Animal Waste to Energy
Everyone’s focus seems to be on reducing carbon dioxide emissions these days, to combat global warming. But turning animal waste to energy could turn millions of pounds of cow manure and other animal waste into a renewable energy source. Animal waste that is currently releasing nitrous oxide – a GHG that warms the atmosphere over 300 times more than carbon dioxide.
An anaerobic digester takes animal waste and turns it into energy, such as nitrous oxide and methane which can be burned as fuel to produce electricity with the help of a turbine generator.
Science Daily writes more on animal waste to energy in their article, Cow Power Could Generate Electricity for Millions.
Texas: At an Energy Crossroads
Black Gold
Ever since the first oil well gushed forth in East Texas in 1866, Texas has been renowned for its “black gold.” An oil-related economy developed around subsequent oil discoveries as the state prospered with its flourishing petroleum industry. Throughout most of the first half of the century, oil was plentiful, prices were low and most of the world’s oil was produced and consumed in the U.S. At mid-century, Texas was the dominant producer in the world oil market, producing more oil than the entire output of the Middle East. From its oil and gas revenues, the state has collected billions of dollars in taxes that have built some of the nation’s best roads, schools and infrastructure.
Crossroads
Until 1972 it seemed that Texas oil would never run out, but in that year Texas oil production peaked and began a decline in both reserves and production until, today, Texas has become a net energy importer. With uncanny timing, the OPEC Oil Embarg hit in 1973. Concurrent with the oil decline, Americans were witnessing long lines of cars waiting to fill up at shocking gasoline prices. It was a major turning point in the world oil market — and a wake-up call. Along with the rest of the nation, Texas is taking a hard look at its energy scenario in terms of developing a stable, clean and plentiful energy future. Texas is at a crossroads wherein development of vast in-state renewable energy sources, coupled with energy efficiency measures, offers Texans the chance to redirect their focus in order to regain and maintain their energy independence.
Texas has more renewable energy potential than any other state, ranking first in practically all categories. Already equipped with expertise and resources in the area of energy production, Texas can recapture its former energy independence by shifting focus to renewable energy. Not only would such a move cut down on our growing dependence on oil imports, it would also spur the Texas economy, create jobs, increase our tax base and clean up our air.
Texas has more renewable energy potential than any other state.
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| Texas is beginning to shift focus to its vast renewable and clean energy resources. |
Declining Costs of Renewable Energy
The cost of energy from renewable technologies has steadily declined in the past quarter century. As an example, the cost of wind energy has declined from about 30-45 cents per kilowatt-hour in 1980 to less than 5 cents today. Wind, PV, geothermal, solar thermal, and biomass have all seen significant drops in cost with the improvements in technology.
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| It makes economic sense for Texas to tap into its vast renewable reserves. With declining costs, renewable energy sources are becoming more competitive with fossil fuels. |
Cost Curves
This DOE PowerPoint presentation shows historical renewable energy cost trends with projections through 2020.
Texas Fuel Demands
Although home to just eight percent of the U.S. population, Texas uses more electricity, natural gas, coal and oil than any other state; and demand is increasing, particularly for electricity. This fact is significant because new energy facilities, renewable or otherwise, will be constructed most rapidly in the context of a large, growing energy economy. The demand is there, the resources are there, and Texas is proving that it has the motivation and expertise to develop the requisite infrastructure to harvest these natural resources.
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| Texas Railroad Commission interpretation of U. S. Department of energy data. |
Texas Infrastructure — Making the Switch
As one of the major energy production and consumption centers in the world, Texas has extensive energy infrastructure already in place. The early Texas oil fields served as fertile ground for the growth of numerous supports numerous industries from heavy equipment fabricators to oilfield service providers and fire control experts to specialized petroleum landmen and lawyers. In many cases, members of these fledgling groups have come to be recognized as the world’s most knowledgeable and capable experts in their fields.
The Permian Basin, Texas Panhandle and Texas/Louisiana Gulf Coast are among the largest gathering regions and transportation hubs for pipeline gas in North America. Even though competition for access to available energy transportation infrastructure poses a near-term challenge for renewable energy projects, it also represents a considerable long-term opportunity. As it becomes increasingly difficult to construct new energy transmission projects, existing energy infrastructure and transmission right-of-ways may prove to be a strategic asset that benefits Texas renewables. Hydrogen generated by solar plants in the Permian Basin, wind plants in the Panhandle and geopressure facilities along the Gulf Coast, could someday trace the same routes currently used by Texas natural gas to reach markets across North America.
Unique Factors – Unique Opportunity
Texas, perhaps more than any other state, stands to benefit from the rapid development of renewables. Several factors position Texas favorably to pioneer the widespread use of renewable energy resources:
Texas has high total renewable energy resource potential. Texas ranks first nationally in practically all renewable energy resource categories (number one for solar and biomass; number two for wind).
Texas has high current and projected energy needs. Ironically this is a plus for Texas, for although abundant availability of a resource is a prerequisite to widespread use, development of any resource is strictly limited by the demand for it. As demand is growing, so is the scramble to find alternative ways to supply the growing energy needs of Texans.
Texas has considerable existing energy infrastructure. Texas already has an existing energy infrastructure, as discussed in the previous section on Texas Expertise.
Texas is strategically located relative to Latin American markets. Growing demand in Latin America for raw energy, energy technology and services represents opportunity for all Texas energy enterprises. Texas’ physical proximity to and prominence with Mexico, Central America and South America must be considered a strategic advantage for trade with those regions. Furthermore, 60% of the electrical interconnection points and 75% of the major gas pipelines between the U. S. and Mexico meet at the Texas border.
| Texas Wildcatters |
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Texans have a rich and colorful past in mining nature’s energy resources, of seizing the moment when opportunity is promising but uncertain. Wildcatters were after oil, they knew it was there, but where exactly? They risked everything to find a “wildcat,” an oil gusher as yet unexplored and unclaimed. What began with wildcatter foresight ended with the Texas oil boom?
Enlightened by the rich history of the Texas oil industry, Texans now have the opportunity to recapture that “wildcatter” experience and capitalize on the enduring benefits possible from nurturing a vibrant domestic renewable energy industry through the early development of the state’s vast renewable resources.
Although hydropower and biomass have long contributed to our nation’s energy mix, the renewable energy industry is in its early stages of development. Wind and solar technologies, in particular, are seemingly on the verge of capturing a significant share of new energy markets. If renewable energy sources emerge as a dominant contributor to future energy markets, economics benefits will accrue to those regions that pioneer the development of successful renewable energy technologies.
When decision makers contemplate priorities for investing in the development of renewable resources, Texas offers a logical proving ground with superior potential for high return on investment. Texas is well positioned to reap the benefits from the early development of renewable resources and the continued development of the infrastructure to service and market these resources.
Renewable Energy Basics
The United States currently relies heavily on coal, oil, and natural gas for its energy. Fossil fuels are nonrenewable, that is, they draw on finite resources that will eventually dwindle, becoming too expensive or too environmentally damaging to retrieve. In contrast, renewable energy resources—such as wind and solar energy—are constantly replenished and will never run out.
Most renewable energy comes either directly or indirectly from the sun. Sunlight, or solar energy, can be used directly for heating and lighting homes and other buildings, for generating electricity, and for hot water heating, solar cooling, and a variety of commercial and industrial uses.
The sun’s heat also drives the winds, whose energy is captured with wind turbines. Then, the winds and the sun’s heat cause water to evaporate. When this water vapor turns into rain or snow and flows downhill into rivers or streams, its energy can be captured using hydropower.
Along with the rain and snow, sunlight causes plants to grow. The organic matter that makes up those plants is known as biomass. Biomass can be used to produce electricity, transportation fuels, or chemicals. The use of biomass for any of these purposes is called biomass energy.
Hydrogen also can be found in many organic compounds, as well as water. It’s the most abundant element on the Earth. But it doesn’t occur naturally as a gas. It’s always combined with other elements, such as with oxygen to make water. Once separated from another element, hydrogen can be burned as a fuel or converted into electricity.
Not all renewable energy resources come from the sun. Geothermal energy taps the Earth’s internal heat for a variety of uses, including electric power production, and the heating and cooling of buildings. And the energy of the ocean’s tides comes from the gravitational pull of the moon and the sun upon the Earth.
In fact, ocean energy comes from a number of sources. In addition to tidal energy, there’s the energy of the ocean’s waves, which are driven by both the tides and the winds. The sun also warms the surface of the ocean more than the ocean depths, creating a temperature difference that can be used as an energy source. All these forms of ocean energy can be used to produce electricity.
Renewable energy provides many important benefits including:
Environmental Benefits
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| The U.S. Fish and Wildlife service uses a photovoltaic system to provide clean energy at the Farallon National Wildlife Refuge. |
Renewable energy technologies are a lot friendlier to the environment than conventional energy technologies, which rely on fossil fuels. Fossil fuels contribute significantly to many of the environmental problems we face today—greenhouse gases, air pollution, and water and soil contamination—while renewable energy sources contribute very little or not at all.
Greenhouse gases—carbon dioxide, methane, nitrous oxide, hydrocarbons, and chlorofluorocarbons—surround the Earth’s atmosphere like a clear thermal blanket, allowing the sun’s warming rays in and trapping the heat close to the Earth’s surface. This natural greenhouse effect keeps the Earth’s average surface temperature at about 60°F (33°C). But the increased use of fossil fuels has significantly increased greenhouse gas emissions, particularly carbon dioxide, creating an enhanced greenhouse effect known as global warming. According to the U.S. Environmental Protection Agency (EPA), carbon dioxide is responsible for one-half to two-thirds of our contribution to global warming. Renewable energy technologies, however, can produce heat and electricity with a very low or no amount of carbon dioxide emissions.
Energy use from fossil fuels is also a primary source of air, water, and soil pollution. Pollutants—such as carbon monoxide, sulfur dioxide, nitrogen dioxide, particulate matter, and lead—take a dramatic toll on our environment. On the other hand, most renewable energy technologies produce little or no pollution.
Both pollution and global warming pose major health risks to humans. According to the American Lung Association, air pollution contributes to lung disease — including asthma, lung cancer, and respiratory tract infections — and close to 335,000 people in the United States die from it every year. Meanwhile, the long-term effects associated with global warming may be even more devastating. Deaths due to extreme weather could increase, and diseases could have a greater potential to thrive as temperatures rise.
Ultimately, renewable energy technologies could help us break our conventional pattern of energy use to improve the quality of our environment.
Energy for the Future
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| This cornfield can be used to make ethanol—a fuel we won’t run out of as long we grow corn and other comparable plants. |
What will the world’s energy use be like in the future? Well, we can be pretty certain that electricity use will grow worldwide. The International Energy Agency projects that the world’s electrical generating capacity will increase to nearly 5.8 million megawatts by the year 2020, up from about 3.3 million in 2000. However, the world supplies of fossil fuels—our current main source of electricity—will start to run out from the years 2020 to 2060, according to the petroleum industry’s best analysts. How will we meet those electricity needs? Our best answer could be renewable energy.
Shell International predicts that renewable energy will supply 60% of the world’s energy by 2060. The World Bank estimates that the global market for solar electricity will reach $4 trillion in about 30 years. Biomass fuels could also replace gasoline. It is estimated that the United States could produce 190 billion gallons per year of ethanol using available biomass resources in this country.
And unlike fossil fuels, renewable energy sources are sustainable. They will never run out. According to the World Commission on Environment and Development, sustainability is the concept of meeting “the needs of the present without compromising the ability of future generations to meet their own needs.” That means our actions today to use renewable energy technologies will not only benefit us now, but will benefit many generations to come.
Jobs and the Economy
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| A certification test engineer, shown here measuring the noise from a wind turbine, is one of many careers available in the renewables industry. |
Many U.S. communities have to import fossil fuels, such as oil and natural gas, to provide electricity, heating, and fuel. The cost of these fossil fuels can add up to billions of dollars. And every dollar spent on energy imports is a dollar that the local economy loses. Renewable energy resources, however, are developed locally. The dollars spent on energy stay at home, creating more jobs and fostering economic growth.
Renewable energy technologies are labor intensive. Jobs evolve directly from the manufacture, design, installation, servicing, and marketing of renewable energy products. Jobs even arise indirectly from businesses that supply renewable energy companies with raw materials, transportation, equipment, and professional services, such as accounting and clerical services.
In turn, the wages and salaries generated from these jobs provide additional income in the local economy. Renewable energy companies also contribute more tax revenue locally than conventional energy sources.
The economic advantages of renewable energy also extend far beyond the local economy. The whole country benefits. In 2001, the United States spent about $103 billion dollars outside the country for oil. But as one of the world’s leading manufacturers of renewable energy systems, we can bring in more money with the increased use of renewable energy sources around the world. Currently, for example, the United States manufactures about two-thirds of the world’s photovoltaic (PV) systems. And it exports about 70% of these PV systems, mostly to developing nations, resulting in annual sales of more than $300 million.
Energy Security
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| NREL’s Solar Independence Exhibit featured a 4-kilowatt photovoltaic system that is used for mobile emergency power. |
Our nation’s energy security continues to be threatened by our dependency on fossil fuels. These conventional energy sources are vulnerable to political instabilities, trade disputes, embargoes, and other disruptions.
U.S. domestic oil production has been declining since 1970. In 1973, the United States only imported about 34% of its oil. Today, our country imports more than 53%, and it is estimated that this could increase to 75% by 2010.
Most of the world’s oil reserves are now in the Middle East. We have witnessed this shift in economic influence through the last three sharp increases in the world’s oil prices: the Arab Oil Embargo in 1974, the Iranian Oil Embargo in 1979, and the Persian Gulf War in 1990. It has resulted in periods of negative economic growth and a rising trade deficit.
But with renewable energy, we can decrease our dependency on foreign oil imports. For example, the U.S. Department of Energy (DOE) estimates that if we displace 10% of our petroleum use for transportation with biofuels, which are produced from organic material, we could save about $15 billion over 10 years. A 20% displacement could save us about $50 billion. This would strengthen our energy security, as well as our economic and national security.
Waste Heat Recovery
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 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
In most 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.
In some 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 building heating.
In the 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.
| Typical Waste Heat Recovery Installation |
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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.
A 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 co/trigeneration system — all of which need to be considered for proper and economical operation.
Publicly Owned Treatment Works Waste Recovery Systems
More and more, cities, counties and municipalities are faced with greater environmental compliance issues relating to their municipally-owned landfills, Publicly Owned Treatment Works (“POTW’s”) or Wastewater Treatment Systems. Publicly Owned Treatment Works Waste Recovery Systems
A city’s landfill and/or POTW provide an excellent opportunity for cities to reduce their emissions as well as provide an additional revenue stream. These facilities may have valuable gases that our company recovers and pipes to one of our clean, environmentally-friendly cogeneration or trigeneration energy systems.
Our company provides economic and ecological solutions for cities and municipalities and provide a new cash flow simultaneously. We offer turn-key solutions for cities that includes the preliminary feasibility analysis, engineering and design, project management, permitting and commissioning. We provide very attractive financing packages for cities that do not add to a city’s liability, yet provide a valuable new revenue stream. And, we are also able to offer a turn-key solution for qualified municipalities that includes our company owning, operating and maintaining the onsite power and energy plant.
At the heart of the system is a (Bio) Methane Gas Recovery system similar those used in Flare Gas Recovery or Vapor Recovery Units. Methane Gas Recovery, Flare Gas Recovery, Vapor Recovery, Waste to Energy and Vapor Recovery Units all recover valuable “waste” or vented fuels that can be used to provide fuel for an onsite power generation plant. Our waste-to-energy and waste to fuel systems significantly or entirely, reduces your facility’s emissions (such as NOx , SOx, H2S, CO , CO2 and other Hazardous Air Pollutants/Greenhouse Gases) and convert these valuable emissions from an environmental problem into a new cash revenue stream and profit center.
Methane Gas Recovery and vapor recovery units can be located in hundreds of applications and locations. At a landfill, Wastewaster Treatment System (or Publicly Owned Treatment Works – “POTW”) gases from the facility can be captured from the anaerobic digesters, and manifolded/piped to one of our onsite power generation plants, and make, essentially, “free” electricity for your facility’s use. These associated “biogases” that are generated from municipally owned landfills or wastewater treatment plants have low btu content or heating values, ranging around 550-650 btu’s. This makes them unsuitable for use in natural gas applications. When burned as fuel to generate electricity, however, these gases become a valuable source of “renewable” power and energy for the facility’s use or resale to the electric grid.
Additionally, if heat (steam and/or hot water) is required, we will incorporate our cogeneration or trigeneration system into the project and provide some, or all, of your hot water/steam requirements. Similarly, at crude oil refineries, gas processing plants, exploration and production sites, and gasoline storage/tank farm site, we convert your facility’s “waste fuel” and environmental liabilities into profitable, environmentally-friendly solutions.
Our Methane Gas Recovery systems are designed and engineered for these specific applications. It is important to note that there are many internal combustion engines or combustion turbines that are NOT suited for these applications. Our systems are engineered precisely for your facility’s application, and our engineers know the engines and turbines that will work as well as those that don’t. More importantly, we are vendor and supplier neutral! Our only concerns are for the optimum system solution for your company, and we look past brand names and sales propaganda to determine the optimum system, which may incorporate either one or more; gas engine genset(s) or gas turbine genset(s), in cogeneration or trigeneration mode – in trigeneration mode, we incorporate absorption chillers to make chilled water for process or air-conditioning, fuel gas conditioning equipment and gas compressor(s).
Our turn-key systems include design, engineering, permitting, project management, commissioning, as well as financing for our qualified customers. Additionally, we may be interested in owning and operating the flare gas recovery or vapor recovery units. For these applications, there is no investment required from the customer.
For more information, please provide us with the following information about the flare gas or vapor:
- Type of gas being flared or vented (methane, bio-gas, digester, landfill, etc.).
- Chromatograph Fuel/Gas analysis which provides us with the btu’s (heating value) and the composition of the gas and its’ impurities such as methane (and the percentage of methane), soloxanes, carbon dioxide, hydrogen, hydrogen sulfide, and any other hydrocarbons.
- Total amount of gas available, from all sources, at the facility.
What is BioMethane and BioMethanation?
BioMethane is a renewable energy/fuel, with properties similar to natural gas, produced from “biomass.” Unlike natural gas, BioMethane is a renewable energy.
The cost of producing BioMethane, after installation of the BioMass Gasification equipment used to produce BioMethane (the process of making BioMethane is called “BioMethanation”) is called is essentially free.
Again, unlike the price of natural gas, which has been around $6.00/mmbtu for the past year.
More About Biomass Gasification and BioMethanation Technology
The process of Biomass Gasification produces BioMethane. BioMethane is also produced in anaerobic digesters, in the process called anaerobic digestion. BioMethane is a renewable energy resource, as opposed to natural gas (methane), which is a non-renewable energy resource. BioMethane has similar qualities of methane and both are used in interchangeably, and each may be a substitute for the other.
The production and disposal of large quantities of organic and biodegradable waste without adequate or proper treatment results in widespread environmental pollution. Some waste streams can be treated by conventional methods like aeration. Compared to the aerobic method, the use of anaerobic digesters in processing these waste streams provides greater economic and environmental benefits and advantages.
As previously stated, Biomethanation is the process of conversion of organic matter in the waste (liquid or solid) to BioMethane (sometimes referred to as “BioGas) and manure by microbial action in the absence of air, known as “anaerobic digestion.”
Conventional digesters such as sludge digesters and anaerobic CSTR (Continuous Stirred Tank Reactors) have been used for many decades in sewage treatment plants for stabilizing the activated sludge and sewage solids.
Interest in BioMethanation as an economic, environmental and energy-saving waste treatment continues to gain greater interest world-wide and has led to the development of a range of anaerobic reactor designs. These high-rate, high-efficiency anaerobic digesters are also referred to as “retained biomass reactors” since they are based on the concept of retaining viable biomass by sludge immobilization.
Biomass Gasification and the Production of BioMethane
Biomass is a renewable energy resource which includes a wide variety of organic resources. A few of these include wood, agricultural residue/waste, and animal manure.
Biomass Gasification is the process in which BioMethane is produced in the BioMass Gasification process. The BioMethane is then used like any other fuel, such as natural gas, which is not a renewable fuel.
Historically, biomass use has been characterized by low btu and low efficiencies. However, today biomass gasification is gaining world-wide recognition and favor due to the economic and environmental benefits. In terms of economic benefits, the cost of the BioMethane is essentially free, after the cost of the equipment is installed. BioMethane, probably the most important and efficient energy-conversion technology for a wide variety of biomass fuels. The large-scale deployment of efficient technology along with interventions to enhance the sustainable supply of biomass fuels can transform the energy supply situation in rural areas. It has the potential to become the growth engine for rural development in the country.
Principles of Biomass Gasification
Biomass fuels such as firewood and agriculture-generated residues and wastes are generally organic. They contain carbon, hydrogen, and oxygen along with some moisture. Under controlled conditions, characterized by low oxygen supply and high temperatures, most biomass materials can be converted into a gaseous fuel known as producer gas, which consists of carbon monoxide, hydrogen, carbon dioxide, methane and nitrogen. This thermo-chemical conversion of solid biomass into gaseous fuel is called biomass gasification. The producer gas so produced has low a calorific value (1000-1200 Kcal/Nm3), but can be burnt with a high efficiency and a good degree of control without emitting smoke. Each kilogram of air-dry biomass (10% moisture content) yields about 2.5 Nm3 of producer gas. In energy terms, the conversion efficiency of the gasification process is in the range of 60%-70%.
Multiple Advantages of Biomass Gasification in Methane Production
Conversion of solid biomass into combustible gas has all the advantages associated with using gaseous and liquid fuels such as clean combustion, compact burning equipment, high thermal efficiency and a good degree of control. In locations, where biomass is already available at reasonable low prices (e.g. rice mills) or in industries using fuel wood, gasifier systems offer definite economic advantages. Biomass gasification technology is also environment-friendly, because of the firewood savings and reduction in CO2 emissions.
Biomass gasification technology has the potential to replace diesel and other petroleum products in several applications, foreign exchange.
Applications for Biomass Gasification
Thermal applications: cooking, water boiling, steam generation, drying etc. Motive power applications: Using producer gas as a fuel in IC engines for applications such as water pumping Electricity generation: Using producer gas in dual-fuel mode in diesel engines/as the only fuel in spark ignition engines/in gas turbines.
