Using CEMS for Emissions Abatement in Cogeneration Facilities
Cogeneration facilities are considered to be among the most modern, energy-efficient producing facilities because of their superior environmental performance. Their purpose is to generate and distribute steam which can be used for heating, domestic hot water heating, humidification, sterilization of water and distilling water. During the cogeneration process, steam passes through a double automatic controlled extraction pressure and condensing steam turbine generator, and as a result, the electricity it produces becomes a beneficial byproduct. The combination of these results in a thermal efficiency greater than that of any plant built strictly for power generation.
Cogeneration greatly reduces the environmental impact; in addition, these facilities rely heavily on advanced technologies and continuous emissions monitoring systems (CEMS) to ensure strict regulatory compliance with State and Federal environmental agencies such as the EPA.
Cogeneration facilities can utilize multiple and varied fuel sources. These fuels can include natural gas, oil, coal, wood, various forms of bio-solids, and even tires. Combined cycle cogeneration facilities are becoming popular in meeting increasing energy demands. A typical facility will include a gas turbine, heat recovery steam generator (HRSG) and a steam turbine. The size of cogeneration facilities can vary greatly from small hospitals to large petrochemical complexes.
Since cogeneration facilities vary so significantly in size, fuel burned, pollution abatement equipment installed, and geographic location, the continuous emissions monitoring (CEM) requirements placed upon a given facility will also vary from plant to plant. The primary federal regulations defining CEM requirements are found in 40 CFR 60 and 40 CFR 75. The latter is also known as the Clean Air Act Amendments of 1990. However, state and local agencies do have the ability to impose additional and/or stricter requirements for the monitoring and control of pollutants. The federal regulations, based upon the fuel(s) utilized and the generating capacity of the facility, may require the monitoring of sulfur dioxide (SO2), oxides of nitrogen (NOx), opacity, a diluents [carbon dioxide (CO2) or oxygen (O2) and stack flow. In addition to the above requirements, state and local agencies may also call for the monitoring of carbon monoxide (CO) and, in those plants where SCR or SNCR is utilized for NOx reduction, may require monitoring of ammonia (NH3) as well.
Flameproof gas analyzers provide single and multicomponent gas analysis. Coupled with a remote-mounted sample conditioning system and flow distribution/system controller, these CEMS become truly modular emissions monitoring systems. This configuration allows sample extraction and conditioning anywhere along the sampling train, reducing costs for heated sample lines, equipment racks and instrument shelters. To check out a wide range of other possible configurations click HERE.
The growing significance of cogeneration combined with the unique requirements of each plant make CEMS an ideal solution since they can be designed specifically for each cogeneration plant while providing a field-proven analysis technology that is both highly accurate and cost-effective.