Research
Economic Feasibility of Briquetted Fuel
Commercialization of briquetting technology, it is essential to know whether the technology was economically viable or not. Therefore an attempt was made for estimation of economics of the briquettes prepared from carbonized cashew nut shell and other selected biomass. The briquettes were prepared on screw press extruder briquetting machine for different combinations of major biomass. The prepared briquettes after sun drying were subjected to various tests for assessing the quality of fuel. The suitability of briquetted fuel as domestic fuel was studied with standard water boiling test. Cashew shell briquettes burnt with good flame in cook stove and observed 15.5 per cent thermal efficiency. Better results in cashew shell briquettes related to calorific value, shattering indices test, tumbling test, degree of densification, energy density ratio, resistance to water penetration and water boiling test as compared to grass and rice husk briquettes were observed. Calorific value was found more in cashew shell briquetted fuel as 5154.58 kcal/kg. Net Present Value of cashew shell, grass and rice husk briquettes were 1935370.8, 2256434.38 and 631948.8 respectively. Pay back period for cashew shell, grass, rice husk briquettes were 8.1, 7.56 and 29.35 months respectively. Benefit Cost Ratio for cashew shell, grass, and rice husk briquettes were 2.8, 2.93 and 1.51 respectively.
EXPERIMENTAL EVALUATION OF SOLAR DRYER FOR KOKAM FRUIT
Rotary solar dryer developed and evaluated for Kokam drying. Kokam fruits were selected as drying material. Time required reducing the moisture content upto 10 % as a safe storage for solar dryer was observed for ripen and unripe kokam fruits. Evaluation parameters were collection efficiency, system drying efficiency, pick-up efficiency, moisture ratio and drying rate. Maximum temperature inside the foldable solar dryer was 570C whereas maximum ambient temperature observed was 35.30C and solar irradiation was 600 W/m2.Humidity varies from 32.2% to 22.3% inside the solar dryer whereas outside humidity varies from 43.02% to 29.35%. Overall collection efficiency was found as 70.97 %. Maximum drying efficiency for salted ripen kokum was 9.88 per cent and unsalted salted ripen kokum was 7.66 percent.
