cooling unit 110. Thus, the gas exiting the self-cleaning gas outlet 134 of the filter unit 130 can enter the first stage cooling unit 110 and can flow through the first stage cooling unit 110 and the second stage cooling unit 120 in sequence, and back into the filter unit 130, to form a self-cleaning gas circulation inside the exhaust gas purification system 100.

According to one embodiment of the present application, the first stage cooling unit 110 may not be provided with a self-cleaning gas inlet 114 separate from the exhaust gas inlet 111.1, but with the same inlet as the exhaust gas inlet and the self-cleaning gas inlet. Likewise, the filter unit 130 may not be provided with a self-cleaning gas outlet 134 separate from the clean gas outlet 131.2, but the same outlet may be used as the self-cleaning gas outlet 134 and the clean gas outlet 131.2.

The exhaust gas purification system 100 further includes a gas-supplementing port 112 provided on the first-stage cooling unit 110 and a gas-exhausting port 132 provided on the filtering unit 130, and a gas concentration detecting member for detecting the concentration of the gas in the filtering unit 130. As one example, the gas concentration detecting means is an oxygen concentration detecting means 155, by which the concentration of the working gas is detected to obtain the concentration of the working gas. Wherein the oxygen concentration detection member 155 is disposed near the exhaust port 132. The make-up port 112 is controllably opened and closed by the valve member 117.3 and the exhaust port 132 is controllably opened and closed by the valve member 117.4. When the reflow oven uses a substantially inert gas (e.g., nitrogen) as the working gas, the working gas (i.e., the substantially inert gas (e.g., nitrogen)) may be replenished into the exhaust gas purification system 100 through the gas replenishment port 112, and the exhaust port 132 may be used to cooperate with the gas replenishment port 112 when the gas replenishment port 112 is in operation. The concentration of the working gas in the exhaust gas purification system 100 can be adjusted to match the concentration of the working gas in the furnace 118 by providing the gas-supplementing port 112 and the gas-exhausting port 132. The make-up port 112 may be in controllable fluid communication with a source of working gas (i.e., a substantially inert gas such as nitrogen) through valve member 117.3 and the vent 132 may be in controllable fluid communication with the atmosphere through valve member 117.4.

The filter unit 130 is provided therein with a filter member 136. Wherein the gas inlet 131.1 of the filter unit 130 is arranged on the upstream side of the filter member 136 and the self-cleaning gas outlet 134 and the clean gas outlet 131.2 are arranged on the downstream side of the filter member 136. Here, "upstream" and "downstream" are with respect to the gas flow direction in the exhaust gas purification system 100. The filter 136 may be a steel ball filter or a paper filter.

The filter unit 130 is further provided with a heating unit 133, and the heating unit 133 is located below the filter unit 136 and is used for heating the filter unit 136.

The exhaust gas purification system 100 further includes a fan 124 for driving the flow of gas in the exhaust gas purification system 100. In the embodiment shown in fig. 1A, the fan 124 is disposed in the filter unit 130. More specifically, the fan 124 is disposed above the filter element 136, with the air intake side of the fan 124 being in fluid communication with the plenum within the filter unit 130, and the air outlet side of the fan 124 being in fluid communication with the clean air outlet 131.2, the self-cleaning air outlet 134, and the air outlet 132 of the filter unit 130. In other embodiments, other fluid dynamic devices (e.g., blowers, pumps, etc.) may be used in place of the fan 124 in the embodiment shown in FIG. 1A, so long as the gas within the exhaust gas purification system 100 is driven to flow in a desired path.

The exhaust gas purification system 100 further includes a collection unit 140, and the waste liquid outlet 141.1 of the first stage cooling unit 110, the waste liquid outlet 141.2 of the second stage cooling unit 120, and the waste liquid outlet 141.3 of the filter unit 130 are all in communication with the collection unit 140 so that the liquid discharged from the first stage cooling unit 110, the second stage cooling unit 120, and the filter unit 130 can flow into the collection unit 140. The collecting unit 140 is provided with a valve member 117.6 at the inlet thereof, and when the collecting unit 140 needs to be replaced or the liquid in the collecting unit 140 is poured out, the collecting unit 140 can be disconnected from the first stage cooling unit 110, the second stage cooling unit 120 and the filtering unit 130 by closing the valve member 117.6.

The exhaust gas purification system 100 further includes temperature detection means 151,152 provided to detect temperatures in the first stage cooling unit 110 and the second stage cooling unit 120, respectively.

It should be noted that, in the embodiment shown in fig. 1, the exhaust gas purification system 100 includes two-stage cooling units, and the two-stage cooling units are in fluid communication through the connection channel 125.1. In other embodiments, only the first stage cooling unit 110 or the second stage cooling unit 120 may be included in the exhaust gas purification system.

The exhaust gas purification system 100 has an operating state and a maintenance state. In an operating state, the exhaust gas purification system 100 purifies the gas exhausted from the reflow oven chamber 118. In the maintenance state, the exhaust gas purification system 100 no longer receives the gas exhausted from the reflow oven chamber 118, but self-cleans the inside of the exhaust gas purification system 100. By controlling the opening and closing of the respective valve members 117.1,117.2,117.3,117.4,117.5,117.6, the exhaust gas purification system 100 can be switched between the operating state and the maintenance state. The flow paths of the gases in the two operating states of the exhaust gas purification system 100 of the present application are described below by taking as an example a reflow oven using a substantially inert gas (e.g., nitrogen) as the operating gas.

Fig. 1B shows the flow path of the gas when the exhaust gas purification system 100 in fig. 1A is in an operating state. As shown in fig. 1B, when the exhaust gas purification system 100 is in an operating state, the valve member 117.1,117.2,117.6 is open, the valve members 117.3 and 117.4 are closed, and the passage switching member 117.5 may be closed, or at least partially opened. The exhaust gas (temperature approximately 170 c) containing contaminants in the reflow oven chamber 118 is exhausted from the high temperature region of the chamber 118 and is cooled to a first temperature, e.g., 110-130 c, by the first stage cooling unit 110. At this temperature, organic matters such as rosin in the exhaust gas pollutant in the first stage cooling unit 110 are condensed from a gaseous state to a liquid state and can be discharged into the collecting unit 140 from the waste liquid outlet 141.1 of the first stage cooling unit 110, and the remaining part of the exhaust gas is conveyed to the second stage cooling unit 120 for further cooling. The gas entering the second stage cooling unit 120 is cooled to a second temperature, for example, 60-80 ℃, in the second stage cooling unit 120, so that other pollutant organic matters (for example, acid or ester or ether organic matters with a low condensation point) in the exhaust gas are condensed from the gas state to the liquid state, and discharged into the collecting unit 140 through the waste liquid outlet 141.2 of the second stage cooling unit 120, and the rest of the exhaust gas is conveyed to the filtering unit 130 for filtering and purifying. After the exhaust gas introduced into the filtering unit 130 is filtered, particulate and mist organic matters therein are removed, so that clean gas can be obtained. And finally, the clean gas is conveyed back to the low-temperature area of the hearth 118 of the reflow soldering furnace, so that the waste gas is purified.

If the valve member 117.5 is closed while the exhaust gas purification system 100 is in an operating state, the net gas filtered by the filtering unit 130 cannot be returned to the first stage cooling unit 110 through the connection passage 135. If the passage switching part 117.5 is opened or partially opened, a part of the net gas filtered through the filtering unit 130 can be returned to the first stage cooling unit 110 through the connection passage 135, whereby the gas in the first stage cooling unit 110 can be cooled by the cleaning net gas having a lower temperature in the filtering unit 130 to save the cooling medium for heat exchange in the first stage cooling unit 110.

Fig. 1C shows the flow direction of the gas when the exhaust gas purification system 100 is in the maintenance state. As shown in fig. 1C, when the exhaust gas purification system 100 is in the maintenance state, the valve members 117.1, 117.2, 117.3, 117.4 are opened, and the valve member 117.6 and the passage switching member 117.5 are opened. At this time, the gas in the filter unit 130 is heated by the heating means 133 in the filter unit 130, and the temperature inside the filter unit 130 can be raised, for example, to about 150 to 170 ℃. At this temperature, a part of the solid contaminants adhering to the filter member 136 is converted into a liquid state, a part is converted into a gas state, the liquid can be discharged through the waste liquid outlet 141.3 of the filter unit 130, and the gas is transferred to the first stage cooling unit 110 and the second stage cooling unit 120 through the connection passage 135 at a higher temperature. The gas in the first stage cooling unit 110 and the second stage cooling unit 110 flows back to the filtering unit 130 through the connection passage 125.1,125.2 in the above-described exhaust gas purifying process, so that the solid-form contaminant organic matters adhering to the respective components in the first stage cooling unit 110 and the second stage cooling unit 120 and the inner walls of the connection passage 125.1 and the cooling passage 125.2 are heated again to be liquid or gas, and the liquid is discharged through the waste liquid outlet 141.1 of the first stage cooling unit 110 and the waste liquid outlet 141.2 of the second stage cooling unit 120, and the gas is fed back to the filtering unit 130, thereby completing the self-cleaning gas circulation.

In the self-cleaning gas circulation process shown in fig. 1C, the self-cleaning gas circulation process can be performed without affecting the reflow oven operation, since the valve members 117.1, 117.2 are opened. That is, even if the reflow oven is in operation, the exhaust gas purification system 100 is in a maintenance state, and self-cleaning of the inside thereof is performed.

A range of concentrations of the working gas in the reflow oven hearth 118 using a substantially inert gas (e.g., nitrogen) as the working gas is required to be maintained to meet process requirements. Reflow ovens are typically provided with a unit that adjusts the concentration of the working gas in the hearth 118 (e.g., a unit that supplements the working gas). When the exhaust gas purification system 100 is in an operating state, the gas in the furnace hearth 118 of the reflow soldering furnace is continuously purified by the exhaust gas purification system 100 and returned to the furnace hearth 118 of the reflow soldering furnace, so that the concentration of the working gas in the exhaust gas purification system 100 in an operating state is similar to the concentration unit of the working gas in the furnace hearth 118 of the reflow soldering furnace. But when the exhaust gas purification system 100 is disconnected from the furnace chamber 118 of the reflow oven for self-cleaning maintenance, the concentration of the working gas in the exhaust gas purification system 100 will typically be less than the concentration of the working gas in the furnace chamber 118. Thus, according to the present application, after the maintenance state of the exhaust gas purification system 100 is completed (including maintenance procedures of self-cleaning gas circulation or other cleaning procedures), a certain amount of working gas may be replenished into the exhaust gas purification system 100 before the exhaust gas purification system 100 is re-communicated with the furnace 118 of the reflow oven so that the working gas in the exhaust gas purification system 100 reaches the same or similar concentration as the working gas in the reflow oven. For this reason, the working gas is replenished into the exhaust gas purification system 100 through the gas replenishing port 112, and at the same time, the gas in the exhaust gas purification system 100 is discharged through the gas discharging port 132 until it is judged by the gas concentration detecting means 155 that the concentration of the shielding gas in the exhaust gas purification system 100 reaches the concentration of the shielding gas in the reflow oven.

When the exhaust gas purification system 100 is used in a reflow oven using air as a working gas, the gas purified by the exhaust gas purification system 100 may be fed back into the furnace 118 or may not be fed back into the furnace 118, but may be directly discharged to the atmosphere. If the gas purified by the exhaust gas purification system 100 is discharged directly to the atmosphere, the clean gas outlet 131.2 of the filter unit 130 shown in fig. 1B is controllably in fluid communication with the atmosphere via the valve member 117.2, instead of being connected to the furnace 118.

According to the present application, the first stage cooling unit 110 and the second stage cooling unit 120 in the exhaust gas purification system 100 may employ any type of known heat exchange device.

According to the present application, the first stage cooling unit 110, the second stage cooling unit 120, and the filtering unit 130 of the exhaust gas purification system 100 may be integrated such that the entire exhaust gas purification system 100 forms a box-type exhaust gas purification device for use with a reflow oven.

Two specific structural examples of the exhaust gas purifying apparatus are described below, in which fig. 2A to 6 show specific structures of the exhaust gas purifying apparatus 200 according to one embodiment of the present application, and fig. 7A to 11 show specific structures of the exhaust gas purifying apparatus 700 according to another embodiment of the present application.

Fig. 2A to 2C are general structural schematic diagrams of the exhaust gas purifying apparatus 200, wherein fig. 2A is a perspective structural diagram of the exhaust gas purifying apparatus 200, fig. 2B is a front view of fig. 2A, and fig. 2C is a plan view of fig. 2A. As shown in fig. 2A to 2C, the exhaust gas purifying apparatus 200 includes a housing 201, the housing 201 having a substantially box shape with a cavity therein, which includes a top 202, a bottom 203, a left 204, a right 205, a front 206, and a rear 207. Wherein the top 202, bottom 203, left 204, right 205 and rear 207 portions of the housing 201 are coupled together, such as by welding, to form a tank compartment, and the front 206 is detachably coupled to the top 202 and bottom 203, such as by a snap fit, to close the tank compartment. Wherein top 202, bottom 203, left 204, right 205, and front 206 are shown in fig. 2B, and rear 207 is shown in fig. 2C.

As shown in fig. 2A-2C, the exhaust gas purification apparatus 200 further includes an exhaust gas inlet 211.1 and a clean gas outlet 231.2 provided on the housing 201. The exhaust gas inlet 211.1 is provided with a connection pipe 251.1, and the connection pipe 251.1 is provided with a valve member 217.1. The valve member 217.1 can be opened and closed. The exhaust gas inlet 211.1 is connected via a connecting line 251.1 to a high-temperature region (not shown) of the reflow oven chamber. The net gas outlet 231.2 is provided with a connecting pipe 251.2, and the connecting pipe 251.2 is provided with a valve member 217.2. The valve member 217.2 can be opened and closed. The clean air outlet 231.2 is connected to the reflow oven furnace low temperature zone (not shown) via a connecting line 251.2. The exhaust gas discharged from the furnace chamber can enter the exhaust gas purifying device 200 from the exhaust gas inlet 211.1, is purified into purified gas by the exhaust gas purifying device 200, and is discharged to the low-temperature region of the furnace chamber of the reflow soldering furnace from the purified gas outlet 231.2.

The exhaust gas inlet 211.1 is provided at the rear of the right part 205 of the housing 201, and the clean gas outlet 231.2 is provided at the left of the rear part 207 of the housing 201, as seen from the front of the exhaust gas purification device 200, whereby the flow direction of the exhaust gas in the exhaust gas purification device 200 is made to be substantially right-to-left.

The front 206 of the housing 201 comprises a first front plate 206.1 and a second front plate 206.2. Wherein the first front plate 206.1 is used to seal a portion of the cavity (see filter cavity 342 in fig. 3) inside the housing 201 from the front side direction, and the second front plate 206.2 is used to seal another portion of the cavity (see cooling cavity 341 in fig. 3) inside the housing 201 from the front side direction. Wherein the second front plate 206.2 is provided with a plurality of openings 271 for inserting the cooling device into the cooling cavity 341 through the openings 271 in the second front plate 206.2 (which will be described in detail with reference to fig. 3).

The exhaust gas purifying device 200 further includes a collecting device connected to the bottom 203 of the housing 201. In the example shown, the collection device comprises two collection bottles 240.1 and 240.2, each of which is connected to the bottom 203 of the housing 201 by a valve member 217.6 so that contaminants which condense into liquid can be controllably discharged into the collection bottles 240.1 and 240.2. The bottom 203 comprises a bottom plate which slopes gradually downwards in a direction from back to front, and the collection bottles 240.1 and 240.2 are attached to the front side of the bottom plate (see fig. 4). The collection bottle 240.1 is adapted to communicate with a filter volume 342 (see fig. 3) inside the housing 201, and the collection bottle 240.2 is adapted to communicate with a cooling volume 341 (see fig. 3) inside the housing 201. By providing an inclined bottom plate, the contaminants that condense into liquid can be made to flow into the collecting device more easily.

The exhaust gas purification apparatus 200 further includes an exhaust port 232 and a make-up port 212 (see fig. 2C). As one example, the make-up port 212 is disposed on the top 202 of the housing 201 near the exhaust gas inlet 211.1. The vent 232 is disposed on the connecting conduit 251.1 at the clean air outlet 231.2 and is located at a position between the clean air outlet 231.2 and the valve member 217.1. The bottom of the connecting pipe 251.1 at the net gas outlet 231.2 is provided with an oxygen concentration detection device 455 (see fig. 4), the oxygen concentration detection device 455 being adapted to detect the oxygen concentration in the gas exiting at the net gas outlet 231.2. Accordingly, the flow direction of the shielding gas that supplements the exhaust gas purification device 200 is also substantially from right to left, so that the concentration of the working gas in the entire exhaust gas purification device 200 can be increased. The exhaust port 232 and the air supply port 212 are respectively provided with a valve member by which the opening or closing of the exhaust port 232 and the air supply port 212 is controlled, for example, by a solenoid valve. It should be appreciated by those skilled in the art that in order to maintain the gas pressure in the exhaust gas purification apparatus 200 within a certain range, the valve members on the exhaust port 232 and the make-up port 212 should be opened simultaneously or closed simultaneously. Of course, the exhaust port 232 and the air supply port 212 may be provided at other positions as long as it is possible to controllably input the gas into the exhaust gas purification apparatus 200 through the air supply port 212 and controllably discharge the gas purification apparatus 200 through the exhaust port 232. The exhaust gas purification apparatus 200 further includes a blower 224. The drive components of the blower 224 are disposed on the left side of the top 202 of the housing 201, and the impeller of the blower 224 is disposed within a filter volume 342 (see fig. 5) within the housing 201. The impeller of blower 224 has an air intake side in fluid communication with filtration volume 342 and an air outlet side in fluid communication with clean air outlet 231.2.

The exhaust gas purification apparatus 200 further includes temperature detectors 213.1, 213.2, 213.3, 213.4, 213.5, and 213.6. Among them, temperature detectors 213.1 and 213.2 are respectively disposed at the exhaust gas inlet 211.1 and the clean gas outlet 231.2, and temperature detectors 213.3, 213.4 and 213.5 are connected to the rear 207 of the housing 201 and extend into the cooling chamber 341 (see fig. 5) of the exhaust gas purification apparatus 200. The temperature sensor 213.6 is connected to the left part 204 of the housing 201 and protrudes into the filter chamber 342 (see fig. 5) of the exhaust gas purification device 200. As one example, temperature detectors 213.1, 213.2, 213.3, 213.4, 213.5, and 213.6 are thermocouples. In other examples, the exhaust gas purifying device 200 may also include only a portion of the temperature detector or be provided with other types of temperature detectors.

The exhaust gas purifying apparatus 200 further includes a plurality of heating rods 222. The heating rod 222 is also connected to the left portion 204 of the housing 201 and protrudes into the filter chamber 342 (see fig. 5) of the exhaust gas purification apparatus 200 to heat the filter member 336 (see fig. 5) in the filter chamber 342 during self-cleaning of the exhaust gas purification apparatus 200. Other heating devices may be substituted for the heating rod 222 in other examples. Of course, the heating rod 222 may not be included in the exhaust gas purifying apparatus that does not require self-cleaning.

Fig. 3 is an exploded construction view of the exhaust gas purifying device 200 for illustrating the internal structure and components of the exhaust gas purifying device 200. As shown in fig. 3, the inside of the case 201 includes a partition plate 437 (see fig. 4 for a specific structure of the partition plate 437), the partition plate 437 dividing the cavity inside the case 201 into a cooling cavity 341 and a filtering cavity 342, the cooling cavity 341 being located on the right side of the filtering cavity 342. The partition plate 437 has an upper opening 432 and a lower opening 431 (see fig. 4), and the upper opening 432 and the lower opening 431 can communicate the cooling capacity 341 and the filtering capacity 342. The cooling plenum 341 communicates with the exhaust gas inlet 211.1 and the filter plenum 342 communicates with the clean gas outlet 231.2. A cooling means is provided in the cooling reservoir 341 for reducing the temperature of the gas in the cooling reservoir 341. The cooling means comprises a first stage cooling means 310 and a second stage cooling means 320, the first stage cooling means 310 being located to the right of the second stage cooling means 320. After entering the cooling chamber 341 from the exhaust gas inlet 211.1, the gas flows through the first stage cooling device 310 and the second stage cooling device 320 in that order from right to left. A filter element 336 is provided in the filter volume 342, the filter element 336 being mounted transversely in the filter volume 342 such that gas can flow through the filter element 336 from below to above after entering the filter volume 342 to exit the filter volume 342 from a clean gas outlet 231.2 above the filter element 336.

Also provided in the cooling chamber 341 is a shroud 327, which shroud 327 is arranged on the top rear side of the cooling device, the shroud 327 together with the housing 201 forming part of a connection channel through which the self-cleaning gas flows, as will be described in more detail later.

After the exhaust gas is discharged from the high temperature region of the reflow oven hearth, the exhaust gas enters the exhaust gas purification device 200 from the exhaust gas inlet 211.1, wherein pollutants such as rosin in the exhaust gas are condensed into liquid state from gas state through the cooling cavity 341 by the first stage cooling device 310 and the second stage cooling device 320 and are discharged into the collecting bottle 240.2, the residual gas in the exhaust gas flows into the filtering cavity 342 through the opening 431, is filtered into clean gas by the filtering component 336 in the filtering cavity 342, and finally the clean gas is discharged from the clean gas outlet 231.2 to the low temperature region of the reflow oven hearth.

It should be noted that, the cooling chamber 341 may be disposed at the left side of the filtering chamber 342, but in this case, the exhaust gas inlet 211.1 needs to be located at the left portion 204 of the housing so as to be in communication with the cooling chamber 341, and the clean gas outlet 231.2 needs to be located at the right portion 205 of the housing so as to be in communication with the filtering chamber 342.

As also shown in fig. 3, the first stage cooling device 310 includes a plurality of cooling plates 315 and the second stage cooling device 320 includes a plurality of cooling plates 317. Each cooling plate 315, 317 may contain a cooling medium therein. The cooling medium in the cooling plates 315, 317 exchanges heat with the exhaust gas through the outer peripheral side walls of the cooling plates 315, 317, causing the temperature of the exhaust gas to decrease. Each of the plurality of openings 271 of the second front plate 206.2 of the housing is sized to match the size of a respective one of the cooling plates 315 or 317 such that each cooling plate 315 or 317 is capable of sealing the respective opening 271 after insertion into the respective opening 271. The end plate of each cooling plate 315 or 317, which is located outside the housing 201, is provided with a cooling medium inlet 355 or 357 through which cooling medium can be introduced into the corresponding cooling plate 315 or 317 and a cooling medium outlet 365 or 367 through which cooling medium in the corresponding cooling plate 315 or 317 can be discharged. The cooling medium inlet 355 or 357 and the cooling medium outlet 365 or 367 may be enclosed.

In the embodiment shown in fig. 3, the cooling medium in the plurality of cooling plates 315 of the first stage cooling device 310 is compressed gas and the cooling medium in the plurality of cooling plates 317 of the second stage cooling device 320 is air. A muffler 208 (see fig. 2A) is provided at the cooling medium outlet 365 of the plurality of cooling plates 315 of the first stage cooling device 310 to reduce noise caused by the flow of the compressed gas. A filter screen is further provided at the cooling medium inlet 357 of the several cooling plates 317 of the second stage cooling device 320, and a gas duct 318 and a suction fan 319 are connected to enable air to be input from the cooling medium inlet 357 and output from the cooling medium outlet 367 at a certain speed. Of course, other types of cooling media, such as cooling water, etc., may be selected by those skilled in the art depending on the actual operating environment.

Fig. 4 is a sectional view taken along the line A-A in fig. 2B for showing a specific structure of the partition plate 437. As shown in fig. 4, a partition plate 437 is connected between the top 202 and the bottom 203 of the housing 201 inside the housing 201 for partitioning the cooling chamber 341 from the filtering chamber 342. The partition plate 437 is provided with an upper opening 432 and a lower opening 431, wherein the upper opening 432 is disposed higher in position than the filter member 336 (not shown in fig. 4) in the housing, and the lower opening 431 is disposed lower in position than the filter member 336 (not shown in fig. 4) in the housing. Wherein the upper opening 432 is in fluid communication with an air outlet side 584 of an impeller 580 of the blower 224 (see fig. 5).

The shroud 327 is L-shaped in cross section and includes a cross-plate 425 and a riser 426 that are connected to one another, wherein the cross-plate 425 abuts or substantially abuts the rear portion 207 of the housing 201 and the riser 426 abuts the top portion 202 of the housing 201 such that the shroud 327 and the housing 201 together form a connecting channel 635 (see fig. 6). The connection channel 635 is aligned with and communicates with the upper opening 432 of the partition plate 437 such that gas in the filter volume 342 can enter the connection channel 635 through the upper opening 432 of the partition plate 437.

Thereby, the gas in the cooling plenum 341 can flow into the filtering plenum 342 through the lower opening 431, flowing from bottom to top in the filtering plenum 342 to be filtered as clean gas by the filtering component 336. And, a part of the net gas filtered in the filtering cavity 342 can be discharged to the reflow oven through the net gas outlet 231.2, and the other part of the net gas flows through the connection channel 635 through the upper opening 432 and then flows back to the cooling cavity 341.

Fig. 5 is a sectional view taken along line B-B of fig. 2C, for illustrating specific structures of the first stage cooling device 310, the second stage cooling device 320, and the filter member 336, and illustrating a flow path of gas during the exhaust gas purification process. As shown in fig. 5, the first stage cooling device 310 includes four cooling plates 315, and the second stage cooling device 320 includes two cooling plates 317.

Four cooling plates 315 are arranged in the lateral direction of the housing 201 (i.e., in the left-right direction). Each cooling plate 315 has a cavity 546.1, the cavity 546.1 being in communication with a cooling medium inlet 355 and a cooling medium outlet 365 in the housing 201 such that compressed air can flow as cooling medium into and out of the cavity 546.1 of the cooling plate 315. The two cooling plates 317 are also arranged in a lateral direction (i.e. in a left-right direction), each cooling plate 317 having a cavity 546.2, the cavities 546.2 being in communication with a cooling medium inlet 357 and a cooling medium outlet 367 on the housing 201, so that air can flow into and out of the cavities 546.2 of the cooling plates 317 as cooling medium. Each of the cooling plates 315 and 317 is made of a thermally conductive material, such as metal, so that the gas surrounding the cooling plates 315 and 317 can exchange heat with the cooling medium contained within the cooling plates 315 and 317. By adjusting the speed at which the cooling medium flows into or out of the cooling plates 315 and 317, the gas in the first stage cooling device 310 and the second stage cooling device 320 can be cooled to a temperature range.

Each cooling plate 315,317 is vertically disposed (i.e., disposed in a direction perpendicular to the housing top 202 and bottom 203) with a vertical gas channel 548 formed between each two adjacent cooling plates. Each cooling plate 315,317 has left and right side walls, and as the exhaust gas in the cooling plenum 341 flows through the vertical gas passage 548, the exhaust gas exchanges heat with the cooling medium within the cavities 546.1 and 546.2 through the left and right side walls of the cooling plates 315,317, causing the temperature of the exhaust gas to decrease. As the exhaust gas decreases, a portion of the contaminants in the exhaust gas can condense into a liquid and flow down the left and right sidewalls of the cooling plates 315,317 to the bottom 203 of the housing. In addition, the leftmost cooling plate forms vertical gas passages 548 with the partition plate 437 on the left side in addition to the vertical gas passages 548 with the adjacent cooling plate on the right side. Also, for the rightmost cooling plate, in addition to the vertical gas passages 548 formed between adjacent cooling plates to the left thereof, the cooling plate also forms vertical gas passages 548 with the right 205 of the housing.

And, each cooling plate 315,317 also forms a bottom transverse gas passage 549.2 with the housing bottom 203 or a top transverse gas passage 549.1 with the housing top 202. Wherein each of the top lateral gas passage 549.1 and the bottom lateral gas passage 549.2 communicates with at least one of the vertical gas passages 548 to form a gas passage 550 for the flow of exhaust gas. As one example, the top lateral gas channels 549.1 and the bottom lateral gas channels 549.2 are alternately arranged in the arrangement direction of the cooling plates 315,317 to form a curved gas channel 550 as shown in fig. 5. Wherein the exhaust gas inlet 211.1 communicates with the rightmost vertical gas channel 548, the lower opening 431 of the partition plate communicates with the leftmost vertical gas channel 548, such that exhaust gas can flow from the rightmost vertical gas channel 548 into the gas channel 550 and out of the gas channel 550 from the leftmost vertical gas channel 548. In other embodiments, the top transverse gas channels, the bottom transverse gas channels, and the vertical gas channels may be arranged in other arrangements to form other gas channels, as long as the exhaust gas is guaranteed to flow in the gas channels and through each cooling plate.

As will be appreciated by those skilled in the art, in this embodiment, to form the curved gas channel 550, each cooling plate 315,317 forms only one of the bottom lateral gas channel 549.2 or the top lateral gas channel 549.1. When a bottom transverse gas passage 549.2 is formed between the cooling plates 315,317 and the housing bottom 203, the cooling plates 315,317 need to abut or otherwise block a gap therebetween such that fluid cannot flow between the cooling plates 315,317 and the housing top 202. Likewise, when a top transverse gas passage 549.2 is formed between the cooling plates and the housing top 202, the cooling plates 315,317 need to abut or otherwise block a gap therebetween such that fluid cannot flow between the cooling plates 315,317 and the housing bottom 203.

In the embodiment shown in FIG. 5, there are three cooling plates 315,317 forming a top transverse gas passage 549.1 between the housing top 202. A set of seal plates 554 attached to the housing bottom 203 are provided at the locations where the three cooling plates 315,317 are adjacent the housing bottom 203. Each set of seal plates 554 includes two seal plates 554 that abut against the left and right sides of the lower portion of the corresponding cooling plate 315,317, respectively, to block the gap between the cooling plate 315,317 and the housing bottom 203 so that fluid cannot flow between the cooling plate 315,317 and the housing bottom 203. By providing the seal plates 554, fluid flow between the cooling plates 315,317 and the housing bottom 203 is blocked even when the housing bottom 203 is in the sloped shape shown in FIG. 4. Of course, the person skilled in the art may also directly design the shape of the cooling plate without the sealing plate 554, so that the cooling plate matches the shape of the housing bottom 203.

As shown in fig. 5, the temperature detector 213.3 is used to detect the gas temperature at the gas inlet of the first stage cooling device 310, the temperature detector 213.4 is used to detect the gas temperature at the gas outlet of the first stage cooling device 310, the temperature detector 213.5 is used to detect the gas temperature at the gas outlet of the second stage cooling device 320, and the temperature detector 213.6 is used to detect the gas temperature in the filter device. These temperature detectors are capable of detecting the gas temperature in the exhaust gas purification device 200 in real time and adjusting the flow rate of the cooling medium according to the temperature condition. When the detected gas temperature is too high, or the influence of the adjustment of the flow rate of the cooling medium on the gas temperature is less pronounced, the exhaust gas purification apparatus 200 may need to be self-cleaned.

The filter member 336 is disposed in the middle of the filter chamber 342, dividing the filter chamber 342 into an upper sub-chamber and a lower sub-chamber, wherein the lower sub-chamber is in communication with the lower opening 431 of the divider plate, and the impeller 580 of the blower 224 is disposed in the upper sub-chamber such that the air inlet side 582 of the impeller 580 of the blower 224 is in fluid communication with the upper sub-chamber. The air outlet side 584 of the impeller 580 of the blower 224 is in fluid communication with the clean air outlet 231.2 and the upper opening 432 of the divider plate. When the impeller 580 rotates, gas can flow in the direction of the arrow shown in fig. 5 in the cooling chamber 341 and the filtering chamber 342. As an example, the filtering component 336 is a steel ball filter mesh, which is advantageous for heat conduction on the one hand, and can be cleaned for reuse and cost saving on the other hand.

It should be noted that, in the case where the cooling chamber is kept to a certain size, the lateral width of the cooling plate 315 of the first stage cooling device 310 should be as small as possible while accommodating a sufficient cooling medium, so that rosin condensed into a liquid when the exhaust gas flows through the first stage cooling device 310 can be less accumulated on the top of the cooling plate 315. Thus, a smaller transverse width but a greater number of cooling plates 315 are included in the first stage cooling device 310, while a larger transverse width but a lesser number of cooling plates 317 are included in the second stage cooling device 320. In the embodiment shown in FIG. 5, the lateral width of the cooling plates 315 of the first stage cooling device 310 is one third of the lateral width of the cooling plates 317 of the second stage cooling device 320. In other embodiments, other numbers of cooling plates 315,317 may be provided, and the lateral widths of the cooling plates 315 and 317 may be other ratios, as long as it is ensured that the cooling medium contained in the cooling plates 315,317 is sufficient to cool the exhaust gas to the desired temperature.

Fig. 6 is a schematic perspective view of the cooling device in the exhaust gas purification device 200 in fig. 5, for illustrating the specific structure and positional relationship of the cooling plate, the partition plate 437 and the shroud 327, to explain the flow path of the self-cleaning gas circulation process. To show the internal structure of the cooling plates 315,317, the end plates of the cooling plates 315,317 (i.e., the end plates provided with the cooling medium inlet and outlet shown in fig. 3) are removed in fig. 6. As shown in fig. 6, the partition plate 437, the cooling plate 544, and the cooling plate 543 in the exhaust gas purification device 200 are vertically placed substantially in parallel and spaced apart from each other to form the gas passage 550 as described above.

Among them, the shroud 327 is provided at the rear side and above the cooling plates 544 and 543, and extends in the left-right direction. As an example of an arrangement, a part of the cooling plate, for example, a part of the cooling plate forming the bottom lateral gas passage 549.2 with the housing bottom 203, is provided with a step-shaped support portion on the top rear side thereof. The step-shaped support is for receiving an L-shaped shroud 327. This arrangement can make the structure of the exhaust gas purification apparatus 200 more compact. It should be appreciated by those skilled in the art that the shroud 327 may not be L-shaped or that no support is provided on the cooling plate, etc., as long as the cooling plate, shroud 327, and housing are sealed as desired to form the gas channel 550.

With the above arrangement, the shroud 327 can form a connection channel 635 with the housing 201, the connection channel 635 having a self-cleaning gas outlet 634 and a self-cleaning gas inlet 614 at both ends, wherein the self-cleaning gas outlet 634 is in communication with the upper opening 432 of the partition plate 437, the self-cleaning gas inlet 614 being in fluid communication with the cooling plenum 341 at the first stage cooling device 310. As an example, the self-cleaning gas inlet 614 is located near the exhaust gas inlet 211.1.

As an example, the upper opening 432 of the partition plate 437 may be sized to allow the gas in the filter volume 342 to controllably flow into the connecting channel 635. In the embodiment of the present application, an adjustable baffle 638 is movably connected to the partition plate 437, and the adjustable baffle 638 can be moved back and forth to cover the upper opening 432 or to open the upper opening 432, and also the opening size of the upper opening 432 can be adjusted. The adjustable baffle 638 is provided with a guide groove 661, and the partition plate 437 is provided with a guide pin 662 inserted into the guide groove 661, thereby realizing movable connection between the adjustable baffle 638 and the partition plate 437.

Thus, when the exhaust gas purification apparatus 200 is in the maintenance state, the gas in the filter volume 342 can be caused to flow into the connection passage 635 through the upper opening 432, and to flow to the first-stage cooling apparatus 310 through the connection passage 635.

As also shown in fig. 6, a flow equalizer plate 656.1 is included in the cavity 546.1 inside the cooling plate 315, and likewise, a flow equalizer plate 656.2 is included in the cavity 546.2 inside the cooling plate 317, each of which is provided with a plurality of through holes. As an example, the flow equalization plate 656.1 is uniformly provided with a plurality of circular holes 658.1, and the flow equalization plate 656.2 is provided with a plurality of elongated holes 658.2. Flow equalization plates 656.1 and 656.2 are provided on the flow paths of the cooling medium in the cavities 546.1 and 546.2, respectively, so that the cooling medium can pass through the through holes and flow uniformly and stably. For the cooling plate 317, air flows from the cooling medium inlet 357 into the cooling plate cavity 546.2, from bottom to top through the flow equalizer 656.2, and then out the cooling medium outlet 367, exchanging heat with the exhaust gas through the side walls of the cooling plate 317. For the cooling plate 315, the compressed gas flows from the cooling medium inlet 355 into the cavity 546.1 of the cooling plate 315, from bottom to top through the flow equalization plate 656.1, and then out the cooling medium outlet 365, exchanging heat with the exhaust gas through the side walls of the cooling plate 315.

The exhaust gas is substantially purified in the exhaust gas purifying apparatus 200 as follows: exhaust gas (temperature approximately 170 c) containing contaminants is discharged from the high temperature zone of the reflow oven chamber and then enters the gas channel 550 from the exhaust gas inlet 211.1. The exhaust gas is cooled to about 110-130 c (the temperature of the gas at the outlet of the first stage cooling device 310, as measured by the temperature detecting device 213.4) by adjusting the flow of compressed air into and out of the cooling plate 315 as it passes through the cooling plate 315 in the first stage cooling device 310, at which temperature the rosin and other organic substances such as flux in the exhaust gas condense from a gaseous state to a liquid state and can be discharged into the collection bottle 240.2. The remainder of the exhaust gas flows through the cooling plates 317 in the second stage cooling device 320, and by adjusting the flow of air into and out of the cooling plates 317, the remainder of the exhaust gas is cooled to about 60-80 ℃ (the temperature of the gas at the outlet of the second stage cooling device 320, as measured by the temperature detection device 213.5), at which temperature other contaminant organics in the exhaust gas, such as low-condensation point acid or ester or ether organics, condense from a gaseous state to a liquid state and can be discharged into the collection bottle 240.2. The remaining part of the exhaust gas flows into the filtering receptacle 342 through the lower opening 431 of the partition plate 437, and then flows through the filtering part 336 from bottom to top, and is filtered by the filtering part 336 to remove particulate and mist organic matters therein, so as to obtain clean air. Finally, most of the clean gas is discharged from the clean gas outlet 231.2 to the low temperature zone of the reflow oven furnace, the cleaning process of the exhaust gas is completed, and a small portion of the clean gas can flow back into the first stage cooling device 310 through the upper opening 432 and the connection channel 635 to mix with the exhaust gas and reduce the temperature of the exhaust gas. Adjusting the opening size of the upper opening 431 may vary the amount of net gas flowing back into the first stage cooling device 310 through the upper opening 432 and the connecting passage 635. Of course, it is also possible to completely close the upper opening 431, preventing clean air from being able to flow back into the first stage cooling device 310 via the upper opening 432 and the connecting channel 635.

The self-cleaning process of the exhaust gas purifying device 200 is as follows: the exhaust gas inlet 211.1 and the clean gas outlet 231.2 are closed by the valve members 217.1 and 217.2 and the gas in the filter volume 342 is heated by the heater 222 until the temperature in the filter volume 342 rises to about 150 ℃ -170 ℃ (as measured by the temperature sensing device 213.6) so that a portion of the solid contaminants adhering to the filter member 336 are converted to a liquid state and a portion are converted to a gaseous state, wherein the liquid contaminants flow to the housing bottom 203. The high-temperature gaseous pollutants flow from bottom to top to the upper opening 432 of the partition plate under the action of the blower 224, then flow through the connection channel 635 and are conveyed back to the first stage cooling device 310 and the second stage cooling device 320, and the solid-state pollutants attached to the surfaces of the inner wall of the casing, the outer wall of the cooling device, the shroud 327, the filtering component 336 and other components in the exhaust gas purifying device 200 are reheated to be liquid so as to be cleaned. Wherein the liquid contaminants of the bottom 203 of the housing are collected by the collecting means 240.1 and 240.2.

After the self-cleaning process is completed, the working gas such as nitrogen gas is supplied to the exhaust gas purification apparatus 200 through the gas supply port 212, and the gas in the exhaust gas purification apparatus 200 is discharged from the gas discharge port 232. After the oxygen concentration in the exhaust gas purification device 200 is detected to meet the requirement, the exhaust gas purification device 200 is communicated with the hearth of the reflow oven.

Fig. 7A to 11 show the structure of an exhaust gas purifying apparatus 700 according to another embodiment of the present application, wherein the exhaust gas purifying apparatus 700 differs from the exhaust gas purifying apparatus 200 mainly in the specific structure of the cooling apparatus.

Fig. 7A to 7C are general structural schematic diagrams of the exhaust gas purifying apparatus 700, wherein fig. 7A is a perspective structural diagram of the exhaust gas purifying apparatus 700, fig. 7B is a front view of fig. 7A, and fig. 7C is a top view of fig. 7A. As shown in fig. 7A to 7C, the exhaust gas purifying apparatus 700 includes a housing 701, the housing 701 having a similar structure to the housing 201 of the exhaust gas purifying apparatus 200, including a top 702, a bottom 703, a left 704, a right 705, a front 706, and a rear 707, and the detailed description thereof will not be repeated.

The clean gas outlet 731.2 of the exhaust gas purification device 700 is arranged to the left in the rear section 707 of the housing 701. Unlike the exhaust gas inlet 211.1 of the exhaust gas purification device 200, the exhaust gas inlet 711.1 of the exhaust gas purification device 700 is provided on the rear portion 707 of the housing 701, and the exhaust gas inlet 711.1 is provided right of the rear portion 707 of the housing 701. Correspondingly, the air supply port 712 is also provided on the rear side of the top 702 of the housing 701, in the vicinity of the exhaust gas inlet 711.1. While the positions of the exhaust port 732 and the oxygen concentration detection device 955 (see fig. 9) remain unchanged.

The front 706 of the housing 701 includes a first front plate 706.1 and a second front plate 706.2.

Wherein, the second front plate 706.2 is also provided with a plurality of openings 771 for inserting the cooling device into the second cooling cavity 862. The exhaust gas purification device 700 further includes collection bottles 740.1 and 740.2 attached to the bottom 703 of the housing and a fan 724 attached to the top 702 of the housing.

Fig. 8 is an exploded view of the exhaust gas purifying apparatus 700 for illustrating the cooling compartment 841 and the filtering compartment 842 inside the exhaust gas purifying apparatus 700 to illustrate the flow direction of the gas in the exhaust gas purifying apparatus 700. As shown in fig. 8, the interior of the housing 701 includes a partition plate 937 (the structure of the partition plate 937 is the same as that of the partition plate 437, see fig. 9 in particular), the partition plate 937 partitions the interior of the housing 701 into a cooling capacity 841 and a filtration capacity 842, and the cooling capacity 841 and the filtration capacity 842 communicate through a lower opening 931 (see fig. 9) of the partition plate 937. The cooling cavity 841 includes a first cooling cavity 861 and a second cooling cavity 862, a first stage cooling device 810 is disposed in the first cooling cavity 861, a second stage cooling device 820 is disposed in the second cooling cavity 862, and gas flows through the first stage cooling device 810 and the second stage cooling device 820 from right to left after entering the cooling cavity 841 from the exhaust gas inlet 711.1. The filter volume 842 includes a filter element 836 therein, and after entering the filter volume 842, the gas flows through the filter element 836 from bottom to top, and is able to flow out of the filter volume 842 from the clean gas outlet 731.2. The structure of the second stage cooling device 820 is the same as that of the second stage cooling device 320 in the exhaust gas purifying device 200, and will not be described here again. The upper rear side of the second-stage cooling device 820 is provided with an L-shaped shroud 827, unlike the shroud 327 in the exhaust gas purification device 200 shown in fig. 2A-6, the shroud 827 is provided only at the second-stage cooling device 820.

As also shown in fig. 8, the first stage cooling device 810 includes cooling fins 863 and cooling tubes 865, each cooling tube 865 having a cooling medium contained therein, the cooling medium in the cooling tubes 865 being in heat exchange relationship with the exhaust gas via the cooling fins 863. The second stage cooling device 820 includes a plurality of cooling plates 817 therein, the cooling plates 817 being sized to match openings 771 in the second front plate 706.2. Wherein, as can be seen from the front of the housing, the first stage cooling device 810 is provided with a cooling medium inlet 855 and a cooling medium outlet 815, and the second stage cooling device 820 is provided with a cooling medium inlet 857 and a cooling medium outlet 816. It should be noted that the two sets of cooling medium inlets 855 and cooling medium outlets 815 are not arranged side by side, wherein one set of cooling medium inlets 855 and cooling medium outlets 815 are closer together and the other set of cooling medium inlets 855 and cooling medium outlets 815 are farther apart (see fig. 7B). Wherein in the embodiment shown in fig. 8, the cooling medium in cooling tubes 865 of first stage cooling device 810 is compressed gas and the cooling medium in the plurality of cooling plates 817 of second stage cooling device 820 is air. A muffler 708 is also provided at each cooling medium outlet 815 of the first stage cooling device 810.

Fig. 9 is a sectional view taken along the line A-A in fig. 7B for illustrating a specific structure of the partition plate 937. The partition plate 937 is similar in structure to the partition plate 437 in the exhaust gas purification apparatus 200 shown in fig. 2A to 6, and also has an upper opening 932 and a lower opening 931. And shroud 827 includes cross plate 925 and riser 926 that cooperate with housing 701 to form connecting channel 1135 (see fig. 11). Wherein the upper opening 932 is also in fluid communication with an air outlet side 1084 (see fig. 10) of an impeller 1080 of the fan 724.

Fig. 10A and 10B are diagrams for illustrating specific structures of the first stage cooling device 810, the second stage cooling device 820, and the filter member 836 to explain the flow path of the gas during the exhaust gas purification. Wherein fig. 10A is a sectional view taken along line B-B in fig. 7C, fig. 10B is a sectional view taken along line C-C in fig. 10A, and only the first cooling device 810 is shown in fig. 10B with other components removed for more clarity in illustrating the specific structure of the first cooling device 810.

As shown in fig. 10A and 10B, the first stage cooling device 810 includes four layers of cooling fins 863 and four layers of cooling tubes 865, the four layers of cooling tubes 865 containing a cooling medium therein. Wherein the cooling pipe 865 is connected to the cooling fin 863, and the temperature of the exhaust gas is lowered by heat exchange between the cooling fin 863 and the exhaust gas.

Wherein four cooling fins 863 are arranged longitudinally (i.e., vertically), each cooling fin 863 is disposed laterally (i.e., laterally) with a certain spacing between adjacent cooling fins 863. The cooling tube 865 has a cavity 1046.1. The cooling fins 863 are made of a thermally conductive material, such as metal, so that the exhaust gases in the first cooling volume 861 can exchange heat with the cooling medium in the cavities 1046.1 of the cooling tubes 865 by heat transfer from the cooling fins 863.

Each layer of cooling fins 863 is generally U-shaped having a through slot 1064 and a side slot 1072 (see also fig. 11), wherein the through slot 1064 is provided in the bottom 1066 of the cooling fin 863 and extends in the left-right direction. The exhaust gas passes through channels 1064 in the bottom of the cooling fins 863, forming a longitudinal gas flow 1068 from top to bottom. Since the exhaust gas inlet 711.1 is provided at the rear side of the housing, the exhaust gas flows from the rear to the front in addition to the top to bottom flow during the flow. Side grooves 1072 are provided on both side walls 1067 of the cooling fin 863, and both ends of the through groove 1064 communicate with a pair of side grooves 1072, respectively. The cooling tubes 865 pass through a pair of side slots 1072 to support the cooling fins 863 such that the cooling fins 863 are detachably connected to the cooling tubes 865.

The cooling fins of each layer are provided with a plurality of through grooves 1064, and the through grooves 1064 in at least a part of two adjacent cooling fins 863 are staggered, so that the exhaust gas does not pass through each cooling fin 863 along a straight line from top to bottom, but passes through each cooling fin along a curved path, and therefore heat exchange with the cooling pipes 865 and the cooling fins 863 can be better performed. In the example shown in fig. 10A and 10B, the through slots 1064 of the first and second layers of cooling fins 863 are arranged in a staggered manner, and the through slots 1064 of the third and fourth layers of cooling fins 863 are arranged in a staggered manner.

The number of cooling pipes 865 and side grooves 1072 is set corresponding to the number of through grooves 1064. And the cooling pipes 865 of each layer are in communication with the cooling medium inlet 855 and the cooling medium outlet 815 of the housing 701 so that compressed air as a cooling medium can flow into the cooling pipes 865 and out of the cooling pipes 865. As an example, the cooling tubes 865 of each tier are joined together by an inlet manifold 1081 and/or an outlet manifold 1085 (see also fig. 11), and then the inlet manifold 1081 and the outlet manifold 1085 are connected to the cooling medium inlet 855 and the cooling medium outlet 815 of the housing 701. The input manifold 1081 and the output manifold 1085 are tubes extending in the front-rear direction, and are closed at one end and connected at the other end to the cooling medium inlet 855 or the cooling medium outlet 815.

As an example, the respective cooling tubes of the first and fourth layers are connected together to form a right-side open U-shaped cooling tube, wherein the U-shaped cooling tube orifice of the first layer is connected to the output manifold 1085 and the U-shaped cooling tube orifice of the fourth layer is connected to the input manifold 1081. Similarly, the second and third layers of cooling tubes are connected together to form a left-side open U-shaped cooling tube, wherein the second layer of U-shaped cooling tube orifices are connected to the output manifold 1085 and the third layer of U-shaped cooling tube orifices are connected to the input manifold 1081. Thus, only two sets of the cooling medium inlet 855 and the cooling medium outlet 815 may be provided in the housing 701. In other embodiments, separate inlet and outlet manifolds may be provided at each end of each layer of cooling tubes to connect to the housing 701, where four sets of cooling medium inlets and cooling medium outlets are required.

In the example shown in this application, six cooling tubes are included in the first and fourth layers of cooling tubes 865, while five cooling tubes are included in the second and third layers.

Thereby, cooling tubes 865 can expand the area in heat exchange relationship with longitudinal gas flow 1068 through cooling fins 863 such that the temperature of longitudinal gas flow 1068 formed by the exhaust gas is reduced and a portion of the contaminants in the exhaust gas can condense into a liquid and flow up through channels 1064 to housing bottom 703.

The second stage cooling device 820 includes two cooling plates 817, each cooling plate 817 having the same structure as the cooling plates 317 in fig. 5 to form a vertical gas channel 1048. The cooling plate 817 has a cavity 1046.2 for containing a cooling medium (e.g., air), the cavity 1046.2 being in communication with an air inlet 716.1 and an air outlet 716.2 on the housing 701 so that air can flow into and out of the cooling plate 817 as cooling medium. Wherein a bottom transverse gas passage 1049.2 is formed between the right side cooling plate 817 and the bottom 703 of the housing and a top transverse gas passage 1049.1 is formed between the left side cooling plate 817 and the top 702 of the housing. The top lateral gas channels 1049.1 and the bottom lateral gas channels 1049.2 are in fluid communication with the vertical gas channels 1048 to form a curved gas cooling channel 1050. And the bottom transverse gas passage 1049.2 communicates with the first stage cooling device 810 to enable longitudinal gas flow 1068 in the first cooling capacity 861 from above and below through the first stage cooling device 810 into the gas cooling gallery 1050.

Returning to fig. 10A, as well, a filter member 836 is disposed in the middle of the filter volume 842 to divide the filter volume 842 into two sub-volumes, a lower sub-volume communicating with the divider lower opening 931 and an upper sub-volume communicating with the clean air outlet 731.2 and the divider upper opening 932. The impeller 1080 of the fan 724 is disposed in the upper subchamber such that the air intake side 1082 of the impeller 1080 of the fan 724 is in fluid communication with the upper subchamber. The air outlet side 1084 of the impeller 1080 of the fan 724 is in fluid communication with the clean air outlet 731.2 and the upper opening 932 of the divider plate. When impeller 1080 is rotated, gas can be caused to flow in cooling volume 841 and filtration volume 842 in the direction of the arrows shown in fig. 10A. As an example, the filter element 836 is also a steel ball filter screen.

It should be noted that the first stage cooling device 810 in this embodiment may be any fin type heat exchanger finished product known to those skilled in the art, so as to save cost.

Fig. 11 is a schematic perspective view of the cooling device in the exhaust gas purifying device 700 of the present application for illustrating the specific structure and positional relationship of the first stage cooling device 810, the second stage cooling device 820, the partition plate 937, and the coaming 827. Similar to the exhaust gas purifying apparatus 200, the top rear side of the right-side cooling plate 817 in the second-stage cooling apparatus 820 is provided with a stepped-shape catching groove for accommodating the coaming 827. Wherein the shroud 827 can form a connection channel 1135 with the housing 701, the connection channel 1135 having a self-cleaning gas outlet 1134 and a self-cleaning gas inlet 1114, wherein the self-cleaning gas outlet 1134 communicates with the upper opening 932 of the divider plate 937, and the self-cleaning gas inlet 1114 communicates with the exhaust gas inlet 711.1. In this embodiment, since the exhaust gas inlet 711.1 is located at a relatively close distance from the second stage cooling device 820, the shroud 827 is only required to be disposed at the rear side of the second stage cooling device 820, so that the self-cleaning gas inlet 1114 of the connection channel 1135 is in communication with the exhaust gas inlet 711.1.

Similarly, an adjustable baffle 1138 is also coupled to the divider plate 937 to adjust the size of the opening of the upper opening 932. This arrangement allows a portion of the gas in the subchamber in the upper portion of the filter volume 342 to exit the clean gas outlet 731.2 into the reflow oven and another portion of the gas to flow through the upper opening 932 into the connecting channel 1135 and through the connecting channel 1135 to near the exhaust gas inlet 711.1.

The cavity 1046.2 within the cooling plate 817 includes flow equalization plates 1156 each having a plurality of elongated holes 1158.

The exhaust gas is substantially purified in the exhaust gas purifying apparatus 700 as follows: the exhaust gas (temperature approximately 170 c) containing the contaminants is discharged from the high temperature zone of the reflow oven chamber and then enters the first cooling volume 861 through the exhaust gas inlet 711.1. The exhaust gas flows through the first stage cooling device 810 from top to bottom and back to front, and the compressed air is cooled to a gas temperature of about 110 to 130 c at the outlet by adjusting the speed of the compressed air flowing into and out of the cooling pipe 865, at which point the organic matters such as rosin in the exhaust gas are condensed from a gas state to a liquid state and flow from top to bottom through the through groove 1064 to the bottom 703 of the housing. The remainder of the exhaust gas flows from right to left through cooling plates 817 in secondary cooling device 820 by adjusting the rate at which air flows into and out of cooling plates 817 such that the remainder of the exhaust gas is cooled to a gas temperature at the outlet of approximately 60-80 c at which other contaminant organics in the exhaust gas, such as low condensation point acids or esters or ethers, condense from a gaseous state to a liquid state and flow along the side walls of cooling plates 817 to the bottom 703 of the housing. The remaining part of the exhaust gas flows into the filtering receptacle 842 through the lower opening 931 of the partition plate 937, then flows through the filtering part 836 from bottom to top, and is filtered by the filtering part 836 to remove particulate and mist organic matters therein, so as to obtain clean gas. Finally, most of the clean gas is discharged from the clean gas outlet 731.2 to the low temperature zone of the reflow oven furnace, the cleaning process of the exhaust gas is completed, and the remaining small portion of the clean gas flows back into the first stage cooling device 810 through the upper opening 932 and the connection channel 1135 to mix with the exhaust gas and reduce the temperature of the exhaust gas. Adjusting the opening size of the upper opening 932 may vary the amount of net gas that flows back into the first stage cooling device 810 through the upper opening 932 and the connecting channel 1135. Of course, the upper opening 932 may also be completely closed, preventing clean air from being able to flow back into the first stage cooling device 810 through the upper opening 932 and the connecting channel 1135. Wherein liquid contaminants at the bottom 703 of the housing are collected by a collection device 740.2.

The self-cleaning process of the exhaust gas purifying device 700 is similar to that of the exhaust gas purifying device 200, and will not be described again.

The main difference between the exhaust gas purification apparatus 200 and the exhaust gas purification apparatus 700 in the two embodiments of the present application is that the first stage cooling apparatus is different. Among them, the cooling plate 315 in the first stage cooling device 310 of the exhaust gas purifying device 200 has a smaller lateral area, thus allowing less contaminants to accumulate on the heat exchange member (cooling plate 315), and thus enabling longer maintenance intervals. While the first stage cooling device 810 of the exhaust gas purification device 700 is a commercially available finished piece, it can have a lower cost.

Although the present application will be described with reference to the specific embodiments shown in the drawings, it should be understood that many variations of the exhaust gas purification device of the present application are possible without departing from the spirit and scope and the background of the teachings of the present application. Those of ordinary skill in the art will also recognize that there are different ways to alter the arrangement of the embodiments disclosed herein, and are within the spirit and scope of the present application and the claims.

Claims

1. An exhaust gas purification device for purifying exhaust gas in a reflow oven hearth, characterized in that: the exhaust gas purification device (700) comprises:

A housing (701), wherein an exhaust gas inlet (711.1) and a clean gas outlet (731.2) are arranged on the housing (701); and

a first cooling device (810), a second cooling device (820), and a filter member (836) disposed within the housing (701), wherein the exhaust gas purification device (700) is configured such that gas entering the housing (701) from the exhaust gas inlet (711.1) flows through the first cooling device (810), the second cooling device (820), and the filter member (836) in that order and is discharged from the clean gas outlet (731.2);

wherein the first cooling device (810) comprises:

a plurality of cooling fins (863) arranged longitudinally, each of the plurality of cooling fins (863) being disposed transversely and each of the plurality of cooling fins (863) having a plurality of through slots (1064) therein such that gas can flow through the through slots (1064) to form a longitudinal gas flow (1068), and the plurality of cooling fins (863) being disposed with the through slots (1064) in at least a portion of adjacent two of the plurality of cooling fins (863) staggered; and

at least one cooling tube (865), each cooling tube (865) of the at least one cooling tube (865) having a cavity (1046.1) for receiving a cooling medium, the at least one cooling tube (865) being configured to traverse a side wall (1067) of at least one layer of the cooling fins (863) such that the cooling tube (865) is in heat exchange with the longitudinal gas flow (1068) via the cooling fins (863).

2. The exhaust gas purifying apparatus according to claim 1, characterized in that:

each layer of cooling fins (863) is arranged in a U shape, and the through grooves (1064) are arranged at the bottom (1066) of the cooling fins (863);

the at least one cooling tube (865) comprises several layers of cooling tubes (865), each layer of cooling tubes (865) traversing a side wall (1067) of one layer of cooling fins (863) in a lateral direction.

3. The exhaust gas purifying apparatus according to claim 2, characterized in that:

each layer of cooling fins (863) is provided with a side groove (1072) on the side wall, and the side groove (1072) is communicated with the through groove (1064), so that the cooling fins (863) can be detachably mounted on the cooling pipe (865) through the side groove (1072) and the through groove (1064).

4. The exhaust gas purifying apparatus according to claim 1, characterized in that:

the housing has a top (702) and a bottom (703);

the second cooling arrangement (820) comprises at least two cooling plates (817) arranged laterally, each cooling plate (817) of the at least two cooling plates (817) having a cavity (1046.2), the cavities (1046.2) being configured to accommodate a cooling medium, wherein each cooling plate (817) of the at least two cooling plates (817) is vertically disposed and spaced apart from an adjacent cooling plate to form a vertical gas channel (1048);

Wherein at least a part of the at least two cooling plates (817) are arranged as: each of which forms a bottom transverse gas channel (1049.2) with the bottom (703) of the housing or a top transverse gas channel (1049.1) with the top (702) of the housing, and wherein the bottom transverse gas channels (1049.2) and the top transverse gas channels (1049.1) are alternately arranged in the direction of arrangement of the at least two cooling plates (817);

wherein the bottom lateral gas channel (1049.2) and the top lateral gas channel (1049.1) are in fluid communication with the vertical gas channel (1048) to form a curved gas cooling channel (1050);

the longitudinal gas flow (1068) is in fluid communication with the gas cooling gallery (1050).

5. The exhaust gas purifying apparatus according to claim 1, characterized in that:

the exhaust gas purification device (700) further comprises a liquid collection device (740.2), the liquid collection device (740.2) being connected to the bottom (703) of the housing, the liquid collection device (740.2) being in fluid communication with the cooling plenum (841).

6. The exhaust gas purifying apparatus according to claim 4, wherein:

The housing is internally provided with a first cooling cavity (861), a second cooling cavity (862) and a filtering cavity (842), the waste gas inlet (711.1) is in fluid communication with the first cooling cavity (861), the purified gas outlet (731.2) is in fluid communication with the filtering cavity (842), the first cooling device (810) is arranged in the first cooling cavity (861), the second cooling device (820) is arranged in the second cooling cavity (862), and the filtering component (836) is arranged in the filtering cavity (842).

7. The exhaust gas purifying apparatus according to claim 6, wherein:

a connecting channel (1135) is arranged in the shell (701), and the connecting channel (1135) is in fluid communication with the first cooling cavity (861) and the filtering cavity (842), so that after the exhaust gas inlet (711.1) and the purified gas outlet (731.2) are closed, gas can circulate in the first cooling cavity (861), the second cooling cavity (862) and the filtering cavity (842).

8. The exhaust gas purifying apparatus according to claim 7, wherein:

the exhaust gas purification apparatus (700) further includes a shroud (827) provided in the housing (701);

wherein the connecting channel (1135) is formed by the housing (701) together with the shroud (827).

9. The exhaust gas purifying apparatus according to claim 8, wherein:

the housing (701) also has a rear portion (707), the enclosure (827) includes a cross plate (925) and a riser (926), the cross plate (925) abutting against the rear portion (707) of the housing, the riser (926) abutting against the top portion (702) of the housing such that the enclosure (827) and the housing (701) together form the connection channel (1135).

10. The exhaust gas purifying apparatus according to claim 7, wherein:

the exhaust gas purifying device (700) further comprises a partition plate (937), wherein the partition plate (937) is arranged between the cooling accommodating cavity (841) and the filtering accommodating cavity (842) and is used for separating the cooling accommodating cavity (841) and the filtering accommodating cavity (842);

wherein the partition plate (937) has an upper opening (932) and a lower opening (931), the lower opening (931) being located below the filter member (836) for communicating the cooling vessel (841) with the filter vessel (842), the upper opening (932) being located above the filter member (836) for communicating the filter vessel (842) with the connection channel (1135).

11. The exhaust gas purifying apparatus according to claim 10, characterized in that:

An adjustable baffle (1138) is arranged at the upper opening (932) to open or close the upper opening (932) or to adjust the opening size of the upper opening (932).

12. The exhaust gas purifying apparatus according to claim 4, wherein:

at least one flow equalizing plate (1156) is arranged in the cavity (1046.2) of the at least two cooling plates (817), the flow equalizing plate (1156) is arranged on a flow path of the cooling medium, and a plurality of through holes (1158) are uniformly arranged on the flow equalizing plate (1156) so that the cooling medium can pass through the through holes (1158) in the flowing process.

13. The exhaust gas purifying apparatus according to claim 10, characterized in that:

the exhaust gas purification device (700) further comprises a fan (724), the fan (724) is connected with the filtering cavity (842), wherein the fan (724) is provided with an air inlet side (1082) and an air outlet side (1084), the air inlet side (1082) is in fluid communication with the filtering cavity (842), and the air outlet side (1084) is in fluid communication with the clean gas outlet (731.2) and the upper opening (932).

14. The exhaust gas purifying apparatus according to claim 4, wherein:

the cavity (1046.1) of the cooling tube (865) is for receiving compressed air and the cavity (1046.2) of the cooling plate (817) is for receiving air.