An anaerobic digestion plant produces two outputs, biogas and digestate, both can be further processed or utilised to produce secondary outputs. Biogas can be used for producing electricity and heat, as a natural gas substitute and also a transportation fuel. A combined heat and power plant system (CHP) not only generates power but also produces heat for in-house requirements to maintain desired temperature level in the digester during cold season. CHP systems cover a range of technologies but indicative energy outputs per m3 of biogas are approximately 1.7 kWh electricity and 2.5kWh heat. The combined production of electricity and heat is highly desirable because it displaces non-renewable energy demand elsewhere and therefore reduces the amount of carbon dioxide released into the atmosphere.
Gas is dried and vented into a CHP unit to a generator to produce electricity and heat. The size of the CHP system depends on the amount of biogas produced daily. The digested substrate is passed through screw presses for de-watering and then subjected to solar drying and conditioning to give high-quality organic fertilizer. The press water is treated in an effluent treatment plant based on activated sludge process which consists of an aeration tank and a secondary clarifier. The treated wastewater is recycled to meet in-house plant requirements. A chemical laboratory is necessary to continuously monitor important environmental parameters such as BOD, COD, VFA, pH, ammonia, C:N ratio at different locations for efficient and proper functioning of the process.
What are the Products of Photosynthesis ? - BiologyWise
determined that outdoor solar incubation for a period exceeding one month in California, resulted in an average energy conversion efficiency (energy yielded by combustion of produced hydrogen/incidence solar energy) of 0.2% (6).
Bacterial mechanisms for photosynthetic hydrogen production are summarized in Figure 2-4.
Primary Productivity & Dissolved Oxygen Lab - …
More than being helpful, it is a necessity for humans and other animal species which can't produce their own food, but instead rely on the products of this process to meet their energy requirements and for the process of respiration.
LabBench Activity Dissolved Oxygen and Aquatic Primary Productivity
Anaerobic digestion plants not only decrease GHGs emission but also reduce dependence on fossil fuels for energy requirements. The anaerobic process has several advantages over other methods of waste treatment. Most significantly, it is able to accommodate relatively high rates of organic loading. With increasing use of anaerobic technology for treating various process streams, it is expected that industries would become more economically competitive because of their more judicious use of natural resources. Therefore, anaerobic digestion technology is almost certainly assured of increased usage in the future.