An electrostatic dust collection apparatus and an air purifier including such the electrostatic dust collection apparatus are provided. The electrostatic dust collection apparatus of the invention includes a sheet collection electrode, an insulative bearing member and a plurality of discharge electrodes. A first surface of the sheet collection electrode faces and is parallel to a second surface of the insulative bearing member. A plurality of grooves are formed on and across the second surface of the insulative bearing member, and are parallel to one another. Each discharge electrode corresponds to one of the grooves, and is disposed in the corresponding groove. An air passage is defined between the sheet collection electrode and the insulative bearing member, and allows an air to be treated to pass through. The discharge electrodes charge a plurality of floating particles in the air to be treated. The sheet collection electrode collects the charged particles.

An electrostatic separator or precipitator through which an air stream to be cleaned of particles flows in a longitudinal direction includes at least one electrospray ionization source, which is supplied with a positive potential and can be implemented, for example, by the tips of a graphite fiber bundle, and a collector unit arranged downstream for particle separation and having parallel collector and driver plates. The ion flow from the corona zone is additionally homogenized and spread by an upstream collector element, in particular a collector grid, upstream of the at least one electrospray ionization source, so that high particle separation rates can be achieved with minimal ozone emissions. Alternatively, or in addition, the ion flow from the corona zone can be homogenized downstream of the at least one spray ionization source by one or more border counter-electrodes.

An electrostatic separator or precipitator through which an air stream to be cleaned of particles flows in a longitudinal direction includes at least one electrospray ionization source, which is supplied with a positive potential and can be implemented, for example, by the tips of a graphite fiber bundle, and a collector unit arranged downstream for particle separation and having parallel collector and driver plates. The ion flow from the corona zone is additionally homogenized and spread by an upstream collector element, in particular a collector grid, upstream of the at least one electrospray ionization source, so that high particle separation rates can be achieved with minimal ozone emissions. Alternatively, or in addition, the ion flow from the corona zone can be homogenized downstream of the at least one spray ionization source by one or more border counter-electrodes.

A dust collector includes a casing, a fan, a filtering element, an electric field generator and an electrostatic precipitator. The casing includes an inlet, an outlet and a channel. The channel is arranged between the inlet and the outlet. An ambient airflow is introduced into the channel through the inlet by the fan. Moreover, portions of suspended particles in the airflow are filtered off by the filtering element. The electric field generator generates an electric field. The suspended particles passing through the electric field generator have a first electrical polarity. The electrostatic precipitator has a second electrical polarity, wherein the first electrical polarity and the second electrical polarity are opposite. The suspended particles with the first electrical polarity are adsorbed by the electrostatic precipitator.

A dust collector includes a casing, a fan, a filtering element, an electric field generator and an electrostatic precipitator. The casing includes an inlet, an outlet and a channel. The channel is arranged between the inlet and the outlet. An ambient airflow is introduced into the channel through the inlet by the fan. Moreover, portions of suspended particles in the airflow are filtered off by the filtering element. The electric field generator generates an electric field. The suspended particles passing through the electric field generator have a first electrical polarity. The electrostatic precipitator has a second electrical polarity, wherein the first electrical polarity and the second electrical polarity are opposite. The suspended particles with the first electrical polarity are adsorbed by the electrostatic precipitator.

Precipitator unit of a two-stage electro filter where air to be cleaned from electrically charged particles is intended to flow through the unit. Said unit comprising at least two cylindrical precipitators (10, 11) that each comprise at least two electrode elements arranged at a gap distance from each other. Each one of the precipitators (10, 11) is also intended to be connected to a high voltage source. The respective electrode elements of a precipitator (10, 11) are connected to different poles of the high voltage source. The main planes of the precipitators (10, 11) are axially spaced in the air flow direction and a cone shaped duct (21) extends between the circumference of the first precipitator (10) and a center opening (13) of the second precipitator (11). A first amount of polluted air flows across the area of the first precipitator (10) and continues afterwards through the inside of the cone shaped duct (21) and out of the unit through the center opening (13) of the second precipitator (11). A second amount of polluted air flows outside the circumference of both the first precipitator (10) and the cone shaped duct (21) in order to be cleaned by the second precipitator (11).

An electronic air filter having a plurality of electrodes supported by rigid fixtures that are attached to a common case. The rigid fixtures that support the electrodes with different electrical potentials are attached to each other or to a common body in a way that increases or maximizes the creeping discharge path along the surface. Even conductive contaminants do not, therefore, provide an electrical shortage between the electrodes.

An electronic air filter having a plurality of electrodes supported by rigid fixtures that are attached to a common case. The rigid fixtures that support the electrodes with different electrical potentials are attached to each other or to a common body in a way that increases or maximizes the creeping discharge path along the surface. Even conductive contaminants do not, therefore, provide an electrical shortage between the electrodes.

An electrostatic air cleaner may include a corona charging stage, a precipitation stage, and an air mover (fan). The corona charging stage may include a first and second array placed under electrical potential difference capable of generating a corona discharge. The first array may be substantially parallel corona wires and may be located downstream of an air penetrable second array. The precipitation stage may be downstream from the corona charging stage. The spacing between the first array and the second array may be less than the distance of the precipitation stage to the second array. The air mover may be upstream of the corona charging stage or downstream of the precipitation stage or between these stages. The arrangement allows for higher ion output downstream of the first array with the same voltage and power consumption resulting in greater particle charging and better air cleaning efficiency.

An electrostatic air cleaner may be operated according to a manner designed to achieve acceptable air quality while balancing power usage and corona electrode degradation levels. The voltage applied to the corona electrode(s) may be controlled as well as the voltage applied to repelling electrodes and air flow velocity. The air cleaner may also be operated to achieve desired particle separation.