Loading...

Monday, April 28, 2008

Emission Controls

Volatile organic compounds (VOC) and particulate matter (PM) can be controlled using two technologies: 1) Wet Electrostatic Precipitator (WESP) and 2) Regenerative Thermal Oxidizer. The WESP reduces the concentration of particulate matter in the gas stream to levls that are both acceptable for discharge to the atmosphere and suiable for treatment in downstream VOC control equipment. The RTO destroys VOCs with high-temperature combustion(1,500 degrees F).

With respect to air emission control, gases must be cleaned in order to meet local, state and federal environmental requirements. Treatment of these gases with the combined WESP/RTO system, right, results in a gas stream that exceeds all modern standards for the emission of particulate matter VOCs with a minimum of energy and maximum operational reliability

Operation of the wet device starts by spray quenching the gas stream to the wet-bulb temperature with recycled water. The quenching process serves two functions: first, the sprays serve to remove a large portion of the coarse particles that come from the dryer, and second, the resulting temperature reduction causes heavy organic vapors to condense into particles. After quenching, the gas stream passes upward into an array of discharge and collecting electrodes. Here, the electrostatic action takes over to charge, precipitate and remove over 90 percent of the remaining particles. Exiting the top, the clean gas is now suitable for treatment in the RTO.

The RTO system reduces the VOCs (including HAPs) by high-temperature combustion. Given the large volumes of gas to be treated, simply burning the gas stream at the required 1500˚F (as in a simple, direct-fired oxidizer) [is] economically unfeasible. Therefore, alternative energy-saving techniques [should be] employed. RTOs work by alternating the incoming gas stream through heat recovery beds prior to exposure to a 1500˚F combustion zone. These heat-recovery beds are filled with ceramic material that absorbs heat from the combustion chamber. Keeping the heat in these beds greatly minimizes the total energy expended. Typically, the temperatures rise from inlet to outlet of an RTO system is in the range of 75˚F, a far cry from the 1500˚F rise that would by required by a simple direct-fired oxidizer. Yet, the gas stream is exposed to the 1500˚F required for excellent VOC and HAP destruction.

(Source: Pollution Engineering magazine: "The Search for Economical Emission Controls")

Lieberman-Warner America's Climate Security Act of 2007

America's Climate Security Act (S. 2191), cosponsored by Senators Joe Lieberberman and John Warner, calls for a cap on greenhouse gas (GHG) emissions from most of the U.S. economy beginning in 2012, with a reduction of approximately 63 percent by 2050. Lieberman-Warner establishes a cap-and-trade system and proposes an initial auction of 26 percent of allowances in 2012, moving to an auction of almost 70 percent of the allowances by 2031. An offset provision in Lieberman-Warner allows an entity to meet up to 15 percent of its compliance obligations with specified domestic offsets.

Highlights of the Lieberman-Warner Bill:

[1] Emission allowances will begin in 2012 with a declining cap on GHGs to 2030. A GHG registry and a GHG emission allowance transfer system will be established for "covered facilities." Facilities in the electric power and industrial sectors are "covered" as are facilities that produce or import petroleum or coal-based transportation fuel or chemicals.

[2] Emission allowances will initially be given to load-serving entities that deliver electricity to retail consumers. An "Emission Allowance Account" will also be provided for covered facilities in the electric power and industrial sectors.

[3] A "Climate Change Credit Corporation" will auction emission allowances. Auction proceeds will be used for several programs including one for zero- or low-carbon energy technologies and one for advanced coal and sequestration technologies.

[4] Allowances can be traded. A board will oversee the national GHG emission market and can provide cost relief measures if it determines that "the market poses significant harm to the U.S. economy." A domestic offset program will be set up to sequester GHGs in agriculture and forests.

[5] The act also supports carbon capture and sequestration by amending the Safe Drinking Water Act to permit commercial-scale underground injection of CO2 and establishing a task force to study the cost implications of potential federal assumption of liability for closed geological storage sites. The Secretary of Energy will be required to study the feasibility of constructing geological CO2 sequestration facilities and pipelines for the transportation of CO2 for sequestration or enhanced oil recovery.

[6] The SEC will be required to direct securities issuers to inform investors of material risks related to climate change. An interagency group will be set up to determine whether foreign countries have addressed GHGs.

State Regional Greenhouse Gas Initiatives

(Electric Light & Power, Mar, Apr, 2008)


Friday, April 18, 2008

EPA Publishes Annual National Greenhouse Gas Inventory

The U.S. Environmental Protection Agency has released the national greenhouse gas inventory, which finds that overall emissions during 2006 decreased by 1.1 percent from the previous year. The report, Inventory of U.S. Greenhouse Gas Emissionsand Sinks: 1990-2006, is the latest in an annual set of reports that the U.S submits to the Secretariat of the United Nations Framework Convention on Climate Change, which sets an overall framework for intergovernmental efforts to tackle the challenge posed by climatechange. Each year since 1993, EPA’s experts have built a comprehensive inventory of U.S. greenhouse gas emissions. Our understanding of emission sources is paramount to combating climate change.

Total emissions of the six main greenhouse gases in 2006 were equivalent to 7,054.2 million metric tons of carbon dioxide. These gases include:
1) carbon dioxide,
2) methane,
3) nitrous oxide,
4) hydrofluorocarbons,
5) perfluorocarbons and
6) sulfur hexafluoride.
The report indicates thatoverall emissions have grown by 14.7 percent from 1990 to 2006, while the U.S. economy has grown by 59 percent over the same period.The decrease in emissions in 2006 was due primarily to a decrease in carbon dioxide emissions associated with fuel and electricity consumption. The following factors were primary contributors to this decrease:

compared to 2005, 2006 had warmer winter conditions, which decreased consumption of heating fuels, as well as cooler summer conditions, which reduced demand for electricity;

restraint on fuel consumption caused by rising fuel prices, primarily in the transportation sector; and

increased use of natural gas and renewables in the electric power sector.
EPA prepares the annual report in collaboration with experts from multiple federal agencies and after gathering comments from a broadrange of stakeholders across the country.The inventory tracks annual greenhouse gas emissions at the nationallevel and presents historical emissions from 1990 to 2006. The inventory also calculates carbon dioxide emissions that are removed from theatmosphere by “sinks,” e.g., through the uptake of carbon by forests,vegetation and soils.Information on the greenhouse gas inventory report

Friday, April 04, 2008

Nikola Tesla and Thomas Edison Made Electricity Useful



Nikola Tesla, left, and Thomas Edison, right, revolutionized American society by developing the first electricity distribution systems. Edison developed and promoted direct current (DC) and Tesla developed and promoted alternating current (AC) and they became rivals in commercializing their respective electrical systems. Tesla won. Unlike DC, AC could be stepped up to very high voltages with transformers, sent over thinner and less expensive wires, and stepped down again at the destination for distribution to users. Thomas Edison failed because he could not practically and economically send DC very far. Nikola Tesla developed and patented much of AC power generation and distribution technology used today.

Edison's company established the first investor-owned electric utility in 1882 and his generating station's electrical power distribution system provided 110 volts DC to 59 customers in lower Manhattan. George Westinghouse and Edison became adversaries because of Edison's promotion of direct current for electric power distribution instead of the more easily transmitted AC system invented by Tesla and promoted by Westinghouse. George Westinghouse purchased Teslas patents and profited from them. Even with these patents, the company Edison founded, General Electric, is many times the size of Westinghouse. Telsa fell into relative obscurity, he is rarely mentioned in the history books. Nikola Tesla does not get the kind of recognition he truly deserves, even though he is the creator of polyphase transformers and machinery. Nikola Tesla is the real reason why we use 3-phase distribution.

Edison did not invent the first electric light bulb, but instead invented the first commercially practical incandescent light. Edison patented an electric distrubution system in 1880, which was essential to capitalize on the invention of the electric lamp. Nearly all of Edison's patents were utility patents but the phonograph patent was unprecedented as the first device to record and reproduce sounds. The key to Edison's fortunes was the telegraph. This allowed him to make his early fortune with the stock ticker, the first electricity-based broadcast system. Edison was also granted a patent for the motion picture camera. (Wikipedia: Tesla, Edison) (Madhu Siddalingaiah)

Tuesday, April 01, 2008

Maryland & Virginia Utilities Get Green Lights

The Virginia State Corporation approved on March 31, 2008 Dominion Virginia Power's plan to build a $1.8 billion 585-megawatt coal-burning power plant in Wise County, Virginia. Dominion has 2.3 million customers in the state. The commission designated the plant as a "conventional coal facility" instead of one that is "carbon capture compatible." The plant must still be approved by the Virginia Air Pollution Control Board. The plant was named "The Virginia City Hybrid Energy Center and the target date for operation is 2012. (The Washington Post)

The Maryland Public Service Commission has found 'no evidence' that Baltimore Gas and Electric and its parent company, Constellation Energy, colluded to charge higher prices in purchasing electricity for 1.1 million customers it served in 2005-06. Since electricity deregulation in 1996 electricity prices have been set in auctions held by utilities, which buy power from unregulated suppliers. The 2005-06 auction was the first since the rate caps that followed deregulation were removed. It resulted in a 72 percent increase in electric bills for BGE customers. Of course the deregulation was flawed because it kept caps on retail rates while releasing caps on wholesale rates. The investigation was to find out whether the auction was rigged because BGE paid much more for power than the cost to produce it and bought most of its electricity from its corporate parent. Hmmmm. (The Washington Post)