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161.
中共中央提出了“建设资源节约型、环境友好型社会”的号召。本文通过城市水资源循环利用和给排水规划意义及现状、水循环利用及给排水规划的体会,提出了一些水资源循环利用的理念和措施,希望可以用于城市建设发展。 相似文献
162.
Structural study of a lead (II) organic complex – a key precursor in a green recovery route for spent lead‐acid battery paste
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163.
Debabrata Pradhan Sandeep Panda 《Mineral Processing and Extractive Metallurgy Review》2018,39(3):167-180
The by-products of zinc refineries are used as the primary mineral resources for the commercial production of indium. The discarded LCDs containing adequate amount of indium is rather worth as its secondary resources compared to the by-products of zinc refineries. Mining and recycling rates of indium, respectively from minerals and waste LCDs are in progress to meet its huge demand. Recycling of the LCDs has been dominating over mining, as presently 480t of indium are produced annually from mining, however, that of 650t annually from recycling. Different aspects of the extractive metallurgy of indium are summarized in this review paper. 相似文献
164.
页岩气作为新兴、绿色、清洁能源,近年来在全球范围内得到越来越多的关注。从目前国内外页岩气开发情况来看,除开发工艺技术难度大以外,其开发过程中的水污染防控和工业废水的处理也是影响页岩气产业发展的当务之急。如何实现经济高效处理页岩气污水和实现水循环利用,对页岩气的长远发展和当地环境保护有着举足轻重的意义。结合中国石化涪陵页岩气田环境保护,特别是水污染防控工作实践,从页岩气开采工艺过程出发,对水污染防控措施、污水处理工艺和污水的减量循环利用进行了探讨和研究。 相似文献
165.
Marwa M. Ibrahim 《中国化学工程学报》2021,40(12):225-236
To preserve the environment for civilization, we should remove the pollutants like toxic dyes by friendly and cost efficacious method. In this study, the effect of surfactants or mixed surfactants on physicochemical, optical and adsorption properties of ternary mixed oxide CeO2-ZrO2-Al2O3 (CZA) are investigated. The ternary mixed oxide CZA was prepared by surfactants or mixed surfactants assisted ultrasonic co-precipitation method. The physicochemical and optical properties are estimated by different techniques like XRD, TEM, EDX, FTIR, SBET and UV–Vis/DR. The CZAT and CZAC have hybrid shapes and high surface area. The adsorption properties of ternary mixed oxides adsorbents were characterized by sono-removing anionic dyes such as Congo red (CR) and Remazol red RB-133 (RR). The different factors like contact time, different dye concentrations and temperatures also studied. The kinetics and isotherms applications showed that, the adsorption process was followed pseudo second order kinetics and the Freundlich isotherm model. Also, the adsorption is spontaneous and endothermic process through the thermodynamic study. Finally, the results showed that the ternary mixed oxide nano-adsorbent (CeO2-ZrO2-Al2O3) is promising and functional materials for anionic dye sweep from wastewater. 相似文献
166.
Morteza Davarpanah Tahereh Rohani-Bastami 《Chemical Engineering Communications》2016,203(9):1179-1188
Polystyrene-divinylbenzene copolymer (PsDVB) was covalently functionalized with monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine (TEA) by a simple method. The functionalized sorbents were characterized in terms of functionality and morphology, and used for the removal of p-toluic acid (p-TA) from aqueous solution. It was found that DEA-PsDVB has higher adsorption capacity than MEA- and TEA-PsDVB due to more accessible nitro and hydroxyl groups on its surface. Further investigation on the adsorptive properties of DEA-PsDVB indicated that the maximum uptake of p-TA occurred at the optimum pH of 5.3. The kinetics data was successfully represented by the pseudo-first-order model, and the behavior of the adsorption isotherms followed the Freundlich model well. Thermodynamic studies showed that the adsorption of p-TA onto DEA-PsDVB was an endothermic and spontaneous process along with the positive change in entropy. The regeneration of DEA-PsDVB was performed with 0.1 M NaOH solution, and results showed that 99% of the initial capacity was conserved after eight successive adsorption/regeneration cycles. 相似文献
167.
168.
E. J. Martínez-Conesa M. J. Salar-García A. P. De Los Ríos F. J. Hernández-Fernández L. J. Lozano 《Chemical Engineering Communications》2017,204(1):97-104
Although modeling is regarded as a useful tool to understand the performance of microbial fuel cells (MFCs), the number of MFC models remains very low compared with the number of experimental works available in the literature. Moreover, there are very few MFC modeling attempts dealing with the use of wastewater as fuel in these devices, which is essential for the practical implementation of MFCs since the potential of this technology lies in the two-fold benefit of wastewater treatment and bioenergy generation. In this work, a four-factor three-level Box–Behnken design was developed to model the electrochemical power generation in two-chamber MFCs using wastewater as fuel. The optimum values of temperature, external resistance, feed concentration and anodic pH that maximized power output were investigated. Optimum conditions were found at T = 35°C and R = 1 kΩ, corresponding to a maximum power density of 0.88 W·m?3, while feed concentration and pH did not show statistical significance in the ranges studied. Thus, a Box–Behnken design-based model as empirical approach could provide an effective tool for the optimization study of MFC systems. 相似文献
169.
《International Journal of Hydrogen Energy》2022,47(34):15464-15479
Microbial electrolysis cells (MECs) are a new bio-electrochemical method for converting organic matter to hydrogen gas (H2). Palm oil mill effluent (POME) is hazardous wastewater that is mostly formed during the crude oil extraction process in the palm oil industry. In the present study, POME was used in the MEC system for hydrogen generation as a feasible treatment technology. To enhance biohydrogen generation from POME in the MEC, an empirical model was generated using response surface methodology (RSM). A central composite design (CCD) was utilized to perform twenty experimental runs of MEC given three important variables, namely incubation temperature, initial pH, and influent dilution rate. Experimental results from CCD showed that an average value of 1.16 m3 H2/m3 d for maximum hydrogen production rate (HPR) was produced. A second-order polynomial model was adjusted to the experimental results from CCD. The regression model showed that the quadratic term of all variables tested had a highly significant effect (P < 0.01) on maximum HPR as a defined response. The analysis of the empirical model revealed that the optimal conditions for maximum HPR were incubation temperature, initial pH, and influent dilution rate of 30.23 °C, 6.63, and 50.71%, respectively. Generated regression model predicted a maximum HPR of 1.1659 m3 H2/m3 d could be generated under optimum conditions. Confirmation experimentation was conducted in the optimal conditions determined. Experimental results of the validation test showed that a maximum HPR of 1.1747 m3 H2/m3 d was produced. 相似文献