WASHINGTON, DC - The Office of Fossil Energy's National Energy Technology Laboratory continued its efforts to address the cleaner, more cost-effective use of fossil fuels with the award of four patents in 2006.
"This effort illustrates the caliber of engineers and scientists working toward meeting the goals of our National Energy Policy," said Jeffrey D. Jarrett, Assistant Secretary for Fossil Energy. "It is our commitment to meet our future energy challenges and to find better ways to ensure that the United States plays a leading role in tackling climate change issues."
The NETL patents include a hybrid engine system, a process for saving energy at power plants, a method for capturing mercury from power plant flue gases, and a device to detect instability in combustion systems. The first patent law was enacted in 1790 and granted Congress the power to "promote the progress of science and useful arts."
Brief descriptions of NETL's 2006 patents follow:
- Direct Fired Reciprocating Engine and Bottoming High Temperature Fuel Cell Hybrid (6994930), from inventors Rodney A. Geisbrecht and Norman T. Holcombe
This invention is a groundbreaking new type of hybrid engine system. By reversing traditional hybrid engine systems so that the fuel cell bottoms the engine, improvements are seen in the engine's fuel efficiency, power density, and environmental performance, while the fuel cell benefits from improved startup, load following, and portability. This hybrid system is environmentally friendly, passing all engine exhaust to the fuel cell instead of releasing high concentrations of harmful emissions, and it can run on a variety of fuels such as gasoline, diesel, natural gas, and others.
- Energy Recovery During Expansion of Compressed Gas Using Power Plant Low-Quality Heat Sources (7007474), from inventors Thomas L. Ochs and William K. O'Connor
This invention capitalizes on energy that would otherwise be lost in cold compressed gas streams in power plants. Once a gas stream has been cooled and condensed, this invention uses exit cooling water from a power plant condenser (or other comparable low-quality heat source) to heat the cool high-pressure gas stream. The warmed compressed gas is then sent through an expansion engine (such as a turbine) to recover the energy. Current processes for removing pollutants and greenhouse gases from flue gas streams at power plants are significant net energy users and incur significant parasitic costs in processing the flue gas streams. The production of this extra energy will help offset processing costs and encourage the use of environmental safeguards to slow the accumulation of greenhouse gases in the atmosphere.
- Method for High Temperature Mercury Capture from Gas Streams (7033419), from inventors Evan J. Granite and Henry W. Pennline
Recognizing the need for a low-cost technique to remove mercury from coal-utilizing facilities, these inventors developed a method to absorb mercury from high- and ambient-temperature gas streams instead of emitting the mercury into the environment. The invention uses a metal sorbents to capture the trace metals mercury, arsenic, and selenium during various cycles of emissions, and it provides for potentially regenerating the sorbents in a one-step process. Because it can operate at temperatures greater than 205 degrees Celsius, the method can be used in integrated gasification combined cycle systems without disturbing their high thermal efficiency. The method will also facilitate Energy Department plans to expand the use of coal gasification over the next 20 years by mitigating the trace metals produced in the gasification process.
- Methods and Apparatus for Detecting Combustion Instability in Continuous Combustion Systems (7096722), from inventors Kelly J. Benson, Jimmy D. Thornton, George A. Richards, and Douglas L. Straub
This invention detects combustion instability even at very low levels and prevents severe damage to engine hardware. An ion sensor exposed to gases in the combustion chamber transmits signals to a control module. If volatility is detected, a signal is broadcast to indicate the onset of combustion instability. The invention is especially important for use with lean premix combustion, one of the most promising means of meeting strict environmental requirements for reducing nitrous oxide emissions in continuous combustion systems.