Автор: Ivo Valchev
Статии
- STUDY ON POSSIBILITY FOR THE UTILIZATION OF TECHNICAL, HYDROLYSIS, LIGNIN IN COMPOSITION OF MEDIUM DENSITY FIBERBOARD
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Резюме
In the present report is presented a study on the possibility for utilization of hydrolysis lignin in the composition of Medium Density Fiberboard. For the purpose of the study in laboratory conditions were produced boards with five percentages technical lignin in their composition and different quantity of phenol-formaldehyde resin. The main physical and mechanical properties of boards were determined, and they have been compared with those of boards without technical lignin. It is compared the visual appearance of MDF with and without technical lignin. On that base was accomplished an analysis of the results with proper conclusions.
Ключови думи: Medium Density Fiberboard, technical, hydrolysis, lignin, Phenol-formaldehyde resin
- OPTIMAL PRETREATMENT CONDITIONS OF INDUSTRIAL HEMP RESIDUES TO GLUCOSE
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Резюме
Hemp (Cannabis sativa L.) is an annual herbaceous plant with excellent agrarian and economic characteristics and has been used since ancient times as a raw material for making fabrics. Industrial hemp, with its high biomass yield per hectare, has great potential for the production of biofuels and valuable products. Regulatory documents in Bulgaria allow the cultivation of cannabis plants only if they are intended for fibres, seeds for animal feed or sowing if they have a content of less than 0.2% tetrahydrocannabinol. The residue of hemp after such processing is characterised by a hardwood-like content of cellulose, hemicellulose and lignin but with a very low bulk density. The specificity of the biomass residues and the woody structure of hemp stalks requires an additional mild, wet beating prior to enzymatic hydrolysis.
The present work aims to investigate the effect of mechanical treatment of steam-exploded hemp residues on glucose yield after enzymatic hydrolysis and to determine the optimal pretreatment conditions. The classic steam and CO2 steam explosion methods are used as the first pretreatment step in this investigation. It has been found that the mechanical processing of hemp pulp leads to higher glucose yields after enzymatic hydrolysis, and this effect is reduced by increasing the steam explosion temperature.Ключови думи: hemp, mechanical treatment, enzymatic hydrolysis, glucose