In our increasingly populated world, waste is unavoidable. But instead of just letting it rot, now we can put it to work in ways that actually help the environment and fuel your business at the same time.
Landfill gas is created during the anaerobic decomposition of organic substances in municipal solid waste (MSW) and commercial and industrial (C&I) wastes. Depending upon the landfill design and its management, as well as waste composition, compaction, moisture and several other factors, thousands of landfills are available worldwide to collect and utilise this valuable renewable energy source for power generation. If landfill gas is allowed to escape to atmosphere, methane contained within it is a powerful greenhouse gas, 21 times more so than carbon dioxide. Therefore, its prevention of escape to atmosphere and its utilisation as a renewable fuel source is a win-win situation.
Landfill Gas Collection For a landfill restoration that prevents greenhouse gas from migrating into the atmosphere while avoiding offensive smells and smoldering fires, the gas must be continuously extracted under controlled conditions. Perforated tubes are drilled into the landfill body and interconnected by a pipework system. Using a blower, the gas is sucked from the landfill. A well-designed gas collection system will flexibly capture the gas from various spots and handful high temperatures, leachate, condensates and air content – thus ensuring a cost-efficient collection as well as stable gas quality. Several engineering companies specialise in this field and offer their services on a worldwide basis.
Landfill Gas Composition Landfill gas composition and production rates are primarily affected by the waste that has been deposited in the landfill site. MSW contains 150-250 kg of organic carbon per tonne which micro-organisms convert to landfill gas via anaerobic processes. The gas formation is influenced by a number of factors such as waste composition, landfill storage height and density, air temperature, atmospheric pressure and precipitation levels. Gas production starts one to two years after the waste is deposited in the landfill and lasts 15-25 years. The continuously decreasing gas volume can be compensated by the disposal of additional waste during this period. With a calorific value of 3.5 to 5.5 kWh Nm3(35-55% methane), landfill gas constitutes a high-value fuel for gas engines that can be effectively used for power generation.
| Component | Composition (by volume) |
| Methane (CH4) | 35-55% |
| Carbon dioxide (CO2) | 30-44% |
| Nitrogen (N2) | 5-25% |
| Oxygen (O2) | 0-6% |
| Water vapour | Saturated |
Consequently, 1 million tonnes of MSW generate 1.7-2.5 million m3 of collectable methane, enough to fuel a gas engine capacity of 850-1,250 kWeproducing 6,500 to 10,000 MWh of electricity per year. That roughly corresponds to the average power demand of 1,500-2,200 EU households.
The Jenbacher Concept The broad range of Jenbacher landfill gas engines is specifically designed to run at full load with high efficiency and high availability, despite a low heating value and fluctuating gas quality and pressure. The high quality and specially designed engine parts resist the impurities that usually appear in this type of fuel. Before the landfill gas can be fed into the gas engines, it needs to be dried and compressed. Severe contaminants such as siloxanes should be removed if exceeding a certain level. Not only will these measures considerably increase the availability of the generator, but they will also reduce the costs associated with operation. Since landfills are usually located near big cities, emission standards are becoming more and more ridged in many countries. To comply with these standards, the whole system must be managed, beginning with the fuel gas conditions up to the installation of an exhaust treatment service.
Advantages ● Smooth operation despite low heating value and fluctuations in gas composition and pressure.
● Electrical efficiency of up to 42%, and up to 90% efficiency in the case of combined heat and power.
● Low weight
containerised units that are easy to move and adjust to changing project capacity.
● Basic design and support for gas conditioning, if required.
● TSA: In-house gas cleaning unit in case of high siloxane load in landfill gas
●
CL.AIR: Integrated exhaust after-treatment solution complying with country-specific standards
● Flexible Contractual Service Agreements
● Alternative disposal of a problem gas while simultaneously harnessing it as an energy source
● Revenues for power and heat production when fed into the public grid.
● Carbon credits for reduction of methane releases or special renewable energy tariffs
Our Competence Topkapı Endüstri has installed and commissioned over 160 MW of landfill gas generation equipment in Turkey and is one of the leading players in its field. Globally Jenbacher units are applied in over 1,400 landfill gas systems with a total output of approximately 1,400MW. Topkapı Endüstri and Jenbacher product teams offer an unparalleled breadth of expertise, references and solutions.
Please click for some of Landfill gas references in Turkey.
If you would like to discuss your greenhouse cogeneration project in more depth, please contact us.
-
Landfillgas - Brochure
