Assessing Particulate Control Technologies for Near-Zero Emissions Plants
A recent EPRI report evaluates the capabilities of current and developing particulate control technologies to meet extremely low, continuous particulate emission limits. Interest in this topic is due to concerns about the environmental impact of coal-fired power plants and the trend towards lower and lower particulate emission limits proposed by regulators and environmental groups.
The report, entitled Particulate Control for Near-Zero Emissions Plants (1016472), characterizes the capabilities of existing electrostatic precipitators (ESPs) and fabric filters (FFs) and identifies several new promising particulate control technologies capable of limiting emissions to very low values. The report also includes an extensive discussion of the difficulties of accurately measuring particulate concentrations that are encountered in “near-zero emissions” (NZE) situations.
Qualified funders may view or download a copy of the report by clicking on the link below.
How to Apply the Results
The information in this report provides background material needed to anticipate future
particulate control technology needs for the power-producing industry. These findings should be useful to anyone planning a new coal-fired plant or concerned about significantly reducing emissions from existing plants.
Background
There is increasing pressure from regulatory agencies for coal-fired power plants to comply with air emissions standards that are much more stringent than the current U.S. Environmental Protection Agency (EPA) New Source Performance Standards (NSPS) and that approach NZE of particulate matter (PM). EPRI, DOE and the Coal Utilization Research Council have established theoretical Near-Zero PM emission targets of 0.005 lb/106 Btu (≈ 5 mg/Nm3) to be achieved by the year 2010, and 0.002 lb/106 Btu (≈ 2 mg/Nm3)1 by 2020. These targets facilitate theoretical investigations such as this work so as to evaluate the potential for existing and emerging PM technology at meeting these target values.
Findings
· There is a general consensus that both ESPs and FFs are capable of limiting particulate emissions to the 0.005- to 0.002-lb/mmBtu range that is currently considered to be the target for the particulate emission limit for near-zero-emission power plants. In fact, some major pollution control equipment suppliers state that they are ready to guarantee outlet emissions at the higher end of this range.
· However, guarantees at the lower end of the range are unlikely. This reluctance is due to both the lack of experience with operation in this challenging range and to the difficulties of trying to accurately measure particulate concentrations at these extremely low levels.
· The wet ESP is identified as a promising new particulate “polishing” technology for the industry that is potentially capable of producing extremely low particulate emission levels on a continuous basis.
· A number of other emerging technologies hold the promise of providing low emissions. These technologies include the Dielectric-Coated Discharge Electrode, Sieving ESP, and the ElectroCore Separator. However, all of these are in an early stage of development and, hence, it is not possible to assess their capabilities to meet extremely low limits with confidence.
For more information contact Ralph Altman, 423-899-0072, .
View or download Particulate Control for Near-Zero Emissions Plants (1016472).
2