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81.
82.
Bioconversion of sludge from the primary clarifier of a sulphite pulping operation to ethanol offers a number of advantages over conventional disposal options. The amount of material which must be disposed of is reduced while, at the same time, salable and environmentally friendly fuel-ethanol is produced. In this study, primary clarifier sludge (PCS) was shown to be hydrolysed to produce fermentable sugars at a rate proportional to enzyme loading. Initial (1 hour) hydrolysis rates as high as 12.6 g reducing sugar/L · h were observed at an initial enzyme loading of 10 filter paper units (FPU)/g. Hydrolysis was inhibited by spent sulphite liquor (SSL), an inhibition which could be completely overcome by fermenting the SSL to remove sugars. Surfactants were found to only marginally improve the production of sugars. To reduce the deleterious effects of end product inhibition, single stage simultaneous hydrolysis and fermentation (SHF) was carried out using cellulase enzymes and Saccharomyces cerevisiae. 相似文献
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85.
本文以处理辣根废水为例,介绍一种新的水处理方法-膜分离活性污泥法,并阐述了膜分离活性污泥法如何解决污泥膨胀问题以及传统活性污泥法所不具有的特性。 相似文献
86.
The concentration of uniformly distributed particles in a fluid changes with time in the direction of gravitational or centrifugal
force to form a concentration gradient. The change in the concentration is an outcome of velocity variation of particles in
a fluid. A modified equation for terminal velocity, v
m of particles in polymerizing-fluid under centrifugal force is proposed to estimate the changes in the volume fraction of
particles in the graded composites. The proposed equation introduces the effect of cure kinetics of polymer and its effect
on particle movement in the model that was based on the modified Stoke’s law, considering the parameters related to particle
hindrance, centrifugal force, particle dimensions, viscosity variation etc. The model predictions of concentration changes
at the different locations of samples were compared with calcium carbonate filled polysulphide-modified-epoxy graded composites
prepared by centrifugal casting.. The effect of particle size, delayed curing rate of matrix were explored. The simulated
results are in good agreement with those of experiments. 相似文献
87.
城市污泥的处理及污泥制活性炭的研究现状 总被引:1,自引:0,他引:1
介绍了国内外一些污泥处理减量化技术及研究进展,分析了几种常用的污泥处置方法及存在的问题.用城市污水厂污泥制备活性炭,可以用于污水处理,去除有毒有害物质,具有良好的环境效益和社会效益. 相似文献
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89.
Steel microfiber reinforcement was previously found to be successful in mitigating alkali silica reaction in concrete, an expansive phenomenon. The use of steel microfibers to mitigate rebar corrosion, another expansive reaction, was investigated. Mortar specimens with and without steel microfiber reinforcement were exposed to a corrosive environment. All specimens were prepared with water/cement ratios of both 0.40 and 0.55, cured for 28 days, and then submerged in aerated 3.5% NaCl solution. The corrosion behavior of the specimens was monitored via electrochemical measurements. Three types of electrochemical tests were performed: corrosion potential measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy. Chloride concentration measurements and microscopic analysis were performed as well. The polarization curves, Tafel, and polarization resistance measurements indicate that the steel rebar in the microfiber-reinforced mortars are more resistant to corrosion than the rebar in the control mortars, despite higher chloride concentrations. Furthermore, the steel microfiber-reinforced cement based materials have a lower electrolytic resistance. This is not indicative of a higher corrosion rate, which would be the case if it had been observed in standard mortar specimens. 相似文献
90.
针对当前火力发电厂中监控系统存在多系统、多网络协议并存的情况,研究与设计了基于OPC的钠离子浓度监测系统。系统采用LM3S8962为核心处理器,16位高精度无偏差模数转换器AD7705作为AD采样模块,采用Modbus TCP为网络通信协议,设计一个基于Modbus TCP协议的OPC服务器,真正实现钠离子浓度监测系统的智能化、网络化和规范化。 相似文献