In the handling and usage processes, sufficient density and durability of biomass (straw, read) briquettes should be provided. For the briquettes density standards determined the value ρ > 1.0 g cm-3. In ? the densification process usually fine grinded particles are used, what significantly increases energy consumption for stalk material cutting. Calculated energy consumption for common reed cutting to sizes less than 3 mm was > 7 kJ kg-1 but for size 20 mm it was approximately 1 kJ kg-1. The goal of the investigation was to obtain the necessary density and durability of briquettes of larger biomass particles by arranging them. The orientation of straw or reed stalks had to promote binding by the pressing operation. The long stalk linking, in the picture of coloured stalk briquettes sections, is good visible. Crushing force dependence on particle size for arranged structure briquettes is stated in laboratory experiments. The specific splitting force of arranged structure coarse chopped wheat straw and reed briquettes reaches value 35 N mm-1. It is approximately the same as industrially produced wood briquettes. Splitting force of the hemp stalk briquettes reaches 115 N·mm-1.

Level of agricultural productivity has been increased and also increased land area not utilized for food production. This area can be used for growing energy crops, including grasses. In addition, there are non-agricultural lands in Latvia suitable only for growing energy crops like Reed canary grass etc. Reed canary grass growing for energy needs could be an additional source of income for Latvian farmers, whom have harvesting technique for hay, for example dairy farming. It could be also a local heat energy source if wood in farm area is not available. Pelletizing or briquetting of dried herbaceous biomass has several advantages such as increasing energy density, improving storability and reducing handling and transport costs, but remains, of the fuel quality negatively affecting things, such as high ash and chlorine content (wheat straw 0.1 – 2.3%). Therefore, to reduce ash content and corrosion of heat transfer surfaces suggestible to make blends with others biomass where those parameters are lower. Briquettes of herbaceous biomass blends with peat are denser, durabler and take less energy for briquetting and pelleting. A new mixing method in this article is described. Experiments of biomass feeding in mixing process with belt feeder were done. The throughput of the belt feeder is increasing nearly linearly at feeder belt velocity from 0.18 to 0.89 m·s-1. The specific throughput of belt feeder was evaluated for Reed canary grass. Noticeable influence of the belt velocity on the specific throughput of belt feeder was not found.

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