Effects of Parameters on Cashew Nutshell and Cassava Binder Briquettes Densification: Structural Equation Modelling

Densification improves the properties of loose biomass for use as fuels, and the process is a complex technological problem involving the interaction of variables that are interdependent on one another. The effects of process variables (pressure and dwell time) and a material variable (percentage binder, particle size, and mass) on the density of cashew nutshell and cassava binder briquettes were investigated using structural equation modelling (SEM) with the help of AMOS version 23 software. A furnace was used to carbonize cashew nut shells at temperatures of 250°C. The pulverized charcoal from the carbonization process was used to create briquettes with cassava paste as the binding medium. Different particle sizes of 0.5 mm, 1 mm, and 2 mm were used to create briquettes. Different compaction pressures (9.81 MPa, 19.6 MPa, and 29.42 MPa) were used in the absence and presence of various binder ratios (10%, 20% and 30%). SEM analysis found that factors pressure ((Path coefficient (b) = 493), binder percentage (b = 0. 406), mass (b = 0.257) and dwelling time (b = 0. 173) positively influence the density of cashew nutshell and cassava binder briquettes and conversely for particle size (b = - 0.505, C.R = - 6.010). In addition, SEM model showed that a particle size has the strongest effects on the density of the briquettes followed by compacting pressure and thirdly binder percentage. This study provides a better understanding of some of the factors that influence making of briquettes from cashew nutshell and cassava binder.

THERMAL PROPERTY OF CARBON RESIN ELECTRODES DEVELOPED FOR ELECTROCHEMICAL TREATMENT OF WATER AND WASTEWATERS

In this paper, thermal conductivity of carbon resin electrodes developed for electrochemical treatment of water and wastewater was investigated. Carbon resin electrodes were developed from used dry cells and resin using non-heat treatment processes. Thermal conductivity of the electrodes was measured and effects of particle size, compacting pressure, carbonisation temperature and percentage of the resin used on thermal conductivity of the electrodes were monitored using standard method through RE 890G and ALDA AVD 890G thermocouples at two different points (5cm apart). Effective thermal conductivity of the electrodes was modelled using Okazaki et al model. The study revealed that thermal conductivity of carbon resin electrodes ranged from 1.39 W/K. cm to 2.24 W/K. cm. Thermal conductivity of the material increased with decreased particle size (1.48 to 2.24 W/K. cm with 245 to 45mm) and decreased percentage resin (1.49 to 2.20 W/K. cm with 12 % to 1%), decreased with decreased compacting pressure (2.12 to 1.44 W/K. cm with 110 MN/ m2 to 60 MN/ m2) and carbonization temperature (2.12 to 1.39 W/K. cm with 260 oC to 30o C). Okazaki et al model agreed reasonably with the experimental data with correlation coefficient of 0.3206 and coefficient of determination 0.9917. It was concluded that particle size, compacting pressure, carbonization temperature and percentage resin play important role in thermal conductivity of carbon resin electrodes.

Dual UV-Thermal Curing of Biobased Resorcinol Epoxy Resin-Diatomite Composites with Improved Acoustic Performance and Attractive Flame Retardancy Behavior

This study has developed novel fully bio-based resorcinol epoxy resin–diatomite composites by a green two-stage process based on the living character of the cationic polymerization. This process comprises the photoinitiation and subsequently the thermal dark curing, enabling the obtaining of thick and non-transparent epoxy-diatomite composites without any solvent and amine-based hardeners. The effects of the diatomite content and the compacting pressure on microstructural, thermal, mechanical, acoustic properties, as well as the flame behavior of such composites have been thoroughly investigated. Towards the development of sound absorbing and flame-retardant construction materials, a compromise among mechanical, acoustic and flame-retardant properties was considered. Consequently, the composite obtained with 50 wt.% diatomite and 3.9 MPa compacting pressure is considered the optimal composite in the present work. Such composite exhibits the enhanced flexural modulus of 2.9 MPa, a satisfying sound absorption performance at low frequencies with Modified Sound Absorption Average (MSAA) of 0.08 (for a sample thickness of only 5 mm), and an outstanding flame retardancy behavior with the peak of heat release rate (pHRR) of 109 W/g and the total heat release of 5 kJ/g in the pyrolysis combustion flow calorimeter (PCFC) analysis.

MECHANOSYNTHESIS OF MMC Cu-C DOPED WITH Ti FOR APPLICATION OF PANTOGRAPH CONTACT STRIP (PCS)

This research was conducted to determine the effect of the addition of Titanium (Ti) and the sintering temperature variation on MMC Cu-C alloys as reinforcing elements. The process of this research uses powder metallurgical method with an alloying technique in Mechanical Alloying using a Planetary Ball Mill (PBM) machine with a speed of 600 rpm for 2 hours, the ratio of powder to ball mill is 10: 1. The compacting process is carried out using dies 11 mm in diameter and compacting pressure of 90 Kg/cm2. The sintering process is carried out 3 times, with variations in sintering of 800oC, 900oC, and 1000oC with sintering time for 1 hour in the tube furnace in the argon gas vacuum environment. The number of samples used in this study amounted to 9 samples with variations in alloy and temperature sintering, consist of MMC Cu-C alloy with dopping of Ti 0%, 0,5%, 1,5% (T=800 oC), MMC Cu-C with dopping of Ti 0%, 0,5%, 1,5% (T=900 oC), and MMC Cu-C with dopping of Ti 0%, 0,5%, 1,5% (T=1000 oC). The tests included Vickers hardness testing, metallography testing, XRD testing, and SEM-EDS testing. The addition of Ti elements and varying sintering temperature had an effect on the hardness value of MMC Cu-C material with the highest hardness value in samples with 1.5% Ti alloy (800oC) which is 87.25 HV, and and the lowest porosity value is 2.491% in sample of 1.5% Ti (1000oC).