plans address facility maintenance, leak inspections, and calibration schedules for monitoring equipment. The training plans are intended to address hazardous-material safety and facility operations.
The American Society of Mechanical Engineers has developed a certification guideline for hazardous waste-incinerator operators.
For the most recently completed waste incinerators, particularly hazardous-waste incinerators, environmental regulations have led to extensive monitoring of key incineration process conditions, including waste feed rates; feed rates of ash, chlorine, and toxic metals (determined by sampling and analysis of the waste stream); combustion temperatures; gas velocity (or gas residence time); facility-specific air-pollution control-system operating measures; and stack-gas concentrations of O2, CO, total hydrocarbons, HCl, NOx, and SOx, and opacity (see Chapter 6). Computerized systems collect and record process data, automatically control such process conditions as combustion temperature (by varying fuel feed and air flow rates), and automatically cut off waste feeds if operating conditions stray outside limits set by permits. For example, a low combustion temperature or high stack-gas CO concentration might initiate an automatic waste-feed cutoff.
RCRA regulations for hazardous-waste incinerators require continuous monitoring of important air-pollution control-system operating conditions, including pressure drops across venturi scrubbers, pH of acid-gas absorber scrubbing solutions, voltage or power supplied to electrostatic collectors, and fabric-filter pressure drops or triboelectric sensor readings.1 Stack-gas monitors are often used to monitor the performance of the air-pollution control system directly for such measures as HCl, SO2, NOx, and opacity.
With electronic transmission of such sensor outputs, the performance of the control and monitoring systems could be more-readily displayed and monitored. Reliable continuous emission monitors (CEMs) for dioxins and furans or for metals would be desirable, because automatic devices electronically linked to such devices (for example, to optimize the injection of alkaline and carbon reagents and water in the emissions control devices) could directly control those emissions of greatest potential health consequence. Such arrangements have been in use for continuous automatic control of acid gases for some time. CEMs for mercury have undergone in-use testing in Europe, for example see Felsvang and Helvind (1991).
Triboelectricity refers to an electric charge that is generated by friction.