Final Report: Advanced Monitoring System for Effective NOx Control

EPA Contract Number: 68D00211
Title: Advanced Monitoring System for Effective NOx Control
Investigators: Johnson, Stephen
Small Business: ADA Environmental Solutions L.L.C.
EPA Contact:
Phase: I
Project Period: September 1, 2000 through March 1, 2001
Project Amount: $70,000
RFA: Small Business Innovation Research (SBIR) - Phase I (2000) RFA Text |  Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , SBIR - Monitoring , Small Business Innovation Research (SBIR)


Selective Catalytic Reduction systems rely on an accurate measure of the NOx molar flux to control the amount and distribution of ammonia reagent entering the reactor. The NOx flux is usually derived from a single-point NOx concentration measurement or look-up table value, and a calculated flue gas flow rate. The reagent flow is then trimmed based on a feedback signal from the NOx CEM to maintain the desired NOx emission. This control scheme results in unnecessarily high operating costs when inlet NOx deviates from expected values. ADA-ES has shown the feasibility of adapting SCR sootblowers into movable sampling probes during the time that they are not needed for cleaning the catalyst. The purpose of the research was to demonstrate the concept and to refine the design of the Sootsniffer.

Summary/Accomplishments (Outputs/Outcomes):

A Sootsniffer design was established and updated based on visiting end-user sites and receiving feedback on design and ease of use. Bills of material were prepared for two design options. A description is provided of the use of the Sootsniffer as part of an integrated NOx control package.


The Sootsniffer is a cost-effective technology for power plants that have already or will be installing selective catalytic reduction NOx control systems. The advantages of the Sootsniffer technology (patent-pending) are quantified in terms of improved reagent usage, less downtime for air heater washes, improved flyash sales, and online tracking of catalyst reactivity.

Supplemental Keywords:

Selective Catalytic Reduction, NOx Control, Power Generation., RFA, Scientific Discipline, Air, Ecosystem Protection/Environmental Exposure & Risk, Chemical Engineering, air toxics, Environmental Chemistry, Chemistry, Monitoring/Modeling, Environmental Monitoring, tropospheric ozone, Engineering, Environmental Engineering, ambient air quality, Nitrogen Oxides, Nox, emission control strategies, monitoring, NOx molar flux, stratospheric ozone, air pollutants, NOx control, ambient air, ambient monitoring, air sampling, air quality data, emissions control, atmospheric monitoring