An improved non-thermal plasma treatment method and apparatus for the pretreatment of nitric oxide-bearing exhaust gas with ethanol, either by vapor absorption or direct vapor injection, is described. Advantageously, the high vapor pressure of ethanol permits a significant portion of the ethanol to be absorbed. Moreover, the solubility of ethanol permits the ethanol to be readily scrubbed from the exhaust gas, along with the nitrogen dioxides converted from the nitric oxides. The non-thermal plasma apparatus comprises a non-thermal plasma reactor having a chamber which provides a plurality of electrodes. The apparatus further comprises an inlet and an outlet connected to the reaction chamber, permitting the exhaust gas to enter and leave the chamber. In one embodiment, the inlet is further connected to a diverter equipped with an injector, which diverts a portion of the gas stream through the ethanol bath before reinjecting the ethanol-bearing gas stream into the inlet.
RELATED APPLICATION
This is a continuation of application Ser. No. 09/086,303 filed May 28, 1998, now U.S. Pat. No. 6,139,694 METHOD AND APPARATUS UTILIZING ETHANOL IN NON-THERMAL PLASMA TREATMENT OF EFFLUENT GAS.
A non-thermal plasma reactor element is provided comprising a multi-cell stack prepared from a plurality of formed building blocks of dielectric material, the walls of the building blocks defining a cell having an exhaust passage for flowing gas to be treated therethrough. A conductive print forming an electrode and connector is disposed on at least one wall of each of the cells and outer insulative plates, disposed on opposite ends of the multi-cell stack, are provided to protect the conductive print. The non-thermal plasma reactor element includes cells defined by a single structural dielectric barrier comprising a "conductor-single structural dielectric barrier-exhaust passage-conductor" arrangement, wherein individual cells of the reactor element are defined by a single structural dielectric barrier.
A method for reducing or substantially eliminating oxides of nitrogen from an effluent gas stream, that includes providing a source of ultraviolet radiation with a precise wavelength, adding ammonia or an ammonia based reagent to the effluent stream, upstream of the ultraviolet radiation source, controllably operating the ultraviolet radiation source to irradiate the effluent stream flowing in the duct and substantially reducing or eliminating oxides of nitrogen by promotion a reaction of ammonia with the oxides of nitrogen to produce N.sub.2 and H.sub.2O, and also thereby destroying any surplus ammonia. This process can also be modified to oxidize carbon monoxide and VOC's to CO.sub.2 and H.sub.2O.
