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31.
Zhi‐Long Ye Min Lu Yan Zheng Ya‐Hong Li Wei‐Min Cai 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(11):1541-1550
BACKGROUND: Food waste generally has a high starch content and is rich in nutritional compounds, including lipids and proteins. It therefore represents a potential renewable resource. In this study, dining‐hall food waste was used as a substrate for lactic acid production, and response surface methodology was employed to optimise the fermentation conditions. RESULTS: Lactic acid biosynthesis was significantly affected by the interaction of protease and temperature. Protease, temperature and CaCO3 had significant linear effects on lactic acid production, while α‐amylase and yeast extract had insignificant effects. The optimal conditions were found to be an α‐amylase activity of 13.86 U g?1 dried food waste, a protease activity of 2.12 U g?1 dried food waste, a temperature of 29.31 °C and a CaCO3 concentration of 62.67 g L?1, which resulted in a maximum lactic acid concentration of 98.51 g L?1 (88.75% yield). An increase in inoculum size would be appropriate for accelerating the depletion of initial soluble carbohydrate to enhance the efficiency of α‐amylase in dining‐hall food waste fermentation. CONCLUSION: A suitable regression model for lactic acid production was developed based on the experimental results. Dining‐hall food waste was found to be a good substrate for lactic acid fermentation with high product yield and without nutrient supplementation. Copyright © 2008 Society of Chemical Industry 相似文献
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33.
Use of zeolite-rich rocks and waste materials for the production of structural lightweight concretes
R. de Gennaro A. Langella M. D'Amore M. Dondi A. Colella P. Cappelletti M. de' Gennaro 《Applied Clay Science》2008,41(1-2):61-72
This paper aims at testing the use of mixtures constituted by natural zeolitized products and SiC-bearing industrial wastes (sludge deriving from polishing of porcelain stoneware tiles, hereafter DPM) for the production of lightweight expanded aggregates as constituents of structural and/or thermo-insulating lightweight concretes. Two commercial products have been used as zeolite natural source: Cab70 (Yellow facies of Campanian Ignimbrite) and IZclino (Turkish clinoptilolite-rich epiclastite). Different amounts of a calcareous material (Pozzano limestones — hereafter CP) from the Sorrento peninsula (Naples — Italy) were also added to a Cab70–DPM mixture. All raw materials were characterized by means of mineralogical (XRPD) and chemical (XRF) analyses. All the products and mixtures were tested from a technological point of view by means of fusibility and firing tests in order to evaluate the expanding properties. It was evidenced that the expansion of the mixture was deeply depending on the occurrence of SiC in the industrial waste. The addition of CP (10 wt.%) to the mixtures accounts for an even increased expansion, though this is accompanied by a worsening of the mechanical features of the material.These results along with literature data allowed to select 3 mixtures (70% Cab70–30% DPM, 70% IZclino–30% DPM, 60% Cab70–30% DPM–10% CP) and each of them was used for the preparation of 5 l of lightweight aggregates afterward employed for the manufacture of lightweight concretes. It was remarked that natural zeolitized materials mixed with DPM (30 wt.%) can provide lightweight aggregates with densities ranging between 0.8 and 1.0 g/cm3 suitable for the preparation of structural lightweight concretes. The addition to the mixture of CP (10 wt.%) produces less dense aggregates (0.6–0.7 g/cm3) potentially useful for the manufacture of thermo insulating lightweight concretes. 相似文献
34.
文章概要论述了一种新型民用炸药-含过期火药粉状工业炸药在配方、制造工艺等方面所进行的实验研究。结果表明,该炸药性能良好、制造技术安全可靠,值得推广。 相似文献
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36.
从铅阳极泥中回收铋的火法工艺实践 总被引:4,自引:2,他引:2
主要论述了从铅阳极泥中回收铋的全火法工艺流程改造与实践,并取得了预期的效果。 相似文献
37.
中国第一口超千米深水钻井液技术 总被引:3,自引:1,他引:2
LW3-1-1探井位于中国南海珠江口盆地,作业水深1480m,完钻井深为3843m,地层以大套灰色泥岩和页岩为主,具有强水敏性.要求钻井液具有良好的流变性、润滑性、抑制性,良好的抗盐、抗钙、抗高温和抗低温能力,以及强的天然气水合物抑制能力。该井采用了PFMX钻井液体系,钻井周期为49d,介绍了钻井液工艺及现场应用情况。PFMX体系表现出很多油基钻井液的优点,如好的润滑性、高的钻进速率、膜效应、强的井眼稳定及页岩抑制性,解决了强水敏性地层的井壁稳定等问题,还解决了深水钻井中遇到的挑战,如低的破裂压力梯度、天然气永合物、浅层水流、深水低温等问题,满足了该区块作业需要。 相似文献
38.
Leach characteristics of 137Cs and 60Co radionuclides from both ordinary Portland cement and cement mixed with two different ratios of silica fume and ilmenite have been studied using International Atomic Energy's (IAEA) standard leach method. A mathematical model has been simulated to predict the release rate of each nuclide from cubic geometry waste matrix and the predicted values are discussed in relation to experimentally observed leach rates to confirm the validity of the proposed mechanism in the model. The effect of temperature on the radionuclides leaching rates was also studied and the effective diffusion coefficients were obtained at different temperatures. The net fractional release of the two radionuclides from different waste forms showed a decreasing pattern as 137Cs>60Co, indicating the largest diffusion coefficient for cesium in all waste matrices. 相似文献
39.
The care of the world environment poses many challenges to the proper disposal of mineral wastes. Particulate wastes can be used to modify the properties or lower the cost of polymers. The influence of an iron–silica rich waste on the hardness of an epoxy resin is evaluated in this work. It is shown that the hardness values are polymer dominated for volume fractions of waste lower than 0.30, but for higher volume fractions a useful increase in the hardness numbers can be achieved. The coarser the particles are the more heterogeneous is the microstructure of the composite. Nevertheless, particulate rich layers increase the hardness of the material several times. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2178–2184, 2002 相似文献
40.
印制板蚀刻、微蚀刻废液的再生和铜回收的技术及设备 总被引:8,自引:0,他引:8
传统的印制板蚀刻废液处理方法存在着工艺落后、操作不便、二次污染、效益不高等问题,本工艺采用特殊的萃取电解、吸附电解技术,使蚀刻废液得以再生循环利用,铜得以100%回收,低含铜废水铜得到98%回收,整个系统不产生二次污染,获得的铜为高纯度铜板,在实现污染控制的同时,废液废水得到了资源化利用。 相似文献