Hemp Biomass and Biodisel (Published)
Hemp (Cannabis sativa L.) is grown for various purposes of using the fibre, cha and seeds. It is one of the oldest non-food crops in the world. In Europe, hemp, together with flax, were the most important fibre plants from the 16th to 18th centuries. Later, hemp cultivation diminished but, recently, in many countries, such as Germany, France, the Netherlands, Great Britain, Spain and Italy, interest in this plant is growing, particularly in properties other than fibre. Hemp has been rediscovered as an interesting industrial plant with great uses that can be grown under a wide range of agro-ecological conditions, and is more efficient compared to many other plants. It is important that hemp biomass is also processed into a number of hemp-derived products, including oil, essential oils or CBD (cannabidiol) substances, building material and biofuel, thereby producing many components that have been of great interest to people lately. Properties of this plant have made it an excellent raw material for the development of multi-output systems through gradual distribution of biomass into several useful components. In terms of growing hemp, due to the abundant vegetative part of the plants, large biomass increases (up to 50 cm/month) show great opportunities to use solar energy and CO2 during photosynthesis (up to 2.5 Mgha-1), which strengthens its position in the group of energy plants contributing to renewable energy sources. In terms of its energy use, it is important that the green crop yield from hemp is, on average,14.5 tha-1 (calculated on the dry matter), of which 70–75% are hemp shives (by-products of hemp processing), which are usually left in the field, constituting organic fertilizer. It is possible to obtain approximately 10.5 tha-1 of raw material, which can be potentially used for energy purposes. At the same time, hemp biomass shows a significant variation in fuel properties (calorific value, heat of combustion, ash content, ash softening temperature) depending on the season in which the harvest takes place. Research conducted by).Hemp has high dry matter content and good energy concentration per hectare. Moreover, hemp has a good ratio of energy efficiency to input and is, therefore, an above-average energy crop. With respect to other energy crops, the advantages also occur outside the energy balance, e.g., they relate to the low level of required pesticides and good competition in relation to weeds. Biodiesel has many environmentally beneficial properties. It is one of the largest sources of energy reserves in the world as it approximately supplies 14% of world’s energy consumption. Many initiatives are being given for promoting the biofuels. Among the biofuels, biodiesel gets more momentum as it has properties similar to the properties of diesel fuel. Biodiesels are biodegradable, renewable and more environment friendly than petroleum based fuels. One promising source for biodiesel production is the fiber crop Cannabis sativa. It is an annual herb and its cultivation has a low cost and a low environmental impact. Cannabis sativa plant grown in temperate zones as an annual cultivation from seed and can reach a height of up to 5 meters (16 feet). Seeds have high oil content, ranging from 26% to 42%. In addition, cannabis sativa has advantage as a fuel source. It has a high biomass content which can be fermented to create low carbon fuels, such as bioethanol or biobutanol.