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In this paper, the hydrodynamic flow inside an internally circulating fluidized bed (ICFBG) was characterized using experimental and three-dimensional computational fluid dynamics (CFD) models. Eulerian-Eulerian model (EEM) incorporating the kinetic theory of granular flow was implemented in order to simulate the gas–solid flow. A full-scale plexiglass cold flow experimental model was built to verify simulation results prior to the fabrication of the gasifier. Six parameters were manipulated to achieve the optimum design geometry: fluidization flow rate of the draft tube (Qdt), aeration flow rate of the annulus (Qan), initial bed static height (Hbs), draft tube height (Hdt), draft tube diameter (Ddt), and orifice diameter (Dor). The investigated parameters showed strong effect on the particle flow characteristics in terms of the pressure difference (ΔP) and solid circulation rate (Gs). The predicted results by simulation for the optimum case were in close agreement with experimental measurements with about 5% deviation. The results show that the ICFBG operated stably with the maximum Gs value of 86.6 kg/h at Qdt of 350 LPM, Qan of 150 LPM, Hbs of 280 mm, Hdt of 320 mm, Ddt of 100 mm, and Dor of 20 mm.

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This research aimed to enhance the performance of biomass combustion-based stove. Thermal performances were assessed in terms of power output (Pout), specific fuel consumption (SFC), thermal efficiency (ηth), and burning rate (BR). These performances were expected to meet the minimum standards established by the Indonesian biomass stove alliance regarding the use of a healthy and energy-saving of biomass stove in Indonesia. The stove tested was an improved stove with an advantage on the air distributor by adding a component to administrate air combustion needed placed on the centre of the combustion zones. This is a very effective way to distribute air for combustion required where the air could reach all the fuel and the combustion product that occupy entire the combustion zones to ensure high combustion zone temperature. Coconut shell was used as feedstock. This biomass was found abundant in Indonesia and was widely used as heat source by burning it directly. The coconut shell was sized uniformly about 5 cm x 5 cm, dried by utilizing sun energy. To estimate the stove performances, several combustion tests was carried out where the air flow rate into the stove (Qa) and the amount of biomass fuel (mb) referred as the air–fuel ratio (A/F) were considered. The Water Boiling Test (WBT) was performed to assess this improved stove. Parameter required such as initial mass of coconut shell, the mass of residual ash, the initial mass of water, mass of water after boiling, and the time required to boil as well as combustion flame temperature were recorded and used to determine the performance of the improved stove studied.

Biomass has been known as a source of energy with a thermochemical process that produces heat and can be converted further into electricity. However, thermal energy losses are a huge problem during combustion. To overcome this problem, a system based on organic Rankine cycle (ORCs) was developed to recover and utilize them to generate electricity. The proposed ORCs include an evaporator, a turbine, a condenser, and a pump coupled with a biomass carbonizing system to create a promising technology for small-scale electricity generation. In this work, a thermodynamic modelling equation based on energy and exergy balances was briefly expressed for each subcomponent of the system. A case study with R134a as the working fluid is being investigated to validate the system’s performance. In addition to the effects of R134a on temperature at the turbine exit, the suitable operating pressures has been specially adopted from several valid journals that focused on the effects of a wide range of possible operating pressure on the working fluid characteristics, which have a significant effect on the system performance. Finally, the theoretical analysis shows that the turbine work is profitable at an inlet pressure of 5 bar and an outlet pressure of 2 bar. This system is recommended to be integrated into the thermochemical biomass process. Recommendations have been made for the future development of small-scale biomass-fuelled power generation systems. This study shows that the thermal losses of the biomass thermochemical processes can be theoretically recovered in the form of electricity by using ORC efficiently.

The main problem related to thermal energy is that the thermal energy must be used directly and immediately as generated. For example, the thermal energy of solid waste combustion can be directly utilized for power generation. However, studied of thermal energy storage technology is still placed on the second opinion on waste to heat energy. The heat can be stored using a simple or mobilized system which can store thermal energy and can be brought to somewhere it is needed, for example on domestic heating or drying usage. This article studied and evaluated a micro thermal energy storage system from household waste combustion into a warm water that is great for washing clothes, dishes, shower, and other purposes of household needs. System considered was a simple manner and water is used as the heat energy storage medium. In this study, the equations for initial parameter calculation were presented theoretically based on thermodynamic principle. This paper is hopefully beneficial to the researchers and engineers for preliminary design and development of a heat storage systems technology.

Plastic distillation with pyrolysis method is one of the ways that can be used to convert plastic waste into useful chemicals and fuel oil. The purpose of this research is to design a simple plastic waste distillation design model, knowing the oil yield that can be obtained and the calorific value of oil from plastic distillation. The distillation device consists of a 12-liter volume reactor and a condenser with 0.5-inch copper pipe formed spiral with a total length of 1.5 meters and liquid cooled. The test was carried out with 2 kg Polyethylene Terephthalate type plastic material per process with 3 variations of temperature of 300 ° C, 350 ° C, 400 ° C and using LPG as fuel. The test results, the highest amount of oil produced is 49 gr at a pyrolysis temperature of 400 ° C with the heating value obtained from the distillation oil is 1537 J / gr.

The quality of liquid smoke and charcoal product yield can be improved by conducting pyrolysis process through indirect heating process. However, a great huge of energy is required to reach the exact operating temperature. In this experiment, slow pyrolysis of coconut shell is performed for liquid smoke and charcoal production using indirect method where the feedstock is just heated in a tube by using LPG as the heat source. The effect of feedstock size and the operating temperature on the liquid smoke and charcoal yields are investigated by varying the coconut shell sizes in the ranges of 1 to 7 cm2, while the operating temperature is expected as low as possible to reduce the energy required. The optimum process conditions for maximizing the two products yields and quality were also identified to meet the user requirement. The various characteristics of liquid smoke obtained under the optimum conditions for maximum yield are identified based on standard test methods. Data from a simple way of charcoal and liquid smoke production during preliminary research of this study indicated that the coconut shell sizes, and the operating temperatures are the crucial parameter during process.