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Biomass is a renewable energy and had been recognized as a promising feedstock for producing bio-fuels. In this work, pyrolysis of black wattle residues was investigated with the aim to study the product distribution and their chemical composition and predicting the optimal condition for maximized bio-oil especially aromatics content by using a two level factorial design of experiment. The pyrolysis were performed at temperature of 380 – 580 oC, Under screw feeder carried the biomass residues and weight of dolomite as catalyst of 1-5 wt% inside pyrolyzer with nitrogen gases flow rate of 20 to 80 cm3/min The detention time was controlled by reactor screw feeder at feeding rate of 120 to 240 rpm. Based on the analysis from a design-expert program to determine the appropriated condition of experiment was 515.18 oC, 120.01 rpm of feed rate and 20.00 cm3/min of nitrogen flow rate using 5.00wt% of dolomite catalyst. The elemental and physicochemistry analysis of bio-oil were determined, the chemical composition also investigated using gas chromatography-mass spectrometry and 1H NMR. The composition of bio-oil mainly oxygenated compound with high molecular weight and phenol. The results show that the biomass residual can be considered as a potential alternative fuels and relevant to valuable chemical feedstock.

In the era of climate change, life cycle analysis (LCA) has been acknowledged as a useful method for examining carbon footprints of products or services., Once captured and stored by trees and other plants, biogenic CO 2 would re-enter the atmosphere sooner or later after the use phase of the product. And many LCA studies did not calculate the temporary carbon storage in biogenic carbon. Thus, this paper proposed a hybrid LCA approach to provide a structured methodology for evaluating carbon footprint of copying paper in consideration of temporary carbon storage. The developed method was then applied to a paper mill of China. It is indicated that the hybrid LCA method could provide a comprehensive methodology for accounting carbon footprints as well as assessing effects of delaying GHG emissions. The results shows that the carbon footprint of 1000 kg copying paper was 647.89 kg CO 2 under scenario 1 and -5094 kg CO 2 under scenario 2. Concurrently, the effect of delaying the emission of the temporarily stored carbon in copying paper was 7.67%, 15.52%, or 23.58% for a certain period of time (i.e., 10, 25, or 30 years).

Instant coffee manufacture involves the aqueous extraction of soluble coffee components followed by drying to form a soluble powder. A challenge that arises from the process is the loss of volatile aroma compounds during evaporative drying. One method of retaining aroma is to first steam strip the volatiles from the coffee and add them back to a concentrated coffee solution just before the final drying stage. Understanding the impact of process conditions on the aroma content of the stripped solution offers engineers the ability to target desirable compounds and maximise their yield. This paper presents a multiscale model for aroma extraction that describes: (i) release from the matrix, (ii) diffusion through the coffee grain, (iii) transfer into water and steam, and (iv) advection through the stripping column. Results reveal how aroma physiochemistry determines the limiting kinetics at industrial extraction conditions. The interaction with the soluble matrix can also inhibit extraction, but this effect varies for the different aromas studied.

Higher alcohol (C5/C6 alcohol) blended with diesel or bio-diesel is a promising alternative clean fuel for the compression ignition engine. The most important puzzle is the technology development of biomass to higher alcohol fuels. In this paper, a novel approach of hydrothermal conversion of biomass into C5/C6 higher alcohol fuels was proposed. High yield of higher alcohol fuels was obtained from the real biomass with the C5/C6 alcohol selectivity of 77% under the mild hydrothermal conditions. The properties of the produced higher alcohol fuels are similar to that of 0# diesel. The exhaust emission of compression ignition engine decreased vigorously by blending the higher alcohol fuels with diesel at weight ratio of 20/80.

Primary treatment is a major component in modern sewage treatment systems; and chemical enhanced primary treatment (CEPT) process can further enhance its performance for energy recovery or process improvement. With significant benefits on small footprint and sludge dewaterability, CEPT process has been selected and applied as the major wastewater treatment technology in Hong Kong. CEPT sludge, similarly in composition to typical primary sludge, is rich in organic contents and therefore can serve as a proper source for bioenergy production after anaerobic digestion (AD). The heating value of CEPT sludge can be higher than that of secondary sludge, which is mainly composed of slowly degradable organics and microorganisms. If neglecting energy consumed to produce the coagulant a CEPT-AD system shall drive the wastewater treatment process from energy-negative practice to energy-neutral or even energy-positive systems. This paper demonstrates some of the most important substrate-related features to increase the bioenergy production in the CEPT-AD system. Attentions have been paid particularly on the analysis of physiochemical characteristics of the CEPT sludge and their impacts to the biological system with heterotrophic species. An innovative sulfide oxidation process was presented with experimental evidence to overcome the potential problems of sulfide induced growth inhibition of methanogens. It was expected that the new process could reduce approximately 0.744 kWh/m3 of energy consumption in comparing with conventional activated sludge process without nutrient removal.

Biogas upgrading to biomethane has received particular attention in recent years as a key strategy to produce a natural gas-substitute from biomass. Among the available upgrading technologies, amine-based absorption is an interesting option because of its low electric power consumption and very high methane recovery rates. This paper assesses the energy and economic performance of a biogas upgrading process involving chemical absorption with two different aqueous solvent formulations: 50%w MDEA and a 20%w/20%w MDEA/MEA blend. The process performance is evaluated with Aspen Plus and the optimal process conditions are determined with a multi-objective optimization approach targeting the maximum efficiency and minimum specific equipment cost. In the proposed scheme, to make the system energy-self-sufficient, an internal combustion engine burns a fraction of the raw biogas stream to co-generate both the electric power for the upgrading process and the thermal power required for solvent regeneration. Aqueous MDEA turns out to be more efficient (Pareto dominant curve) and less expensive than the MDEA/MEA blend, as a result of the lower regeneration energy (0.94 kJ/Nm3BM/h vs 1.43 kJ/Nm3BM/h) which yields to lower energy consumptions and smaller engine sizes. Even though the cost estimates are subject to a higher degree of uncertainty, the MDEA option features an expected specific total equipment cost as low as 1,550 €/(Nm3BM/h)) vs. 1,850 €/(Nm3BM/h)) for the MDEA/MEA blend.

With the popularity of ammonia fuel cell, nitrogen-containing compounds are becoming an alternative energy sources. However, most of those nitrogen compounds, especially ammonia, are dispersed in domestic wastewater and their treatment is often energy consumption. Therefore, the nitrogen retrieval from wastewater is becoming urgently needed of development. Adopting a new five-compartment electrodeionization technology, this paper demonstrates the possibility to concentrate ammonia nitrogen in synthetic wastewater. The result indicates that the optimum current is 0.18 A in artificial domestic sewage with low concentration ammonium ions among 15 mg/L. The nitrogen concentration can be enriched for about 12 times in single stage. The removal rate of nitrogen can reach over 90% with energy consumption of 19.104 g/kW·h. It explores a feasibility of recovering the ammonia nitrogen in wastewater.

In this present investigation, microwave assisted pyrolysis (MAP) was carried out for converting waste engine oil into diesel-like fuel. The addition of susceptor enhanced the heating rate and decreased the power consumption of the pyrolysis. The specific energy consumption was four times lesser when the activated carbon mixed with waste engine oil by 40%. The maximum energy was recovered from the pyrolysis at 400°C with 1.1 kW power rating which is 15.75% higher than 2.2 kW power rating at the same temperature. The physicochemical properties of pyrolysis fuel were similar to diesel. The higher calorific value was noticed for pyrolysis oil by 2.4% compared to diesel fuel. The microwave pyrolysis oil (MPO) was tested in a single cylinder diesel engine using conventional injection and common rail direct injection (CRDI). The brake thermal efficiency of MPO was increased by 4.4% in CRDI compared to mechanical injection. The NO and smoke emission was decreased by 50% and 54% respectively in CRDI compared to mechanical injection. CRDI improves the atomization and increases the injection duration period leads to decrease of the heat release rate on the premixed stage of the combustion and also attained low peak pressure during the combustion. This study reveals that CRDI improves the combustion efficiency of pyrolysis fuel used in CI engine.

Microwave co-torrefaction of sewage sludge and leucaena wood was carried out to produce biochar for the adsorption of CO2. Three mixing ratios of sewage sludge and leucaena wood were 75:25, 50:50, and 25:75. The individual and blended biomass sample were torrefied at a microwave power level of 250 W. Mass and energy yields decreased whereas carbon and fixed carbon contents increased with increasing mixing ratio of leucaena wood. The biochar with higher carbon content could be capable of adsorbing more CO2 molecules. The adsorption capacity of pure leucaena wood biochar was approximately 53 mg/g, almost four times as that of pure sewage sludge biochar. The more fraction of leucaena wood in the blend would possess an adverse effect on the composition or property of biochar, resulting in lower CO2 adsorption capacity. Four kinetic models were applied to analyze the reaction kinetics of CO2 adsorption on biochar. The CO2 adsorption on biochar was best fitted by the pseudo-second-order kinetic model. The relatively low correspondence with the intraparticle diffusion kinetic model may imply that the CO2 adsorption on biochar is more governed by adsorption reaction.

Integrating carbonization and pelletization becomes an attractive technology for energy usage of biomass resources. A challenge to find a suitable method for densification of carbonized biomass has remained for decades. Firstly, pelletization by using three kinds of organic binders, lignin, starch and polyvinyl alcohol (PVA) was compared. PVA showed a better quality on the pellet strength and hydrophobicity. Binder can be a source of tar during pyrolysis or gasification. Furthermore, a new pelletization method by using organic binders coupled with additives was suggested. The strength of PVA pellet increased by employing the biomass gasification residue (BGR) as additive. The use of the additive can helps to reduce the binder usage and provides a good disposal method of the BGR. Mechanism of the influence of the binder and the BGR additive to the pellet quality was discussed. Overall, applying PVA as a binder and BGR as additive could be an adequate solution for carbonized pellet production with high strength and low tar generation for the gasification process.

This study investigated the effects of five process parameters, namely methanol: oil molar ratio, catalyst type, catalyst concentration, reaction temperature and reaction time on the transesterification of stone fruit (Prunus armeniaca L.) oil. The physicochemical properties of stone fruit oil and the derived biodiesel were characterized. The stone fruit kernel oil biodiesel was found to satisfy both the ASTM D6751 and EN14214 standards. The optimum process parameters for transesterification of stone fruit kernel oil at an agitation speed of 600 rpm were: methanol: oil molar ratio 6:1; KOH catalyst concentration 0.5 % (of oil weight); reaction temperature 55 °C and reaction time 60 min. The biodiesel yield under these conditions was 95.8 %. These results show that the stone fruit kernel oil will serve as a low-cost feedstock for 2nd generation biodiesel production. This biodiesel can be used in diesel engines without major engine modification.

In this investigation, diesel and beauty leaf (Calophyllum inophyllum L.) biodiesel (BLB)-diesel blends (B5, B10 and B20) were used to evaluate the performance and emission characteristics of a compression ignition (CI) engine. During the experiment, the speed of the engine was varied from 1200 rpm to 2400 rpm at 200 rpm interval. The results indicated that the performance characteristics, such as BP and BSFC in biodiesel blended fuel increases with increase in engine speed at full load condition with a few exceptions in BSFC at 1400 rpm. On the other hand, BTE and BMEP in biodiesel blended fuel decreases with increase in engine speed at 100% load with few exceptions at 1400 rpm. The results also revealed that the BP, BTE and BMEP are lower, whereas, the BSFC is higher in biodiesel blended fuel in comparison to diesel. In terms of emission characteristics, the results indicated that the emission of nitrogen oxides (NOx) increases, whereas, carbon monoxide (CO), hydrocarbon (HC), and particulate matter (PM) decreases with increase in engine speed at full load condition. The results also shown that the use of biodiesel-diesel blends in CI engine led to the significant reduction in CO, HC and PM emissions in comparison to conventional diesel. On the other hand, it has been observed that the NOx emissions are increased in biodiesel-diesel blends when they are compared to diesel.

The anaerobic digestion of biodegradable fraction of municipal solid waste (MSW) is a widely used process for biogas production. However, the biodegradable fraction of MSW also contains lignocellul ...

The study is aimed to evaluate the combustion and emission characteristics of a partially premixed charge compression ignition (PCCI) engine with diesel and ethanol fuels. Ethanol was fumigated with preheated intake air at 40°C and inducted into the intake manifold of the test engine. Experimental tests were carried out with varying proportions of premixed ethanol at different engine loading conditions of 1, 2, 3, and 4 bar brake mean effective pressures (BMEP). It was explored that at lower BMEP, oxides of nitrogen (NOx) were decreased with an increment of premixed ethanol, however, at higher BMEP, the emissions increased. At all loads, smoke opacity decreased exceedingly with increasing premixed ethanol share. At part loads, hydrocarbon (HC) and carbon monoxide (CO) emissions were increased because of the high latent heat of vaporization of ethanol. Net heat release rate and in-cylinder pressure rise were found to be increased with an increasing engine load. Overall, it could be determined that the performance of the PCCI engine with ethanol fumigation is comparable with the conventional diesel fuel operation.

Recently, several research has been studied on the hydrothermal liquefaction (HTL) of food wastes to obtain bio-oils. However, most of studies do not fully discuss the physicochemical properties of liquefaction bio-oil from food wastes. In this study, the food waste was pretreated with K2CO3 at 100 °C for 1h, then raising to 300 °C for 1h in a semi-pilot reactor to produce the liquefaction bio-oil. To understand the characterization of the liquefaction bio-oil food waste and compare to liquefaction bio-oils from other feedstocks, the bio-oil was analyzed with thermogravimetric analysis (TGA) under nitrogen and air atmosphere was conducted to evaluate the thermal properties. Furthermore, GC/MS was conducted to discover the chemical composition of the bio-oil and compared the results with different kinds of liquefaction bio-oil. The obtained results revealed that the liquefaction bio-oil contains higher heating value (HHV) of 34.79 MJ/kg and the increment was about 53% compared to the original food waste source (22.74 MJ/kg). The maximum boiling point distribution of liquefaction bio-oil appears around 200 °C to 350 °C. Likewise, the ignition temperature and burnout temperature of the liquefaction bio-oil found lower when compare to other liquefaction bio-oils indicating that the bio-oil from the food is much easier to be ignited and burned. Two obviously groups, fatty acids and amides, can be easily distinguished from the GC/MS analysis of the liquefaction bio-oil components which believed mainly be converted by the carbohydrate and protein from the food waste.

Oil palm frond and empty fruit bunch (EFB), which were abundant biomass resources found in Indonesia, were hydrothermally-treated using two different types of reactor, e.g. batch and semi-flow reactor. The objective of this research was to make a comparison of product resulted from both types of treatment. Based on the experimental results, it was found that liquefaction of biomass material occurred more effectively in semi-flow reactor. Semi-flow reactor facilitated a higher recovery of several sugar compounds such as xylooligosaccharides and arabinose. On the hand, residual solids from batch treatment had higher theoretical calorific values (18.81 and 18.00 MJ/kg) than those from semi-flow (15.40 and 17.41 MJ/kg, for frond and EFB respectively).

Chicken fat and waste cooking oil commonly consumed in Indonesia, thereby causing health problem. In this study, chicken fat (CIAT) and waste cooking oil (PAIL) were used to produce methyl esters in a home-made biodiesel reactor. Transesterification is affected by alcohol type and base catalyst used. The reaction process were run for 90 minutes at 60°C and 2000 rpm stirring rate. Important properties of the biodiesel like density and kinematic viscosity has been estimated. According to the results, maximum methyl esters yield of 91% has been achieved. The fuel properties of methyl esters produced in home-made biodiesel reactor with methanol and sugarcane spirits were close to each other The home-made biodiesel properties using sodium hydroxide as catalyst were better than using calcium oxide. The production cost of CIAT and PAIL biodiesels with home-made biodiesel reactor were cheaper than government biodiesel selling price.

As the world is transitioning towards a low-carbon economy, it is becoming important to develop ways to reduce carbon dioxide (CO2) emissions. Chemical looping, a low carbon technology for the industry, is considered as a potential breakthrough technology and a viable option for efficient fuel conversion and carbon capture and storage, with the successful completion of pilot plant trials in the USA. The conversion of captured CO2 to methanol can be considered a promising method for significantly reducing CO2 emissions, while the produced methanol can be used as a convenient energy carrier for hydrogen storage. This study focuses on a process of converting microalgae, a potential fuel feedstock, into methanol by utilizing CO2 generated within the process. The specific focus lies on the conversion of the microalgae into methanol through dual-stage chemical looping and efficient process integration with maximum energy recovery. Aspen Plus® was used to simulate the facility producing 42 mt (metric tons) methanol/h using 60.1 mt/h CO2 and 8.2 mt/h H2. The process was divided into four-module operations: drying, chemical looping gasification, syngas chemical looping, and methanol synthesis. The energy efficiency of this process is around 45–51% which is comparative with the concentrated CO2-based methanol and typical biomass-based syngas to methanol processes. Because the separated CO2 obtained via chemical looping is utilized for methanol synthesis, the carbon-negative value is attained.

Entrained flow gasification of biomass has the potential to generate synthesis gas as a source of renewable chemicals, electricity, and heat. Nonetheless, formation of tar and soot is a major chall ...

In the recent decades, Jojoba biodiesel is considered as one of the most potential renewable energy sources of many countries. Thus, an investigation was conducted for the enhancement of jojoba biodiesel-diesel blends with the addition of 10% n-butanol by volume which is generally acknowledged as an oxygenated additive. Engine performance was examined at variable loads, ranging from no load (0 N.m) to 13.5 N.m at a constant speed of 2000 rpm on a compression ignition engine. The cylinder pressure and the heat release rate analysis were explored for the tested fuels to examine the behavior of the combustion process. Engine emissions of NO x , CO, and UHC were also investigated. The combustion outcomes exhibited that the maximum cylinder pressure and the peak heat release rate were slightly reduced as compared to diesel oil. There was a significant reduction in the exhaust emissions where the NO x , CO, and UHC were reduced by 80%, 80%, and 65%, respectively. It can be concluded that the addition of n-butanol with jojoba biodiesel-diesel blends has a remarkable positive effect on the engine performance and emissions.

The novel lab-scale stand-alone circular dark/photo baffled reactor (SCBR) was developed for the treatment of synthetic gelatinaceous wastewater and the enhancement of biohydrogen production (H2) using mixed microbial culture. The pilot system was operated at a constant hydraulic retention time (HRT) of 48 h with an organic loading rate of 1.3 gCOD/L/day and pH value of 6.5 ± 0.2. The results showed that the SCBR which consists of four compartments (C1, C2, C3, and C4) was efficient for the removal of chemical oxygen demand (COD). The total COD removal efficiency was recorded to be 78 ± 13% and the production rate of H2 was enhanced. The total HPR of SCBR was 14 ± 0.7 L/day. The results revealed that the production rate of volatile fatty acids (VFAs) by dark fermentation was much higher than the consumption rate by photofermentation, and VFAs production did not inhibit the H2 production or the treatment performance of SCBR.

Sludge treatment in wastewater treatment plants are one of the most difficult challenges. The purpose of this study is to determine the effect of ultrasonic waves on soluble chemical oxygen demand (SCOD), temperature and pH of the sludge during improving the sludge dewatering properties. In this research variables include ultrasound density and Time. With the increase of time, the SCOD also increased, which is due to increasing exposure of cells and microorganisms to sonification. This Enhancing Contacts with ultrasound waves leads to increasing cell wall collapse and the withdrawal of intracellular water, proteins and nutrients into the sludge. Also with the increase of ultrasound density, the rate of SCOD increase has raised. This means an increase of SCOD of the sludge and it is due to the higher import of energy and production of nano-bubbles and damage of cells and biological flocs. By increasing the ultrasound density and sonification time, the temperature was significantly increased.

The possibility to degrade spent rubber and tyre waste using microorganisms to reduce environmental threats has been considered. The present study investigated the optimization of major environmental parameters (pH, temperature, dissolved oxygen concentration, inoculum size, and tyre surface area) that would enhance the Bacillus sp. growth, an indigenous bacterial isolated from scrap tyres. The optimal conditions were determined as pH 7, 30°C, 6.7 mg/L dissolved oxygen, 10% (v/v) inoculum size, and 120 mm2 tyre surface area. Further detailed investigation is under way to pinpoint the exact organic compound(s) leached out from tyre, as growth substrate(s) for Bacillus sp.

Coffee is a global consumer product whose energy is waste. In order to reuse coffee grounds, the n-heptane was used to extract the coffee oil from spent coffee grounds. Then the coffee oil and methanol were used to prepare biodiesel through transesterification. In addition, the coffee grounds after extraction of oil was used to make solid biofuels. By experiments, the effects of different extraction methods, different proportions of n-heptane and coffee grounds, number of repeated uses of n-heptane and moisture content of raw materials on extraction rate of coffee oil and recovery of n-heptane were determined. Composition of obtained biodiesel was analysed by gas chromatography-mass spectrometer. It was found that there were many components in biodiesel, including many esters, unreacted fatty acids, and some cyclic and linear organic compounds. By thermogravimetric analysis of defatted grounds, apparent activation energies of the combustion of main volatiles, secondary volatiles and fixed carbon were determined using the Coats-Redfern method. The apparent activation energies were 96.801 kJ·mol-1, 30.973 kJ·mol-1 and 21.227 kJ·mol-1, respectively.

The design of portable biodiesel plant from waste cooking oil has been done simultaneously based on biodiesel standard of SNI 7182: 2012. Design of biodiesel production involves several processes including esterification, transesterification, decantation, vacuum evaporation, and ultra-filtration. Production of biodiesel has been simulated using several software packages. Based on the simulation conducted, the esterification process was able to convert 92.8% of FFA into FAME by using sulfuric acid as the catalyst with 10% w/w of FFA. Transesterification showed the biodiesel yield of 90% by using NaOH as the catalyst with 1% w/w of triglyceride. Evaporation on vacuum system was able to obtain biodiesel with methanol content less than 0.5% with lower energy consumption. Purification of biodiesel using ultra-filtration requires considerable energy but it was able to produce the purity rate of biodiesel up to 99.8% with relatively shorter time.

Nowadays, alternative energy from biomass has become more popular globally. Pineapple waste, one of the non-edible biomass sources from agricultural waste, can be used as an alternative source of sugar for ethanol production. However, the production of glucose from cellulose using conventional process would generally be retarded by lignin content. Therefore, the objective of this study is to investigate the effect of the hydrothermal treatment followed by the enzymatic treatment on the cellulose conversion with the presence of different lignin contents and compare the result with conventional method. Also, the physical structures of solid residues from both techniques are analyzed and compared. The results show that the hydrothermal treatment at 185°C followed by the enzymatic treatment can convert pineapple waste to a higher amount of monosaccharide, which is composed of glucose and fructose. Furthermore, the combined treatments can provide up to 23.90 % higher for the glucose yield and 226.7 % higher for the fructose yield than that of the pure enzymatic treatment. Furthermore, the reduction in the lignin content from 20.43 % to 10.88 % by weight can substantially enhance the glucose yield up to 23.90 %. Moreover, the hydrothermal treatment process can decompose the lignin structure between each cellulose strand. Without this treatment, the lignin structure will not be broken down and retard the effectiveness of enzymatic treatment.

This work aims to evaluate the carbon footprint (CF) of microalgae production in a closed pilot-scale multi-tubular photobioreactor (PBR), on a gate-to-gate approach. Primary data from real production conditions complemented with data from the literature and life cycle inventory databases was used. The carbon embedded in the PBR’s construction materials and nutrients necessary for the microalgae growth were considered. A global CF of 68.34 kg CO2-eq/kg dry biomass was obtained. A CF of 1.72 kg CO2-eq/kg dry biomass was calculated for the PBR construction stage, contributing to 3 % of the overall value. For 74 kg of dry biomass/year produced with this PBR, the CF for this stage was 66.62 kg CO2-eq/kg dry biomass, corresponding to 97 % of the total global CF. In this study, electricity production for the reactor operation is the major contributor (79 %) to the overall CF, followed by the production of nutrients used to prepare the culture medium (21 %). CO2 fixation by microalgae reduces the global value by 3 %.

The purpose of this work was the study of crude glycerol gasification, using steam as oxidant. The results were compared with those obtained for technical glycerol gasification. The producer gas composition and the gasification parameters were evaluated. Tests were performed in a fixed bed reactor and the producer gas samples were analysed by gas chromatography. The results using crude glycerol showed higher H2/CO ratio and cold gas efficiency values than the ones obtained using technical glycerol while no significant differences were observed for the remaining evaluated parameters. The results reveal that gasification is a possibility of crude glycerol valorisation.

Circular economy and bioeconomy factors has driven the economy sectors towards sustainable choices. Chemical industry, as stated by the Joint Research Centre of the European Commission, has a potential to reduce 36 % of the greenhouse gas (GHG) emissions by 2050 [1] mainly linked with introduction of emerging energy technologies. Ethylene, chlorine, ammonia and hydrogen are important chemicals for such reduction as they are the most worldwide produced chemicals (16 % of the total production in 2050 for ethylene, 11 % for chlorine and 6 % for ammonia). Meanwhile planned GHG reduction potential for these chemicals, through introduction of compression and separation technologies, is estimated as 75 % for hydrogen, 54 % for ammonia, 31 % for chlorine and 27 % for ethylene. The aim of the study is to perform an indicator analysis (raw material consumption, emissions produced and associated costs per one tonne of bioethylene) of bioethylene production pathways focusing on the following raw materials – corn, manioc, sugar cane, sugar beet, wheat and conifer.

This paper investigates the best separating material for pressure plate tests, choosing from silk cloth, filter paper and cellulose film. Measurements at 3 bar and 12 bar reveal that the influence of separating materials is negligible for autoclaved aerated concrete, while cellulose film is the best for calcium silicate and ceramic brick because of the more reliable results. Repeated tests at 3 bar further advocate cellulose film for the smallest repeatability errors. In conclusion, cellulose film is superior to silk cloth and filter paper as the separating material in pressure plate tests.

The work presented in this paper aimed to examine the effect of heating rate on the bio-crude yield of wood hydrothermal liquefaction. Three different heating methods were developed, resulting in heating rates ranging from 66 °C/min to 179 °C/min. The experiments were conducted using Norway spruce wood as feedstock at an operation temperature of 350 °C and with a total reaction time of 15 minutes. The bio-crude product was collected and separated using dichloromethane (DCM) as solvent and a centrifugal separator. The results confirm that heating rate has a clear positive effect on the bio-crude oil yield, increasing from 18.9 wt% for the lower heating rate of 66 °C/min to 35.8 wt% for the higher heating rate of 179 °C/min. It is also shown that the effect of feedstock pre-treatment via torrefaction on the bio-crude yield is negative. © 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

There is a potential to integrate biomass gasification with pulp & paper and CHP plants in order to complement the existing systems with production of chemicals, such as methane, hydrogen, and ...

To improve the stability of petroleum coke water slurry (PCWS), bubble-PCWS has been researched in this paper. The presence of bubble-particle complexes in the slurry helps to strengthen three-dimensional network structures of slurry and enhance the stability. In order to make sure the integratedly optimal levels of multi-factors for stability of bubble-PCWS and distinguish the primary and secondary influential factors on the stability, orthogonal experiments and range analysis have been done. The results showed that the operation conditions while preparing bubble-PCWS could greatly impact the slurry stability with the biggest difference between pour rates being about 80 percentage points under different operation conditions. The optimal operation condition for stability was the combination of aeration time of 30 min, solid concentration of 65 wt%, frother dosage of 0.030 wt% of the air-dried pulverized petroleum coke, aperture size of air distribution plate of 2∼5 μm and frother type of AOS, on which the bubble-PCWS possessed a perfect stability with the pour rate of more than 96%. The major factors affecting the stability of bubble-PCWS in sequence were aeration time, solid concentration and dosage of frothers. Effects of aperture size of air distribution plate and type of frothers on the stability were relatively slight within the experimental range.

Microbial fuel cell (MFC) has drawn much attention in recent years, because it can produce electricity from sewage and waste. This paper reported that the fermentation of primary and secondary sludges (i.e., mixed sludge) under the combined use of surfactant and alkaline pH condition highly improved the production of SCFAs, and using mixed sludge-derived SCFAs as the fuel could significantly enhance the performance of electricity generation of MFCs (630 mV versus 405 mV). The data indicated that the maximal SCFA production under the combined condition reached 2150 mg COD/L, which was much higher than that of the control (160 mg COD/L). The mechanism investigation showed that the combined strategy had greater sludge solubilization, higher protein hydrolysis and lower activity of methanogens. Fluorescence in situ hybridization analysis revealed that the abundance of bacteria was significantly increased, whereas that of archaea was decreased by fermentation under the combined condition. Therefore, the reuse of primary and secondary sludges under the combined use of surfactant and alkaline pH condition can be a good approach to highly improve the power generation of MFCs.

Although much research on the effect of CO2 gasification on char combustion has been reported, few studies give clear information on the proportion of carbon consumed by the gasification and oxidation respectively. In this work, a drop-tube furnace is used to study the combustion of Huangling bituminous coal char in different oxygen and carbon dioxide concentrations at different residence times. It is found that with increasing CO2 content the carbon conversion ratio decreases first and then goes up in both oxygen content of 21 and 36 vol.%. There always exists a minimal point around CO2 content of 8-15 vol.% along with increased residence time during pulverized coal char combustion. Meanwhile, a preliminary formula is proposed to calculate the overall carbon conversion ratio of char and the proportion of carbon consumed by the gasification and oxidation respectively.

In this study, characteristics of 6 different fuels which are going to be gasified in a plasma reactor are analyzed. The types of fuels are Russian coal, South Africa coal, Simak-Turkey coal, hornbeam sawdust, pine tree sawdust and polyethylene. The characteristics of these fuels are examined by measuring heating values, densities and performing the proximate and ultimate analysis on their composition. The carbon and hydrogen content have a favorable influence on heating value meanwhile, moisture, ash, oxygen, nitrogen and sulphur have an adverse effect. This fact is also confirmed by proximate and ultimate analysis. According to the results it is observed that the Russian and South Africa coals have the higher heating values because of their high carbon and hydrogen content. Meanwhile the moisture and volatile matter which are high in sawdust is the cause of reduction in heating values. Polyethylene has the highest heating value in calculation, although it could not be measured directly by a bomb calorimeter. (C) 2017 The Authors. Published by Elsevier Ltd.

Coal-derived flue gas is one of the main anthropogenic sources of mercury emission. It is always desirable to remove mercury from flue gas to eliminate associated environmental problems, which would become more beneficial if mercury is removed and recovered as a useful material. In this research, the capture and recovery of Hg0 over the TMDC MoS2-based material were carried out to study the possibility of recovery of Hg0 as a resource. The capture of Hg0 achieved above 90% in the 180 min test at 50°C at a GHSV of 4.5×104 ml/(h·g). The recovery of Hg0 was conducted during the regeneration of the adsorbent. Three regeneration temperatures, i.e., 200, 250 to 300 °C, were investigated. It was found that 200°C was the most appropriate operating temperature for the regeneration of the adsorbent, at which the maximum efficiency for the recovery of Hg0 was achieved. It can therefore be concluded that the TMDC MoS2-based material could be applied for the capture of Hg0 from flue gas as well as the recovery of Hg0 as a saleable product.

The product of degraded lignocellulose is sugar which can be utilized by microbial consortium for biogas production. However, the hydrolysis of lignocellulose to produce sugar is addressed to be the rate-limiting step due to the complexity of lignocellulose that is barricade for enzyme accessibility. The aim of this work is to study the effect of a lignocellulose degrading microbial consortium to enhance the biogas production from rice straw. Microbial consortium were isolated from natural samples, including horse manure and decomposed wood. The cellulase activities of each microbial consortium derived from horse manure and decomposed wood were characterized to be endo-β-glucanase (0.417 and 0.434 U/mg), exo-β-glucanase (0.116 and 0.184 U/mg) and β-glucosidase (1.069 and 3.184 U/mg), respectively. The batch experiments for biogas production were performed to investigate the effect of each microbial consortia. The results showed that both microbial consortium enhanced the biogas production because the biogas yield increased to 109.60 and 161.49 ml/g-VS when adding microbial consortium derived from horse manure and decomposed wood, respectively. This work is considered to be a contribution to the research on lignocellulosic biomass degradation by complex microbial community with potential for further biotechnological applications, especially the degradation of lignocellulose-based feedstocks.

The utilization of digestate from anaerobic digestion (AD) processes offers the possibility to recycle nutrient from organic wastematerials back to the food chain. However, digestates are character ...

Biogas has been considered as an alternative renewable energy, and CO2 removal from raw biogas (i.e. biogas upgrading) is needed for producing biomethane used as vehicle fuels or injected into the natural gas grid. Biogas upgrading using physical absorbents is a simple and efficient technology with low energy requirements for regeneration. In this work, the conceptual process for biogas upgrading using 4 kinds of physical solvents, i.e. water, dimethyl ether of polyethylene glycol (DEPG), propylene carbonate (PC) and aqueous choline chloride (ChCl) /urea (AQDES) was developed and simulated with Aspen Plus. The energy utilization, the amount of recirculated solvent and the diameters of absorber and desorber were analyzed based on equilibrium approach. After that, the rate-based simulation was established to evaluate the specific cost of the process using different solvents. Based on equilibrium approach the comparison between the solvents in respect to the energy utilization for biogas upgrading using different solvents shows the following order: DEPG > water > AQDES > PC, whereas the amount of recirculated solvent and the diameters of absorber and desorber follow another order: water > DEPG > AQDES > PC. The rate-based results show that the process using PC has the lowest total specific cost, followed by AQDES, water and DEPG.

This work including, the possibility of reducing the loss of light hydrocarbons by introducing micro-quantities of an additive having surface-active properties as new method. There have been successful attempt to use free fatty acid (FFA) on the form of artificial salt to reduce the loss of light hydrocarbons. The optimal concentration of this salt was determined by estimating the lowest pressure saturated with steam its (8 mg/kg). It was found that the evaporation rate reduced to 47% in the oil tanks. It has been observed that the effect of adding this compound to the oil tank is to be slightly, it was also found that the presence of artificial salt compound at the bottom of the tank is 10%. In this case, it appeared to be advantageous to use this method for reduce the loss of light hydrocarbons, which should prevent the loss of light hydrocarbons.

Nowadays, alternative fuels to fossil-based ones are emerging, one of them consisting in the use of oxygenated fuels, i.e. short-chain alcohols. Their main advantage is that alcohols may be produced by renewable processes. In the present work, diesel engine exhaust and acoustic emissions using different short-chain alcohols (ethanol and 1-propanol)/diesel fuel blends have been analyzed. For this purpose, nine engine steady-state operating conditions at moderate loads, covering the most used quarter of the engine map, have been selected. The effect of the increase of alcohol in the blend provided a reduction of nitrogen oxides (NOx) and soot emissions, while soluble organic fraction (SOF), total hydrocarbons (THC) and carbon monoxide (CO) emissions increased. Moreover, a rise of noise was observed with the increase of the amount of alcohol in the blend. It may be concluded, from this field trial, that at similar concentration of alcohol blended with diesel fuel (10% v/v), propanol showed better behavior in terms of global exhaust and noise emissions than ethanol.

This study aims to examine the nonsterilized fermentation conditions for coproduction of pectinases and lipase enzymes using several fruit wastes as an energy source. Thermophilic fungal strain, Pe ...

Lignocellulosic biomass is utilized as raw materials for biofuel and electricity production in different ways. The major bottleneck of biofuel production from lignocellulosic biomass is the saccharification to produce small molecules of sugars that subsequently converted to value added compounds. Pretreatment is performed before saccharification to enhance conversion rate. In this study, acetic acid was selected to pretreat oil palm shell to enhance the production of reducing sugars in enzymatic saccharification reaction. To obtain the maximum sugars, Response Surface Methodology (RSM) with Box-Behnken design was applied in the pretreatment. Three variable factors, including reaction time, reaction temperature and acetic acid concentration were varied with three levels. The generated model has high correlation coefficient (R2) at 0.9725 indicating the high confident level. Based on the model, the maximum reducing sugars at 40.408 mg/g-biomass could be obtained at optimum condition (107.30 oC reaction temperature, 30 min reaction time and 8.24% acid concentration). The results of this study suggested the benefit of using acetic acid for improvement of saccharification of lignocellulosic biomass to biofuel.

Biodiesel is alternative bio-fuel to substitute for diesel fuel which produces harmful emission causing environmental problems. The common feedstock for biodiesel production was edible oil which effected to high production cost. In order to conquer this problem, waste material was appeared to be an attractive choice. The oil from waste coffee grounds (WCGs) has the potential to use as raw material. However, high free fatty acid (FFA) concentration (>1%) in extracted oil from WCGs requires pretreatment prior to transesterification. Therefore, FFA was treated by using sulfuric as acid catalytic. In this study, the optimization of esterification of extracted oil from WCGs was investigated by using response surface methodology (RSM). The effect of operation parameters to pre-treatment of FFA was conducted using laboratory scale. The predicted optimum condition results indicated that %FFA of the waste coffee grounds oil (WCGO) was decreased 94.97% when the condition was carry out with methanol 10 mole per mole of FFA in the presence of 15% w/w of %FFA-to-catalyst ratios for 115 min reaction time at 65°C.

In this work, the condensable gases of the bio-oil produced from its fast pyrolysis at 500 oC for 30 s has been analyzed by Py-GC/MS. Relatively high yields of acetic acid, phenolics and levoglucosan have been found. Levoglucosan can be used as a source for synthesizing bio-fuels and both, phenolics and levoglucosan in the production of chemicals. However, further research is necessary in order to find adequate ways of using the great potential of this type of lignocellulosic biomass for developing a bio-based economy less dependent on fossil fuels and more respectful with the environment.

Biogas is formed naturally when palm oil mill effluent (POME) decomposes in the absence of oxygen. Unharnessed, this gas is an unwanted, potentially hazardous contributor to global climate change. Biogas is typically composed of 50–75% methane (CH 4 ), 25–45% carbon dioxide (CO 2 ) and trace amounts of other gases. To overcome POME hazardous problems and retain the methane gas, CH 4 , this research introduces newly designed of an integrated technology of ultrasonic and membrane for a palm oil mill effluent treatment. To fit kinetic study, six steady states were investigated and the results have shown that the mixed liquor volatile suspended solids (MLVSS) ranges from 12,600 to 19,500 mg/l while the mixed liquor suspended solids (MLSS) ranges from 14,700 to 23,800 mg/l. Three kinetic models Monod, Contois and Chen & Hashimoto were used to evaluate the integrated system at organic loading rates ranging from 1 to 15 kg COD/m 3 .d. The percentage efficiency of COD removal was from 91.6% to 98.5% and hydraulic retention time, HRT from 400 to 9 days. The influent COD concentrations of the POME ranged from 65,600 mg/l to 86,400 mg/l. The integrated technology of IUMAS is a more attractive solution compared to the case when the palm oil mill effluent either ultrasonic or membrane technology individually.

The sulfate-rich wastewater from rubber smoked sheet industry could generate hydrogen sulfide (H2S) under anaerobic condition, which created bad smell to the community and might cause toxicity and damage to the environment. The H2S can be removed from the biogas by sulfur-oxidizing bacteria (SOB) with the ability to converted H2S to sulfate. Sulfate-reducing bacteria (SRB) could remove sulfate in wastewater before anaerobic treatment for biogas production. The microbial sludge from wastewater and anaerobic digestion system was collected and test for sulfate and H2S removal efficiency. Anaerobic microbial sludge has a high ability to produced methane from gelatin with a specific methane production rate of 92.4 ml CH4 gVSS-1 day-1. Anaerobic microbial sludge has lower methane production when gelatin and sulfate used as a substrate with a specific methane production rate of 81.4 ml CH4 gVSS-1 day-1. The biomethane potential, hydrogen sulfide removal and sulfate removal in anaerobic digestion system by addition of enriched cultures of SOB and SRB were investigated. The methane yield of SRB consortium was 60.1 ml CH4/gCOD with 20% sulfate reduction from wastewater and no sulfide reduction. The methane yield of SOB consortium was 41.9 ml CH4/gCOD with no sulfate and sulfide reduction from wastewater. The addition of SRB consortium could increase methane production by reducing sulfate concentration in wastewater consequently to a reduced concentration of H2S in biogas.

In this study, the potential of the important economic crops of Southern Thailand for pellet making was utilized. The biomass pellets were prepared from oil palm leaves (PL) and frond (PF), para-rubber leaves litter (PAL) and branch (PB) and their blend (mixing of 50 wt.% of two materials). The raw materials which collected from local plantation were cleaned, dried and milled into small particles less than 1 mm and then continued with pellet forming by a single unit press in a laboratory under the temperature and pressure of 130°C and 350 psi. Some characteristics were analyzed to evaluate quality of pellet, i.e. moisture content, density, ash content, calorific value. Moreover, the combustion behavior was investigated by means of thermogravimetry analysis. The lowest ash content of 2.27% and 2.82% were received from PB in case of pure pellet and PB+PAL in case of mixed pellets, respectively. The calorific values of pure pellets were 16.05, 17.68, 18.71 and 19.64 MJ/kg for PF, PL, PB and PAL, respectively. The combustion characteristics were exhibited in the ignition and burnout temperature, which drawn from TG curved. The burnout temperature was improved with higher in all cases of mixed biomass pellet. The characteristics of mixed biomass pellets differed from pure biomass pellets which contribute to the further improve its quality.

Anaerobic digestion is a biological process that can be used for food waste and leachate treatment. A semi- continuous anaerobic digestion experiment was carried out treating a synthetic feedstock made of 50% synthetic food waste and 50% leachate. The total solids concentration inside the reaction was maintain constant and different TS were investigated varying from 5 to 7% TS. The aim of this study was to investigate the effect pH and Oxidation Reduction Potential (ORP) on the biogas production at the different organic loading rate tested. These operational parameters were used to predict and control a mesophilic screw digester. The results of this study indicated that the optimum of ORP and pH during the acidogenesis phase were -284 ± 32.71 mV and 5.76 ± 0.24, respectively. The optimum of ORP and pH during the methanogenesis phase were -335.63 ± 28.97 mV and 7.49 ± 0.24, respectively. The highest biogas and CH4 content were obtained for the OLR equal to 5%TS condition. The value of biogas and CH4 content were0.29 L biogas/g COD utilized and 68% of methane content, respectively.