以植物油为原料发展我国生物柴油炼油厂的探讨

以生物质资源为原料发展生物炼油厂，是炼油和石化工业实现可持续发展的一条重要途径。在介绍了国外以玉米为原料发展生物炼油厂设想的基础上，根据我国国情，提出了以植物油为原料发展生物柴油炼油厂的设想，分析了国内发展这种生物炼油厂的意义，并讨论了可能出现的一些问题及解决方法。认为在国家政策的激励和支持下，生物炼油厂在我国必将得到快速发展。     

A multiobjective optimization framework for design of integrated biorefineries under uncertainty

A systematic approach for development of a reliable optimization framework to address the optimal design of integrated biorefineries in the face of uncertainty is presented. In the current formulation, a distributed strategy which is composed of different layers including strategic optimization, risk management, detailed mechanistic modeling, and operational level optimization is applied. In the strategic model, a multiobjective stochastic optimization approach is utilized to incorporate the tradeoffs between the cost and the financial risk. Then, Aspen Plus models are built to provide detailed simulation of biorefineries. In the final layer, an evolutionary algorithm is employed to optimize the operating condition. To demonstrate the effectiveness of the framework, a hypothetical case study referring to a multiproduct lignocellulosic biorefinery is utilized. The numerical results reveal the efficacy of the proposed approach; it provides decision makers with a quantitative analysis to determine the optimum capacity plan and operating conditions of the biorefinery. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3208–3222, 2015     

Pyrolysis of Banana and Coffee Residues after Acid Hydrolysis

The use of the residues from renewable feedstock, besides the production of fuels, but also for the generation of other chemicals products, has become a priority. Superior plants have considerable potential as carbohydrate, aryl and fatty acids sources. However, the separation of the main constituents of the samples is necessary for several purposes in the biorefinery concept. The acid hydrolysis and pyrolysis processes are very promising technology, however, some adjustments in the conditions of pyrolysis are needed for different biomasses since carbohydrates were detected （14%-17%） in the residues after the conventional acid hydrolysis of these uncommon biomasses （coffee husk and banana stem and stalk）. On the other hand, it was showed that, by pyrolysis, it is possible to obtain from the solid residue after acid hydrolysis： pyrogenic carbon （charcoal with a yield of 48.5%-52.7%） for agriculture use （biochar） and valuable chemicals in the pyrolysis oil biooil fraction （that accounted by 26.4%-29.0%, free of water）, such as lignin monomers （32.6%-56.4% of the bio-oil） and fatty acids （30%-52.5%）.     

Xylitol production by different yeasts: Kinetic study and biosynthesis from cashew apple bagasse hydrolysate

Xylitol is a polyol with sweetening and anti-cariogenic properties and is highly relevant to the food and pharmaceutical industries. This work evaluates xylitol production by three yeasts (Candida tropicalis, Kluyveromyces marxianus CCA510, and Kluyveromyces marxianus ATCC 36907) from different carbon sources: D-xylose (medium xylose [MX]) and D-xylose plus D-glucose (medium xylose and glucose [MXG]). The potential of xylitol production from hemicellulose hydrolysate of cashew bagasse was evaluated. In MX medium, K. marxianus CCA510 was the strain that produced higher xylitol concentration (17.04 g · L⁻¹). However, K. marxianus ATCC 36907 and C. tropicalis produced 13.22 and 9.54 g · L⁻¹, respectively. On the other hand, in MXG medium, probably due to the presence of glucose as a carbon source, lower xylitol production was observed for all microorganisms: the CCA510 strain produced 13.30 g · L⁻¹ of xylitol, while C. tropicalis and ATCC 36907 produced 11.42 and 0.64 g · L⁻¹, respectively. Additionally, the production of ethanol as a secondary product was also noted. According to the results of the kinetic study, xylitol formation is associated with the growth and consumption of substrate (xylose), which is a typical behaviour of a primary metabolite for the three yeasts. Furthermore, the strain K. marxianus CCA510 was able to produce xylitol from cashew apple bagasse hydrolysate (CABH), evidencing its potential for use in bioprocesses related to biorefinery. In view of the results reported here, it was possible to clarify in detail the kinetics of xylitol production by the yeast strains evaluated, which had the ability to produce xylitol from CABH, providing added value to this agro-industrial residue.     

Sustainable design and synthesis of algae‐based biorefinery for simultaneous hydrocarbon biofuel production and carbon sequestration

The superstructure optimization of algae‐based hydrocarbon biorefinery with sequestration of CO₂ from power plant flue gas is proposed. The major processing steps include carbon capture, algae growth, dewatering, lipid extraction and power generation, and algal biorefinery. We propose a multiobjective mixed‐integer nonlinear programming (MINLP) model that simultaneously maximizes the net present value (NPV) and minimizes the global warming potential (GWP) subject to technology selection constraints, mass balance constraints, energy balance constraints, technoeconomic analysis constraints, and environmental impact constraints. The model simultaneously determines the optimal decisions that include production capacity, size of each processing unit, mass flow rates at each stage of the process, utility consumption, economic, and environmental performances. We propose a two‐stage heuristic solution algorithm to solve the nonconvex MINLP model. Finally, the bicriteria optimization problem is solved with ε‐constraint method, and the resulting Pareto‐optimal curve reveals the trade‐off between the economic and environmental criteria. The results show that for maximum NPV, the optimal process design uses direct flue gas, a tubular photobioreactor for algae growth, a filtration dewatering unit, and a hydroprocessing pathway leading to 47.1 MM gallons of green diesel production per year at $6.33/gal corresponding to GWP of 108.7 kg CO₂‐eq per gallon. © 2013 American Institute of Chemical Engineers AIChE J, 59: 1599–1621, 2013     

Integrated Forest Biorefinery: Value-added Utilization of Dissolved Organics in the Prehydrolysis Liquor of Prehydrolysis Kraft (PHK) Dissolving Pulp Production Process

The concept of integrated forest biorefineries(IFBRs) has gained significant interest.The prehydrolysis kraft(PHK) dissolving pulp production process is a suitable example of IFBR concept for the production of dissolving pulp and utilization of dissolved hemicelluloses,acetic acid,and lignin in the prehydrolysis liquor(PHL).This review paper highlights recent progress related to the recovery and utilization of dissolved organics(e.g.,hemicelluloses,acetic acid,and lignin) in the PHL of the PHK dissolving pulp production process.Integrated multi-step recovery and separation processes have been developed for this purpose to accommodate the complex nature of the PHL.Potential products,including xylan-based compounds,acetic acid,and lignin,are also discussed in detail.     

稀水解液循环回用对玉米秸秆水解液中主要化学组分得率的影响

为实现对水洗玉米秸秆自水解预处理固相物产生的稀水解液（简称稀水解液）中主要化学组分的高效利用,探讨了自水解预处理工艺条件以及将稀水解液回用于玉米秸秆自水解预处理对水解液中主要化学组分得率的影响。结果表明,在液固比10∶1（V/w）、170 ℃保温40 min条件下,水解液中糖类化合物、甲酸、呋喃化合物及酚类化合物等主要化学组分得率均达到最大值。在此工艺参数基础上添加2%乙酸作为自水解处理过程中的催化剂,可进一步提高糖类、弱酸类及呋喃化合物的得率。将稀水解液循环回用于玉米秸秆的自水解预处理过程7次后,水解液中主要化学组分则分别进一步显著（P < 0.05）提高21.0%（糖）、71.0%（甲酸）、44.6%（乙酸）、80.7%（酚类化合物）、102.1%（糠醛）及98.5%（5-羟甲基糠醛）,有效实现了水解液中主要化学组分的富集和增浓。上述研究为玉米秸秆自水解预处理工艺的调整及稀水解液的利用提供理论依据和数据支持。     

Enzymatic Pretreatment with Laccases from Lentinus sajor-caju Induces Structural Modification in Lignin and Enhances the Digestibility of Tropical Forage Grass (Panicum maximum) Grown under Future Climate Conditions

Since laccase acts specifically in lignin, the major contributor to biomass recalcitrance, this biocatalyst represents an important alternative to the pretreatment of lignocellulosic biomass. Therefore, this study investigates the laccase pretreatment and climate change effects on the hydrolytic performance of Panicum maximum. Through a Trop-T-FACE system, P. maximum grew under current (Control (C)) and future climate conditions: elevated temperature (2 °C more than the ambient canopy temperature) combined with elevated atmospheric CO₂ concentration(600 μmol mol⁻¹), name as eT+eC. Pretreatment using a laccase-rich crude extract from Lentinus sajor caju was optimized through statistical strategies, resulting in an increase in the sugar yield of P. maximum biomass (up to 57%) comparing to non-treated biomass and enabling hydrolysis at higher solid loading, achieving up to 26 g L⁻¹. These increments are related to lignin removal (up to 46%) and lignin hydrophilization catalyzed by laccase. Results from SEM, CLSM, FTIR, and GC-MS supported the laccase-catalyzed lignin removal. Moreover, laccase mitigates climate effects, and no significant differences in hydrolytic potential were found between C and eT+eC groups. This study shows that crude laccase pretreatment is a potential and sustainable method for biorefinery solutions and helped establish P. maximum as a promising energy crop.     

葡萄酒泥高价值产物开发及生物炼制研究概况

文章综述了葡萄酒泥中具开发潜力的高价值产物研究,以及可实现酒泥全面利用的生物炼制研究概况,分析了限制中国葡萄酒泥工业化开发利用的原因并提出了建议.