"Recycled Energy" engineering, design
and turn-key solutions for customers wanting to decrease their expenses
and environmental liability as well as increase their profits.
of our "Recycled Energy"
products and services include; Waste Heat Recovery,
Biomethane (or Renewable
Natural Gas) production, Waste to Energy,
Waste to Watts, and Waste
to Fuel solutions - and may may provide a return on investment in less than 12 months. We also
offer other energy-saving technologies that may include one or more of the
following; absorption chillers, cogeneration,
Side Management or other Energy
Unlike most companies, we are equipment
supplier/vendor neutral. This means we help our clients select the
best equipment for their specific application. This approach provides our
customers with superior performance, decreased operating expenses and
increased return on investment.
Our company provides turn-key project solutions that include all or part
of the following:
Engineering and Economic Feasibility
Project Design, Engineering &
Project Funding & Financing Options
Shared/Guaranteed Savings program with no
Operations & Maintenance
For more information: call us at:
Waste Heat Recovery and "Recycled Energy"sm
Many industrial processes generate large amounts of waste energy that simply pass out of plant stacks and into the atmosphere or are otherwise lost. Most industrial waste heat streams are liquid, gaseous, or a combination of the two and have temperatures from slightly above ambient to over
2000 degrees F. Stack exhaust losses are inherent in all fuel-fired processes and increase with the exhaust temperature and the amount of excess air the exhaust contains. At stack gas temperatures greater than
1000 degrees F, the heat going up the stack is likely to be the single biggest loss in the process. Above
1800 degrees F, stack losses will consume at least half of the total fuel input to the process. Yet, the energy that is recovered from waste heat streams could displace part or all of the energy input needs for a unit operation within a plant. Therefore, waste heat recovery offers a great opportunity to productively use this energy, reducing overall plant energy consumption and greenhouse gas emissions.
Waste heat recovery, also known as Recycled Energysm,
methods used with industrial process heating operations intercept the waste gases before they leave the process, extract some of the heat they contain, and recycle that heat back to the process.
Common methods of recovering heat include direct heat recovery to the process,
recuperators/regenerators, and waste heat boilers. Unfortunately, the economic benefits of waste heat recovery do not justify the cost of these systems in every application. For example, heat recovery from lower temperature waste streams (e.g., hot water or low-temperature flue gas) is thermodynamically limited. Equipment fouling, occurring during the handling of “dirty” waste streams, is another barrier to more widespread use of heat recovery systems. Innovative, affordable waste heat recovery methods that are ultra-efficient, are applicable to low-temperature streams, or are suitable for use with corrosive or “dirty” wastes could expand the number of viable applications of waste heat recovery, as well as improve the performance of existing applications.
Various Methods for Recovery of Waste Heat
Low-Temperature Waste Heat Recovery Methods – A large amount of energy in the form of medium- to low-temperature gases or low-temperature liquids (less than about
250 degrees F) is released from process heating equipment, and much of this energy is wasted.
Conversion of Low Temperature Exhaust Waste Heat – making efficient use of the low temperature waste heat generated by prime movers such as micro-turbines, IC engines, fuel cells and other electricity producing technologies. The energy content of the waste heat must be high enough to be able to operate equipment
found in cogeneration and trigeneration power and energy systems such as
absorption chillers, refrigeration applications, heat amplifiers, dehumidifiers, heat pumps for hot water, turbine inlet air cooling and other similar devices.
Conversion of Low Temperature Waste Heat into Power –The steam-Rankine cycle is the principle method used for producing electric power from high temperature fluid streams. For the conversion of low temperature heat into power, the steam-Rankine cycle may be a possibility, along with other known power cycles, such as
the organic-Rankine cycle.
Small to Medium Air-Cooled Commercial Chillers – All existing commercial chillers, whether using waste heat, steam or natural gas, are water-cooled (i.e., they must be connected to cooling towers which evaporate water into the atmosphere to aid in cooling). This requirement generally limits the market to large commercial-sized units (150 tons or larger), because of the maintenance requirements for the cooling towers. Additionally, such units consume water for cooling, limiting their application in arid regions of the U.S. No suitable small-to-medium size (15 tons to 200 tons) air-cooled absorption chillers are commercially available for these U.S. climates. A small number of prototype air-cooled absorption chillers have been developed in Japan, but they use “hardware” technology that is not suited to the hotter temperatures experienced in most locations in the United States. Although developed to work with natural gas firing, these prototype air-cooled absorption chillers would also be suited to use waste heat as the fuel.
Recovery of Waste Heat in Cogeneration and
Trigeneration Power Plants
cogeneration and trigeneration power and energy systems, the exhaust gas from the electric generation equipment is
ducted to a heat exchanger to recover the thermal energy in the gas. These heat exchangers are air-to-water heat exchangers, where
the exhaust gas flows over some form of tube and fin heat exchange surface
and the heat from the exhaust gas is transferred to make hot water or
steam. The hot water or steam is then used to provide hot water or steam
heating and/or to operate thermally activated equipment, such as an absorption
chiller for cooling or a desiccant dehumidifer for dehumidification.
Many of the waste heat recovery technologies used in building
co/trigeneration systems require hot
water, some at moderate pressures of 15 to 150 psig. In the cases where
additional steam or pressurized hot water is needed, it may be necessary
to provide supplemental heat to the exhaust gas with a duct burner.
applications air-to-air heat exchangers can be used. In other instances,
if the emissions from the generation equipment are low enough, such as is
with many of the microturbine technologies, the hot exhaust gases can be
mixed with make-up air and vented directly into the heating system for
majority of installations, a flapper damper or "diverter" is
employed to vary flow across the heat transfer surfaces of the heat
exchanger to maintain a specific design temperature of the hot water or
steam generation rate.
Waste Heat Recovery Installation
In some co/trigeneration designs, the exhaust gases can be used to activate a thermal wheel or a
desiccant dehumidifier. Thermal wheels use the exhaust gas to heat a
wheel with a medium that absorbs the heat and then transfers the heat when
the wheel is rotated into the incoming airflow.
professional engineer should be involved in designing and sizing of the
waste heat recovery section. For a proper and economical operation, the
design of the heat recovery section involves consideration of many related
factors, such as the thermal capacity of the exhaust gases, the exhaust
flow rate, the sizing and type of heat exchanger, and the desired
parameters over a various range of operating conditions of the
— all of which need to be considered for proper and economical
more information: call Monty Goodell at: 832-758-0027
* From the Department of Energy
website with permission