Organic waste derived bioethanol supply chain network: Multiobjective snapshot model with a real-Korea case study.

Bioethanol, a promising biofuel gasoline additive, was recently produced by a new technology using acetic acid derived from organic waste. This study develops a multiobjective mathematical model with two competing minimization objectives: economy and environmental impact. The formulation is based on a mixed integer linear programming approach. The configuration of the organic-waste (OW)-based bioethanol supply chain network is optimized in terms of the number and locations of bioethanol refineries. The flows of acetic acid and bioethanol between the geographical nodes must meet the bioethanol regional demand. The model is validated in three real-scenario case studies with different OW utilization rates (30%, 50%, and 70%) in South Korea in the near future (2030). The multiobjective problem is solved using the ε-constraint method and the selected Pareto solutions balance the trade-off between the economic and environmental objectives. At the "best-choice" solution points, increasing the OW utilization rate from 30% to 70% decreased the total annual cost from 904.2 to 707.3 million $/yr and the total greenhouse emissions from 1087.2 to -15.7 CO2 equiv./yr.

Comparison of polylactic acid biodegradation ability of Brevibacillus brevis and Bacillus amyloliquefaciens and promotion of PLA biodegradation by soytone.

Polylactic acid (PLA), a biodegradable plastic, is used to substitute commercial plastics in various fields such as disposable packaging materials and mulching films. Although the biodegradation of PLA under submerged or composting conditions is accelerated, increasing the biodegradability of PLA under soil burial conditions is still a challenge. This study reviews and compares the PLA biodegradation ability of Bacillus amyloliquefaciens and Brevibacillus brevis, both PLA-degrading bacteria. The biodegradation ability of a single bacteria in non-composting conditions was evaluated. In addition, in terms of biostimulation, PLA biodegradation according to nitrogen sources was compared. As a result, a higher PLA biodegradation ability was found in B. brevis than in B. amyloliquefaciens. Moreover, it was confirmed that the biodegradation of the PLA film was increased by using soytone as a nitrogen source in both bacteria. Controlling the nitrogen source could be a new way to increase the biodegradation of PLA.

Organic-waste-derived butyric acid-to-biodiesel supply-chain network: Strategic planning design using a deterministic snapshot model.

An integrated optimization model for an organic-waste-derived butyric acid-to-butanol supply-chain network (BABSCN) is proposed to minimize the total network cost by simultaneously optimizing both strategic biodiesel production and waste management planning decisions. This model is useful for ensuring effective organic-waste provision for large-scale biodiesel production and waste management. The proposed mixed-integer linear-programming model optimizes the activities ranging from organic-waste preprocessing to butyric acid (BA), transportation of BA to biorefinery, butanol (BuOH) production and mixing with diesel to the distribution of biodiesel. This model is useful for forecasting organic-waste management biodiesel supply chains in South Korea in 2030. The case study results show that a total network cost of $US 3.16/gallon of B3 contains 3% BuOH from organic waste products combined with diesel. The biorefinery-related cost accounts for 98.3% of the total network cost, followed by the organic waste procurement cost (1.1%) and biodiesel distribution cost (0.6%). A scenario-based analysis shows that a 7%-BuOH increase in biodiesel increases the total network cost by 18.8%.

Techno-economic analysis and life cycle assessment of poly (butylene succinate) production using food waste.

In this present study, the production of poly (butylene succinate) (PBS) from food waste was investigated and critical factors were evaluated. The economic feasibility of the process was investigated, as well as the minimum selling price (MSP) of PBS and sensitivity analysis of economic factors based on critical input parameters. 1,4-butanediol price and solvent usage in PBS purification significantly impacted economics during the process. In this process, the MSP of PBS was 3.5 $/kg. The Monte Carlo simulation technique was used to determine the uncertainty in the MSP of PBS. The plant's return on investment (ROI), payback period, internal rate of return (IRR), and net present value (NPV) were 15.79 %, 6.33 years, 16.48 %, and 58,879,000 USD, respectively. The environmental impact factors were evaluated. The results showed the GHG emission from the process was 5.19 kg CO2-eq/kg of PBS which is low than conventional PBS production.

Health and happiness of older Korean women participating in dance activities.

This study aimed to determine the health and happiness of older women participating in dance activities using the phenomenological analysis method. The study used snowball sampling to recruit eight participants among older women participating in a 3-month dance program in Korea, starting from March 2019. Data were collected through in-depth interviews and participatory observations, after which the gathered raw data were codified, systematically arranged, and analysed. The contents were then categorized by topic or content into different categories to derive meaningful interpretations and research results. To enhance the reliability and validity of the analysis, objectivity was ensured by applying appropriate criteria for assessing qualitative research. The analysis determined the participants' motivations for participation, health satisfaction, and happiness. The results conclusively and theoretically confirm the importance of dance-induced feelings of health and happiness among the older women in the study. The results should encourage relevant government agencies and other organizations to put increased effort into enacting policy measures to promote older women's health by revitalizing their participation in dance activities and providing them with long-term recreational interventions.

Enhancing biodegradation of PBAT through bio-stimulation using Pseudozyma jejuensis for effective plastic waste reduction.

Polybutylene adipate-co-terephthalate (PBAT) is a flexible and biodegradable material that finds applications in mulching film and the food packaging industry. In this study, we aimed to address the global plastic waste problem by developing an improved biodegradation system for PBAT. Our focus was on utilizing the biodegradation capabilities of Pseudozyma jejuensis, a microorganism known for its ability to decompose Polycaprolactam (PCL). Through bio-stimulation, we aimed to enhance the growth mechanism of P. jejuensis and optimize PBAT biodegradation. Our results demonstrated significant structural changes in the PBAT film, as revealed by FT-IR analysis. Moreover, FE-SEM imaging exhibited evident surface erosion and pitting, indicating physical alterations due to biodegradation. These findings provide strong evidence for the efficiency of our developed biodegradation system. To fully harness the potential of this system and enable its practical implementation, further research is warranted to optimize and scale up the process. Our work contributes to the ongoing efforts to combat the global plastic waste crisis, offering a valuable solution for the efficient biodegradation of PBAT.

A strategic review on sustainable approaches in municipal solid waste management andenergy recovery: Role of artificial intelligence,economic stability andlife cycle assessment.

The consumption of energy levels has increased in association with economic growth and concurrently increased the energy demand from renewable sources. The need under Sustainable Development Goals (SDG) intends to explore various technological advancements for the utilization of waste to energy. Municipal Solid Waste (MSW) has been reported as constructive feedstock to produce biofuels, biofuel carriers and biochemicals using energy-efficient technologies in risk freeways. The present review contemplates risk assessment and challenges in sorting and transportation of MSW and different aspects of conversion of MSW into energy are critically analysed. The circular bioeconomy of energy production strategies and management of waste are also analysed. The current scenario on MSW and its impacts on the environment are elucidated in conjunction with various policies and amendments equipped for the competent management of MSW in order to fabricate a sustained environment.

Techno-economic analysis of food waste valorization for integrated production of polyhydroxyalkanoates and biofuels.

This study focused on the techno-economic analysis of integrated polyhydroxyalkanoates (PHAs) and biofuels such as biohydrogen, bioethanol, and 2,3-butanediol production from food waste (FW). Based on previous literature studies, the integrated process was developed. The process plan produced 2.01 MT of PHAs, 0.29 MT of biohydrogen, 4.79 MT of bioethanol, and 6.79 MT of 2,3-butanediol per day, from 50 MT of FW. The process plan has a positive net present value of 4.47 M$, a 13.68% return on investment, a payback period of 7.31 yr, and an internal rate of return of 11.95%. Sensitivity analysis was used to examine the economic feasibility. The actual minimum selling price (MSP) of PHAs was 4.83 $/kg, and the lowest achievable MSP with 30% solid loading is 2.41 $/kg. The solid loading in the hydrolysis stage and the price of byproducts have a major impact on the economic factors and MSP of PHAs.

Integrated polylactic acid and biodiesel production from food waste: Process synthesis and economics.

In this study, techno-economic analysis of the sustainable production of polylactic acid (PLA) and biodiesel from Food Waste (FW), with a plant capacity of 50 tons/day, was investigated. In addition, FW of four countries (China, India, Brazil, and the USA) with different compositions of water, protein, lipid and carbohydrate were proposed. Each country has different PLA production rates based on carbohydrate and biodiesel production based on fat. In this study, the FW composition of the USA shows better economic feasibility than other countries. The actual minimum selling price is 6.53 (China), 5.35 (India), 4.75 (Brazil), and 4.29 (US) $/kg. The uncertainty of the MSP was analyzed based on various input limits. The sensitivity analysis was conducted based on biodiesel-selling price, PLA-selling price, income tax, and project lifetime on techno-economic analysis parameters, such as ROI, payback period, IRR and NPV were investigated.

Process evaluation and techno-economic analysis of biodiesel production from marine macroalgae Codium tomentosum.

In the current study, a seaweed Codium tomentosum was used as a source for the production of biodiesel. The maximum oil from marine macroalgae was recovered using ultrasound-assisted pretreatment. The oil yield was found to be maximum at optimal conditions such as 5% biomass wetness, 0.18 mm biomass size, 6:1 extraction solvent: biomass ratio, extraction temperature, and time as 55 °C and 140 min respectively. The extracted oil was transesterified using solidsolid nanocatalyst produced from waste clay doped with Zn. The maximum biodiesel conversion was found to be 90.5% at optimum conditions. The marine macroalgae C. tomentosum was found to be one of the potential sources for biodiesel production. The techno-economic analysis of the overall biodiesel production (20 MT/batch) process was investigated. The plant payback period is 8.59 years with a positive NPV of 1381 M$/yr.

Environmental analysis of bioethanol production strategies from corn stover via enzymatic and nonenzymatic sugar production.

Two different technological process configurations for producing bioethanol from corn stover, namely, enzymatic hydrolysis for sugar production followed by fermentation (P1) and nonenzymatic chemical hydrolysis and subsequent fermentation (P2), were analyzed by a rigorous life cycle assessment. Three environmental impact categories (climate change (CC), fossil depletion (FD), and air pollutant (AP)) were estimated for the both process configurations on a system level. The "best-practice" case with a real scenario of the United States of America indicates that P2 is the most promising strategy from the perspectives of CC, FD, and AP. Considerable savings were achieved by P2: 1.34 kg CO2-eq/gallon of gasoline equivalent (GGE) for CC, 0.12 MJ/GGE for FD, and 0.24-0.94 g particle matters/GGE for AP. The robustness of the environmental impact results was validated by a scenario uncertainty analysis, and its results indicated that the corn stover composition is crucial.

Lifecycle assessment of methanol production from blast furnace gas.

A technological scenario configuration for producing methanol (MeOH) from blast furnace gas (BFG) with natural gas (NG)-based energy generation was evaluated by a rigorous life cycle assessment. The new BFG scenario was compared to a conventional BFG scenario-BFG energy generation with NG-based MeOH production. In all, 18 environmental impact categories were estimated for both technological BFG scenario configurations on a conceptual plant level. The results of a case study in South Korea indicated that the new BFG scenario performs better for 12 environmental impacts (20-97% lower), but fossil resource depletion is worse because NG is used for the displacement of energy generation. The robustness of the environmental impact results for the new BFG scenario was supported by a case study, which highlighted that the primary source for the displacement of energy generation is crucial.

Renewable Butanol Production via Catalytic Routes.

Fluctuating crude oil price and global environmental problems such as global warming and climate change lead to growing demand for the production of renewable chemicals as petrochemical substitutes. Butanol is a nonpolar alcohol that is used in a large variety of consumer products and as an important industrial intermediate. Thus, the production of butanol from renewable resources (e.g., biomass and organic waste) has gained a great deal of attention from researchers. Although typical renewable butanol is produced via a fermentative route (i.e., acetone-butanol-ethanol (ABE) fermentation of biomass-derived sugars), the fermentative butanol production has disadvantages such as a low yield of butanol and the formation of byproducts, such as acetone and ethanol. To avoid the drawbacks, the production of renewable butanol via non-fermentative catalytic routes has been recently proposed. This review is aimed at providing an overview on three different emerging and promising catalytic routes from biomass/organic waste-derived chemicals to butanol. The first route involves the conversion of ethanol into butanol over metal and oxide catalysts. Volatile fatty acid can be a raw chemical for the production of butanol using porous materials and metal catalysts. In addition, biomass-derived syngas can be transformed to butanol on non-noble metal catalysts promoted by alkali metals. The prospect of catalytic renewable butanol production is also discussed.

Recent advances in valorization of organic municipal waste into energy using biorefinery approach, environment and economic analysis.

Researcher's all around works on a copious technique to lessen waste production and superintend the waste management for long-term socio-economic and environmental benefits. Value-added products can be produced from municipal waste by using holistic and integrated approaches. In this review, a detail about the superiority of the different methods like anaerobic digestion, biofuel production, incineration, pyrolysis and gasification were used for the conversion of municipal waste to feedstock for alternate energy and its economic- environmental impacts were consolidated. Most conversion techniques were environmentally friendly to manage municipal waste. The biological process was more economically feasible compare to the thermal process, for the reason thermal process required a large amount of capital investment and energy utilization. In the thermal process, gasification shows low emission, and pyrolysis shows low capital investment and economically feasible compare to other thermal processes. Waste to energy technology significantly reduced the emission and energy demand.

Catalytic production of 1,4-pentanediol from corn stover.

A novel strategy of large-scale 1,4-pentanediol (1,4-PDO) production derived from corn stover is presented based on catalytic conversion experiments. In this strategy, cellulose and hemicellulose of corn stover are catalytically converted to GVL by using corn stover derived GVL asa reaction solvent, and GVL asa reaction intermediate is then upgraded to 1,4-PDO. In the strategy, three possible designs consisting of conversion and separation subsystems are developed in terms of biomass residues as electricity or fuel sources (A: electricity source, B: electricity and fuel sources, and C: fuel source). The economic feasibility of the process designs was demonstrated taking into account the minimum selling price (MSP; US$/kg) of 1,4-PDO with a comparison with the petro-based process. Design C was the best MSP (US$ 1.25/kg) of those assessed because of its higher energy efficiency (69-82%) while meeting lower total annualized costs (4.7-6.5%) than Designs A and B.

Catalytic production of biofuels (butene oligomers) and biochemicals (tetrahydrofurfuryl alcohol) from corn stover.

A strategy is presented that produces liquid hydrocarbon fuels (butene oligomers (BO)) from cellulose (C6) fraction and commodity chemicals (tetrahydrofurfuryl alcohol (THFA)) from hemicellulose (C5) of corn stover based on catalytic conversion technologies using 2-sec-butylphenol (SBP) solvents. This strategy integrates the conversion subsystems based on experimental studies and separation subsystems for recovery of biomass derivatives and SBP solvents. Moreover, a heat exchanger network is designed to reduce total heating requirements to the lowest level, which is satisfied from combustion of biomass residues (lignin and humins). Based on the strategy, this work offers two possible process designs (design A: generating electricity internally vs. design B: purchasing electricity externally), and performs an economic feasibility study for both the designs based on a comparison of the minimum selling price (MSP) of THFA. This strategy with the design B leads to a better MSP of $1.93 per kg THFA.

A catalytic biofuel production strategy involving separate conversion of hemicellulose and cellulose using 2-sec-butylphenol (SBP) and lignin-derived (LD) alkylphenol solvents.

A strategy in which the hemicellulose and cellulose fractions of lignocellulosic biomass are converted separately to jet fuel-range liquid hydrocarbon fuels (butene oligomers) through catalytic processes is developed. Dilute sulfuric acid (SA)-catalyzed pretreatment fractionates the first biomass into cellulose and hemicellulose-derived xylose, and these are then converted separately to levulinic acid (LA) using 2-sec-butylphenol (SBP) and lignin-derived (LD) alkylphenol solvents, respectively. LA is upgraded catalytically to butene oligomers via γ-valerolactone (GVL) and butene intermediates. Separation subsystems are designed to recover the alkylphenol solvents and biomass-derived intermediates (LA and GVL) for combination with the catalytic conversion subsystems of hemicellulose, cellulose, and lignin. In addition, a heat exchanger network (HEN) design is presented to satisfy the energy requirements of the integrated process from combustion of biomass residues (degradation products). Finally, a technoeconomic analysis shows that the proposed process ($3.37/gallon of gasoline) is an economically competitive alternative to current biofuel production approaches.

A lignocellulosic ethanol strategy via nonenzymatic sugar production: process synthesis and analysis.

The work develops a strategy for the production of ethanol from lignocellulosic biomass. In this strategy, the cellulose and hemicellulose fractions are simultaneously converted to sugars using a γ-valerolactone (GVL) solvent containing a dilute acid catalyst. To effectively recover GVL for reuse as solvent and biomass-derived lignin for heat and power generation, separation subsystems, including a novel CO2-based extraction for the separation of sugars from GVL, lignin and humins have been designed. The sugars are co-fermented by yeast to produce ethanol. Furthermore, heat integration to reduce utility requirements is performed. It is shown that this strategy leads to high ethanol yields and the total energy requirements could be satisfied by burning the lignin. The integrated strategy using corn stover feedstock leads to a minimum selling price of $5 per gallon of gasoline equivalent, which suggests that it is a promising alternative to current biofuels production approaches.

Nonenzymatic sugar production from biomass using biomass-derived γ-valerolactone.

Widespread production of biomass-derived fuels and chemicals will require cost-effective processes for breaking down cellulose and hemicellulose into their constituent sugars. Here, we report laboratory-scale production of soluble carbohydrates from corn stover, hardwood, and softwood at high yields (70 to 90%) in a solvent mixture of biomass-derived γ-valerolactone (GVL), water, and dilute acid (0.05 weight percent H2SO4). GVL promotes thermocatalytic saccharification through complete solubilization of the biomass, including the lignin fraction. The carbohydrates can be recovered and concentrated (up to 127 grams per liter) by extraction from GVL into an aqueous phase by addition of NaCl or liquid CO2. This strategy is well suited for catalytic upgrading to furans or fermentative upgrading to ethanol at high titers and near theoretical yield. We estimate through preliminary techno-economic modeling that the overall process could be cost-competitive for ethanol production, with biomass pretreatment followed by enzymatic hydrolysis.