CN105201598A - Wet-process purification device for motor vehicle tail gas - Google Patents

Abstract

The invention provides a wet purification device for motor vehicle tail gas. It includes a gas collection hood, the gas collection hood has a connected intake pipe and a pressure stabilizing chamber, an exhaust gas resistance stabilizing plate is arranged in the pressure stabilizing chamber, and the exhaust gas damping stabilizing plate is a hemispherical surface, and The outer side of the hemispherical surface faces the air intake pipe, and the automobile exhaust gas is directly sprayed onto the exhaust air resistance stabilizing plate in the gas collecting hood; the conveying pipe, one end of the conveying pipe and the side of the stabilizing chamber away from the air intake pipe The other end communicates with the treatment tank and passes into the treatment liquid; the air pump is connected with the delivery pipeline, and is used to deliver the motor vehicle exhaust gas in the delivery pipeline to the treatment tank. The motor vehicle tail gas wet purification device provided by the invention collects the tail gas discharged from the motor vehicle for wet purification treatment, reduces the content of nitrogen oxides in the air, and has low manufacturing cost.

Description

Motor vehicle exhaust wet purification device

technical field

The invention relates to a wet purification device for motor vehicle tail gas, which belongs to the technical field of environmental engineering.

Background technique

While industrial civilization and urban development have created enormous wealth for human beings, they have also discharged billions of tons of waste gas and waste into the air, turning the air circle on which human beings depend for survival into a repository of garbage and poisonous gas in the air. Nowadays, smoggy weather due to air pollution has become an inescapable problem in the lives of urban residents. Many chimneys, frequent motor vehicles and sudden reduction of green space are the main reasons for the formation of smog weather, especially the exhaust emissions of a large number of motor vehicles in urban areas, causing serious air pollution in urban areas.

Gasoline as a motor vehicle fuel is mainly composed of carbon and hydrogen. When gasoline is normally burned, it produces carbon dioxide and water vapor. However, because gasoline usually contains other impurities and additives, and often cannot be completely burned, some harmful substances are often discharged. Studies have shown that the main pollutants in motor vehicle exhaust include carbon monoxide, hydrocarbons and nitrogen oxides (such as nitric oxide, nitrogen dioxide) and so on. Among them, nitrogen oxides can damage people's vision and respiratory system, and form photochemical smog, which is the main substance that produces acid rain, and can turn plants from green to brown until they die on a large scale. More importantly, polluted gases form a temperature inversion layer about 800 meters above the city, shielding the entire city, hindering the emission of polluted gases and air convection, which is the main cause of persistent urban smog.

It can be seen that reducing motor vehicle exhaust is of great significance for improving the environment and improving people's quality of life. Many motor vehicles are equipped with exhaust gas purification devices, such as three-way catalytic converters, for this reason. Generally, a three-way catalytic converter is composed of a housing 1, a damping layer 2, a carrier 3 and a coating. As shown in Figure 1, the housing 1 has a cylindrical cavity made of a double-layer stainless steel sheet. The shock-absorbing layer 2 is set in the interlayer, and the carrier 3 is installed in the cylindrical cavity. The carrier 3 is generally made of ceramics. Its shape is a mesh partition, and it can also be spherical or prismatic. layer, which contains noble metal catalysts, such as platinum, rhodium, palladium, etc., that can purify motor vehicle exhaust. However, because the above-mentioned three-way catalytic converter uses noble metals as catalysts, the manufacturing cost is relatively high, which is not conducive to popularization and regular replacement. In addition, the service life of the three-way catalyst is usually 80,000 to 100,000 kilometers, and the air purification effect will be greatly reduced if it is not replaced in time due to cost issues. For example, there are currently 5.7 million private cars in Beijing, but due to the failure of the three-way catalyst used in them, it is actually equivalent to the emission of 15 million motor vehicles, seriously affecting the air quality in Beijing's urban area.

Contents of the invention

The invention provides a motor vehicle tail gas wet purification device, which performs wet purification treatment on the tail gas discharged by the motor vehicle, reduces the content of nitrogen oxides in the air, and has low manufacturing cost.

In order to achieve the above object, the present invention provides a wet purification device for motor vehicle exhaust, comprising a gas collecting hood, the gas collecting hood has an air intake pipe and a pressure stabilizing chamber which are connected, and in the said stabilizing chamber A tail gas air resistance stabilizing plate is provided, and the tail gas air resistance stabilizing plate is a hemispherical surface, and the outside of the hemispherical surface faces the intake pipe; a treatment tank is equipped with a treatment liquid;

A delivery pipeline, one end of the delivery pipeline communicates with the side of the pressure stabilizing chamber away from the inlet pipeline, and the other end communicates with the treatment tank and passes into the treatment liquid;

An air pump, the air pump is connected to the delivery pipeline, and is used to deliver the motor vehicle exhaust in the delivery pipeline to the treatment tank.

Further, the end of the inner wall of the intake pipe away from the plenum chamber is provided with a baffle sheet, and the air baffle sheet forms an angle with the inner wall of the air intake pipe and slopes toward the plenum chamber.

Further, the treatment liquid is water or urea aqueous solution.

Further, the treatment liquid is an alkaline aqueous solution.

Further, the inner wall of the treatment box is made of plastic or metal, such as stainless steel.

Further, the inner wall of the delivery pipe has rifling.

Further, the air pump is connected with a controller capable of adjusting the pressure of the air pump according to the running speed of the motor vehicle, so that the pressure of the air pump is negatively correlated with the running speed of the motor vehicle.

Further, a safety valve is provided at the interface between the delivery pipeline and the treatment tank, and the safety valve is opened when the air pump is working and closed when the air pump is stopped.

Further, the processing tank is equipped with a processing liquid concentration sensor, which will give an alarm when the processing liquid fails

The motor vehicle exhaust wet purification device provided by the present invention can reduce the content of nitrogen oxides emitted by motor vehicles in the air, thereby reducing the pollution of motor vehicle exhaust to the air and the harm to the human body. The liquid is used for wet purification of automobile exhaust gas, so that the cost of the exhaust gas purification device is relatively low.

Description of drawings

Fig. 1 is a structural schematic diagram of an existing three-way catalytic converter.

Fig. 2 is a schematic structural diagram of a wet purification device for motor vehicle exhaust provided by an embodiment of the present invention.

Detailed ways

The present invention is described more fully below with reference to the accompanying drawings that illustrate embodiments of the invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

As shown in Figure 2, an embodiment of the present invention provides a wet purification device for motor vehicle exhaust, including:

The gas collecting hood 10, the air intake pipe 11 and the pressure stabilizing chamber 12 connected by the gas collecting hood 10 are provided with an exhaust gas resistance stabilizing plate 14 in the described air intake duct, and the exhaust gas damping stabilizing plate 14 is A hemispherical surface, and the outer side of the hemispherical surface faces the intake pipe 11; a treatment box 40 is equipped with a treatment liquid, and the treatment box 40 is used to purify the tail gas;

A delivery pipeline 30, one end of the delivery pipeline 30 communicates with the side of the pressure stabilizing chamber 12 away from the intake pipeline 11, and the other end communicates with the treatment tank 40 and passes into the treatment liquid;

An air pump 20 , the air pump 20 is arranged in the delivery pipeline 30 , and is used to deliver the motor vehicle exhaust in the delivery pipeline 30 to the treatment tank 40 . The pressure stabilizing chamber 12 in this embodiment may be spherical, hemispherical or cylindrical, etc., and its inner diameter may be larger than the inner diameter of the intake pipe 11 communicating with it.

Further, the end of the inner wall of the intake pipe far away from the pressure stabilizing chamber can also be provided with a gas blocking sheet 13 , and the air blocking sheet 13 forms an angle with the inner wall of the intake pipe 11 and is inclined toward the direction of the stabilizing chamber 12 . The air blocking sheet 13 is arranged on the inner wall of the air inlet passage 11, which can be several sheets of split type, preferably evenly distributed on the inner wall of the air inlet passage 11 away from the end of the pressure stabilizing chamber 12, and there is a gap between the opposite air blocking sheets 13. spaced so that the motor vehicle exhaust pipe 4 can be inserted into the intake passage 11.

As shown in Figure 2, when the motor vehicle exhaust wet purification device provided by this embodiment is in use, the exhaust pipe 4 of the motor vehicle engine 5 is inserted into the air intake passage 11, so that the exhaust pipe 4 is located at the opposite air barrier sheet 13, and has a set distance from the pressure-stabilizing chamber 12. In the process of absorbing exhaust gas, the wind pressure generated during the running of the vehicle is used as the first absorption power, so that the exhaust gas enters the intake passage 11 and is sprayed onto the exhaust gas damper plate 14, and the exhaust gas enters the stabilizer plate 14 with a larger inner diameter. Pressure chamber 12, to reduce the impact of the device on the air resistance of the engine, which is conducive to the normal exhaust exhaust of the motor vehicle, the setting of the air blocking sheet 13 can effectively prevent the exhaust gas from escaping, thereby ensuring the absorption effect; Under the action of 20, a negative pressure is generated in the delivery pipeline 30, which, as the second absorption power, sucks the exhaust gas inside the pressure stabilizing chamber 12 into the delivery pipeline 30, and finally enters the treatment box for purification.

The motor vehicle tail gas wet purification device provided by the invention can collect and purify the tail gas emitted by the motor vehicle before it diffuses in a wide range, and can effectively remove fine dust and nitrogen oxides in the motor vehicle tail gas, while not The air resistance of the output pipeline of the automobile engine is changed, and the structure is simple and the manufacturing cost is low.

The processing box 40 is provided with an exhaust port 41 communicating with the outside, for discharging the purified gas into the air; and is also provided with a liquid discharge port 42 and a liquid inlet port 43 for discharging and filling the processing liquid. The processing box 40 can be arranged in the trunk of a motor vehicle, for example, and communicate with the gas collecting hood 10 through the delivery pipe 30 . The volume of the treatment liquid in the treatment tank 40 can be determined according to the amount of exhaust gas discharged by the motor vehicle per unit time and the content of nitrogen oxides in the exhaust gas, so as to effectively purify the polluted gas and make the gas discharged from the treatment tank meet the requirements of the relevant national environmental protection standards. The regulations shall prevail, usually around 1-10L.

The air pump 20 is arranged in the delivery pipeline 30, and the exhaust gas is transported to the treatment box 40 for purification treatment, thereby reducing the pollution of the air and the harm to human health caused by the exhaust gas emitted by motor vehicles.

The treatment liquid may be water, or an alkaline aqueous solution. For example, the treatment liquid is an aqueous solution of NaOH or KOH. The treatment fluid can absorb nitrogen oxides (such as NO and NO ₂ ) in motor vehicle exhaust and convert them into HNO ₃ . When alkaline aqueous solution is used as the treatment liquid, the generated _HNO3 can be converted into neutral nitrate at the same time.

The treatment liquid can also be an aqueous urea solution, which produces ammonia gas with a reducing effect. According to the following formula 1, the ammonia gas reacts with NO _x in the exhaust gas of motor vehicles and is converted into harmless water and N ₂ , while absorbing Harmful smoke particles. When urea aqueous solution is used as the treatment liquid, the urea concentration can generally be between 15-50 wt%, so as to achieve a good purification effect.

NH ₃ +NO _x →H ₂ O+N ₂ ...Formula 1

The above-mentioned treatment solution should be replaced regularly, and whether the treatment solution has expired can be judged by detecting the concentration of urea and other substances in the treatment solution or the pH of the treatment solution. Specifically, the treatment liquid can be connected to the treatment liquid failure alarm 80, and when the treatment liquid failure alarm 80 detects that the treatment liquid is invalid, an alarm is issued. Or the processing tank 40 is equipped with a processing liquid concentration sensor, which will alarm when the processing liquid fails. The exhausted treatment liquid is discharged through the liquid outlet 42 and refilled from the liquid inlet 43 .

The inner wall of the treatment box 40 can be made of plastic, and the inner wall of the treatment box made of plastic can effectively avoid acid and alkali corrosion and prolong the service life of the treatment box. In addition, the inner wall material of the treatment box 40 can also be made of inert metal or ceramics, etc., or an acid-resistant or alkali-resistant coating can be applied on the metal surface, so as to prevent the inner wall of the treatment box from being corroded by acid and alkali, thereby prolonging the service life of the treatment box. .

The inner wall of the conveying pipe 30 may have rifling. The rifling is a line that presents a helical protrusion along the axial direction of the conveying pipe, and the inner wall of the conveying pipe 30 is provided with a rifling that facilitates the motor vehicle exhaust gas entering it to enter the treatment box at a faster speed under the action of the air pump 20 to carry out Treating and discharging is beneficial to further reducing the influence of the motor vehicle exhaust wet purification device on the air resistance of the engine.

The air pump 20 may be connected with a controller 60 capable of adjusting the pressure of the air pump 20 according to the vehicle speed, so that the pressure of the air pump 20 is negatively correlated with the vehicle speed. Specifically, the controller 60 can obtain the driving speed of the motor vehicle, and adjust the pressure of the air pump 20 according to the speed. Work at a lower rotational speed. When the engine is in an idle state, the exhaust emission is relatively large. At this time, the air pump 20 can be adjusted to work at a higher rotational speed.

A safety valve may be provided at the interface between the delivery pipeline 30 and the treatment tank 40, and the safety valve is opened when the air pump 20 is working and closed when the air pump 20 is stopped. Specifically, the safety valve can be an electromagnetic valve, which is connected with a valve controller capable of obtaining the working state of the air pump 20, so that the safety valve is opened when the air pump 20 is working and closed when the air pump 20 stops, and the safety valve can prevent the engine from cooling down. Afterwards, and when the air pump 20 stops, the treatment liquid is sucked back into the air pump 20.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (9)

1. a motor-vehicle tail-gas Wet purifier, is characterized in that, comprising:

Gas skirt, described gas skirt has the admission line and voltage stabilizing chamber that are connected, and described pressure stabilizing cavity indoor are provided with tail gas vapour lock stabilier, and described tail gas vapour lock stabilier is semi-sphere, and described hemispherical outside is towards described admission line;

The treatment box for the treatment of fluid is housed;

Conveyance conduit, one end of described conveyance conduit is communicated with the side of described voltage stabilizing chamber away from described admission line, and the other end is communicated with described treatment box and passes in described treatment fluid;

Air pump, described air pump is connected with described conveyance conduit, for the described motor-vehicle tail-gas in conveyance conduit is delivered to described treatment box.

2. motor-vehicle tail-gas Wet purifier according to claim 1, it is characterized in that, described admission line inwall is provided with gas barrier plate away from one end of described voltage stabilizing chamber, and described gas barrier plate and the described admission line inwall direction at angle and to described voltage stabilizing chamber tilts.

3. motor-vehicle tail-gas Wet purifier according to claim 1, is characterized in that, described treatment fluid is water or aqueous solution of urea.

4. motor-vehicle tail-gas Wet purifier according to claim 1, is characterized in that, described treatment fluid is alkaline aqueous solution.

5. motor-vehicle tail-gas Wet purifier according to claim 1, is characterized in that, the inwall material of described treatment box is plastics or metallic material.

6. motor-vehicle tail-gas Wet purifier according to claim 1, is characterized in that, the inwall of described conveyance conduit has rifling.

7. motor-vehicle tail-gas Wet purifier according to claim 1, is characterized in that, described air pump is connected with the controller that can adjust air pump pressure according to vehicle running speed, to make described air pump pressure and vehicle running speed negative correlation.

8. the motor-vehicle tail-gas Wet purifier according to any one of claim 1-7, is characterized in that, the jointing of described conveyance conduit and described treatment box is provided with Safety valve, and described Safety valve is opened when air pump works, and closes when air pump stops.

9. the motor-vehicle tail-gas Wet purifier according to any one of claim 1-7, is characterized in that, described treatment box is equipped with treatment fluid concentration sensor, treatment fluid inefficacy alarm.