Covanta Energy

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Covanta Holding Corporation
Public
Traded as NYSECVA
Industry Renewable Energy/Waste Management
Number of employees
3,300
Website www.covanta.com

Covanta Energy Corporation (formerly the Ogden Corporation) owns and operates worldwide over forty new generation waste combustion facilities with added benefit of energy recovery, also known as waste-to-energy or energy-from-waste power generation plants. Facilities operated by Covanta produce electricity for approximately one million homes in communities across North America by converting municipal solid waste into renewable energy. The company’s operations offset the production of approximately 20 million tons of carbon dioxide annually by producing electricity without utilizing fossil-fuel and by diverting waste from landfills.[citation needed] The energy-from-waste process also includes the extraction of ferrous (steel) and non-ferrous (aluminum etc.) metals either before or after the combustion process. Approximately 400,000 tons of ferrous steel and non-ferrous metals are extracted at the company's facilities annually for recycling, avoiding mining activities associated with the production of a similar amount of virgin metals.

Mass Burn Process[edit]

Mass burn technology, the most common municipal solid waste-to-electricity technology, involves the combustion of unprocessed or minimally processed refuse. The major components of a mass burn facility include:

  • Refuse receiving, handling, and storage systems
  • The combustion and steam generation system (a boiler)
  • A flue gas cleaning system
  • The power generation equipment (steam turbine and generator)
  • A condenser cooling water system
  • A residue hauling and storage system
  • Incoming trucks deposit the refuse into pits, where cranes then mix the refuse and remove any bulky or large non-combustible items (such as large appliances). The refuse storage area is maintained under pressure less than atmospheric in order to prevent odors from escaping. The cranes move the refuse to the combustor charging hopper to feed the boiler.

Heat from the combustion process is used to turn water into steam, with the steam then routed to a steam turbine-generator for power generation. The steam is then con-densed via traditional methods (such as wet cooling towers or once-through cooling) and routed back to the boiler. Residues produced include bottom ash (which falls to the bottom of the combustion chamber), fly ash (which exits the combustion chamber with the flue gas [hot combustion products]), and residue (including fly ash) from the flue gas cleaning system.

The combined ash and air pollution control residue typically ranges from 20 percent to 25 percent by weight of the incoming refuse processed. This ash residue may or may not be considered a hazardous material, depending on the makeup of the municipal waste.

It may be possible to avoid the production of hazardous ash by preventing the sources which create hazardous waste from enter-ing the system. It is also possible to treat the ash. Both of these methods avoid the costs of disposal at a limited number of landfills classified as able to handle hazardous materials. Non-hazardous ash can be mixed with soils for use as land-fill cover, or can be sold (or given away) for such beneficial uses as pavement aggregate.[1]

Permitting Issues for Mass Burn Facilities[edit]

Some of the major issues associated with mass burn facilities include:[2]

  • Ability to meet air quality requirements
  • Possible classification of the ash as a hazardous material
  • Disposal of ash and other by-products
  • Possible conflict with adjacent land uses
  • Disturbances to biological resources
  • Use of large amounts of water for cooling purposes (if wet cooling towers are used)
  • Changes to visual quality due to power plant structures and traffic patterns
  • Transportation impacts from numerous truck trips from the refuse source to the mass burn facility (note that collection and transportation would already be occurring, so the mass burn facility would only cause a change in traffic patterns)
  • Likely public opposition because of uncertainties over health, safety, odor, and traffic impacts (since it is most economical for the facility to be located near urban centers where the waste is generated)
  • Possible conflicts between using MSW for electricity generation and programs/goals for waste reduction techniques and recycling
  • Possible hazardous materials leakage that may necessitate site cleanup after facility closure

Other[edit]

A few of the company's facilities have been cited for air emissions violations and have experienced some labor relations disputes all of which have been settled appropriately. According to a press release issued on July 15, 2011 by The Connecticut Office of the Attorney General and the Department of Energy and Environmental Protection (DEEP), the company paid $400,000 in fines for a 2010 air emission violation at its Wallingford, CT facility. The press release also stated that the DEEP consulted with the Connecticut Department of Public Health and verified that despite the violation, the amount of emissions in the air in the vicinity of the facility was still within applicable health-based standards and did not pose a threat to public health.[3]

It is a subsidiary of Covanta Holding Corporation, which is located in Morristown, New Jersey. The company's chairman is Sam Zell. In 2004, Danielson Holding Corporation acquired Covanta for $30 million following the latter's filing of a Chapter 11 bankruptcy in April 2003.[4] Danielson owned the National American Insurance Company of California.[citation needed]

References[edit]

  1. ^ "Municipal Solid Waste Power Plants". California Energy Commission. 
  2. ^ "Municipal Solid Waste Power Plants". California Energy Commission. 
  3. ^ "Settlement Reached with Covanta for Air Emissions Violations at Plant in Wallingford". Retrieved 9 February 2012. 
  4. ^ "Covanta Energy Corporation". Covanta Energy Corporation. FundingUniverse. Retrieved 17 July 2011. 

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