Growing global demand and utilization of fossil fuels has elevated wealth creation, increased adverse impacts of climate change from greenhouse gases (GHGs) emissions, and endangered public health. In most developing countries, biomass wastes, which include but are not limited to agricultural residues, are produced in large quantities annually. They are either inefficiently used or disposed of indiscriminately, which threatens the environment. It is possible to convert these wastes, through densification, into high-density and energy-efficient briquettes. Densification of biomass into briquettes presents a renewable energy option as an alternative to fossil fuels. This paper reviews biomass briquetting with reference to biomass resources, feedstock pre-processing, briquetting process parameters, briquetting technology, and briquettes quality evaluation parameters. The review also includes the economic aspect of briquetting relating to costs and feasibility.

The objective of this research was to investigate the quality of hybrid briquettes developed from corncobs (CC) and oil palm trunk bark (OPTB) under a low-pressure densification technique. The materials were combined in varying ratios of CC to OPTB (100:0, 75:25, 50:50, 25:75, 0:100) and wastepaper pulp (10% by weight) was added to each mixture as a binder. The briquettes were produced using a manually operated 20-tonne hydraulic piston press at 28 °C temperature and ≤7 MPa compaction pressure. The mechanical strength of the briquettes was determined by the drop test and compression test methods, while a bomb calorimeter was used to determine the calorific values. The results showed that the physical properties of hybrid briquettes ranged from 9.24–10.00% moisture content, 0.38–0.40 g/cm3 density, and 87.60%–92.00% water resistance. Mechanical strength showed a 98.28%–99.08% shatter index and 18.47–21.75 MPa compressive strength, while calorific values ranged from 16.54–16.91 MJ/kg. The hybrid briquettes fared better than the CC briquettes. The significance of this study lies in the production of briquettes with suitable physical, mechanical and thermal properties by utilizing OPTB which have hitherto not been used, mixed with corncobs. This could bring substantial environmental and socio-economic benefits to rural communities of the developing countries.

No abstract

No abstract

Basic research on recyclable, renewable and biodegradable polymer composite materials reinforced with natural fibers is increasingly growing. In this article, we characterize agricultural waste by determining its dielectric properties for microwave absorber application. Recently, polymer composites reinforced with natural fibers are increasingly used in dielectric and aircraft applications. We used a Thermal Hake blending machine to blend oil palm empty fruit bunch with polycaprolactone grain to make a homogeneous powder. The functional groups of the resulting composites were then analyzed through Fourier transform infrared spectrometry. Thermogravimetric and differential thermogravimetric analyses were performed to determine the thermal degradation behaviors of the composites. The tensile strength, tensile modulus and elongation at break of the composites were measured in an Instron universal testing machine. A rectangular waveguide and open‐ended coaxial probe connected to a microwave network analyzer (PNA) Agilent N5230A PNA‐L was used to measure the reflection coefficient S11 and transmission coefficient S21 values and the dielectric properties of the composite materials. Results showed that the thermal stability and dielectric properties of the polymer composites decreased as the fiber content increased. The composites exhibited potential as microwave absorbers at microwave frequencies. POLYM. COMPOS., 39:E1778–E1787, 2018. © 2018 Society of Plastics Engineers

No abstract

No abstract

No abstract