Search

Wastes from paper industry are mostly combustible. It is possible to recycle them with energy recovery. These wastes have a high moisture content (up to 60%) and thus a small calorific value. An alternative to waste incineration is the production of solid recovered fuel. The benefits are: easy adjustment of the physical and chemical properties of the fuel (via the change of proportions of ingredients), low moisture and high calorific value. The study involved the following types of cellulose wastes: - Belmer - the rejects from recovered paper, Krofta - deinking sludge, sludge - wastewater treatment sludge, bark - the rejects from virgin pulps. The results of investigations of waste produced in one of the biggest Polish paper mill - are shown. Following aspects were investigated: energy properties, content of carbon, hydrogen, sulfur, chlorine and nitrogen, chemical composition of ash. Authors proposed two formulas of the biomass fuel. The properties of the fuel such as the content of carbon, hydrogen, sulfur, chlorine or nitrogen, the chemical composition of the ash were investigated. Due to the fact that the combustion of the biomass fuel is preferred in view of law regulations (zero CO2 emission, green certificates) the content of biodegradable fraction was examined. It has been shown that the fuel is a biomass one. Fuel from waste can be a substitute for approx. 25% of primary fuel (coal) used by the paper mill.

Experiment shows that wheat straw ash has rich biomass activity. Many scholars have shown that the strength, durability, freezing and thawing resistance of concrete have changed greatly after the wheat straw ash material is mixed into concrete as an active mixed material. This paper reviews and looks forward to the future development direction.

Oil palm empty fruit bunch (EFB), mesocarp fiber (MF), palm kernel shell (PKS), oil palm trunk (OPT) and oil palm frond (OPF) are the common solid lignocellulosic biomass generated from oil palm industries. A palm oil plantation was estimated to generate 36.5 ton of dry biomass in each hectare every year which suggesting the abundancy of these wastes. Feedstock feasibility and common properties as a carbon-rich material, have initiated an interest to utilize these biomass for biochar production. This paper provides a review on the developed thermal conversion technologies to synthesize biochar from oil palm biomass and includes the respective product quality such as carbon contents, yield and other physicochemical properties. The sustainability of oil palm biomass as the feedstock for biochar production in Malaysia were also described by providing the overview on biomass availability, biomass industry value chain and respective characteristics. Determining appropriate type of biomass and applying effective type of thermal conversion technologies produce biochar with good physicochemical qualities. This review observed that lignin in biomass contributes significantly to biochar production and slow pyrolysis technique is a promising technology to yield a good quality of biochar.

The paper makes a comparison between four types of briquettes: first was wheat and rapeseed briquettes, second was wheat briquettes (batch 2018), third was wheat briquettes (batch 2017), and fourth was lucernes briquettes, from the point of view of the physical and energetic characteristics, in order to choose the best ones and their corresponding market. The main properties studied are the density and moisture of the briquettes, physical properties, and also calorific power and ash content as energetic properties. Research results show that wheat and rape briquettes have had high calorific value but low density, compared to other types of briquettes. A general conclusion rise from whole paper, respectively the vegetable biomass is a renewable material and briquettes from it remains the best option of combustible materials.

In this paper authors present research results which are the optimum parameters of the torrefaction process using straw from oats and maize. The most important parameters for the torrefaction process are temperature and residence time. Both parameters are essential to designing and construction of industrial biomass torrefaction installations. Energy crops and waste coming from agricultural production have the most promising perspective from all kind of renewable energy sources in Poland. Currently, intensive studies on the process of biomass torrefaction are being carried out. In this experimental investigation, authors examined the torrefaction process of two types of agriculture biomass, such as: oats, maize. The main overarching objective of the experimental studies described below is the development of various biochar as an additive to agricultural fertilizers resulting from the conversion of biomass from agriculture residues – straw from oats and maize. The last of enumerated biomasses is treated through different conversion processes such as: drying, torrefaction to homogenize their physical and chemical properties. Among many of its areas, it is extremely important to optimize the production of biomass energy plants and its refinement (in the torrefaction process), which will improve the balance and profitability of energy production from RES, and reduce the logistics and storage costs of this fuel and improve the efficiency of biomass combustion process. When implementing new technologies indicated in this work and optimizing the harvesting of plant biomass, the negative impact on the environment caused by stored municipal waste can be reduced. This biomass torrefaction process temperature and residence time were necessary for the design and construction of semi-pilot scale biomass torrefaction installations with dryer and torrefaction reactor to perform a continuous biomass torrefaction process using superheated steam

This paper presents preliminary research of lignocellulosic biomass torrefaction by using microwave heating. The experimental setup was developed using a microwave oven with 2.45 GHz frequency. The torrefaction effect was studied by varying the microwave power level (160-480 W) and reaction time (5-30 min). The two Polish biomass feedstock, agricultural residue (wheat straw) and energy crop (Miscanthus giganteus) were used in this study. Fuel properties like H/C and O/C ratio were assessed from elemental composition. Mass yield and energy yield of the torrefied fuels were also determined. It was found that higher microwave power levels contributed to higher heating rate and reaction temperature, and thus produced the torrefied biomass with higher heating value and lower H/C and O/C ratios.

The co-pyrolysis performance of coal and biomass was studied and the influences of corn straw on Shengli lignite pyrolysis were discussed in this paper. The results show that corn straw has much higher activity and lower char yield than Shengli lignite during pyrolysis process. Release of moisture in blends were more occur than individual pyrolysis of Shengli lignite and corn straw. Weight loss of experimental value was lower than that of calculated value in blends. The pyrolysis process of Shengli lignite was remarkably affected by adding corn straw. There exists positive synergistic effect between Shengli lignite and corn straw in co-pyrolysis process. Corn straw could reduce the pyrolysis activation energy of SL dramatically above 350 oC.

Biogas fermentation rate is largely affected by environment temperature, causing a much more difficult production of biogas digesters in cold winter, for most regions in China. Combining the abundant solar energy resources and biomass dry anaerobic fermentation together, solar thermal energy can guarantee the production of biogas in winter. With this method, the prediction of the appropriate fermentation temperature is required. In this study, the effect of temperature on biogas fermentation was studied. To predict the fermentation temperature, a heat transfer model of biogas fermentation based on a project in city Xuzhou, which assisted with a simple solar greenhouse, was established according to the heat transfer theory. The maximum difference between the measured and calculated fermentation temperature was 2%. The effect of biogas fermentation assisted by simple solar greenhouse in typical city of different climate zones, including severe cold region, cold region and hot summer and cold winter region, was studied with the combination of heat transfer model and temperature-based biogas production rates prediction model. The results showed that, the gas production rate of biogas fermentation increases with the increase of temperature in a certain range. Assisted by simple solar greenhouse, the biogas digester temperature is increased by 6~8°C compared with the previous one, ensuring a better daily gas production rate of 0.5~0.7m3/m3 in winter.

During the period of water shortage in the Republic, modern resource-saving irrigation methods and the use of purified and industrial waters and their reuse in irrigation is an urgent problem in ecology. Among the methods for treating industrial wastewater in a cheaper, cost effective way is the biological treatment method. It is the study of the effectiveness of biological treatment of industrial wastewater from primary winemaking using selected strains of aquatic plants (pistia). The object of wastewater research is selecting a Pistia algae strain, carrying out biochemical, hydrochemical analyses of wastewater before and after treatment, and the chemical composition of the Pistia algae biomass. All studies were carried out according to the standard studies of UzGOST for waste and drinking water and algological methods used by the Institute of Botany of ANRUz, State Enterprise "Institute GIDROINGEO", etc. The efficiency of biological purification of wastewaters of primary winemaking by higher aquatic plants of the pistia was established. With the help of the research carried out, the wastewater treatment of the food plant, in particular, the Kibray wine station with the Pistia algae, was established: the optimal parameters of growth, development and purification capacity of pistia algae were established for various variants of experiments and wastewater samples; designed and assembled a semi-industrial plant for biological wastewater treatment of the Kibray wine station and carried out work on industrial wastewater treatment. Wastewater from the Kibray wine station contains organic compounds, namely yeast sediments, proteins, fats, carbohydrates, fiber, which are food for Pistia algae. Pistia biomass obtained after cultivation in wastewater after sterilization can be used as feed in livestock and poultry farming, as it contains a large number of proteins, fats and carbohydrates.

High carbon footprints and limited availability of fossil fuels have motivated researchers to find alternatives to fossil fuels and the ways of producing them. Hydrogen is an alternative fuel and can be generated by electrohydrogenesis in a Microbial Electrolysis Cell (MEC) using wastewater. At times, the microorganisms known as exoelectrogens are added externally to the wastewater in the form of biomass. Biomass serves as a parameter to optimize the yield of hydrogen. In this research work an attempt is made to understand the effect of the biomass concentration on the substrate utilization by the exoelectrogens and product formation. This research work also aims at studying the biochemical reaction kinetics and to identify a model that best describes the kinetics of the reactions involved, at the electrodes. It was observed that on increasing the biomass concentration from 0.7g/L to 1.4 g/L, the gas liberation rate increased from 9.42 ml/day to 15.33 ml/day and substrate utilization increased from 86.8% to 94.3%. This was in close agreement with the solution of the identified model. It was found out that the energy efficiency of MEC improved substantially by 30% and the energy demand was decreased by 38.5% when the initial biomass concentration was doubled.

The daily needs of energy in remote areas, Indonesia, is dominated by biomass waste. The abundant types of biomass waste for heat transfer is empty fruits shell (EFS) of oil palm as briquette. This research discussed a brief analysis of oil palm shell by using physical treatment at different crushing pressure. It was also to examine the adequate size of particle for improving the heating value of briquette. The crushing pressure had a height dimension of 20 cm, as well as the briquette mold with a diameter of 2 cm and a height of 1 cm. The oil palm shell which was applied physical treatment at different crushing pressure of 400 J, 550 J, and 700 J, that resulted in particle size is smaller than 800 µm, 800 µm to 1 700 µm, 1 700 µm to 2 000 µm, and bigger than 2 000 µm. The adequate size of particle for briquette was found to be < 800 µm, which reached the heating value of 20 042.32 J g–1 and ash residue of 20 %. This study showed the advantages of oil palm shell briquette by using physical treatment is suitable and sustainable alternative to daily life use in Indonesia.

Biomass pyrolysis is an advanced process which leads to obtaining products as chars, primary tars and gases. Depending on pyrolysis conditions and reactor construction, the pyrolysis could be divided into three categories: slow, intermediate and fast. This work concerns the experimental analysis of an intermediate pyrolysis of biomass residues in a fixed bed reactor. As raw materials, pine bark and wheat straw were selected. Experiments were carried out at three temperatures: 400, 500 and 600 °C under constant volume flow rate of inert gas equal to 100 ml/min. Biomass samples were kept for 150 seconds in the hot zone. The main goal was to compare yields, elemental composition, and calorific values of received products under studied process conditions. The ultimate analysis of chars and organic fractions of oils was performed. Obtained results from ultimate analysis allowed to determine higher heating values by a theoretical correlation. The products of pyrolysis obtained at 600 °C characterized by the most energetic parameters. The higher heating value for organic fraction of tars was 31.62 MJ/kg while for char was 29.47 MJ/kg.

Biomass from palm empty fruit bunch (EFB) is considered as potential renewable energy sources to be developed in Indonesia. Palm EFB can be efficiently converted into valuable and useful methanol products through gasification. Research about methanol synthesis from various biomass has been done. However, Little research about methanol production based on palm empty fruit bunch gasification has been found, and no research yet on technoeconomic analysis of methanol plant construction based on palm empty fruit bunch gasification. The purpose of this research is to find early-stage feasibility of small-scale methanol plant model based on gasification of palm EFB. Method methanol plant design, investment cost estimation, operating cost estimation, and calculation to estimate profitability in terms of economic feasibility parameters. Economic analysis calculated that the total investment to build a methanol plant in this study was USD 87 508 479 with manufacturing cost per annum USD 6 127 014. Net Present Value (NPV) calculated was USD -51 721 064 and IRR at 1.1 %. Based on NPV and Internal Rate of Return (IRR) value, the construction of methanol plant is not feasible. Feasibility predicted to be obtained when the capacity of the plant increased fivefold.

The use of algae is gaining popularity in recent years. Algae can form a suitable substrate for biogas production because they are low in cellulose and have low lignin content. The paper contains a summary with the list of the algae species applied for the biogas production process to this date, coupled with the description of the characteristic conditions in which the process is conducted. The key importance factors during the production of biogas include, among others, grade of algae species used, temperature of the process, mode in which the material is supplied into the tank, mixing method, use of co-substrate, etc. This paper reports the results of the study involving the effect of various temperature conditions on the characteristics of the growth rate of algal biomass. The research was performed for the Chlorella vulgaris BA-0167 strain in the temperature range corresponding to the mesophilic fermentation processes in anaerobic conditions.

The objectives of study were to investigate the ash content, carbon content and the higher heating value and modelling of HHV of forest and agricultural biomass. Five types of biomass were used for the experiments: sunflower husk pellets, wood pellets, straw and hay briquettes, and forest chips. The investigated biomass properties (their average values) change: for ash content between 1.3% (woods pellets) and 7.3% (hay briquettes), for carbon content between 37.4% (forest chips) and 52.0% (wood pellets), for HHV between 14.8 kJ/kg (forest chips) and 20.1 kJ/kg (sunflower husk pellets). Two mathematical models from literature and model proposed by the authors were used to the HHV calculation. The model proposed by the authors gave the best results in determination of sunflower husk pellets HHV.

The aim of this work was to investigate the biomass proliferation and its impact on the operation of a submerged membrane bioreactor (sMBR). A programmable logic controller (PLC) was used to control the process of the sMBR with no discharge of sludge. When MLSS was 9670 mg/L and the solid retention times (SRT) ranged from 20 to 40 days, the optimal removal efficiencies of COD, NH3-N, TP were 93.89%, 93.02%, 80.57%, respectively. Accompanying with the decreasing of the sludge loading, the substrate and nutrition were insufficient in the sMBR, leading to endogenous respiration of the activated sludge, which decreased the activity of sludge and resulted in the death of more microorganisms.

This article discusses the possibility of using cheap raw materials for the treatment of wastewater from heavy metal ions using residual biomass and agricultural waste (sunflower husk, millet, buckwheat). Residual biomass is formed after the extraction of valuable components from microalgae and duckweed. The authors proposed to modify the sorption material using heat treatment and the introduction of additives, such as chitosan and thermally expanded graphite. Chitosan allows you to get sorption materials in the form of granules, which are convenient to use. The physicochemical properties of sorbents were studied. The sorption capacity for the obtained materials was from 5.0 to 32.0 mg/g.

The article presents the results of evaluating the ability of activated sludge, saturated with anammox bacteria, to adapt to mesophilic and lower temperature operating conditions. As the main temperature regimes, temperatures of 30, 25, 15, and 13°C were selected. The system has demonstrated stable operation at temperatures about 15°C with the highest degree of purification for ammonium nitrogen - 0.33 mg/L. At the same time, the concentration of nitrites reached 0.07 mg/L taking into account forced nitration. An additional increase in the efficiency of the system requires structural changes in the adopted technological scheme of the bioreactor, however, the introduction of an internal system of recirculation of attached biomass (with load) inside the anammox compartment is considered as an essential element of the system that ensures stability.

Fuel pellets made from biomass is considered as a solid fuel that is also an alternative fuel which can substitute for the current fuels and can be considered as a fuel that has sustainable production. This research is the study of the production of fuel pellets from Teak sawdust blends with Cajuput leaves at five proportions by weight of Teak sawdust 100%, Cajuput leaves 100%, Teak sawdust 75% +Cajuput leaves 25%, Teak sawdust 50% +Cajuput leaves 50%, Teak sawdust 25% +Cajuput leaves 75% . The pellets were produced by a grinding and pelleting machine at three different speeds of 200, 250, and 300 rpm. After that, the quality of fuel pellets was evaluated by the physical properties as pellet dimensions, particles and bulk density, as well as moisture content and durability. The results show that blending proportion of Teak sawdust 75% and Cajuput leaves 25% provided the appropriate fuel pellet properties.

Greening waste presents considerable reuse potential owing to its simple organic composition. For greening waste, being simply regarded as ordinary garbage cannot adapt to the requirements of sustainable and harmless development. Resource reusing process is an inevitable trend. Utilization of urban landscape greening waste is of great significance for improving the ecological environment in urban and rural areas, building a harmonious city, increasing employment, and enhancing economic efficiency. This will be a far-reaching impact on China's economic and social sustainable development. In this work, eight typical landscape plants were selected as raw materials using the batch reactor. The concept of stepwise hydrothermal conversion and a real model with xylose, cellulose acetate (CA), and aromatic aldehyde as the target products were thereby constructed. In the third step of the stepwise conversion, the effect of reaction temperature and time in the oxidative degradation of cellulose acetate solid residues in NaOH solution to produce aromatic aldehyde was investigated. The optimum conditions were obtained as 175 ℃ and 90 min. The yield of aromatic aldehydes in all 16 branches and leaves of cellulose acetate all reached about 20% under the optimal conditions.

Growing demand for energy and care about natural environment is the motivation to find alternative sources of energy. One of them is biomass from cherry and morello cherry stones, which is food processing industry waste. Stones have fairly good physical properties regarding material for combustion. Cherry and morello cherry crop in Poland is at the level of 200 thousand tons yearly, and processing them generates a considerable amount of waste that consists of stones, which may be used for energy purposes. In the work, the initial water content (u), curves of combustion in different temperatures, percentage ash content, heat of combustion and percentage share of stone in the whole fruit were determined.

Biomass is a central issue as new material that can be used as a substrate to produce biofuels, it has become global research to replace liquid fossil fuels with alternative renewable and sustainable fossils. Palm oil mill effluent (POME) is the potential of Agri-industrial waste to be used as alternative energy with anaerobic digestion of high concentration organic wastewater can be used for bioethanol production to replace food as raw material. Bioethanol can be produced in acidogenic steps in the organic degradation process. In this research, bacterial mixed cultures sourced from bovine rumen as biomass and the substrate used was palm oil mill effluent (POME) with a characteristic COD concentration of 25,600 mg/L, The operation of the reactor is set at pH 5; 6; 7 for 72 hours with the type of anaerobic circulating batch reactor (CBR), measurement of bioethanol products and acidogenesis of samples is carried out every 6 hours. The results showed that the reactor with variations in pH conditions 5 gave the highest efficiency of bioethanol formation in the 12 hour running process, result is 102,94 mg/L with a maximum formation rate of 9,98 mg/L/hour.

There are plenty of biomass resources in Thailand such as agricultural residues from plantations and industrial or woody processes. Biomass in the form of a pellet has more energy density than the original form moreover it is easier to handle and has a higher strength. This study selected woody parts from commonly found trees in Southern Thailand, fuel pellets were made to examine the physical properties and microstructure. Para-rubber (Hevea brasiliensis Muell. Arg.) sawdust and the branches and leaves of She Oak (Casuarina Equisetifolia) and the Cajuput tree (Melaleuca Cajuputi) were collected from the local area to make pellets by a single unit pellet mill at 130oC and 450 psi of compression temperature and pressure, respectively. The physical properties were characterized via pellet density, moisture content, heating value and compressive strength. Moreover, the microstructure of cross section area of pellet samples from the scanning electron microscope (SEM) pictures were proposed to observe the bonding mechanism. The results show that the different raw material provided different properties. The highest pellet strength, density and heating value was achieved from Cajuput leaves.

The purpose of this work was to study the gas yield variation resulted from the cherry wood gasification with air using a lab-scale rotary kiln gasifier. The feedstock was continuously fed into the preheated reactor at 600°C, in co-current configuration, using atmospheric air as a gasifying agent. The results indicate the importance of oxidation reaction control, through the feeding flow rates of biomass and air and the reactants mixing rate. From the experiment, the hydrogen yields were about 2-4%, while the carbon monoxide varied between 8-21%. Additionally, the paper provides process observations based on the continuous monitoring of gas composition. The specific flow rates of substances and installation operating conditions were linked to process run through syngas composition.

Biomass is doubtless a very significant source of renewable energy being worldwide abundant with high energy potential. This paper deals with assessment energy consumption at especially grinding and briquetting processes, which should result in essential economy of energy at solid biofuel production. Various types of raw materials were used at the experiment such as hemp (Cannabis sativa L.) biomass, two species of Miscanthus (Miscanthus sinensis, Miscanthus x gigantheus) and apple wood biomass. These materials were dried, grinded and pressed by piston press having pressing chamber diameter of 65 mm. Materials were grinded into three fractions (4 mm, 8 mm and 12 mm). Material throughput (kg.h-1) and energy consumption (kWh.t-1) were registered. As to results: the highest throughput at both grinding cases as well as briquetting was found at apple wood biomass; however the energy consumption during briquetting of apple wood was relatively high. The worst results concerning throughput and energy consumption (especially at briquetting) were found at hemp biomass. Nevertheless, briquettes made of hemp had the best mechanical durability. Both Miscunthus species (herbaceous biomass) have very similar parameters and showed quite good relation between throughput and energy consumption at the used machines.

The paper presents the results of research aimed at determining the influence of the composition of the fertilizer mixtures and the compaction pressure on the specific density and density index of fertilizer granules. Investigated mixtures were prepared from fly ash from power plant fuelled by biomass and digestate from biogas plant. The urea, sulfur and phosphorite were also added as enhancing additives. For granule samples made on a strength machine, their specific density was determined on a quasifluid-pycnometer. To determine the effect of agglomerate pressure on the compaction process, the absolute density of the materials was omitted. In such case it was needed to introduce a density index AI. Such a presentation of the results obtained has made it possible to clearly determine how the density of the test mixture results in the applied agglomeration pressure. The specific density of the resulting granules was in the range of 0.85-1.27 g/cm3. The determined density index for the given pressure was in the following ranges: 0.44-0.49 g/cm3 (pressure 100MPa), 0.47-0.51 g/cm3 (pressure 150MPa) 0.51 - 0.59 g/cm3 (200MPa pressure). This means that, regardless of the contribution of components to the mixture at the given pressure, a similar degree of compaction was obtained.

In the long-run, microwave pyrolysis can be a simpler and low energy-requiring alternative to conventional pyrolysis for the thermochemical conversion of biomass to useful products. However, there are still research gaps in its mechanism. Thus, this study investigated the various factors affecting the biochar yield using a half resolution (2k-1) factorial design on the microwave pyrolysis of corn cob wastes. A viable biochar product was produced within minutes of the reaction; wherein, the statistical analysis confirmed the exposure time, microwave output power and their interaction as significant in the CCBc yield. The highest yield obtained was 52.87% when exposure time and output power were set to 5 min and 450W, respectively. A general decreasing effect on the yield was observed from increasing exposure time and output power. This was due to the rapid heating experienced by the corn cob wastes causing the hydrocarbons to react and transform into permanent gases at higher temperatures. To confirm the carbon content of the CCBc, elemental analysis showed an average of 67.11% C at low time-low power (LTLP) of 450 W for 5 min and 81.32% C for the samples operated at high time-high power (HTHP) of 700 W for 10 min.

The advanced energyand resource saving technologies of food production wastewater treatment include anaerobic and aerobic steps. At present, various methods of intensification and optimization are used to increase the efficiency of anaerobic processes of wastewater treatment, including selection of active microbial communities, providing the optimum temperature regime, immobilizing biomass by granulation or biofilm formation, reducing various inhibitory effects, phase separation or pre-acidification, chemical or biological pretreatment of wastewater. The aim of this investigation was researching the effect of hydraulic and organic load rates on the energy efficiency of the wastewater treatment process and evaluating the energy efficiency depending on process conditions. Experimental laboratory installation included subsequently connected bioreactors, one from which acted as first stage and other bioreactors as the second stages of anaerobic process. It was shown that the biogas formation at the first and second stages differs significantly. A small volume of released biogas on the first stage allows us to ignore it, but characteristics of biogas formation at the second stage bioreactors are close and are described by general functional dependence. The specific yield of biogas from the organic matter consumed Ybgis independent of the specific organic load rate L, but is dependent on the specific flow rate of the treated water D.

Biomass briquettes have been made as an alternative energy source from cow dung waste. Molasses and starch were used as binder material with a carbonization temperature of 400 °C for 2 hours. The work aims to produce biomass briquettes with the best heating value based on analysis of composition effect and type of binder on the briquette with calorific value. The heat test results showed that briquettes with 10% sugar cane binding content produced the highest calorific value of 3907.5 calories/gram. Sugar cane drops become the better binder than starch in biomass briquettes production.

Alkaline pretreatment has been known as the most popular method to process lignocellulosic materials for bioethanol production due to its simplicity and high efficiency. However, the waste water of the process has a very high basicity, which requires neutralization with acids upon further disposal. In this study, rubber wood saw dust (Hevea brasiliensis) was employed as lignocellulosic material and its pretreatment was inspected with both diluted H2SO4 and NaOH in different combination ways. Hereby, acid was used not only for waste water neutralization but also to contribute to lignin removal. Analysis results showed that an aqueous solution of 2.0 - 2.5 wt.% H2SO4 can be used to treat the biomass followed by alkaline pretreatment. By this so-called combo-pretreatment technique, cellulose was well preserved without significant hydrolysis while the final pretreatment efficiency was up to 63.0%, compared to 48.2% of using only the alkaline solution and 13.7% of using only the acidic solution. Finally, alkaline waste water can be mixed to be neutralized with acidic waste water from the two previous steps. This innovated technique improved the pretreatment efficiency almost without increasing in chemical cost.

Harvesting of microalgae is one of the main challenges in the production of biodiesel due to the small cell size of microalgae cells. Chemical flocculants have been generally used in the harvesting of microalgae, but they are harmful to the environment and relatively costly. Therefore, the utilization of waste biomass in producing bioflocculants is the current research niche to introduce environmental-friendly harvesting method and to minimize the cost of biodiesel production. Thus, in the current work, flocculation Chlorella vulgaris using mild acid-extracted bioflocculants from miscellaneous waste biomass (cockle shell, peanut shell and banana peel) were conducted by varying the pH values, the dosage of bioflocculants and temperatures. Cockle shell bioflocculant demonstrated the best flocculation performance, with highest flocculation efficiency of 85.2% compared to the peanut shell bioflocculant with flocculation efficiency of 37% and banana peel bioflocculant with flocculation efficiency of 16.3%. The optimum flocculation conditions for cockle shell bioflocculant were determined as follow: pH 9, bioflocculant dosage of 140mg/L and temperature of 30oC. The findings herein presented practical applicability of bioflocculants extracted from cockle shell for safe, rapid and inexpensive microalgae harvesting.

The article presents the features of conservation of leafy mass of high-protein crops of the legume family, the disadvantages of traditional preparation of biomass for silage in fodder production. The results of studying the possibility of reducing plant moisture by mechanical means, using the press residue as a raw material for making haylage, and brown juice as a preservative are presented. The results of the development of a method for silage of the pressed alfalfa residue with the introduction of fermented brown juice enriched with the metabolic products of lactic acid and propionic acid bacteria - organic acids, to intensify the process of fermentation of feed. The analysis of the chemical composition of plant raw materials and the obtained haylage was carried out, the value of fodder, energy value and potential harmlessness for feeding to animals was determined.

The problem of improving the environmental safety of the waste management system of chemical processing of biomass of wood is quite acute in every forest producing and timber processing region. Study of the possibility of using to investigate hydrolytic lignin as a modifier of phenol-formaldehyde resin for the production of plywood have been conducted. Used materials: phenol-formaldehyde resin SFZh-3013; technical hydrolyzed lignin. Mathematical models of the process of pressing glued plywood were developed and the optimal parameters for the production of plywood were determined based on the use of SFZh-3013 resin modified with hydrolytic lignin. The optimal mode of pressing is: the amount of injected hydrolytic lignin in the SFZh-3013 resin grade is 5-10 parts by weight; pressing pressure 1.6 MPa, pressing temperature 135 °C and pressing time 9-10 minutes. The introduction of regimes developed using regression equations, with a sufficient degree of accuracy describing the pressing process, will significantly improve the efficiency of plywood production by saving energy and material costs and preserving product quality.

Most of the agricultural wastes in developing countries are disposed of by on-site combustion leading to unmanaged environmental pollutions. Conversion of agricultural wastes to value-added products, such as bioethanol and biogas, is a promising method to reduce agro-waste after harvesting seasons. In this study, Citrus maxima peels (Pomelo peels) was selected to be converted to reducing sugars, which could be a raw material to produce other value-added products. To promote enzymatic hydrolysis reactions, pomelo peels were pretreated with sodium hydroxide by variations of three pretreatment parameters, including temperature (50-100 ºC), time (0.5-6 h), and concentration of NaOH (0.5-3.0 M). Box-Behnken design (BBD) was applied in Response Surface Methodology (RSM) to determine the optimized pretreatment condition and to find the relationship between pretreatment factors and reducing sugar yields. The predicted optimal pretreatment condition was determined to be at 94.28 ºC, 4.5h, 2.17M with reducing sugar yield of 98.9 mg/g of dried pomelo peels. The results clearly showed that reducing sugar yields obtained from pretreated pomelo peels were 1.87 folds higher than untreated biomass (52.81 mg/g of pomelo peels). Therefore, this study demonstrated the potential of pomelo peels to be used as an alternative raw material for value-added products rather than being a landfill or causal agent of pollution.

Agricultural wastes as Biomass contains low carbon, high hydrogen, high oxygen and a lower amount of sulfur. Coals contain higher amounts of carbon, lower amounts of hydrogen, lower oxygen and higher amounts of sulfur. With the use of lignite and biomass mixture as fuel will provide less CO2 and SO2 emissions and a more economical mixture will be obtained. Considering these emissions, fluidized bed combustion systems are recommended in the literature for the combustion of lignite and biomass. In this study, rice husks, corn cobs, walnut shells, sunflower shells, olive cake and woodchips were used as agricultural waste. 10 different lignite extracted from Turkey were used as fuel. It has been assumed that the combustion process was carried out by taking the biomass rate of 10%, 30% and 50%. When burning of 1 kg of lignite and biomass mixture, the highest CO2 emission occurs from 10% woodchips - 90% Kütahya - Ömerler (washed) mixture as 2.938 kg and the highest SO2 emission obtained from 10% olive cake - 90% Kütahya Seyitömer-Ayvalı lignite mixture as 0.061 kg. The highest H2O emission was obtained by mixing 50% woodchips - 50% Manisa-Kısrakdere lignite as 0.563 kg.

The paper presents the results of research on gasification of olive pits and production of a generator gas with calorific value enabling its combustion in microturbines. Gasification was carried out in a laboratory gasification reactor, where the converting factor was air. The influence of the flow rate of its stream on the composition of the generator gas was investigated. The research involved searching for optimal process conditions for gasification of this biomass, to obtain a generator gas with an increased CH4 content (methane is the most calorific component).The air flow in subsequent tests was 0.5m3/h, 0.85m3 /h, 1.1m3/h,. 1.4m3/h 1.7m3/h. The quantitative composition of the generated generator gases differed. These conditions were obtained with an air flow of 1.4m3/h, in a tubular reactor, at the bed temperature T3= 456–462oC. A gas was obtained, with a calorific value of 9.2MJ/m3, characteristic for the following gas composition: H2=3.88%, CO=18.52%, CO2=6.27%, CH4=16.02%, O2=1.28%.

The paper presents the effects pelletization process of torrefied waste forest biomass – sawmill wastes. The sawmill waste are generated in significant quantities and has significant energy potential. The use of torrefaction and pelletization process enables to produce mechanically durable fuel pellets. Aim of the studies was to evaluate the effect of different kind of additives (binders) to torrefied waste forest biomass on pelletization process characteristic (production capacity, energy consumption) and properties of produced pellets (i.e. density, mechanical durability). The most effective binder among the tested was modified wheat starch. Pellets made with this addition were characterized by the highest mechanical strength.

In modeling studies, estimation of microorganisms kinetic parameters set is a key element for proper model operation and predictability. Nitrification process is very often, a crucial element of the wastewater treatment systems as bacteria responsible for ammonium and nitrite oxidation are slow growing microorganisms, making whole nitrification process vulnerable to external factors i.e. temperature, inhibition and load fluctuations. Growth and decay rate of nitrifiers decide about amount nitrifying biomass in the wastewater treatment plants, thus the nitrification efficiency. Paper presents analysis of the decay rate (ba) estimation methodology based on respirometric assays measuring the oxygen uptake rate (OUR). Evaluation of this simple and cheap method was made based on decay estimation tests performed on sludge samples from side-stream partial nitritation reactor treating reject water from digested sludge dewatering. Database obtained from these tests were analyzed to evaluate the impact of respirometric assay duration on calculated decay rate values. 11 time ranges were selected for the performed analysis. Calculated ba values were compared showing the optimal test duration between 5–6 hours, while test shorter than 2 hours resulted in unsatisfactory ba outcome.

Scots pine (Pinus Sylvestris) is a very popular tree species in north-eastern Poland. Pines are frequently encountered in allotment gardens in the proximity of residential buildings. Pine biomass should not be composted because the produced humus has acidifying properties. For this reason, the management of pine waste biomass poses a problem. The article proposes a solution for managing pine waste biomass for heat generation. In the study, pine waste biomass was composed of needles, cones and dry branches. The biomass potential of Scots pine was determined. Waste biomass was harvested in spring when most allotment gardens are cleared after winter. The biomass yield of several trees was determined (in kg and dm3), and the average yield per tree was calculated. The average proportions of different biomass fractions in mixed waste biomass were also determined. The specific heat of different biomass fractions (needles, branches, cones) was determined for two scenarios. In the first scenario, waste biomass was harvested during a prolonged dry spell, and in the second scenario, waste biomass was harvested immediately after rainfall. The energy potential of waste biomass was determined. The harvested biomass was burned in an open fireplace in a cottage with an area of 48 m2. The time required to burn 10 m3 of biomass and the resulting increase in indoor temperature were measured. The environmental impact of burning Scots pine biomass was determined.

Increased interest in renewable, carbon-neutral energy sources makes processing biodiesel from microalgae has become the objective for many researchers and companies. Some kind of wastewater including municipal, industrial and agricultural wastewaters have been identified as alternate growth mediums. Produced water is the largest byproduct of the oil and natural gas extraction process which constitutes of high concentration of pollutants, such as dissolved nitrogen, phosphorus, dissolved organic carbon, heavy metal and monocyclic aromatic compound like BTEX. The purpose of this study is to identify Chlorella sp. potential for producing lipid in artificial produced water. Variations made in this study consist of 0%, 25%, 50%, 75% and 100% volume of artificial produced water to the control Walne medium. The highest specific growth rate and biomass productivity of Chlorella sp. achieved by culture grown in 25% wastewater with a value of 0.225 day−1 and 0.175 g L−1day−1, respectively. The highest lipid yield and productivity in mixed culture of artificial produced water and Walne medium achieved by culture in 25% artificial produced water with value of 0.231 and 40.48 mg.L−1.day−1. C16 and C18 fatty acids which dominated the lipids of Chlorella sp. in all culture variations indicated that the lipid of Chlorella sp. were suitable for producing high quality biodiesel.

An experiment on the production of biochar from bamboo scraps and hardwood chips for use as materials to improve soil was done by burning the biomass of the bamboo scraps and hardwood chips in Pyrolysis conditions at a temperature range of 500 - 700C with a cone-truncated open fire kiln which reduces burning time to 45-60 min. Experimental results revealed that the average bamboo-scrap biochar of 2.5 kg resulted from burning 15 kg of the bamboo scraps; likewise, the average hardwood-chip biochar of 2.2 kg resulted from burning 15 kg of the hardwood chips. According to analyses, the bamboo-scrap biochar was composed of 8.6% moisture content, 8.0% volatile substance, 9.0% ash, 83% fixed carbon, 250mg/g iodine and pH 10.3; whereas, the hardwood-chip biochar was composed of 6% moisture content, 8.2% volatile substance, 3% ash , 88.8% fixed carbon, 300 mg/g iodine, and pH 10.1. The result of planting experiments showed that after mixing the biochar for soil nourishment and compost into the planting soil, the morning glory and kale can grow better than those planted in normal soil and soil with compost.

Bioconversion of C-1 carbon in syngas through microbial fermentation presents a huge potential to be further explored for ethanol production. Syngas can be obtained from the gasification of lignocellulosic biomass, by which most of carbon content of the biomass was converted into CO and CO2. These gases could be further utilized by carbon-fixing microorganism such as Clostridium sp. to produce ethanol as the end product. In order to obtain an optimum process, a robust and high performance strain is required and thus high ethanol yield as the main product can be expected. In this study, series of batch fermentation was carried out to select high performance strains for ethanol production. Bottle serum fermentations were performed using CO-gas as the sole carbon source to evaluate the potential of some Clostridia species such as Clostridium ljungdahlii, C. ragsdalei, and C. carboxidovorans in producing ethanol at various concentration of yeast extract as the organic nitrogen source, salt concentration, and buffer composition. Strain with the highest ethanol production in the optimum media will be further utilized in the upscale fermentation.

Indonesia has a huge potential rice husk waste of 150 GJ/year, a third more than the overall potential of biomass in Indonesia of 470 GJ/year. Gasification of small-scale biomass fixed bed downdraft becomes one of the best solutions to become energy for power and heat generation. From studies that have been conducted abroad and from previous studies, the use of double stage air intake on the reactor proved effective in reducing tar because tar formed from the pyrolysis zone must pass through two zones below before then out with the gas producer. Implementation of secondary air intake at position Z = 38 cm right on the pyrolysis zone, obtained results at ER 0.25. With the same size, as much as 80.82% with tar content on the producer gas of 11.62 grams/Nm3. While at ER 0.23 figures found the highest gasification efficiencvby 33.41%.

This study describes properties of biomasses of Moringa oleifera Lamarck for energetic applications of production of biodiesel and briquettes. The seeds collected of the mature pods were the initial biomasses used of this plant. The seeds were separated into husks and oilseed grains, from which the oils were extracted by mechanical pressing and by solvent extraction. The crude oil mixed (of pressing and by solvent) was degummed, neutralized, washed, dried and characterized. The purified oil was converted into methyl biodiesel in homogeneous alkaline transesterification, which was purified and characterized. The residual peels and pies had their calorific powers measured and compared with classic agricultural residues: firewood, sugarcane bagasse and coconut husks. Moringa culture was compared to soybeans in agricultural and biodiesel production perspectives. The analytical results show that the biomasses of the moringa are favorable as renewable biofuels like biodiesel or briquettes due to the good calorific power and simple and accessible productive technology. The production of briquettes starting from the biomasses of the moringa would be recommended with the uses of the pod husks, seed peels and pies (cakes) of extraction of the oil. The agricultural management and the simple productive technologies applied to the moringa are favorable for social inclusion by enabling family agriculture.

Coal can be used to produce hydrogen through steam gasification process. Indonesia has abundant coal reserves and thus hydrogen production from coal is very attractive. However, steam gasification of coal usually requires high temperature due to its low volatile content. The use of catalyst, such as alkaline and alkaline earth metal (AAEM) may promote the hydrogen production. AAEM metal can be found in biomass and thus co-gasification of coal and biomass may become the attractive solution as the AAEM may volatilize during gasification and catalyze the coal when it attaches to the coal surface. However, the presence of silicate may decrease catalytic activity of the attached AAEM and thus it needs to be removed by deashing process. This research aims to determine the effect of the solution type, solution concentration, reaction temperature, and reaction time of coal deashing. The results showed that deashing process decreased the ash content of coal to some extent proved by the gravimetric analysis result. The decrease of ash content also affected to the surface morphology of the coal as some pores are formed and thus the surface area of coal increased slightly. The increase of surface area allows more AAEM to be attached to the coal surface so that the coal may become more reactive towards steam gasification.

The utilization of Indonesia low rank coal should be maximized, since the source of Indonesia law rank coals were abundant. Pyrolysis of this coal can produce liquid product which can be utilized as fuel and chemical feedstocks. The yield of liquid product is still low due to lower of comparison H/C. Since coal is non-renewable source, an effort of coal saving and to mitigate the production of greenhouse gases, biomass such as oil palm empty fruit bunch (EFB) would added as co-feeding. EFB could act as hydrogen donor in co-pyrolysis to increase liquid product. Co-pyrolysis of Indonesia low rank coal and EFB were studied in a drop tube reactor under the certain temperature (t= 500 °C) and time (t= 1 h) used N2 as purge gas. The effect of blending ratios of coal/EFB (100/0, 75/25, 50/50, 25/75 and 0/100%, w/w %) on the yield and composition of liquid product were studied systematically. The results showed that the higher blending ratio, the yield of liquid product and gas obtained increased, while the char decreased. The highest yield of liquid product (28,62 %) was obtained used blending ratio of coal/EFB = 25/75, w/w%. Tar composition obtained in this ratio is phenol, polycyclic aromatic hydrocarbons, alkanes, acids, esters.

The present article relates to assessment of energy utilization of sweet sorghum waste biomass as solid biofuel (briquettes). The briquettes were produced from biomass of pure sweet sorghum after juice extraction, mixture of sorghum with wood sawdust (ratio 1:1) and mixture of sorghum with wood shavings (ratio 1:1). Chemical, physical and mechanical properties of produced briquettes were measured in accordance with appropriate standards. The research results showed that the mixed sorghum briquettes with wood shavings have the highest mechanical durability and the lowest ash content; on the other hand, briquettes made of sweet sorghum and wood sawdust havethe best values of all other parameters, including higher calorific values, density, etc. Although addition of residual wood biomass improved the general quality of sorghum based briquettes, it was stated that the briquettes made of pure processed sorghum stalks belong to the category of high quality agricultural solid biofuels. It can be concluded that sweet sorghum is of very good prospects and thus it is a promising biomass feedstock for solid biofuels production (not only for the production of liquid biofuel as it has been used by today and has been known before).

The crucial problem facing the world today is energy resources. Waste production of palm oil fruit bunch potentially produce as renewable energy resource. Palm oil fruit bunch contains 44% cellulose, 18% lignin and 34% hemicellulose. Organic carbon source is contained in biomass potentially produce biogas. Biogas is one of alternative energy, which is environmentally friendly and has been widely developed. This research is aimed to examine the effect of pretreatment in raw material of waste palm oil fruit bunch for the production of biogas, the effect of time, ratio C/N, and effect of microbial consortium. The variables are total solid (TS) used 10% and 18% with a 40 mesh physical pretreatment, chemical pretreatment with NaOH 8% gr / gr TS, and biology 5% g/vol with microbial consortium. Biogas production process was conducted over 2 months in room temperature, the test response quantitative results in the form of biogas volume every 2 days and also flame test. The result of this research shows that the highest daily production rate of biogas obtained from this study was 5,73 ml/gr TS and the highest biogas production accumulation generated at 58,28 ml/gr TS produced through a 40 mesh sieve of waste oil palm empty fruit bunch, immersion in NaOH, through solid state fermentation and C/N 30. From this research, it can be concluded that the optimum production of biogas formation occurs with the value of C/N 30, physical and biological pretreatment, and solid state method.

Oil Palm agroindustry is growing rapidly in Southeast Asia especially Indonesia and Malaysia. Based on GAPKI data, Indonesia's CPO production 2017 is 38.17 million tons and PKO of 3.05 million tons. Production activities in palm oil agro-industry in addition to producing PKO and CPOl produce solid waste from the plantation and palm oil mill, Palm Oil Mill Effluent (POME) from the palm oil mill. The biomass waste of oil palm agro-industry comes from activities in plantations in the form of midrib, leaves and palm tree trunks. While from the palm oil mill produced solid waste in the form of palm kernel shells (PKS), mesocarp fibers (MF) and empty fruit bunches (EFB). The waste is classified as biomass residue that can be utilized so that it has added value. Biomass potential in Indonesia can be estimated from the productivity of oil palm. The volume of biomass is 5,5-8%, empty bunches 20-23%, palm fronds 13.5-15%, 15% palm fiber from 1 ton of fresh fruit bunches. The total potential of oil palm solid waste biomass in Indonesia 2017 is 20.07 million tons and POME is 23.7 million tons. The largest distribution of biomass is in Riau, North Sumatra, South Sumatra province.

The utilization of biomass as a source of new and renewable energy is being carried out. One of the technologies to convert biomass as an energy source is pyrolysis which is converting biomass into more valuable products, such as bio–oil. Bio–oil is a liquid which produced by steam condensation process from the pyrolysis of coconut shell. The composition of biomass such as hemicellulose, cellulose and lignin will be oxidized to phenol as the main content of the bio–oil. Production of bio–oil from coconut shell was investigated via fast pyrolysis reactor. Fast pyrolysis was carried out at 500 °C with a heating rate of 10 °C and 1 hour holding time at pyrolysis temperature. The Bio-oil chemical composition was investigated using GC–MS. Percentage value of phenol, 2–methoxy phenol, 3–methoxy 1,2–benzenediol, and 2,6–dimethoxy phenol was 45.42%, 13.37%, 10.09%, and 11.72% respectively.