Ethanol Production from Lignocellulosic Waste

Escalante, J. y Fuentes, H. (2013). Estudio experimental de obtencion de bioetanol a partir de residuos agricolas de banano organico en Piura. Tesis de pregrado en Ingenieria Industrial y de Sistemas. Universidad de Piura. Facultad de Ingenieria. Programa Academico de Ingenieria Industrial y de Sistemas. Piura, Peru. ESTUDIO EXPERIMENTAL DE OBTENCION DE BIOETANOL A PARTIR DE RESIDUOS AGRICOLAS DE BANANO ORGANICO EN PIURA

ABSTRACT: Currently, biofuels are the most significant alternative fuel aiming to provide clean power for transport, in case sustainable production technologies are employed. Due to the increased tendency of turning over the existing agricultural land to biofuel production, lignocellulosic feedstock is gaining increasing support against the use of first generation feedstock such as sugar cane, corn, wheat or sweet potatoes. However, despite the existing pilot plants, energy intensive technological processes like pretreatment and distillation, as well as high cost of enzymes, still prevent market roll-out of production facilities, extensive researches being conducted in order to find economically feasible alternatives. New close to market techniques, with improved performance in terms of energy and resources, are discussed: the relatively recent SPORL pretreatment, reported as the most effective in size-reduction energy consumption; pretreatment by means of extrusion - a technique in...

Currently, biofuels are the most significant alternative fuel aiming to provide clean power for transport, in case sustainable production technologies are employed. Due to the increased tendency of turning over the existing agricultural land to biofuel production, lignocellulosic feedstock is gaining increasing support against the use of first generation feedstock such as sugar cane, corn, wheat or sweet potatoes. However, despite the existing pilot plants, energy intensive technological processes like pretreatment and distillation, as well as high cost of enzymes, still prevent market rollout of production facilities, extensive researches being conducted in order to find economically feasible alternatives. New closeto market techniques, withimproved performance in terms of energy and resources, are discussed: the relatively recent SPORL pretreatment, reported as the most effective in size-reduction energy consumption; pretreatment by means of extrusion a technique in which biomass ...

The introduction of Feed-in tariffs in the German Renewable Energy Act (EEG) fuelled the growth of anaerobic digestion (AD) industry making Germany the country with highest number of operational AD plants. However, the rapid expansion of AD industry resulted in some unwanted side-effects such as food vs fuel debate, increased prices for electricity and the temporal mismatch between supply and demand of electricity grid. Subsequent amendments in EEG has tried to address some of these issues by reduction in Feed-in tariffs, introduction of a cap on cereal based feedstocks and providing premium for energy production in accordance with market demand. Furthermore, the Feed-in tariffs which were introduced for 20 years are soon going to expire. The changes in legal and political discourse is soon going to introduce some new challanges to the AD industry. This paper has discussed some of these challanges and their potential solutions.

As the world transportation is totally dependent on the petroleum fuels, the demand of the non-conventional energy is increasing day by day. So, it’s the time to look for approach other than tradition methods for the production of bioethanol. Keeping the facts of both the waste management and energy crisis bioethanol production from waste Lignocellulosic biomasses offers the cheaper and remarkable contribution. Newspaper as a lignocellulosic material was selected for study of bioethanol production. The alkaline pretreatment of the substrate was carried out, amount of the reducing sugar was calculated using DNSA method. The hydrolysate was then subjected to fermentation using Saccharomyces cerevisiae and Zymomonas mobilis (MTCC 2428), and ethanol concentration was estimated by using potassium dichromate method.

The aim of this study is to shed light on the importance of biofuels as an
alternative to conventional energy, in addition to the importance of
preserving agricultural crops, which are the main source of this fuel, to
maintain food security, especially in developing countries. The increase
in global oil prices, in addition to the fear of global warming, are among
the main factors that draw the world’s attention to searching for
alternative sources of traditional energy, which are sustainable on the
one hand, and on the other hand reduce carbon emissions. Therefore, the
volume of global investment in renewable energy in general, and in
liquid biofuels and biomass in particular, has increased. Global fears
emerged that the excessive conversion of large farms suitable for
growing food to energy production would threaten global food security.
In the first ten years of the new millennium, biofuel production increased
fivefold, and the largest increase in biofuel production was recorded in
2007-2008, coinciding with a sharp rise in food prices. Compared to the
average food prices in the period 2002-2004, the average global prices
of cereals, oils and fats traded were 2 to 2.5 times higher in 2008, this
continuous increase in the use of food crops to produce biofuels has
reflected on global food security. Accordingly, this review article will
address previous studies on biofuel production; identify the theoretical
framework for the concept of biofuels and its characteristics, and the
relationship between biofuels and food security. In this study, we
presented biofuels, which are considered one of the important categories
in the field of renewable energy and its environmental and economic
effects, as well as the experiences of some countries in its production,
and the possibility of benefiting from the natural resources available for
its production. We will discuss the scientific (chemical) principles of
biofuel production.

The increasing global demand for sustainable energy sources has directed attention to biofuel production from renewable resources. This study focuses on the synthesis and characterization of bioethanol from sawdust, an abundant lignocellulosic by-product, using microbial fermentation. Sawdust was pretreated with 0.5 M suphlfuric acid (H2S04) and subjected to microbial fermentation using Saccharomyces cerevisiae. After a week of fermentation at 30°C, the resulting bioethanol was extracted through distillation at 102°C. A 42% yield of bioethanol was obtained. Physicochemical characterization revealed a specific gravity of 0.82g/cm3, density of 1.05 g/mg, refractive index of 1.3441, cloud point of -15°C, acid value  39.3 mg KOH/g and Iodine value 2.5g 2.5/100g. Fourier Transform Infrared (FTIR) spectroscopy confirmed the presence of a prominent O-H stretching vibration at 3336.91 cm⁻¹ indicating hydroxyl groups characteristic of alcohols and 1635.46 cm⁻¹ to the C=O (carbonyl) stretching vibration. This study underscores the potential of sawdust as a sustainable feedstock for bioethanol production, offering a viable waste management solution and contributing to energy security. The results highlight the feasibility of integrating microbial fermentation with physicochemical processing to produce high-quality bioethanol while mitigating environmental challenges associated with sawdust disposal.

An anaerobic two-stage continuous fermentation process with combined thermophilic hydrogenogenic and methanogenic stages (two-stage fermentation process) was applied to artificial food wastes on a laboratory scale. In this report, organic loading rate (OLR) conditions for hydrogen fermentation were optimized before operating the two-stage fermentation process. The OLR was set at 11.2, 24.3, 35.2, 45.6, 56.1, and 67.3 g-COD cr L-1 day-1 with a temperature of 60 o C, pH5.5 and 5.0% total solids. As a result, approximately 1.8-2.0 mol-H 2 mol-hexose-1 was obtained at the OLR of 11.2-56.1 g-COD cr L-1 day-1. In contrast, it was inferred that the hydrogen yield at the OLR of 67.3 g-COD cr L-1 day-1 decreased because of an increase in lactate concentration in the culture medium. The performance of the two-stage fermentation process was also evaluated over three months. The hydraulic retention time (HRT) of methane fermentation was able to be shortened 5.0 days (under OLR 12.4 g-COD cr L-1 day-1 conditions) when the OLR of hydrogen fermentation was 44.0 g-COD cr L-1 day-1 , and the average gasification efficiency of the two-stage fermentation process was 81% at the time.

Vegetable oils and ethanol have been used in a plasmatron reformer to generate synthesis gas. Corn, canola, and soybean oils and ethanol have been reformed at different oxygen to carbon ratios and different power levels. Both homogeneous plasma reforming (uncatalyzed) and catalytic plasma reformer have been evaluated.

Sugar cane processing generates large amount of bagasse. Disposal of bagasse is critical for both agricultural profitability and environmental protection. Sugar-cane bagasse (SCB), being renewable and cheap substrates, has the potential to displace fossil fuels for the production of fuels and value-added chemicals. In this study, a complete degradation for SCB using chemical and biological methods was done to maximize its utilization. Chemical treatment degraded SCB into wax, cellulose, hemicellulose and lignin. Further hydrolysis was carried out by biological treatments using different microbial isolates obtained from different localities in Egypt. Out of one-hundred and twelve bacterial isolates, 40 isolates showed better performance for SCB biodegradation, based on the recoverd reducing sugars. Data analysis was carried out with PRIMER 6 (Plymouth Routines In Multivariate Ecological Research) to analyze species diversity against substrate degradation rate. Isolate CS5 was selecte...

This work was based on the pretreatment of lingo-cellulosic wastes from agroforestry organic wastes with samples being taken from stations of different sources. Between many of recommended and explained methods for pretreatment of the organic biomass we selected as the most effective, the way of acidic waste pretreatment and another scenario applying the alkaline method prior to the biodegradation through anaerobic bio-digestion for energy profit. For bio-methane profit process has been performed in a series of the experiments. From the various experiments we realized the great importance of the pre-treatment process for the biogas production. Alkaline pretreatment (with NaOH) brought about a decay of lignin structure of biomass and increase access of enzymes in hemicellulose and cellulose. This method was more effective than acidic treatment due to the fact that was achieved more dissolved lignocellulose, which is indicated by the highest decrease of organic material in the treated samples. To increase the acid concentration, it increases also the disintegration of lignocellulosic material. This is because with the increase of acid (H₂SO₄) concentration, enables separation of organic connections in walls of lignine, enabling easier attacking hemicellulose and cellulose. We were focused more on the acidic and alkaline pretreatment and on the development of experiments, analysis of raw materials, taking samples before and after appropriate pretreatment. Surveillance and identification of changes occurring during pretreatment processes has been conducted for a certain period of time and the important conclusion has been taken.

This work was based on the pretreatment of lingo-cellulosic wastes from agro – forestry organic wastes with samples being taken from stations of different sources. Between many of recommended and explained methods for pretreatment of the organic biomass we selected as the most effective, the way of acidic waste pretreatment and another scenario applying the alkaline method prior to the biodegradation through anaerobic bio-digestion for energy profit. For bio-methane profit process has been performed in a series of the experiments. From the various experiments we realized the great importance of the pre-treatment process for the biogas production. Alkaline pretreatment (with NaOH) brought about a decay of lignin structure of biomass and increase access of enzymes in hemicellulose and cellulose. This method was more effective than acidic treatment due to the fact that was achieved more dissolved lignocellulose, which is indicated by the highest decrease of organic material in the trea...

The research was carried out to extract bio oil from rice straw at different parameters. The major problem in production of bio-oil is its increase in density with the passage of time. The reason for such phenomenon is the cross-linking of lignin which was bound to bio-oil after pyrolysis. The aim of this work was to reduce the lignin content in rice straw and study the effects of decreased lignin content in bio-oil. Additionally enzymatic saccharification of rice straw was also conducted after pre-treatment to estimate optimum conditions for bio-oil production. The independent variables for the optimization of enzymatic saccharification were, time (24, 48, 72 hours), Enzymatic loading ratio (5:10, 10:10, 15:10), substrate concentration (4, 5, 6% w/v) were taken into account. Designed experiments were conducted randomly to find the effect of these variables on reducing sugar, lignin and ash. The analysis of variance for each sample was calculated. The reducing sugar increased with increase in time and enzyme loading ratio while lignin content increased with increase in substrate concentration 48.1 to 51.1% w/w and 9.1 to 12.1 w/w. Optimum value of levels of independent variables obtained by compromise optimization of the responses were; 64.8 h time, 15:10 enzyme loading ratio and 4.62 substrate concentrations.

The global waste management market is worth nearly half a trillion dollars. It faces a dramatic overhaul as technological advancements transform intelligent waste technologies into a thriving and expanding billion-dollar business opportunity. This massive industry experiences the impact of rapid demographic growth, along with increased urbanisation and industrial revolution, which have exacerbated the current environmental problems and the potential for generating sophisticated waste that exceeds the available waste management capacity. In between are knowledge-intensive companies known as solution providers who develop, market, and deploy technologies, processes, or sustainable practices to combat waste problems. In particular, the waste management market is being influenced by major trends, including technological innovation, increased awareness about anthropogenic impacts on the environment, and depleted natural resources.
The impact of digital transformation is significant. Over the last few years, innovation has produced new contenders in high-tech startups offering innovative waste management software such as advanced analytics, artificial intelligence, big data, digital twinning, IoT, and blockchain solutions to meet the growing demand. In addition to the value of waste management software companies being founded or acquired, existing waste management companies are increasingly choosing to collaborate with technology companies, and many of these tech titans are now looking to become waste management players in their own right to improve regulation, transparency, and monitoring of our waste. AI is a tool with many algorithms that can process massive datasets, correlate, and make decisions without human involvement. Therefore, AI could be a powerful tool in waste management. This innovation is ongoing in disparate areas, from e-waste to intelligent bins to monitor and optimise food waste disposal. The text aims to explore the rise of AI in waste management and address critical questions, from benefits to barriers.

This work was based on the pretreatment of lingo-cellulosic wastes from agro – forestry organic wastes with samples being taken from stations of different sources. Between many of recommended and explained methods for pretreatment of the organic biomass we selected as the most effective, the way of acidic waste pretreatment and another scenario applying the alkaline method prior to the biodegradation through anaerobic bio-digestion for energy profit. For bio-methane profit process has been performed in a series of the experiments. From the various experiments we realized the great importance of the pre-treatment process for the biogas production. Alkaline pretreatment (with NaOH) brought about a decay of lignin structure of biomass and increase access of enzymes in hemicellulose and cellulose. This method was more effective than acidic treatment due to the fact that was achieved more dissolved lignocellulose, which is indicated by the highest decrease of organic material in the trea...

Semiconductor-based metal oxide gas detector of five mixed from zinc chloride Z and tin chloride S salts Z:S ratio 0, 25, 50, 75 and 100% were fabricated on glass substrate by a spray pyrolysis technique. With thickness were about 0.2 ±0.05 µm using water soluble as precursors at a glass substrate temperature 500 ºC±5, 0.05 M, and their gas sensing properties toward CH 4 , LPG and H 2 S gas at different concentration (10, 100, 1000 ppm) in air were investigated at room temperature which related with the petroleum refining industry. Furthermore structural and morphology properties were scrutinize. Results shows that the mixing ratio affect the composition of formative oxides were (ZnO, Zn 2 SnO 4 , Zn 2 SnO 4 +ZnSnO 3 , ZnSnO 3 , SnO 2) ratios mentioned in the above respectively, and related with the sensitivity of the reduction tested gases, best sensitivity was for H 2 S gas, have sensitivity about 80.61% and a response time of 10 seconds for the binary oxides and 89.57% and a response time of (5-2) seconds for the mixed ternary oxides.

The globe is looking for fuels other than petroleum-derived ones to lessen its reliance on non-renewable resources. Nowadays, ethanol made from maize grain (starch) and sugar cane (sucrose) is the most widely used renewable fuel. Since the availability of these raw materials is anticipated to reach a limit soon, lignocellulosic biomass is viewed as a promising feedstock for ethanol supplies in the future. But the creation of commercial processes that use biomass is hampered by both financial and technical issues. Innovations in technology are underway to
enable the economical transformation of biomass into chemicals and fuels. Some of these technologies are robust and efficient fermentative
microorganisms, extremely effective cellulases and hemicellulases and inexpensive thermochemical treatments. Commercialization now has greater promise due to the numerous advancements made in the last few years. By creating bioresearch energy and utilizing wastes to make bioethanol, the technique will assist combat the challenges posed by the depletion of fossil fuels and maintain a clean environment. An excellent, environmentally beneficial substitute for non-renewable fuels is bioethanol, which is made from garbage. Greenhouse gas emissions from using conventional gasoline are decreased when a percentage of bioethanol is added. Furthermore, current automobiles operate
flawlessly on bioethanol blends without requiring any engine modifications, contributing to energy savings and a cleaner environment. Hence, bioethanol is a potential alternative energy source in future as there is a strong need for sustainable energy sources to decrease reliance on foreign petroleum oil.

Oil palm plantations in Malaysia generate more than 36 million tones of pruned and felled oil palm fronds (OPF) and are generally considered as waste. The composition of monosaccharide in oil palm frond can be extracted using hydrothermal treatment for useful applications. The objectives of this study were to quantify the yield of monosaccharides at various reaction conditions; temperature 170 °C to 200 °C, pressure from 500 psi to 800 psi, reaction time from 5 to 15 min using subcritical water extraction and to determine the composition of oil palm frond hemicelluloses at optimum condition. The monosaccharides composition of oil palm frond hemicellulose were analysed using High Performance Liquid Chromatography (HPLC). The highest yield of monosaccharides can be extracted from OPF at temperature of 190 C, pressure of 600 psi and 10 min of contact time which is xylose the most abundant composition (11.79 %) followed with arabinose (2.82 %), glucose (0.61 %) and mannose (0.66 %).

This paper presents the process design and assessment of a sugarcane-based ethanol production system that combines the usage of both mass and heat integration (pinch analysis) strategies to enhance the process efficiency and renewability performance. Three configurations were analyzed: (i) Base case: traditional ethanol production (1G); (ii) mass-integrated (1G2G); and (iii) mass and heat-integrated system (1G2G-HI). The overall assessment of these systems was based on complementary approaches such as mass and mass-heat integration, energy and exergy analysis, exergy-based greenhouse gas (GHG) emissions, and renewability exergy criteria. The performances of the three cases were assessed through five key performance indicators (KIPs) divided into two groups: one is related to process performance, namely, energy efficiency, exergy efficiency, and average unitary exergy cost (AUEC), and the other one is associated to environmental performance i.e., exergy-based CO 2-equation emissions and renewability exergy index. Results showed a higher exergy efficiency of 50% and the lowest AUEC of all the systems (1.61 kJ/kJ) for 1G2G-HI. Furthermore, the destroyed exergy in 1G2G-HI was lower by 7% and 9% in comparison to the 1G and 1G2G cases, respectively. Regarding the exergy-based GHG emissions and renewability performance (λ index), the 1G2G-HI case presented the lowest impacts in terms of the CO 2-equivalent emissions (94.10 gCO 2-eq/MJ products), while λ index was found to be environmentally unfavorable (λ = 0.77). However, λ index became favorable (λ > 1) when the useful exergy of the byproducts was considered.

This study examines the practicable method of lignin delignification and fractionation from Oil Palm Empty Fruit Bunches (OPEFB) to produce high purity products. A review on the current literature progress in this field indicated two development phases that involves several early studies on lignin delignification and lignin product purification and the later phase provides initial attempts to improve lignin recovery efficiency and overcome technical barriers for obtaining high purity lignin. It is found that there are significant gaps in understanding to achieve efficient removal of lignin, good recovery of lignin from high purity products and the removal of silica residuals on OPEFB surfaces. Accordingly, the high technical barriers to achieve high-purity lignin products are identified, including the need for an improved method to delignify and fractionate lignin for the purpose of producing a higher purity product. It can be concluded that fractions of lignin may be segregated and isolated by using the ultrafiltration method based on molecule mass and recovery to a higher purity product with over 98wt.%. High purity applications of OPEFB lignin, such as the propylene stabilizer and chemical sunscreen products, can therefore be produced. Accordingly, this review also provided an opportunity to further develop product applications towards anti ultraviolet, antioxidant and antibacterial functions.

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In this research the activated carbon pretreatments for reed hemicellulose liquor produced in a MILOX process were studied. The remaining sugar fraction was utilised as a raw material for lactic acid fermentation. Earlier results from birch hemicellulose experiments were used for comparison. Pretreated reed hemicellulose liquor can be used as a substrate for lactic acid fermentation by Lactobacillus pentosus. Nearly complete conversion was achieved in 48 h, and the product contained 33 g/1 lactic acid and 17 g/1 acetic acid.

Wood are one of the most important raw material source for forest products industry. Due to technological developments, researchers in the area of wood chemistry have been showing increased interest in the benefits of utilization wood based materials alone or together as an alternative lignocellulosic fiber sources for forest products industry. However, utilization of woody matrials more efficiently and conservation natural resources have been paid special attention. For that reason, it should be carefully consider and beneficial to understanding chemical structure of those woody materials. Many new approaches and techniques have been developed for better understanding of wood chemical sturucture.

Although second generation biofuel technology is a sustainable route for bioethanol production it is not currently a robust technology because of certain hindrances viz., unavailability of potential enzyme resources, low efficiency of enzymes and restricted availability of potent enzymes that work under harsh conditions in industrial processes. Therefore, bioprospecting of extremophilic microorganisms using metagenomics is a promising alternative to discover novel microbes and enzymes with efficient tolerance to unfavourable conditions and thus could revolutionize the energy sector. Metagenomics a recent field in "omics" technology enables the genomic study of uncultured microorganisms with the goal of better understanding microbial dynamics. Metagenomics in conjunction with NextGen Sequencing technology facilitates the sequencing of microbial DNA directly from environmental samples and has expanded, and transformed our knowledge of the microbial world. However, filtering the meaningful information from the millions of genomic sequences offers a serious challenge to bioinformaticians. The current review holds the opinion tool 'knowhow' to unravel the secrets of nature while expediting the bio-industrial world. We also discuss the novel biocatalytic agents discovered through metagenomics and how bioengineering plays a pivotal role to enhance their efficiency.

Empty fruit bunch (EFB), one of the wastes from palm oil production, can be utilized into fuels and chemicals. The aim of this paper is to find the optimum capacity to produce xylitol from EFB. The optimum capacity was found by simultaneously considering its profitability, hazard potential and environmental performances. The process was developed and simulated using Aspen Plus to analyze its technical challenges and economic performances, covering net present values, internal rate of returns and payback period. On the other hand, hazard identification and ranking (HIRA) was used to evaluate its safety performances, while Simapro V.8.5.2 was used to assess the environmental impact via a life cycle assessment (LCA). The results show that the high consumption of steam in chemical hydrogenation causes the main contribution of Global warming potential (GWP) by 62%. This acid pre-treatment is also considered the most toxic part of the process while the hydrogenation of xylitol is the most...

h i g h l i g h t s Composition of PS is directly influenced by the mill feed composition. Corrugated recycle PS proved efficient as substrate for ethanol production. Optimized process resulted in ethanol concentration and yield of 45.5 g/L and 78.2%. High solid loading SSF is affected by PS water holding capacity and viscosity.

Due to the potential exhausting and increasing price of petroleum together with environmental issues caused by the combustion of fossil fuels, the search for alternative fuels has gained much attention. In this study, the combustion, engine performance and emission of characteristics of biodiesel produced from cyanobacteria (blue green algae) will be evaluated. Biodiesel sample used in this research was produced using transesterification processes. 5ml of biodiesel was collected from Department of microbiology department, University of Maiduguri to determine its combustion activities (high heating value, pour and cloud point, flash point and refractive index), engine performance (brake specific fuel consumption, brake thermal energy and brake specific energy consumption) and emission characteristics using biodiesel blend of 95%. All the properties analyzed were within the regulatory limits stipulated for conventional diesel as per ASTM specifications. Biodiesel blended fuels can significantly reduce the emissions of harmful pollutants other than NOx and CO2. Blended biodiesel also improves performance of engine where brake thermal heat (BTE) and brake specific fuel consumption (BSFC) values are reduced significantly.

The impacts of introducing a cellulase-cocktail treatment system before an acid hydrolysis process for isolating cellulose nanocrystals (CNCs) from a cellulose-based model feedstock was investigated. It was found that for a given weight of feedstock, the enzyme-mediated approach improved CNC yield (8-86 wt%) from acid hydrolysis. Another important finding was that significant recovery of fermentable sugars (20-60 wt%), which would otherwise have entered the acid waste stream, is achievable with this method. These findings indicate the potential of enzymatically mediated acid hydrolysis processes for the co-production of fermentable sugars, thus providing additional revenue, and for improvement of the acid hydrolysis efficiency, thus offsetting CNC production costs.

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Recently, the industrial focus has shifted to renewable raw materials due to the exhaustion and rising pressures about environmental and political issues. Lignocellulosic biowaste can be derived from a range of sources, such as animal manure, forestry waste, and agricultural waste, and it can be transformed into lactic acid through a biochemical process. There are 942.63 million cattle in the world and annually generate 3.7 billion tons of manure, which could be used to produce lactic acid. The economic viability of a lactic acid plant from cow manure has not yet been determined and is, thus, considered in this study. Using the modeling program Aspen Plus data and other sources, as well as collecting all economic inputs, the feasibility analysis of a lactic acid plant handling cow manure is assessed in this paper. Three scenarios are calculated to check the feasibility depending on the plant size: scenario I handles 1,579,328 t·year−1, scenario II handles 789,664 t·year−1, and scena...

Circular economy aims to create a system that allows an optimal reuse of products and materials. In this context, the contribution provided by the valorization of residual biomass is fundamental for the production of renewable biological resources and their conversion into new added-value products. Indeed, according to an appropriate planning hierarchy, agricultural and agro-food co-products, byproducts and wastes should be primarily employed to re-balance soil fertility, then valorized as new secondary raw materials used in the same agricultural sector or in different industrial chains (e.g., cosmetics, nutraceuticals, etc.). Only at the end of this process, they could be finally conveyed to energy production through cogeneration. In this paper, the different residues generated by the wine production chain have been considered with reference to the Basilicata region (Southern Italy). These biomasses have been quantitatively evaluated and qualitatively classified, in order to find the most rational and convenient solution for their valorization from a technical, economic and environmental point of view. From the spatial analysis elaborated by implementing a Geographic Information System, some thematic maps have been obtained. These maps have allowed to highlight the areas with the highest concentration of residues. In this way, possible strategies for their management and valorization may be formulated, even with the support of an Internet of Things network system, aimed to allow a constant monitoring of their life cycle.

Olive tree pruning is an abundant and renewable lignocellulosic residue, which is generally burned in the fields, causing economic costs and environmental problems. This lignocellulosic residue can be considered a suitable raw material for the production of a wide range of byproducts in a biorefinery context due to its high content of potentially fermentable carbohydrates. To take advantage of its sugar content, pretreatment is necessary to enhance the accessibility of the enzymes to the cellulosic fraction. The aim of this work is to obtain sugars contained in olive tree pruning as a substrate for the production of bioethanol by fermentation. Specifically, the production of fermentable sugars by sequential pretreatment with sulfuric acid and sodium hydroxide is studied. A two-factor rotatable composite central design temperature and catalyst concentration (H2SO4 and NaOH) has been generated, and response surface methodology has been used to discuss and optimize the responses. This ...

The biorefinery concept is attracting scientific and policy attention as a promising option for enhancing the benefits of agri-food biomass along with a reduction of the environmental impact. Obtaining bioproducts based on proteins from agri-food residues could help to diversify the revenue stream in a biorefinery. In fact, the extracted proteins can be applied as such or in the form of hydrolyzates due to their nutritional, bioactive and techno-functional properties. In this context, the present review summarizes, exemplifies and discusses conventional extraction methods and current trends to extract proteins from residues of the harvesting, post-harvesting and/or processing of important crops worldwide. Moreover, those extraction methods just integrated in a biorefinery scheme are also described. In conclusion, a plethora of methods exits but only some of them have been applied in biorefinery designs, mostly at laboratory scale. Their economic and technical feasibility at large scale requires further study.

A mangrove microbial community was analyzed at the gene and protein levels using metagenomic and proteomic methods with the green macroalgae Enteromorpha prolifera as the substrate. Total DNA was sequenced on the Illumina HiSeq 2000 PE-100 platform. Twodimensional gel electrophoresis in combination with liquid chromatography tandem mass spectrometry was used for proteomic analysis. The metagenomic data revealed that the orders Pseudomonadales, Rhizobiales, and Sphingomonadales were the most prevalent in the mangrove microbial community. By monitoring changes at the functional level, proteomic analyses detected ATP synthase and transporter proteins, which were expressed mainly by members of the phyla Proteobacteria and Bacteroidetes. Members of the phylum Proteobacteria expressed a high number of sugar transporters and demonstrated specialized and efficient digestion of various glycans. A few glycoside hydrolases were detected in members of the phylum Firmicutes, which appeared to be the main cellulose-degrading bacteria. This is the first report of multiple "omics" analysis of E. prolifera degradation. These results support the fact that key enzymes of glycoside hydrolase family were expressed in large quantities, indicating the high metabolic activity of the community.

Simultaneous Saccharification, Filtration and Fermentation (SSFF) was developed for lignocellulosic ethanol production. In SSFF, pretreated lignocellulosic material is enzymatically hydrolyzed in a reactor, while the suspension is continuously pumped through a cross-flow membrane. The retentate goes back to the hydrolysis vessel, while a clear sugar-rich filtrate continuously perfuses through the fermentation vessel before it is pumped back to the hydrolysis vessel. The capacity and life span of the cross-flow filter module was examined for four weeks using enzymatically hydrolyzed slurry, initially with 14.4% suspended solids, without clogging or fouling. An ethanol yield of 85.0% of the theoretical yield was obtained in SSFF and a flocculating strain of Saccharomyces cerevisiae was successfully reused for 5 cultivations of SSFF.

The present study describes a novel method in which petha wastewater (PWW) and rice straw (RS) were pretreated symbiotically to improve the quality of both wastes. This pretreatment helped in lignocellulosic degradation of RS, which can easily undergo anaerobic digestion (AD) for biofuel production. pH and alkalinity of PWW was reduced within limits after pretreatment and amount of soluble sugars of RS also increased significantly. Hence we can kill two birds with one stone i.e. solve disposal problem of highly alkaline PWW and RS simultaneously. Saccharification of RS took place which can then be easily biodegradable anaerobically. Percent increase in cellulose was 9.62% whereas percent decrease in hemicellulose and lignin were 7.23% and 8.88% respectively with respect to untreated RS. pH of PWW was reduced from 12 to 6.4 and calcium carbonate alkalinity was completely reduced to null value from initial value of 2400 mg/L. Structural changes like roughness and porosity are shown in SEM images for both untreated and PWW pretreated RS.

Highlights  Preliminary design of pretreatments and SSF stages for producing ethanol from sugarcane is addressed.  A MILP model based on fixed time and size factors is proposed.  Parametric analysis on the SSF processing time is carried out.  Different production scenarios and economic results are analyzed.

Biofuels as renewable resources are one of the options to meet the challenges of fossil fuel resource depletion and atmospheric pollution. Several studies have focused on the technical, economic, and environmental footprint of biofuels, particularly bioethanol production. However, there has been little effort to incorporate the environmental, health, and safety (EHS) hazards in an inclusive sustainability assessment of bioethanol production alternatives. This study focuses on these sustainability aspects for bioethanol production by employing the EHS and the inherent safety index (ISI) methods. The multicriteria assessment also includes the cumulative energy demand as a widely used lifecycle impact assessment indicator. Sugarcane, corn, and corn stover are considered as biomass resources, and the typical process conditions are used for the base case evaluation. Sensitivity analysis is used to investigate the impact of process conditions, composition of feed, and method settings on the final outcome. The results indicate that both the ISI and the EHS methods present similar overall rankings with sugarcane-derived and corn stover-derived processes as the most and the least hazardous, respectively. However, dissimilarities occur in the evaluation of the process sections, highlighting different hazardous aspects. Finally, including the lifecycle impact assessment in a bicriteria assessment indicates the sugarcane-derived process as clearly superior followed by the corn-derived and the corn stover-derived processes.

Processing of woody lignocellulosic biomass, under heating in combination with ionic liquids (ILs) was studied in order to obtain simple (fermentable) sugars. Due to the new environmental challenges, finding greener ways to produce platform chemicals and/or bio-fuels has become a popular research area. Various industrial, pilot or laboratory scale technologies for the depolymerization or fractionation of lignocellulosic polysaccharides to monomers are known. One of the new, interesting, methods is to utilize ILs in biomass pre-treatment procedures with an aim to bypass other pre-treatment methods. Furthermore, in order even to initiate studies whether ILs can contribute to catalytic depolymerization, there has to be a robust way to analyze the IL-treated lignocellulosics. This is a major issue since woody samples that contain any salts such as ILs can indeed be quite challenging from the analytic point of view. The applied capillary electrophoresis was found to be an excellent analytical method providing substantial improvements compared to the earlier used chromatographic methods. In this work it was demonstrated that application of ILs, at elevated temperatures, contributes to hydrolysis and depolymerization of lignocellulose. The effect is time and temperature dependent: in harsh conditions sugars degrade but too low processing temperatures or short treatment times result in no meaningful effect. The formation of the degradation products of the monosaccharides is a good indicator of the harshness of the applied chemical conditions. Evidently, furfural and 5-(hydroxymethyl)furfural formed in rather short treatment times.

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This work was based on the pretreatment of lingo-cellulosic wastes from agroforestry organic wastes with samples being taken from stations of different sources. Between many of recommended and explained methods for pretreatment of the organic biomass we selected as the most effective, the way of acidic waste pretreatment and another scenario applying the alkaline method prior to the biodegradation through anaerobic bio-digestion for energy profit. For bio-methane profit process has been performed in a series of the experiments. From the various experiments we realized the great importance of the pre-treatment process for the biogas production. Alkaline pretreatment (with NaOH) brought about a decay of lignin structure of biomass and increase access of enzymes in hemicellulose and cellulose. This method was more effective than acidic treatment due to the fact that was achieved more dissolved lignocellulose, which is indicated by the highest decrease of organic material in the treated samples. To increase the acid concentration, it increases also the disintegration of lignocellulosic material. This is because with the increase of acid (H₂SO₄) concentration, enables separation of organic connections in walls of lignine, enabling easier attacking hemicellulose and cellulose. We were focused more on the acidic and alkaline pretreatment and on the development of experiments, analysis of raw materials, taking samples before and after appropriate pretreatment. Surveillance and identification of changes occurring during pretreatment processes has been conducted for a certain period of time and the important conclusion has been taken.

At present, the world is confronted with the twin crises of fossil fuel depletion and environmental degradation. This has made the search for alternative and renewable sources of energy inevitable. Today, examples of such efforts are seen in the production of biofuels from wastes of organic origin, often known as Lignocellulosic Biomass. Lignocellulosic wastes are generated during the industrial processing of agricultural products. These wastes are generated in large amounts throughout the year, and are the most abundant renewable resources on earth. Due to their large availability and composition rich in compounds they could be used in other processes, there is a great interest on the reuse of these wastes, both from economical and environmental viewpoints. This paper present a concise overview of lignocelluloses, their chemical composition, economical and biotechnological potentials in bio-ethanol production with special emphasis on the choice of lignocellulosic substrates, pretre...

Cocoa pod husks are a type of biomass that is still poorly explored. This work was carried out as part of the optimization of the delignification process for this residue with potassium hydroxide, to maximize the reducing sugars content. Screening for potentially influencing factors showed that the biomass to solvent ratio and the temperature had the greatest effect on the delignification process. Optimization of these factors using a composite central plan revealed that the quadratic model was the most suitable for predicting the rate of delignification. The predicted R² (0.815) was in good agreement with the adjusted R² (0.906). The correlation coefficient (R2 = 0.945) between the predicted and experimental results confirmed the fit of the model. The optimal conditions were a biomass to solvent ratio of 9.14% and a temperature of 128 °C, which resulted in a maximum degree of delignification of 93.9%, with 80% of the solids recovered. This study found that the removal of extractabl...

Producing sugar from lignocellulosic biomass is a promising resilient food solution to counter the near-total global failure of food production due to the agricultural collapse that would likely follow an abrupt sunlight reduction catastrophe such as a nuclear winter, a supervolcanic eruption, or a large asteroid or comet impact. This study examines how quickly edible sugar production could be ramped up globally by repurposing pulp and paper mills, sugarcane biorefineries, corn biorefineries, and breweries for lignocellulosic sugar production. A sub-unit component comparison to the NREL 2017 Biochemical Sugar Model indicates that 84%, 65%, 37%, and 39% of ISBL unit components are present, respectively. Fast construction methods were studied to analyze how this and other industrial foods could be rapidly leveraged in a catastrophe.

During the last few decades, lignocellulosic biomass for biofuel production has attracted worldwide attention due to its relative abundance, renewable nature, and availability as a low cost substrate. Generally, lignocellulosic biomass is composed of cellulose, hemicellulose, lignin, and other carbohydrates [1,2]. Especially, cellulose and hemicellulose, the main components of lignocellulosic biomass, have been studied in their capacity to produce fermentable sugars that can then be converted to bioethanol. The chemical composition of cellulose is very simple with b-1,4-glycosidic bonds. However, no single enzyme is able to degrade crystalline cellulose. The bioconversion of cellulose to fermentable glucose requires at least three enzymes for synergistic action: endoglucanases (EC 3.2.1.4) which act randomly on soluble and insoluble cellulose chains, exoglucanases (cellobiohydrolases; EC 3.2.1.91) which liberate cellobiose from the reducing and nonreducing ends of cellulose chains, and b-glucosidases (EC 3.2.1.21) which liberate glucose from cellobiose [3-5]. These enzymes are produced by various fungi including Trichoderma, Aspergillus, and Penicillium sp. Most strains belonging to the Trichoderma and Aspergillus cannot secrete complete cellulolytic and hemicellulolytic enzymes. Trichoderma is well known for its high production of cellulase and Aspergillus is prominent in producing xylanase [6,7]. Penicillium is an efficient producer of cellulase and xylanase and produces relatively higher b-glucosidase activity than Trichoderma. Therefore, Penicillium reduces the feedback inhibition of cellobiose on cellobiohydrolase [8-10]. Penicillium brasilianum among various Penicillium sp. is not well known and their maximum specific growth rate is significantly higher compared to the other strains [11]. An optimization process has been used to enhance the productivity in various research fields which will provide a possible method for the economic and efficient production. Especially, statistical method such as Plackett-Burman design (PBD) and response surface methodology (RSM) may be employed for optimization study. RSM provides an alternative methodology to optimize a process by considering the mutual interactions among the variables and to give an estimate of the combined effect of these variables [12]. In this study, mutant P. brasilianum KUEB15 was utilized for cellulase production and the optimization of culture media was investigated for the enhancement of cellulase production.