Research Projects

Project at a Glance

Project Status: complete

Report Published February 1982:

Title: Assessment of simultaneous use of NOx control systems on stationary sources in California

Principal Investigator / Author(s): Witz, J R

Contractor: The Aerospace Corporation

Contract Number: A9-117-30

Research Program Area: Emissions Monitoring & Control

Topic Areas: Stationary Sources


The costs and performance potential were assessed for the simultaneous use of NOx control systems applied in various combinations and at various control levels on 11 stationary sources. NOx control sytems which were studied included combinations of low NOx burners (LNB), selective non-catalytic reduction (SNCR), and selective catalytic reduction (SCR). The stationary sources, totalling 11 different installations, include refinery process heaters and industrial boilers of various sizes and types, a carbon monoxide boiler, and a glass melting furnace.

Primary emphasis was on NOx reduction costs and corresponding applicability of various control strategies as applied to major emission sources for a range of sizes and equipment operating conditions. In addition, the cumulative performance potential of each combination control option was assesed.

It was concluded that generally the applicability of a combination of NOX controls is feasible, but the cost-effectiveness is uniques for each unit examined. In addition, overall system complexity increases as denitrification systems are added. However, some general trends were detected:

1. Application of NOx controls to refinery heaters is, on the average, less costly than for industrial boilers;
2. Application to larger units is, on the average, less costly than for smaller units;
3. The combination of LNB + SCR is generally competitive with SCR at control levels between 80% to 90% NOx reduction;
4. From 70% to 90% reduction , SCR is usually more cost-effective;
5. at 70% NOx removal LNB + SNCR is more attractive; and
6. at 50% and 40% NOx reduction, SNCR and LNB, respectively, have the lowest cost.

Capital investment cost estimates are provided in mid-1981 dollars and reflect estimated retrofit complexity factors for the various installations. Annual control costs in terms of dollars per pound NOx removed and dollars per million Btu thermal input are also reported.


For questions regarding this research project, including available data and progress status, contact: Heather Choi at (916) 322-3893

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