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The fundamentals of ignition, NO x (NO and N 2 O) emissions, and ash formation characteristics for biomass and mixtures of coal with biomass are precisely elucidated in this study. In this study, biomass, coal, and a biomass-coal mixture are burned, using an electrically heated drop tube furnace. In the combustion test, the focus is on the ignition behavior, combustion efficiency, NO x emission behavior, and formation characteristics of particulate matter, based on the results of gas compositions along the furnace axis and a collection of particulate matter by a low-pressure impactor. As a result, the addition of biomass into low-rank coal affects combustion behavior, especially for ignition enhancement. The NO and N 2 O concentrations in co-combustion are almost the same as those in coal combustion, even if the quantity of input fuel nitrogen under the cocombustion condition is half of that under the coal combustion conditions. A kinetic simulation of the NO and N 2 O behavior results is conducted, using the homogeneous reaction schemes at constant temperature. The simulation result of NO concentration agrees with the experimental result obtained. However, the N 2 O concentration calculated is less than the experimental result, because the heterogeneous schemes that are related to N 2 O are not considered in this simulation. Fine particulates with a size of <2 µm during biomass combustion are produced. Burning the biomass with coal shifts the particle size distribution from fine particles to coarse particles, which can be captured by dust collection systems.

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This study investigated the utilization of liquid smoke as a natural preservative in fish balls without reducing their nutrition and aesthetic value. The liquid smoke used in this research was obtained through pyrolysis of palm kernel shells at temperatures of 340, 360, and 380°C. The resulting liquid smoke was then purified using a two-stage distillation process at a temperature of 200°C in order to remove unwanted compounds. This grade-1 liquid smoke was then used to preserve fish balls. The parameters assessed to monitor the fish balls' preservation were total volatile bases (TVB), pH, and organoleptic test results. The results showed that the smallest TVB value of 12.66 mgN/100 g at 20 hours was obtained for fish balls preserved using liquid smoke pyrolysis at 380°C (3% concentration). The organoleptic test showed that 90% of respondents preferred the taste, aroma, and texture of the fish balls preserved using liquid smoke pyrolysis at a temperature of 340°C (2% concentration). The pH test showed that the fish balls preserved using liquid smoke possessed a pH above 6, meaning that they were in good condition.

Combustion of coal and co-combustion of their co-fuel contribute to gas emissions. Among the gas emissions are SO x , NO x , CO and CO 2 . Introduction of calcium based adsorbent is addressed to absorb SO 2 that release to the atmosphere during the combustion process. Objective of the research is at first to observe the physical characteristics of biobriquettes as a function of briquette compositions (coal to palm kernel shell ratios) and Ca/S ratios (Ca in adsorbent and S in briquette) using a natural adsorbent (shellfish waste). The second objective is to investigate desulfurization characteristics as a function of Ca/S ratios and desulfurization temperatures at coal to palm kernel shell ratio of 90:10 (wt %). Ratios of coal to palm kernel shell in this study are 90:10, 80:20, 70:30, 60:40 and 50:50; and Ca/S ratios are 1:1, 1.25:1, 1.5:1, 1.75:1 and 2:1. Binding agent used is the mixture of Jatropha curcas seeds and starch as much as 10% (wt). It was found that introducing the palm kernel shell and adsorbents in the coal briquette affect the water resistant and compressive strength. The highest water resistance and compressive strength were 5,165 second and 34 kg/cm 2 , respectively. The lowest SO 2 level found in this study was 1 ppm for all Ca/S ratios, except for 1:1.

Oil palm kernel shell is a waste product of palm oil manufacturing and contains significant amounts of several chemical compounds including cellulose, hemicelluloses, and lignin. Pyrolysis of these compounds results in good quality liquid smoke. The aim of this research was to utilize this liquid smoke to preserve mackerel. The liquid smoke in this research was obtained by pyrolyzing oil palm kernel shell at temperatures ranging from 300-380°C. The resulting liquid smoke was then distilled at 200°C, and its chemical composition was analyzed using gas chromatography-mass spectrometry. The liquid smoke was then used to preserve mackerel at a variety of concentrations, including 0.5%, 1%, 2%, and 3%. The efficacy of preserving the mackerel using liquid smoke was assessed through TVB (total volatile base) analysis and organoleptic testing. TVB testing showed that mackerel remained fresh for up to 64 hours after being treated with 2% and 3% liquid smoke at a pyrolysis temperature of 380°C, with TVB values of 26.733 mgN and 24.974 mgN, respectively. The organoleptic testing showed that at a liquid smoke concentration of 3% and a pyrolysis temperature of 380°C, mackerel can remain fresh for up to 48 hours, with acceptable color and texture, and is suitable for consumption. Meanwhile, the non-preserved (control) mackerel had already deteriorated within 24 hours in terms of color, texture, and smell.

The combination of baffled air flotation and a membrane system for the treatment of palm oil mill effluent (POME) was studied. The POME was obtained from a palm oil factory in PTPN I Tanjong Seumantoh, Aceh, Indonesia. Operation variables and conditions, such as the hydraulic retention time and air flow rates, were varied to find the optimum process. The air flotation process is able to reduce the concentration of suspended solids and fats/ oils contained in the wastewater, which increases the performance of the membrane by reducing clogging. The results showed that this method was promising for POME treatment. The optimum organic removal efficiency of the air flotation pretreatment was obtained at HRT = 5 days and at an air flow rate of 11 L/min. The effluent was subsequently passed through an anaerobic membrane system to achieve the highest removal efficiency treatment. The removal efficiency of chemical oxygen demand (COD), total suspended solids (TSS), turbidity, mixed liquor suspended solids (MLSS), mixed liquor volatile suspended solids (MLVSS), and fats/oils after passing through the membrane system were 97%, 93.9%, 99.8%, 94.5%, 96.2%, and 99.9%, respectively. The results also showed that the pH could be neutralized to 6.18, while a dissolved oxygen (DO) level of 1.60 mg/L could be achieved. A high quality of effluent was obtained, which met the standards for POME effluent.

Abstract. Presently, biomass is mostly utilized as co-fuel in coal combustion in view of energy diversification and emission reduction. However, since the coal content of bio-briquettes is high (up to 80% in this study), gas emissions such as those of SO x still occur. Therefore, the introduction of SO 2 adsorbent is common in coal briquette or bio-briquette combustion. A calcium-based material is usually used for this goal. The aim of this study was to observe the effects of desulfurization temperature and Ca/S ratio (Ca = calcium content in adsorbent; S = sulfur content in coal and biomass) on desulfurization efficiency and kinetics. The ratio of coal to biomass (palm kernel shell/PKS) was fixed at 90:10 (wt/wt) and the ratios of Ca to S were varied at 1:1, 1.25:1, 1.5:1, 1.75:1 and 2:1. The mixtures of coal, PKS and adsorbent were briquetted at a molding pressure of 6 ton/cm 2 with Jatropha curcas seeds and starch mixture as binding agents. Desulfurization was performed within a temperature range of 300 to 500°C for 720 seconds at an airflow rate of 1.2 L/min. The results showed that the highest desulfurization efficiency (90.6%) was associated with the Ca/S ratio of 2:1 and temperature of 400°C. Moreover, the highest reaction rate constant of desulfurization was 0.280 min -1 .