CN101280943A - A device for long-term purification of compound pollution in indoor air - Google Patents

Abstract

The invention discloses a long-term device for purifying indoor air complex pollution, which mainly includes a high-voltage electrostatic discharge electrode, a dust collecting plate, a photocatalytic plate, an ultraviolet light source and a regeneration-free activated carbon fiber layer. The fan drives the airflow into the device, and the high-voltage electrostatic discharge electrode removes the particles in the airflow and generates a certain amount of ozone; the ultraviolet light source kills the microorganisms in the airflow, and generates a certain amount of ozone, photoelectrons, hydroxyl radicals, etc., and can stimulate TiO ₂ at the same time; The catalytic plate removes microorganisms and degrades chemical pollutants; the regeneration-free activated carbon fiber layer removes the remaining ozone and some unreacted pollutants in the airflow, and finally discharges clean air to achieve long-term purification of indoor air complex pollutants. The device of the invention can be used for compound polluted air treatment in closed or semi-closed human living spaces.

Description

A device for long-term purification of compound pollution in indoor air

technical field

The invention belongs to the technical field of indoor air treatment. The invention relates to a device for long-term purification of compound pollution in indoor air, especially a device for combined removal of compound pollution in indoor air by using static electricity-ozone-photocatalysis-maintenance-free activated carbon technology.

Background technique

On average, people spend more than 80% of their time indoors (closed spaces such as living rooms, offices, vehicles, shopping malls, hospitals, etc.), and with the modernization of production and lifestyles, especially the development of the information industry, people are more Most of the work and entertainment and sports activities can be carried out indoors, and the indoor activity time is even as high as more than 93%. The indoor air quality directly affects people's health. The main characteristics of indoor air pollution are: (1) The pollution components of indoor air pollution are complex; (2) The concentration of indoor air pollutants is relatively low, that is, it is very low compared with the emission concentration of industrial waste gas; (3) There are a large number of pollutants in indoor air. (4) The technical requirements for the purification of indoor air pollutants are no secondary pollution.

The usual indoor pollutants are roughly divided into three categories: the first category is organic and inorganic harmful gas pollutants, inorganic ones include carbon monoxide, carbon dioxide, nitrogen oxides, sulfur dioxide, hydrogen sulfide, ozone, radon, etc.; organic volatile organic compounds (VOC) include formaldehyde, benzene series, carbon tetrachloride, trichloroethylene, tetrachloroethylene, toluene diisocyanate (TDI) and so on. The second category is inhalable particulate matter, mainly dust, smoke, pollen and so on. The third category is microorganisms, mainly bacteria and viruses. Indoor air pollutants mainly come from human activities such as fuel combustion and smoking, volatilization of building decoration materials, and diffusion of outdoor pollutants.

For a wide variety of indoor pollutants, many treatment processes have been developed, and indoor air purification devices have been developed for some of these processes. For example: (1) Ventilation and ventilation device: use ventilation and ventilation facilities to realize the exchange of indoor and outdoor air. This technology is economical and convenient, but it only realizes the transfer of pollutants. At the same time, this technology increases the energy consumption of indoor heat preservation at the cost of consuming indoor temperature. (2) Pollutant adsorption device: mainly use resin, molecular sieve, silica gel, activated aluminum, zeolite, activated carbon and other adsorption materials to adsorb gaseous pollutants to achieve the purpose of removal. It is a commonly used and effective control technology for indoor air pollution control. The adsorption method can not destroy the components of the pollutants by adsorbing the pollutants. It transfers the pollutants from the air to the adsorbent, and can recover valuable raw materials while removing the pollutants. However, this method requires the regeneration of the adsorbent. , easy to cause secondary pollution. (3) Negative ion generating device: On the one hand, negative ions are easily adsorbed with tiny particles in the indoor air and become charged large ions to settle. On the other hand, they reverse the electrical poles of the bacterial protein surface and promote the death of bacteria. However, negative ion purification has high requirements on emission equipment, and the settled pollutants are prone to secondary flying, and the removal rate of low-concentration pollutants in some indoor air is not high, and by-products such as O ₃ and NO are produced. (4) Non-equilibrium plasma device: The highly reactive electrons, atoms, molecules and free radicals generated by gas discharge react with various organic and inorganic pollutant molecules, so that the pollutant molecules are decomposed into small molecular compounds. This technology can efficiently and conveniently destroy and decompose various pollutants, but it requires high power supply and has certain electromagnetic radiation. (5) Photocatalytic device: TiO ₂ photocatalytic oxidation technology is an environmentally friendly new technology, which can simultaneously remove various indoor air pollutants including inorganic substances, organic substances, microorganisms, etc., and has low energy consumption, easy operation, No secondary pollution and other advantages. However, due to the complex composition of indoor air, various indoor air purification devices are mainly aimed at one or several types of pollutants, and cannot effectively control compound pollution.

In order to solve the problem of indoor air compound pollution, people use a variety of purification technologies in combination. For example, the publication number is CN1451917A, and the Chinese patent titled "A Method and Device for Purifying Indoor Air" discloses a device for purifying indoor air, which uses a combination of filter dust removal-ultraviolet sterilization-photocatalytic sterilization and degradation of chemical pollutants method for indoor air treatment. However, ozone is easily generated under the ultraviolet lamp, causing secondary pollution, and the method and device do not mention avoidance measures. The publication number is CN2221175Y, and the Chinese patent titled "Composite Indoor Air Purifier" uses activated carbon adsorption-molecular sieve adsorption-catalytic oxidation method for air treatment, which can absorb and remove indoor air pollutants, and at the same time convert CO into CO ₂ exclusion, however, activated carbon adsorption and molecular sieve adsorption have the problem of adsorption saturation, and need to be replaced after long-term use or regenerated by certain methods, which cannot meet the requirements of long-term removal of indoor complex pollutants. It can be seen that, aiming at the present situation of indoor air pollution and its control, it is necessary to develop a device for long-term removal of indoor air compound pollution and apply it to people's lives.

Contents of the invention

The present invention aims at the disadvantages of current indoor air purifiers, such as not many types of pollutants, complex use process, inability to act efficiently for a long time, easy to produce secondary pollution, etc. Both have long-term purification devices with good removal effect.

A device for long-term purification of indoor air compound pollution, including a casing, the casing is equipped with a fan, a high-voltage electrostatic discharge electrode, a high-voltage power supply, a dust collection plate, a dust collector, a DC power supply, an ultraviolet light source, a photocatalytic plate, Regeneration-free activated carbon fiber layer, the lower end of the front part of the shell is provided with an air inlet, the lower end of the rear part is provided with an air outlet, and a fan is installed in the housing near the air outlet; a high-voltage electrostatic discharge electrode is installed in the housing near the air inlet, and the high-voltage electrostatic discharge electrode A dust collection plate is arranged in parallel; several groups of photocatalytic plates are arranged behind the dust collection plate, and one end of the adjacent photocatalytic plates is alternately fixed with the upper and lower plates of the shell, and there is a gap at the other end; an ultraviolet light source is arranged between the photocatalytic plates; There is a regeneration-free activated carbon fiber layer in front of the rear fan; the bottom of the device is equipped with a dust collector, a DC power supply, and a high-voltage power supply in sequence. The negative pole of the power supply is connected to the high-voltage electrostatic discharge electrode.

There are two dust-collecting plates, which are respectively arranged on both sides of the high-voltage electrostatic discharge electrode.

The high-voltage electrostatic discharge electrode adopts negative corona discharge, and the corona potential is any potential between negative 25 and negative 10KV.

The ultraviolet light source adopts a low-pressure mercury lamp, and the dominant wavelength is 200-300nm.

The photocatalytic plate is a metal plate such as titanium or stainless steel loaded with TiO ₂ , and its base material is connected to a DC power supply so that the potential of the plate is maintained at any potential between 1 and 2.5V.

The regeneration-free activated carbon fiber layer is an activated carbon fiber loaded with TiO ₂ on the surface and inside, wherein the mass content of TiO ₂ is between 5% and 30%.

After the indoor air enters the device from the air inlet through the fan, the purification process is mainly divided into four steps:

1. Electrostatic dust removal

The invention adopts the process of electrostatic dust removal to remove the particles in the air flow. Specifically, negative corona discharge dust removal is selected, and the corona potential is at any potential between negative 10 and negative 25KV.

This process can generate a certain amount of ozone, which enters the ultraviolet sterilization and photocatalysis section.

The reason for choosing negative corona discharge dust removal is: generally under the same operating conditions, the amount of ozone generated by the negative corona discharge electrostatic dust removal process is 10 times that of the positive corona discharge dust removal process. In order to achieve the requirements of efficient sterilization and degradation of organic matter in the present invention, the synergy of a certain amount of ozone is required. In addition, in terms of energy saving, the energy consumption of negative corona discharge is much lower than that of positive corona discharge.

2. Ultraviolet sterilization

The invention adopts the method of ultraviolet irradiation to remove microorganisms in the airflow. The light source is a low-pressure mercury lamp with a dominant wavelength of 200-300nm. Under the irradiation of ultraviolet light source, a certain amount of ozone, photoelectrons, hydroxyl radicals, etc. can be produced in the airflow.

3. TiO ₂ photocatalytic removal of chemical pollutants and some microorganisms

The invention adopts the _TiO2 photocatalysis method to remove chemical pollutants and some microorganisms in the airflow. Photocatalysis uses baffled channels to increase the gas-solid contact area. TiO ₂ is prepared on titanium plates by anodic oxidation or by chemical vapor deposition on titanium, stainless steel and other metal plates. The base material of the photocatalytic plate is connected with a DC power supply, and the potential is maintained at any potential between 1 and 2.5V, so as to promote the separation of photogenerated holes and electrons and improve the purification efficiency of the photocatalytic plate.

4. Regeneration-free activated carbon removes the remaining ozone and some unreacted pollutants in the airflow

The present invention adopts the active carbon fiber filter screen loaded with _TiO2 to remove the remaining ozone and some unreacted pollutants in the airflow, further reduces the concentration of pollutants, and ensures the purification efficiency. A certain amount of ozone is generated after the air flow passes through electrostatic dust removal and ultraviolet light source irradiation. Although most of it has been decomposed in the photocatalytic process, due to the fast air flow speed, some residual ozone and unreacted chemical pollutants are still brought out. Load The activated carbon fiber filter of _TiO2 absorbs it and degrades it. In addition, since the surface of the activated carbon fiber filter is loaded with TiO ₂ , its adsorbed pollutants can be degraded by photocatalysis, so that it can maintain a certain adsorption capacity and can be used for a long time without heat treatment for regeneration.

The device of the invention can be used for compound polluted air treatment in closed or semi-closed human living spaces (such as living rooms, offices, conference rooms, laboratories, toilets, wards, and passenger cars).

The device of the present invention has the advantages of: it can remove compound pollutants such as particulate matter, biological pollutants, and chemical pollutants in the indoor air, and has a wide range of applications; it uses regeneration-free activated carbon to remove the remaining ozone and some unreacted pollutants in the airflow, avoiding Secondary pollution is avoided, and regeneration-free activated carbon does not require frequent replacement and maintenance, which reduces treatment costs, is simple to operate, and has a long service life; the gas path adopts a catalytic plate baffle method, which reduces wind resistance, increases the length of the flow channel, and has high catalytic efficiency.

Description of drawings

Fig. 1 is the schematic diagram of the cross-sectional structure of the assembly state of the best embodiment of the device of the present invention

Among them: 1 dust collection plate, 2 shell, 3 high-voltage electrostatic discharge electrode, 4 air inlet, 5 dust collector, 6 photocatalytic plate, 7 regeneration-free activated carbon fiber layer, 8 air outlet, 9 fan, 10 high-voltage power supply, 11 DC power supply, 12 UV light source.

Detailed ways

A best implementation mode of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Fig. 1, a kind of long-acting device for purifying indoor air complex pollution comprises casing 2, and casing 2 is provided with blower fan 9, high-voltage electrostatic discharge electrode 3, high-voltage power supply 10, dust collection plate 1, dust collector 5, direct current Power supply 11, ultraviolet light source 12, photocatalytic plate 6, regeneration-free activated carbon fiber layer 7. The lower end of the front part of the shell 2 is provided with an air inlet 4, and the lower end of the rear part is provided with an air outlet 8, and a fan 9 is arranged in the housing near the air outlet 4; a high-voltage electrostatic discharge electrode 3 is arranged in the housing near the air inlet 4, and the high-voltage electrostatic discharge electrode 3 There are two dust-collecting plates 1 on both sides; several groups of photocatalytic plates 6 are arranged behind the dust-collecting plates 1, and one end of the adjacent photocatalytic plates 6 is alternately fixed with the upper and lower plates of the shell 2, and there is a gap at the other end; the photocatalytic An ultraviolet light source 12 is arranged between the boards 6; a dust collector 5, a DC power supply 11, and a high-voltage power supply 10 are arranged in turn at the bottom of the device, wherein the dust collector 5 is placed in the middle of the bottom of the two dust collecting boards 1, and the positive pole of the DC power supply 11 is connected to the photocatalytic board 6, and the negative pole of the high-voltage power supply 10 is connected with the high-voltage electrostatic discharge electrode 3.

The fan 9 drives the airflow, and the airflow enters the purification device through the air inlet 4, removes particulate matter under the action of the high-voltage electrostatic discharge electrode 3 and the high-voltage power supply 10, and generates a certain amount of ozone. The corona potential is between negative 25 and negative 10KV any potential. Particles are collected by the dust collecting plate 1 and fall into the dust collector 5, and the dust collector 5 is an adhesive material, which can be taken out and cleaned regularly. The photocatalytic plate 6 can be made on the metal substrate by anodic oxidation or chemical vapor deposition, and the metal substrate is provided with a positive potential of 0-2.5V by the DC power supply 11 . The photocatalytic plate 6 constitutes a folded flow channel, and the airflow passes through the flow channel to remove microorganisms under the irradiation of an ultraviolet light source 12 (using a low-pressure mercury lamp, with a dominant wavelength of 200-300nm). The ultraviolet light irradiates the photocatalytic plate 6, and the airflow passes through the photocatalysis to remove pollutants such as VOCs and consume a certain amount of ozone. The air flow passes through the regeneration-free activated carbon fiber layer 7 to absorb and remove the remaining ozone and pollutants, and then it is discharged from the air outlet 8. The regeneration-free activated carbon fiber layer 7 is an activated carbon fiber with _TiO2 loaded on the surface and inside, and the mass content of _TiO2 is between 5 and 2. Between 30%.

Embodiment 1: The structure of the device is shown in Figure 1. The total power consumption of the whole machine is 60W, the processing air volume is 1m ³ /min, the corona potential is negative 25KV, the metal substrate of the photocatalytic plate is provided with a positive potential of 0.3V by a voltage DC power supply, and the TiO ₂ in the regeneration-free activated carbon fiber layer The mass content is 15%. Degrade toluene and formaldehyde in a 30m ³ closed environment cabin, the temperature in the cabin is 28°C, the relative humidity is 55%, the toluene concentration is 12mg/m ³ , the formaldehyde concentration is 30mg/m ³ , and the toluene concentration is 0.56mg after 12 hours of starting up /m ³ , the concentration of formaldehyde was 0.25mg/m ³ , and no ozone was detected. The removal rate of toluene is 95.3%, and the removal rate of formaldehyde is 99.1%.

Embodiment 2: The structure of the device is shown in Figure 1. The total power consumption of the whole machine is 60W, the processing air volume is 1m ³ /min, the corona potential is negative 10KV, the metal substrate of the photocatalytic plate is provided with a positive potential of 0.6V by a DC power supply, and the mass of TiO ₂ in the regeneration-free activated carbon fiber layer The content is 5%. Running in a 60m ³ living room, the indoor temperature is 25°C, the relative humidity is 50%, the PM ₁₀ concentration is 0.9mg/m ³ , the toluene concentration is 1.3mg/m ³ , the formaldehyde concentration is 5.0mg/m ³ , the total number of colonies 3600cfu/m ³ , 12 hours after starting up, the concentration of PM ₁₀ is 0.02mg/m ³ , the concentration of toluene is 0.11mg/m ³ , the concentration of formaldehyde is 0.08mg/m ³ , the total number of colonies is 900cfu/m ³ , and ozone is not detected . The PM ₁₀ removal rate was 97.7%, the toluene removal rate was 91.5%, the formaldehyde removal rate was 98.4%, and the colony removal rate was 75.0%.

Embodiment 3: The structure of the device is shown in Figure 1. The total power consumption of the whole machine is 80W, the processing air volume is 1m ³ /min, the corona potential is negative 10KV, the metal substrate of the photocatalytic plate is provided with a positive potential of 0.8V by a DC power supply, and the mass of TiO ₂ in the regeneration-free activated carbon fiber layer The content is 5%. Running in a 45m ³ hospital toilet, the indoor temperature is 30°C, the relative humidity is 68%, the PM ₁₀ concentration is 0.03mg/m ³ , the total number of colonies is 7200cfu/m ³ , and after 12 hours of starting up, the PM ₁₀ concentration is 0.01g/m 3 m ³ , the total number of bacterial colonies was 1600cfu/m ³ , and ozone was not detected. The PM ₁₀ removal rate was 66.7%, and the colony removal rate was 77.8%.

Embodiment 4: The structure of the device is shown in Figure 1. The total power consumption of the whole machine is 30W, the processing air volume is 0.50m ³ /min, the corona potential is negative 15KV, the metal substrate of the photocatalytic plate is provided with a positive potential of 2.5V by a DC power supply, and the TiO ₂ in the regeneration-free activated carbon fiber layer The mass content is 25%. Running in a 32-seat air-conditioned coach, the temperature inside the car is 25°C, the relative humidity is 50%, the concentration of PM ₁₀ is 0.06mg/m ³ , the concentration of toluene is 1.2mg/m ³ , and the concentration of formaldehyde is 2.3mg/m ³ . The total number of colonies is 2200cfu/m ³ . After 12 hours of starting up, the concentration of PM ₁₀ is 0.02mg/m ³ , the concentration of toluene is 0.13mg/m ³ , the concentration of formaldehyde is 0.09mg/m ³ , the total number of colonies is 850cfu/m ³ , and the ozone is not Check out. The PM ₁₀ removal rate was 66.7%, the toluene removal rate was 89.2%, the formaldehyde removal rate was 99.6%, and the bacterial colony removal rate was 61.4%.

Claims (5)

1, a kind of device of long-acting purifying indoor air combined pollution, comprise shell (2), it is characterized in that: be provided with blower fan (9), high-pressure electrostatic discharge electrode (3), high voltage source (10), collecting plate (1), dust-collector (5), dc source (11), ultraviolet source (12), photocatalysis plate (6) in the described shell (2), exempt from regenerated carbon fibrage (7); Shell (2) front lower ends is provided with air inlet (4), and the lower end, rear portion is provided with gas outlet (8), near gas outlet (8) blower fan (9) is set in the housing; Be provided with high-pressure electrostatic discharge electrode (3), the parallel collecting plate (1) that is provided with near air inlet (4) in the housing with high-pressure electrostatic discharge electrode (3); Some groups of photocatalysis plates (6) are set behind the collecting plate (1), and adjacent photocatalysis plate (6) one ends are alternately fixed with the upper and lower plates of shell (2), and the other end leaves the space; Be provided with ultraviolet source (12) between photocatalysis plate (6); Preceding being provided with of housing rear portion blower fan (9) exempted from regenerated carbon fibrage (7); Bottom of device is established dust-collector (5), dc source (11), high voltage source (10) successively, wherein dust-collector (5) places in the middle of collecting plate (1) below, dc source (11) is anodal to link to each other with photocatalysis plate (6), and high voltage source (10) negative pole links to each other with high-pressure electrostatic discharge electrode (3).

2, the long-acting purifier of room air combined pollution as claimed in claim 1, it is characterized in that: described collecting plate is two, sets up high-pressure electrostatic discharge electrode (3) both sides separately.

3, the long-acting purifier of room air combined pollution as claimed in claim 1 is characterized in that: described ultraviolet source (12) adopts low pressure mercury lamp, dominant wavelength 200～300nm.

4, the long-acting purifier of room air combined pollution as claimed in claim 1 is characterized in that: described photocatalysis plate (6) has TiO for load ₂Sheet metal.

5, the long-acting purifier of room air combined pollution as claimed in claim 1 is characterized in that: the described regenerated carbon fibrage (7) of exempting from has TiO for the equal load in surface and inside ₂NACF, TiO ₂Mass content be 5～30%.