The production of solid materials from vegetable residues by carbonization for different usage areas

Carbonization process are applied to produce solid, liquid and gas products with high carbon content by heating the biomass in the absence of air. Biochar, solid product of carbonization process, is used in many applications such as biofuel, metal reductant, soil amender and actived carbon. When used as a soil amender, most important characteristics of biochar are increasing soil pH, improving soil CEC and water holding capacity, and providing refugia for microorganisms. High demand for food as a result of increase in world population and decrease in available fertile cultivation areas provided development of soilless culture tecniques as well as those for soil culture. As well as its soil ameliorant effects, biochar can also be used as substrate instead of soil. Hydroponic system, one of the soilless culture methods, is the technique for providing optimum plant growth in nutrient solution. There are various inorganic and organic substrates for supporting plant root in hydroponic systems. By its physical and chemical properties, biochar has a high potential to be used in hydroponic system, in the class of organic substrates. In this study, by using split type pipe reactor under different experimental conditions, biochars were produced from olive seed and tomato stalk and the parameters such as carbonization temperature, nitrogen gas flow and heating rate that effect on biochar yield were investigated. Maximum solid product (biochar) yield under 773 K carbonization temperature, 5K/min heating rate and 500 ml/min nitrogen gas flow conditions for olive seed and tomato stalk are 32.58 % and 37.53 %, respectively. Characterization process of carbonization solid products are performed by using FTIR, TGA, SEM ve BET devices. To investigate the effect of carbonization solid products by applying into soil and using as solid growing medium in soilless culture, tomato seedlings have grown and comparison of carbonization products and their mixtures at different ratios with other substrates used in soilless culture such as perlite, coconut coir presented. Among all solid growing mediums, the highest tomato seedling is obtained in the olive seed biochar medium. All of the results support olive seed biochar to be used as solid growing medium for soilless techniques.