Application of thermophilic temperatures,low hydraulic retention times and high recycling of de-gassed effluent for higher biohydrogen production

This study investigated the external operational factors that would reduce the thermodynamic constrains preventing the simultaneous achievement of high hydrogen productivities (HPs) and hydrogen yields (HYs) in the bioreactor. At hydraulic retention time (HRT) of 1, the maximum HPs and HYs achieved was 35 L H₂/h and 3.91 mol H₂/mol glucose, respectively. At this stage, the bacterial granules occupied approximately 75% of the bioreactor and consisted of the settled biomass density of 40.6 g/L (settled granule bed height = 13.8 cm). The formation of bacterial granules improved the bioreactor performance and resulted in higher substrate conversion efficiency (95%), nutrient influent (7.5 L/h) and de-gassed effluent recycle rates (3.5 L/min). In conclusion, this study demonstrated that high nutrient influent and high de-gassed effluent recycle rates reduced the thermodynamic constrains preventing the achievement of higher H₂ productivities in the bioreactor system.     

Thermo-rheological analysis of various chain extended recycled poly(ethylene terephthalate)

Three chain extenders, pyromellitic dianhydride (PMDA), ethylene carbonate (EC), and a polymeric-epoxide, were investigated for improving recycled p(ethylene terephthalate) (r-PET) properties with melt extrusion. The amount of additives and processing temperatures were also varied to check for melt degradation. Small amplitude oscillatory shear experiments were performed to probe rheological changes with different chain extenders. Capillary rheometry with haul-off was also performed to measure extensional viscosity and melt strength. Higher loadings of the chain extenders were found to improve properties of r-PET. These chain extenders definitely increased melt viscosities when incorporated at the higher level of the ranges examined, matching that of virgin PET. EC addition resulted in high shear thinning of the polymer. Epoxy and PMDA added to r-PET produced products with the same extensional viscosity as v-PET. Haul-off experiments demonstrate superior performance by epoxy-modified r-PET compared to v-PET.     

废旧磷酸铁锂锂离子电池正极的回收

采用磷酸(H3PO4)溶液对废旧LiFePO4电池正极片在低温热解得到的粉末材料进行浸出,以铁盐溶液作为补充铁源,合成电池级磷酸铁(FePO4),并将滤液pH值调到8.0以上,得到工业级磷酸锂(Li3PO4)。通过SEM、XRD和电化学性能测试,研究热处理温度、反应原料配比与溶液pH值对回收产物形貌和性能的影响。将正极片在350℃下热解2 h分离得到的粉末加入到85℃的H3PO4溶液中,在n(P)∶n(Fe)为1.3∶1.0的条件下,制备的FePO4结晶度好。制备的电池在2.5~4.0 V充放电,0.2 C和2.0 C放电比容量最高分别达到160.2 mAh/g和150.3 mAh/g。以Li3PO4方式回收滤液中的锂元素,当p H值为10时,回收率达到90%,Li3PO4纯度在99.4%以上。     

A simple method for purification of bromelain in a thermosensitive triblock copolymer-based protection system and recycling of phase components

In the work, we chose stem bromelain as a model to investigate the storage and purification of bromelain from pineapple peel. Extraction of bromelain from pineapple peel using a two-stage aqueous two-phase extraction system composed of a thermoseparating copolymer EOPOEO and K₂HPO₄. Bromelain predominantly partitioned to the EOPOEO-rich phase and then re-extract to the top dilute phase. The recovery of enzyme activity (68.6%) and purification factor (6.53) were determined under optimum conditions. The EOPOEO-rich phase and salt were recycled, and the recovery of enzyme activity could reach up to 60%. This method has been proved to obtain highly purified and stable bromelain.     

论循环经济的理论体系及产业结构的完善

完善循环经济的理论基础和产业结构是循环经济理论研究和实践的迫切需要。本文从8个方面对此进行了论述:循环经济是可持续发展原则指导下的新经济发展模式;循环经济的哲学基础:崇拜-征服-协调的哲学理论;循环经济的地球物质循环基础:非平衡热力学理论;循环经济资源评价体系的更新:自然资源价值论对循环经济形成内在机制的影响;循环经济对于经济发展目标的诠释:从生命演化规律到人类文明的转型;循环经济的宏观、微观、中观科技支撑体系:地球系统科学、资源综合应用技术及环境影响评价;当前循环经济产业环节的缺失对于循环经济发展的不利影响;循环经济产业组织结构重建的迫切要求:建立以生产为目标的第零产业和以分解为目标的第四产业。     

法国洛代夫铀水冶厂工艺流程的改进——碱性浸出剂再生及溶液返回法

洛代夫铀水冶厂原采用加压碱法浸出和直接沉淀的流程从矿石中回收铀。本文叙述了作者为改进洛代夫铀水冶厂的生产，提出的碱性浸出剂再生和溶液循环的新方法。在不必更新和增加设备的条件下，改进了该厂的生产工艺流程，提高了经济效益，降低了生产成本。该方法已直接用于洛代夫厂的生产中，并为该厂节省至少每年1400万法郎的操作费用。     

加快江西矿产资源产业循环经济发展的对策与建议

文章简要分析了江西省矿产资源开发利用的现状和存在的主要问题。认为要促进江西矿产资源产业和国民经济可持续发展,就必须大力发展循环经济,并根据实际情况提出了相应的对策建议。     

循环经济对资源型城市发展的导向研究

本文讨论了循环经济的内涵，指出中国资源型城市发展循环经济的强然性和紧迫性。探析了循环经济理论对资源型城市的产业重构、非线性和非物质发展的导向作用，对资源型城市实现可持续发展起到重要作用。     

国内金属矿产资源供应力的现状与对策浅析

在国际金属矿产储量不断增加的背景下，我国矿产资源供应力不足，对外依存度提高。由于浅部资源枯竭和生态环境破坏严重，危机矿山现象突出，接替资源供给不足。我国的矿石冶炼能力〉采选能力〉新增探明接替资源量，从而危机矿山成为限制资源供应力的主要瓶颈。在政府高度重视与相应政策出台情况下，基础理论与找矿实践相结合，在主要矿种的隐伏矿体预测方面取得重要突破，而采选冶新流程的开发利用提高了矿石的利用率，同时大力发展循环经济成为缓解金属矿产资源危机的重要方向与有效措施。以科学技术进步和管理制度创新为核心进行开源节流，是增强国内金属矿产资源供应力，实现可持续发展的有力保障。