Claims
- 1. A method of reducing pollutants in an exhaust gas, comprising:
- subjecting said exhaust gas to a first pulsed corona discharge at a discharge voltage and a pulse repetition rate in respective ranges suitable for oxidizing HC and CO pollutants in said exhaust gas,
- subjecting said exhaust gas to a second pulsed corona discharge at a discharge voltage and a pulse repetition rate in respective ranges suitable for reducing NO.sub.x in said exhaust gas, and
- dynamically and independently adjusting the respective pulse repetition rates of said first and second corona discharges to maintain the levels of HC, CO and NO.sub.x in said exhaust gas withing respective allowable limits.
- 2. The method of claim 1, wherein said HC, CO and NO.sub.x levels are determined by
- directly measuring the amounts of HC, CO and NO.sub.x in said exhaust gas.
- 3. The method of claim 2, wherein said HC, CO and NO.sub.x are sensed in said exhaust gas subsequent to said first and second corona discharges.
- 4. The method of claim 1, wherein said HC, CO and NO.sub.x are generated by an engine, and said HC, CO and NO.sub.x levels are determined in response to sensing operating characteristics of said engine.
- 5. The method of claim 4, wherein said engine's sensed operating characteristics comprise rate of rotation, temperature, intake pressure and/or oxygen concentration.
- 6. The method of claim 1, wherein said HC, CO and NO.sub.x are generated by an engine, and said HC, CO and NO.sub.x levels are determined in response to sensing drive control characteristics of said engine.
- 7. The method of claim 6, wherein said drive control characteristics comprise throttle position, throttle position history, braking, acceleration, slope of road incline and/or slope of road decline.
- 8. The method of claim 1, wherein said maximum allowable levels are provided by an intelligent vehicle highway system (IVHS).
- 9. The method of claim 2, wherein said levels of HC and CO are sensed in said exhaust gas subsequent to said first corona discharge, and said level of NO.sub.x is separately sensed in said exhaust gas subsequent to said second corona discharge.
Parent Case Info
This is a division of application Ser. No. 08/689,999 filed Aug. 19, 1996.
US Referenced Citations (9)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0585047 |
Mar 1994 |
EPX |
0744802A2 |
Nov 1996 |
EPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
689999 |
Aug 1996 |
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