Our company is committed to assist India become Energy Self sufficient through sustainable sources for generation of Electricity.
We bring in a rich experience of installing and commissioning over 100 Biogas run Electric Power Generation plants all over Europe and also in the US. Biogas Energy is Green Energy. These plants range in capacity from 0.2 MW to 4 MW.
These plants use biodegradable wastes from Agriculture, Industry, Human, Animal, Land-fill, etc as the source input. We also have a break-through technology in using waste water discharges from Industries, Sewage, swamp etc. as the input source.
Anaerobic Digesters [Biomass gasifiers] recover valuable and toxic Biomethane from organic materials used as a renewable fuel for cogeneration and tri-generation power plants. Biomethanation is the process of conversion of organic matter in the waste (liquid or solid) to Biomethane which is commonly referred as “Biogas” and manure by microbial action in the absence of air, known as "anaerobic digestion."
The key processes of Anaerobic Digestion are:
Biomass gasifiers are reactors that heat biomass in a low-oxygen environment to produce a fuel gas. Biomethane is 98% methane. Methanogenesis is the production of CH4 and CO2 by biological processes that are carried out by methanogens. This gas produced from gasifiers can drive highly efficient devices such as turbines and fuel cells to generate electricity.
Biogas (BioMethane), after installation of the biomethane equipment is essentially free.
Electricity generation with waste heat recovery (cogeneration) and direct combustion and use in equipment that normally uses propane or natural gas are the two primary options for biogas utilization. Electricity generated using biogas can be generated for on-farm use or for sale to the electric power grid if an economically attractive power purchase agreement can be negotiated through the local utility or rural electric cooperative. Direct combustion allows the gas to be used in existing equipment that normally uses propane or natural gas such as boilers or forced air furnaces with minor equipment modifications.
Stirling engine capable of producing electricity from biomass combustion heat
Commercial electricity generation systems that use biogas typically consist of an internal combustion (IC) engine, a generator, a control system and an optional heat recovery system. IC engines designed to burn propane or natural gas are converted to burn biogas by adjusting carburation and ignition systems. Such engines are available in nearly any capacity, but the most successful varieties are industrial engines that are designed to work with wellhead natural gas. A biogas-fueled engine will normally convert 18 to 25 percent of the biogas Btu value to electricity.
Two types of generators are used: induction generators and synchronous generators. Induction generators operate in parallel with the utility and cannot operate as a stand-alone power source. Induction generators derive their phase, frequency and voltage from the utility. Synchronous generators operate as an isolated system or in parallel to the utility, and require more sophisticated intertie systems to match output to utility phase, frequency and voltage.
Control systems are required to protect the engine and the utility. Control packages are available that can shut the engine off due to mechanical problems, utility power outage or utility voltage and frequency fluctuations, or in the event that excess power is generated that the utility will not accept. Generators that operate in parallel with the utility system, such as induction generators, require an intertie system with safety relays to shut off the engine and disconnect from the utility in the event of a problem. Intertie negotiations with a utility for induction generators are typically much easier than for a synchronous generator, due to the level of control the utility has over the characteristics of power entering the grid from an induction generator. The primary advantage of a synchronous generator is its ability to act as a stand-alone power source. However, if operated as an isolated system, a synchronous generator must be oversized to meet the highest electrical demand, while operating less efficiently at average or partial loads. Due to the system size and more complicated control requirements, a synchronous generator operating as an isolated system is typically more expensive than an induction generator.
Biogas engines reject approximately 75 to 82 percent of the energy input as waste heat. This waste heat can be used to heat the digester and/or provide water or space heat to the facility. Commercial heat exchangers can recover waste heat from the engine water cooling system and the engine exhaust, recovering up to 7,000 Btu/hour for each kW of generator load. Waste heat recovery increases the energy efficiency of the system to 40 to 50 percent.
Organic Manure as a by-product
What happens to the residue of the wastes after Methanogenesis?
Digestate is the solid remnants of the original input material to the digesters that the microbes cannot use. It also consists of the mineralised remains of the dead bacteria from within the digesters. Digestate can come in three forms; fibrous, liquor or a sludge-based combination of the two fractions. In two-stage systems the different forms of digestate come from different digestion tanks. In single stage digestion systems the two fractions will be combined and if desired separated by further processing
Acidogenic anaerobic digestate
The second by-product (acidogenic digestate) is a stable organic material comprised largely of lignin and cellulose, but also of a variety of mineral components in a matrix of dead bacterial cells; some plastic may be present. The material resembles domestic compost and can be used as compost or to make low grade building products such as fibreboard
The third by-product is a liquid (methanogenic digestate) that is rich in nutrients and can be used as a fertiliser dependent on the quality of the material being digested. Levels of potentially toxic elements (PTEs) should be chemically assessed. This will be dependent upon the quality of the original feedstock. In the case of most clean and source-separated biodegradable waste streams the levels of PTEs will be low. In the case of wastes originating from industry the levels of PTEs may be higher and will need to be taken into consideration when determining a suitable end use for the material.
Digestate typically contains elements such as lignin that cannot be broken down by the anaerobic microorganisms. Also the digestate may contain ammonia that is phytotoxic and will hamper the growth of plants if it is used as a soil improving material. For these two reasons maturation or composting stage may be employed after digestion. Lignin and other materials are available for degradation by aerobic microorganisms such as fungi helping reduce the overall volume of the material for transport. During this maturation the ammonia will be broken down into nitrates, improving the fertility of the material and making it more suitable as a soil improver. Large composting stages are typically used by dry anaerobic digestion technologies.