Evaluation of different binding materials in forming biomass briquettes with saw dust

Abstract- Biomass briquettes are often used as an energy source for cooking purpose and in some industries like bricks and bakery. The briquettes are produced by densification of waste biomass using various processes. In this study manual densification of saw dust was tested with three different binding agents; dry cow dung, wheat flour, and paper pulp. The samples with cow dung as binding agent failed with mould detaching and minimum required binder percentage for other two binders for successful forming were found to be 30%. Density of briquettes with 30 % binder of wheat flour and paper pulp was found to be 373.7 kg/m3 and 289.8 kg/m3 respectively. Natural drying time was evaluated at 86~89 % relative humidity and 25~30oC ambient temperature. The time for achieving 15 % moisture content (wet basis) was 55 hours. Compressive strength of the briquettes was tested for binder percentages of 30%, 40 % and 50 % (dry basis) of wheat flour and paper pulp binders. Results indicated that compressive strength increased with the increase of binder percentage. The briquettes with paper binder exhibited comparatively high compressive strength compared to wheat flour binder. Calorific values of briquettes formed having 30% paper binder and 30 % wheat flour binder were found as 18.14MJ/kg and 20.04MJkg respectively, whereas the value of pure saw dust was 18.8 MJ/kg. The briquettes formed with paper pulp gave the minimum energy cost, the value bein