Technoeconomic analysis of continuous biodrying process in conjunction with gasification process at pulp and paper mills

In the biorefinery context, thermochemical processes have attracted a significant attention in recent years. Such processes generally consist of three main steps: pretreatment, thermochemical treatment, and post-treatment. In these developing processes, drying and feeding of biomass feedstock remain a significant and costly challenge. The moisture content of biomass feedstock must be decreased to an economic level at pretreatment step otherwise it has to have a detrimental effect on the process efficiency and quality of products. This work addresses the drying of biomass feedstock using novel but practical technology, called biodrying. It is a green technology that offers an opportunity for biomass drying without using an external heat source or fossil fuels, since drying energy is generated through exothermic microbial activity in the biomass that enhances the drying rate. This paper focuses on technoeconomic assessment of continuous biodrying technology integrated to gasification-based biorefinery and investigates the conditions that make such novel technology viable in conjunction with gasification process. Fixed capital investment and operating cost of different biodrying scenarios were estimated as M$4.3–21 and M$0.85/y–3.6/y, respectively, and potential benefits (sludge landfilling cost, energy savings, and carbon credit) from integration of the continuous biodrying system in gasification process implemented in pulp and paper mill were calculated, and ultimately economic performances of the scenarios were assessed. Furthermore, the viable biodrying conditions were specified as 4-day residence time and the major viability risk was found to be bound moisture of biomass.     

A Biorefinery Concept for Energy Intensive Industries Focusing on Microalgae and Anaerobic Digestion

The biorefinery concept will be important to the energy industry as it allows a multi-process, multi-product biomass based industry. Continued increases in the prices of fossil fuels, the uncertainty of their availability and the environmental impacts of their extraction are favouring the implementation of sustainable energy production. This article provides a literature review of algal biomass utilisation, process utilisation, technological and economic factors when applying the biorefinery concept to energy intensive industries （whether retro-fitting or new buildings）. This report focuses on opportunities in Finland for innovation, process integration and the development of supply chains whilst using flue gases as a feedstock for the microalgae. Currently, most research is on thermal combustion technologies. Microalgae provide an excellent opportunity to reduce carbon dioxide emissions by mitigation in such industries as pulp and paper. However, a beneficial driver would be feed-in tariffs or green trade certificates but are not necessary for the potential success within the industry. Reducing the overall economic costs with process integration and efficient technologies is beneficial for commercialisation of microalgae biorefineries. Microalgae biorefinery with a high efficiency could help improve the cost effectiveness of microalgae derived biofuels. The remaining algae after harvesting could be used for biogas production, which could be upgraded for vehicle fuel or the production of heat and power. An economically viable microalgae biorefinery with appropriate technologies and integrated for optimum efficiency is therefore possible.     

小球藻作为食品利用的国外报道研究进展

普通小球藻和蛋白核小球藻作为新食品资源,是国际上广泛研究、养殖、应用的2种小球藻属绿藻,富含蛋白质、维生素等营养物质,可提纯或转化出大量的生物活性化合物,在食品等产业具有广泛的应用潜力。该文基于近10年来普通小球藻和蛋白核小球藻在育种、养殖、收获、下游处理、食品研发方面的国外报道,就小球藻营养成分与功效、食品领域应用及存在问题、传统和新兴微藻细胞破碎技术、产业发展策略与趋势4个方面进行综述,重点介绍国内小球藻产业不破壁藻粉消化性差的现状及工业化细胞破碎技术的优缺点,基于微藻生物精炼的理念提出了小球藻产业发展的近、中、远期发展策略,以期为国内高校院所的研发及小球藻养殖加工企业的技术信息提供参考。     

Chitosan Derivatives as Important Biorefinery Intermediates. Quaternary Tetraalkylammonium Chitosan Derivatives Utilized in Anion Exchange Chromatography for Perchlorate Removal

There has recently been great interest in the valorization of biomass waste in the context of the biorefinery. The biopolymer chitosan, derived from chitin, is present in large quantities of crustacean waste. This biomass can be converted into value-added products with applications in energy, fuel, chemicals and materials manufacturing. The many reported applications of this polymer can be attributed to its unique properties, such as biocompatibility, chemical versatility, biodegradability and low toxicity. Cost effective water filters which decontaminate water by removal of specific impurities and microbes are in great demand. To address this need, the development of ion exchange resins using environmentally friendly, renewable materials such as biopolymers as solid supports was evaluated. The identification and remediation of perchlorate contaminated water using an easy, inexpensive method has come under the spotlight recently. Similarly, the use of a low cost perchlorate selective solid phase extraction (SPE) cartridge that can be rapidly employed in the field is desirable. Chitosan based SPE coupled with colorimetric analytical methods showed promise as a renewable anion exchange support for perchlorate analysis or removal. The polymers displayed perchlorate retention comparable to the commercial standard whereby the quaternized iron loaded polymer TMC-Fe(III) displayed the best activity.     

Implementation of a Forest Biomass-Based Biofuel Industry： A Canadian Experience

The forest biomass is an abundant renewable resource from which biofuels can be derived. In the Kraft process, the cellulose is extracted from the wood to form the paper pulp while the other organic components, primarily hemicelluloses and lignin, are burnt to produce steam. It is possible to divert part of the hemicelluloses or lignin to produce fuels on site, a mode of operation referred to as the integrated forest biorefinery. Hemicelluloses can be hydrolysed into sugars which in turn are converted into ethanol or butanol, while lignin can be extracted from a residual process stream, the black liquor, by acid precipitation, de-ionized, dried and directly used as a fuel or further processed into value added chemicals. Biorefinery processes have been proposed and analysed by simulation on Aspen Plus. Intensive integration of thermal energy, water and material systems is of paramount importance to the sustainability of the global site; the increased energy load on the utility systems could cause rising dependency of the global site on fossil fuels. To avoid this consequence, a new original energy efficiency analysis and enhancement methodology has been developed and validated on actual Canadian Kraft mills before being applied to the integrated biorefinery and, has produced remarkable results far superior to the current engineering practice. This has led to the concept of the GIFBR （green integrated forest biorefinery）, i.e., an industrial site with zero fossil fuel consumption and reduced GHG （greenhouse gases） emissions vs. the Kraft process and biorefinery plant alone. The GIFBR incorporates a woody biomass gasifier producing syngas as a fuel for the integrated biorefinery and for steam production or sale. It can also include a CHP （combined heat and power） unit driven by steam made available by liberated production capacity from the installed power plant.     

制浆造纸厂实行生物炼制的可行性

生物炼制是解决石化资源紧缺的新途径,而制浆造纸厂是生物炼制技术最容易实现产业化的平台。文章综述了制浆造纸厂中半纤维素、木质素、松节油、妥尔油等废弃生物质进行生物炼制的可行性及存在的问题,并对发展前景作了展望。     

Comparative lipidomic analysis of S. cerevisiae cells during industrial bioethanol fermentation

Variations in the composition and level of phospholipids (PLs) in yeast cells during industrial ethanol fermentation processes were analyzed. A comparative lipidomic method was used to investigate the changes in total cellular PLs during continuous and fed-batch/batch processes. The phospholipid metabolism in yeast changed during both processes, mainly due to the presence of long-chain poly unsaturated fatty acids (PUFA) that contained phosphatidyglycerol (PG), phosphatidylethanolamine (PE) and phosphatidylserine (PS). The complexity of the media affected the growth of the yeast and the membrane composition. Yeast incorporated lots of exogenous saturated and PUFAs from the feedstock during the fermentations. During the continuous fermentation, there was an increase in PLs with shorter chains as the fermentation progressed and early in process there were more long-chains. During the fed-batch/batch process, the PG species increased as the fermentation progressed. This is probably due to an inositol deficiency in the earlier part of the fermentation.     

生物质制备乙酰丙酸酯类转化路径的研究进展

乙酰丙酸酯类是比较重要的一类平台化合物,具有广泛的应用。本文首先介绍了乙酰丙酸酯类的生物炼制途径,然后综述了目前国内外制备乙酰丙酸酯类的研究现状和最新进展。乙酰丙酸酯类的主要制备方法包括乙酰丙酸合成法、糠醇转化法以及生物质醇解法,并对3种方法的优劣进行说明,指出今后乙酰丙酸酯类的制备方法将以生物质直接醇解法为主。建议着力建立生物质直接醇解法反应过程中的热力学性质等相关数据,并加强与此相关的交叉学科的研究,以构建生物质醇解法制备乙酰丙酸酯类的理论基础。     

Techno-Economic Assessment of a Microalgae Biorefinery

A preliminary techno-economic assessment of a microalgae biorefinery plant is reported, with pulsed electric field treatment (PEF) hydrothermal liquefaction as core technology. The results indicate that standalone production of microalgae biofuel would lead to an annual loss of 2.615 M€. PEF treatment could improve this scenario by bringing the microalgae biofuel to a competitive level (0.78 € kg⁻¹). Assuming that microalgae biofuel would be sold at the price of crude oil (0.44 € kg⁻¹), the minimum price of the amino-acid based product should be 7.56 € L⁻¹ for positive capital returns.