摘要:
A multi-filter PM 10-PM 2.5 sampler which enable the simultaneous collection of four PM 10 and four PM 2.5 samples is disclosed. The sampler is provided with a PM 10 impactor to remove coarse particles and operates at 33.4 L/min. After the PM 10 impactor, the aerosol flow is divided by half by a branch pipe. Half of the flow is directed into four PM 10 cassettes, while the other half is directed into four PM 2.5 cassettes after the aerosols are further classified by a PM 2.5 impactor. To ensure the aerosol flow uniformly passes through each of the four PM 10 or four PM 2.5 cassettes, an orifice plate is assembled behind each of the filter cassettes to increase the pressure drop, such that the flow rates of eight sampling lines are nearly equal.
摘要:
A personal nanoparticle sampler is disclosed to include a pre-classifier, a nozzle, a connector and a final filter pack. The connector and the final filter pack respectively accommodate a particle-sizing filter and a final filter to collect nanoparticles smaller than a diameter. The pre-classifier removes large particles to avoid clogging of the connector. The nozzle raises the airflow velocity to reduce the cut-off diameter of the particle-sizing filter without increasing the total flowrate, allowing the personal nanoparticle sampler to be used with a personal sampling pump.
摘要:
A wet electrostatic precipitator (ESP) is disclosed to have a housing, several discharge wires, two roughened collection electrodes coated with TiO2 or SiO2 nanoparticles, two porous metallic plates, and two roughened glass plates coated with TiO2 or SiO2 nanoparticles. The porous metallic plates and the glass plates coated with TiO2 or SiO2 nanoparticles located above the collection electrodes are used to enhance the uniformity of the water film. When particles are introduced into the ESP, they are charged by gas ions generated by corona discharge, and then migrate to collection electrodes due to electrostatic force. Finally, particles are removed by uniform water film flowing downward along the collection electrodes. Furthermore, pulse jet passing through the small holes on the collection plates is used to clean discharge wires, maintaining electric corona strength and prolonging the operation life.
摘要:
A three-stage dust sampler makes use of a porous foam as the impactor substrates. The sampler includes an annular inlet which conforms to ISO/CEN/ACGIH inhalable sampling criteria, two impactor stages to classify thoracic and respirable particles and a final filter to collect respirable particles after the impactors. For 100 ppi polymer foam substrates, and a flow rate of 3.2 lpm, the collection efficiency curves of the thoracic and respirable dust matches ISO/CEN/ACGIH criteria when the jet-to-plate distance is 1.0. The cut-off aerodynamic diameter is 9.6 and 4.0 μm for the first and second impactor stages, respectively, and √{square root over (stk50)} is 0.39 for both stages. The collection efficiencies for solid particles is equal to that for liquid particles, indicating that there is no solid particle bouncing from the foam substrates.
摘要:
A purging air flow system that causes air to pass over a pyrometer lens or window to keep it clean and free from particulate contaminants has an annular, continuous slot for air inlet around the periphery of the lens to permit flow of air across the lens without any obstructions in the path of flow inwardly from the outer edge of the lens. An asymmetric flow pattern is established across the lens surface, either by having a differential size slot at different peripheral portions of the peripheral edge of the lens or window, or by providing a radial swirl about the axis of the window so that when the air goes through the slot, the tangential velocity creates a moving asymmetric flow pattern on the window surface.
摘要:
A multi-filter PM 10-PM 2.5 sampler which enable the simultaneous collection of four PM 10 and four PM 2.5 samples is disclosed. The sampler is provided with a PM 10 impactor to remove coarse particles and operates at 33.4 L/min. After the PM 10 impactor, the aerosol flow is divided by half by a branch pipe. Half of the flow is directed into four PM 10 cassettes, while the other half is directed into four PM 2.5 cassettes after the aerosols are further classified by a PM 2.5 impactor. To ensure the aerosol flow uniformly passes through each of the four PM 10 or four PM 2.5 cassettes, an orifice plate is assembled behind each of the filter cassettes to increase the pressure drop, such that the flow rates of eight sampling lines are nearly equal.
摘要:
A venturi scrubber which avoids clogging in the throat by dust particles is developed. The scrubber includes a venturi tube, two scrubbing fluid conduits and a storage tank. The venturi tube has a converging section, a diverging section and a throat section which is connected between the converging section and the diverging section. The scrubbing fluid conduit has a top end connected with the bottom end of the converging section of the venturi tube, and a bottom end extending into the storage tank. Thereby, scrubbing fluid can be guided directly into the storage tank without passing through the throat section. As a result, the clogging of dust particles on the converging section of the venturi throat can be minimized and the abnormal increase in the pressure drop of the air flow through the throat can also be avoided.
摘要:
A venturi scrubber which avoids clogging in the throat by dust particles is developed. The scrubber includes a venturi tube, two scrubbing fluid conduits and a storage tank. The venturi tube has a converging section, a diverging section and a throat section which is connected between the converging section and the diverging section. The scrubbing fluid conduit has a top end connected with the bottom end of the converging section of the venturi tube, and a bottom end extending into the storage tank. Thereby, scrubbing fluid can be guided directly into the storage tank without passing through the throat section. As a result, the clogging of dust particles on the converging section of the venturi throat can be minimized and the abnormal increase in the pressure drop of the air flow through the throat can also be avoided.
摘要:
A wet electrostatic precipitator is disclosed to include a condensation-growth chamber, a precipitation chamber connecting with the condensation-growth chamber, three dual-sleeve members mounted in the precipitation chamber, three discharge electrodes connecting with the dual-sleeve members, two insulating members covering on the inner surface of the precipitation chamber, and two ground electrodes mounted on the outside of the precipitation chamber. Thus, a uniform water film is formed on the surface of the insulating members to wash away the particles from waste gas. The condensation-growth chamber is provided for the particles to grow therein and thereby enhances the collection efficiency. The insulating member acts as a shield between the discharge electrodes and the ground electrodes and thereby avoids a short circuit or sparks.
摘要:
A personal nanoparticle sampler is disclosed to include a pre-classifier, a nozzle, a particle-sizing filter pack and a final filter pack. The particle-sizing filter pack and the final filter pack respectively accommodate a particle-sizing filter and a final filter to collect nanoparticles smaller than a diameter. The pre-classifier removes large particles to avoid clogging of the particle-sizing filter pack. The nozzle raises the airflow velocity to reduce the cut-off diameter of the particle-sizing filter without increasing the total flowrate, allowing the personal nanoparticle sampler to be used with a personal sampling pump.