Research
Research works include diagnosing the pattern of energy use at farm and agro industrial level and identifying the needs and gaps to substitute renewable energy and conserve fossil fuels. This taken care of by formulating and conducting suitable research projects/wherever needed. Modifying the existing energy gadgets for various applications in the farm or agro-industry and in formulating research programmes, relative priorities are given to small, medium and large-scale agro-industries and allied utilities. Priorities are given to home, farm and agro-industries in view of the prospects of renewable energy technology applications in these sectors.
Technologies developed
The important technologies generated in this department by the scientist and students and released in our university so far are as follows.
TNAU fixed dome type biogas plant
The cost of the biogas plant is cheaper by 50% compared to the conventional KVIC model biogas plant. There is a good response from the farming communities for the adoption of TNAU fixed dome type biogas plant. The Govt. of India has also made the TNAU fixed dome type biogas plant for getting the central subsidy under the National project on Biogas Development and so far more than 2.00 lakh plants have been installed.
Fibre reinforced plastic (FRP) drum
In order to avoid the corrosion problem, the drum was replaced with fibre reinforced plastic drum with proper weight addition arrangement. The life of the plant is increased from 4-5 years to 15 years More than 30,000 units have been installed in Tamil Nadu.
Low cost biogas burner
The cost of burner was reduced by 60% to popularize among small and marginal farmers. There is good response for these burners form the farmers and more than 2500 farmers have adopted it.
Biogas balloon
In order to store the biogas for running the engine, a simple device as biogas balloon was designed, developed and released for the benefit of industries.
Biogas operated brooder
In order to reduce of cost of electricity for the poultry industries, biogas produced from poultry waste was utilized to operate the brooder at a cheaper rate. More than 10 industries have benefited from these units.
TNAU Sakthi Biogas plant
In order to reduce the area required for the construction of biogas plant and also to reduce the cost, the TNAU Sakthi model biogas plant was designed, developed and released. More than 100 plants have been installed so far.
Biogas cum Solar Powered Light Trap
In order to collect and kill the insects, a biogas cum solar powered light trap has been designed, developed and released which can be operated either by biogas or solar energy. Five farmers have adopted this devices
Biomass gas stove
This stove widens the market for agro wastes, makes possible a higher efficiency and reduces the time. Now installed in more than 200 places.
Community chulha
It is exclusively design and developed to Cates the needs of noon meal centres. It is efficient, smokeless and conserves feedstock.
Renewable Energy Park
Gadgets developed at the Department of Bio Energy since 1982 are displayed in the. More than 10000 people visited and appreciated the Park.
Rice husk gasifiier
It can be used for thermal applications in agro industries particularly in Rice Mills. Its thermal efficiency is 55 – 60%.
Wood based gasifier
It is designed to generate producer gas from wood wastes. Fast growing species such as Acacia, Prosopis and Casuarina can be successfully used as feedstock.
Thermal output: 50000 kal/h
Capacity: 20 kw
Wood consumption: 20-25 kg/h
Thermal applications for medium scale industries
Pilot plant for biodiesel
It is designed to produce Biodiesel from Jatropha oil. The biodiesel production unit consists of a vessel with heater, a stirrer, a container where chemical and oil are mixed, settling tanks and finally a washing tank. The developed unit can esterify 250 litres of biodiesel per day. Depending upon the need, the size of the unit can be scaled up to get higher production capacity.
Efficiency: 99% conversion efficiency
Cost: 1.5 lakhs
Biomass hot air generation system integrated with Solar tunnel dryer
A continuous auto controlled drying system with combination of solar and biomass as heat source for drying various agricultural products at temperature of 60°C. This hybrid dryer facilitates drying during sunshine and off sunshine hours with enhanced quality of dried products
Drying Capacity: 2 Tonnes/batch
Drying time: 48 h for coconut
Payback period: 3.5 years
15.Night soil biogas plant of 20 m3 capacity
The anaerobic digestion of human excreta produces biogas and also reduces pathogens in the excreta and its unwanted odour and environmental degradation. The biogas production from human excreta is a boon towards safe and hygienic disposal of excreta. The moisture content of the night soil is about 90 % of the total weight with the total solids accounting about 10 %. The volatile solids accounted for about 90% of the total solids. The carbon content, nitrogen content, total potassium and total phosphorus content are in the range of 40-45, 6-7.5, 1-2 and 4-6%, respectively. Biogas produced from night soil biogas plant is used for cooking and by this plant, nearly 10 to 12 LPG gas cylinders has been saved per month.
Pyrolytic reactor for biochar production
The biochar unit developed has a capacity of 2 kg and it is highly portable in terms of size and weight. The energy efficiency of the unit is very high (71%) compared to (40%) in traditional systems. This system was evaluated for biochar production and its capacity for carbon sequestration, a measure to mitigate global warming.
Biocoal production from lignocellulosic biomass
An energy efficient high pressure hydrothermal carbonization unit of 1 L capacity has been developed to produce bio-coal from lignocellulosic biomass materials. Calorific value of bio-coal has been estimated as 25 MJ kg-1. The produced bio-coal has been proved to be promising, sustainable, energy efficient and eco-friendly solid fuel.
Tar cracking gasifier
The removal of tar and particulates has mostly been practiced as a secondary measure with downstream of the gasifier system in India. For the first time a gasifier system using primary method for the cracking of tar has been developed. This helps in achieving the prescribed limits of tar and particulate matter when coupled with a secondary system. Primary tar cracking proved to be an effective method for tar elimination in producer gas with 83% cracking efficiency. This also leads to the production of hydrogen rich gas.
Hydrothermal liquefaction reactor for biocrude oil production
Hydrothermal liquefaction (HTL) process converts waste wet biomass into a liquid fuel called biocrude. In this conversion process, elevated temperature (200–350ºC) and pressure (5–15 MPa) are used to breakdown and reform biomass macromolecules into biofuel called biocrude oil. The retention time varied from 20 to 60 min. The recovered biocrude oil can be directly combusted and used as marine fuel or upgraded by integrating downstream processes to approach petroleum oils. The biocrude oil yield was found to be 60%.
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