Innovative Biochar-Based Composite Fibres from Recycled Material

Carbon materials are becoming crucial in several industrial sectors. The drawbacks of these materials include their high cost and oil-based essence. In recent years, recycled materials have become possible alternative sources of carbon with several advantages. Firstly, the production of this alternative source of carbon may help to reduce biomass disposal, and secondly, it contributes to CO2 sequestration. The use of carbon derived from recycled materials by a pyrolysis treatment is called biochar. Here, we present composite materials based on different biochar filler contents dispersed in several thermoplastic polymer matrixes. Electrical conductivity and tensile break strength were investigated together with the material characterisation by DTA/TGA, XRD, and scanning electron microscopy (SEM) imaging. Materials with good flexibility and electrical conductivity were obtained. The local ordering in composites resembles both biochar and polymer ordering. The similarity between biochar and carbon nanotubes’ (CNTs) XRD patterns may be observed. As biochar is highly cost-effective, the proposed composites could become a valid substitute for CNT composites in various applications.

Variation of Macronutrients in the Stover of Maize Varieties Grown in Western Kenya

Large scale agricultural activities in Kenya include maize growing. Farmers plant different varieties of the species Zea mays. Though seed companies provide seeds based on altitudes, maturing periods and yield predictability, it remains the prerogative of the farmer to make choice. Yields from small scale farms are declining at every harvest despite Governments efforts to provide fertilizers at subsidized prices. Though soil acidity levels could be an accounting factor, the maize varieties planted differ in the amounts of macronutrients they remove from soils and yet next seasons’ fertilizer application is uniform. The study sought to determine and compare levels nitrogen, phosphorous, potassium and calcium in stover of maize varieties grown in Lugari, western Kenya. This was with view to inform on macronutrient removal by the different maize varieties. It too was to enable farmers speculate on the possible methods of biomass disposal for some of the methods like burning the stover either as fuel or clearance ignores the need to have an approach that would enable recycling and certainly depletes the soil. Stratified random sampling of both cobs and stalks from farmers in Lugari, western Kenya was done. The samples were dried, milled before wet digestion. The digests were subjected to laboratory analysis using standard AOAC procedures viz avis nitrogen (Kjeldahl’s method), phosphorous (Ascorbic acid method) and both potassium and calcium (Flame photometry) to establish levels of macronutrients. It was established that maize stalks of any given variety had higher levels macronutrients compared to cobs of the same variety. It was too observed that for both stalks and cobs there was significant differences (p< 0.05) between varieties in all macronutrients except phosphorous. The stover from varieties DK, H6213, H614 and pioneer had significantly higher levels than varieties H500, H505, H513 and oduma. It is hoped that the results of this study not only informs of levels of macronutrients retained by the maize stover but also provides basis for sensitization on method of biomass disposal to minimize soil degradation.

Co-Firing Feedlot and Litter Biomass: Coal Blends in a Laboratory Scale Boiler Burner

The co-firing of animal biomass fuels with coal has the potential to solve both biomass disposal problems, and reduce net CO2 emissions. The high flame temperatures produced by coal will allow the low heating value, high ash biomass to be completely burnt. Unfortunately, the animal biomass fuels are high in nitrogen and sulfur, which could lead to greater air pollution levels in the form of NO and SO2. To determine the effect of switching to 90:10 Coal:biomass blend on combustion efficiency and emissions, the blends were fired in a 30 kW (100,000 BTU/hr) laboratory scale boiler burner. The results are presented along with the their relation to the fuel properties.