US 2013/0259741 A1 · MULTI-STAGE NON-THERMAL PLASMA APPARATUS AND METHOD FOR TREATING FLUID FLOWS

Abstract

A non-thermal plasma (NTP) system treats fluid flows (e.g., air) containing pollutants (e.g., VOCs; particulate) using two or more stages, each operated to produce NTP with a respective frequency targeted toward one or more pollutants. NTP generation cell assemblies or dielectric barrier discharge devices are arranged in stages along a flow path. Parallel flow paths with multiple stages may be employed. NTP fields in successive stages operate at a different frequency, power density and/or waveforms, which are controlled to be a vibrational harmonic of a targeted compound. Power density can be adjusted to only create gaseous ionized species or to incinerate organic airborne, suspended particulate in situ. Automatic fault detection employs a split ground current so that an imbalance indicates a fault. A faulted component is automatically isolated. Automatic re-routing allows operation with only slightly degraded performance.

Claims31

Dependent claims

An apparatus to treat fluid streams, comprising:

a first stage non-thermal plasma (NTP) generation cell assembly, the first stage NTP generation cell assembly operable to produce a first NTP field in a first flow path;
a second stage NTP generation cell assembly, the second stage NTP generation cell assembly operable to produce a second NTP field in the first flow path positioned relatively downstream from the first NTP field in the first flow path;
and
a control system coupled to control the first and at least the second NTP generation cell assemblies to respectively produce during a first period:
the first NTP field with a first set of NTP field characteristics and the second NTP field with a second set of NTP field characteristics, the second set of NTP field characteristics different than the first set of NTP field characteristics.

2 more elements

A method of operating an apparatus to treat fluid streams, comprising:

operating a first stage non-thermal plasma (NTP) generation cell assembly during a first period to produce a first NTP field in a first flow path with a first set of NTP field characteristics;
and
operating a second stage NTP generation cell assembly during the first period to produce a second NTP field in the first flow path positioned relatively downstream from the first NTP field in the first flow path with a second set of NTP field characteristics, the second set of NTP field characteristics different than the first set of NTP field characteristics.

A method of operating an apparatus to treat fluid streams, comprising:

operating a first stage non-thermal plasma (NTP) generation cell assembly during a first period to produce a first NTP field in a first flow path with a first set of NTP field characteristics;
detecting a characteristic that is indicative of a first stage ratio of at least one characteristic of the first set of NTP field characteristics and at least one operational characteristic of the first stage NTP generation cell assembly, where the first stage ratio is indicative of an interaction of the first NTP field and a number of compounds in a fluid stream that passes through the first NTP field;
identifying at least one frequency of the first NTP field at which the first stage ratio is optimized;
and
controlling the operation of the first stage NTP generation cell assembly to oscillate around the identified frequency during at least one subsequent period based at least in part on a feedback indicative of the first stage ratio.

2 more elements

Dependencies are inferred from the claim text.

Multi-stage non-thermal plasma apparatus and method for treating fluid flows

Life of this patent

Multi-stage non-thermal plasma apparatus and method for treating fluid flows

Life of this patent

Abstract

Claims31