Managing Hazardous Waste with Electricity

Conventional cleanup of dilute air emissions

The concentration of a flammable vapor or gas in the circulating air must be kept below the flash point. To avoid risk, the exhaust air from some reactors, furnaces, and dryers cannot be recirculated directly. This air must be depleted of most of the molecules that can burn or explode in the presence of oxygen when their concentrations reach the flash point.

Several proposed processes can decrease emissions from such a lean fuel. These emissions are often hazardous and polluting, and sometimes they emit a foul odor. Aside from condensation and absorption, processes may involve the combustion of concentrated vapors in incinerators or the assisted combustion of dilute vapors in incinerators.

Conventional incinerators fall into two categories: catalytic and thermal. Catalytic incinerators can easily become poisoned. Thermal incinerators, on the other hand, are expensive. The exhaust from thermal incinerators has to be heated to 850°C by adding fuel, leading to more CO₂ emissions.

ECP proposes a GlidArc-I or GlidArc-II assisted combustion of flammable volatile pollutants, mostly the Volatile organic Compounds (VOC). Two technologies are available based on some of our associates know-how:

o Direct assisted incineration of diluted VOC (see some examples below), or

o Sorption/desorption process for concentrate the diluted VOC and then their GlidArc assisted combustion

Pilot plant with 36 GlidArc-I electrodes for 3000 m³/h direct air cleaning from diluted VOC

Some examples

Test pollutant	initial conc. ppm	removal-rate %	energy needed kWh per kg C
xylene	200	100	80
heptane	2200	100	60
toluene	1800	92	60
CH₃COC₂H₅	2000	66	100
C₂Cl₄	500	100	900

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