A system for removing dust from air (101) includes a dust removal system inlet (1011), a dust removal system outlet, and an electric field apparatus (1014). The electric field apparatus (1014) has an electric field apparatus inlet (3085), an electric field apparatus outlet (3088), a dust removal electric field cathode (3081) and a dust removal electric field anode (3082). The dust removal electric field cathode (3081) and the dust removal electric field anode (3082) are used to generate an ionization dust removal electric field. By means of the present system for removing dust from air (101), particulate matter can be effectively removed from air.

A system for removing dust from air (101) includes a dust removal system inlet (1011), a dust removal system outlet, and an electric field apparatus (1014). The electric field apparatus (1014) has an electric field apparatus inlet (3085), an electric field apparatus outlet (3088), a dust removal electric field cathode (3081) and a dust removal electric field anode (3082). The dust removal electric field cathode (3081) and the dust removal electric field anode (3082) are used to generate an ionization dust removal electric field. By means of the present system for removing dust from air (101), particulate matter can be effectively removed from air.

A dust removal method for engine exhaust gas includes the steps of using an exhaust gas ionization dust removal electric field to gather particles in the exhaust gas, and using same to charge an exhaust gas electret element (205). The exhaust gas electret element (205) is close to or is provided at an outlet of an exhaust gas electric field device (1021). The dust removal method for engine exhaust gas can efficiently treat the engine exhaust gas and exhaust gas emissions.

A dust removal method for engine exhaust gas includes the steps of using an exhaust gas ionization dust removal electric field to gather particles in the exhaust gas, and using same to charge an exhaust gas electret element (205). The exhaust gas electret element (205) is close to or is provided at an outlet of an exhaust gas electric field device (1021). The dust removal method for engine exhaust gas can efficiently treat the engine exhaust gas and exhaust gas emissions.

An engine exhaust dust removal system includes an exhaust dust removal system inlet, an exhaust dust removal system outlet and an exhaust electric field device. The engine exhaust dust removal system has a good dust removal effect and is able to effectively remove particulate matters from the engine exhaust.

An engine exhaust dust removal system includes an exhaust dust removal system inlet, an exhaust dust removal system outlet and an exhaust electric field device. The engine exhaust dust removal system has a good dust removal effect and is able to effectively remove particulate matters from the engine exhaust.

An electrostatic precipitator including an outer electrode of a tubular shape whose internal space is passed through by gas to be processed, and an inner electrode arranged in the internal space so as to be coaxial with the outer electrode, is provided. A ratio Ra/Rb being a ratio of an outer radius Ra of the inner electrode to an inner radius Rb of the outer electrode is smaller than 1/e (where e is a base of a natural logarithm). The ratio Ra/Rb may be smaller than ½e. The outer radius Ra of the inner electrode may be from 1 mm to 10 mm, and the inner radius Rb of the outer electrode may be from 10 mm to 100 mm.

An air dust removal system (101) and method, comprising a dust removal system inlet, a dust removal system outlet, and an electric field device. The electric field device comprises an electric field device inlet (1011), an electric field device outlet (1012), a dust removal electric field cathode (10142), and a dust removal electric field anode (10141). The dust removal electric field cathode (10142) and the dust removal electric field anode (10141) are used to generate an ionizing dust removal electric field. The present air dust removal system (101) and method may effectively remove particulate matter from the air.

An air dust removal system (101) and method, comprising a dust removal system inlet, a dust removal system outlet, and an electric field device. The electric field device comprises an electric field device inlet (1011), an electric field device outlet (1012), a dust removal electric field cathode (10142), and a dust removal electric field anode (10141). The dust removal electric field cathode (10142) and the dust removal electric field anode (10141) are used to generate an ionizing dust removal electric field. The present air dust removal system (101) and method may effectively remove particulate matter from the air.

An engine tail gas ozone purifying system and method. The engine tail gas ozone purifying system comprises reaction fields (220, 202) used for mixture reaction of an ozone stream and a tail gas stream. A large amount of urea does not need to be added and the purification effect is good.