响应面法优化Fenton预处理干法腈纶废水

采用Fenton法预处理难降解干法腈纶废水,选取H2O2用量、Fe2+用量、初始pH和反应温度4个因素为变量,COD去除率为响应值进行中心组合设计。利用响应面法对实验结果进行分析,建立了以COD去除率为响应值的二次多项式模型并进行了显著性检验,分析了各因素单独及交互作用对COD去除率的影响,确定了最佳反应条件,并考察了最佳条件下处理前后废水可生化性和毒性变化。结果表明,所选取的4个因素影响COD去除率的主次顺序依次为:H2O2用量、Fe2+用量、初始pH和反应温度;在H2O2浓度为90.0 mmol/L、Fe2+浓度为23.9 mmol/L、初始pH值为3.4、温度为38.5℃的最佳条件下,COD去除率为53.8%,与模型预测值51.9%吻合度较高,偏差仅为3.66%;最佳条件下处理后废水可生化性显著提高,生物毒性明显降低,适宜于后续的生化处理。     

环境工艺方法论研究——归纳演绎法

归纳和演绎是两种不同的推理和认识现实的科学方法。一般地讲,演绎是由一般到特殊的推理,归纳是由特殊到一般的推理,在认识过程中二者是相互联系、相互补充的,是个别与一般的矛盾统一。本文论述了归纳演绎法的定义,在环境工艺中的应用成果及其所依据的哲学原理。     

O3/H2O2工艺降解1,2,4-三氯苯的优化设计

考察用不同的氧化剂降解1,2,4-三氯苯（TCB）,3种不同方法对TCB的去除效果存在较大差别,其处理效果依次为：H2O2〈O3〈O3/H2O2。采用响应面法优化O3/H2O2工艺降解TCB的条件。结果表明,TCB初始浓度和H2O2投加量对TCB去除效果影响较大。TCB的降解符合准一级反应动力学规律,最佳降解条件为TCB初始浓度0.3 mg/L,pH=8.13,H2O2投加量0.40 mmol/L,O3转化率75%。在此条件下,TCB的平均去除率为91.5%,与预测值93.1%吻合度较高。     

The Environmental sustainability of mining in Australia: key mega-trends and looming constraints

At first ‘sustainable mining’ could be perceived as a paradox—minerals are widely held to be finite resources with rising consumption causing pressure on known resources. The true sustainability of mineral resources, however, is a much more complex picture and involves exploration, technology, economics, social and environmental issues, and advancing scientific knowledge—predicting future sustainability is therefore not a simple task. This paper presents the results from a landmark study on historical trends in Australian mining, including ore milled, ore grades, open cut versus underground mining, overburden/waste rock and economic resources. When complete data sets are compiled for specific metals, particular issues stand out with respect to sustainability—technological breakthroughs (e.g. flotation, carbon-in-pulp), new discoveries (e.g. uranium or U), price changes (e.g. Au, boom/bust cycles), social issues (e.g. strikes), etc. All of these issues are of prime importance in moving towards a semi-quantitative sustainability model of mineral resources and the mining industry. For the future, critical issues will continue to be declining ore grades (also ore quality and impurities), increased waste rock and associated liabilities, known economic resources, potential breakthrough technologies, and broader environmental constraints (e.g. carbon costs, water). For this latter area, many companies now report annually on sustainability performance—facilitating analysis of environmental sustainability with respect to production performance. By linking these two commonly disparate aspects—mining production and environmental/sustainability data—it becomes possible to better understand environmental sustainability and predict future constraints such as water requirements, greenhouse emissions, energy and reagent inputs, and the like. This paper will therefore present a range of fundamental data and issues which help towards quantifying the resource and environmental sustainability of mining—with critical implications for the mining industry and society as a whole.     

A SWOT analysis of environmental management practices in Greek Mining and Mineral Industry

Over the last two decades, mining and mineral exploration companies have adopted various environmental management practices in response to society’s pressure for better environmental protection. The literature highlights a number of benefits and challenges for companies adopting environmental management practices with the Greek Mining and Mineral Industry (GMMI) facing similar issues. In order to analyze the challenges faced by the GMMI, a Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis was conducted, which examined the strengths, weaknesses, opportunities and threats faced by the industry when adopting environmental management practices. The analysis prescribes policy recommendations both for the government and industry which, if adopted, could facilitate improved environmental performance.     

铜绿微囊藻生长条件优化模拟研究

采用Plackett Burman实验设计与响应曲面法(RSM)相结合,研究了环境因子对铜绿微囊藻生长的影响。首先采用Plackett-Burman设计对影响藻细胞生长的环境因子进行筛选,结果表明:温度、NaNO3、K2HPO4、Ferric.Citrate对铜绿微囊藻的生长有重要影响,各因子影响值大小为E温度EK2HPO4ENaNO3EFerric.Citrate。在此基础上,用Box-Behnken设计对铜绿微囊藻的生长条件进一步优化,通过对藻细胞最大现存量与各考察因子之间的输入响应关系进行分析,结果表明:铜绿微囊藻的最佳生长条件是:温度为29℃,NaNO3为1.059 mmol/L,K2HPO4为0.057 mmol/L,Ferric.Citrate为0.024mmol/L,此时藻细胞的最大现存量为10.8293×105cells/mL。     

Influence of the operation conditions on CO2 capture by CaO-derived sorbents prepared from synthetic CaCO3

In this work, a statistical experimental design is performed in order to prepare CaCO₃ materials for use as CaO-based CO₂ sorbent precursors. The influence of different operational parameters such as synthesis temperature (ST), stirring rate (SR) and surfactant percent (SP) on CO₂ capture is studied by applying Response Surface Methodology (RSM). The samples were characterized using different analytical techniques including X-ray diffraction, N₂ adsorption isotherm analysis and Scanning Electron Microscopy–X-ray Energy Dispersive Spectroscopy (SEM-EDX). CO₂ capture capacity was determined by means of a thermogravimetric analyzer which recorded the mass uptake of the samples when these were exposed to a gas stream containing diluted (15%) CO₂. The statistical approach used in this work provides a rapid way of predicting and optimizing the main preparation variables of CaO-derived sorbents for CO₂ sorption. The results obtained clearly indicate that four parameters statistically influence CO₂ uptake: SR, the square of SR, its interaction with SP and the square of SP.     

微生物絮凝剂去除废水中Cd（Ⅱ）的CCD优化及絮凝机制

应用CCD（中心复合设计）法研究了微生物絮凝剂去除废水中Cd（Ⅱ）的最佳条件组合,并根据傅里叶变换红外光谱与环境扫描电镜分析讨论了絮凝机制。CCD设计以Cd（Ⅱ）去除率为响应值,优化Cd（Ⅱ）初始浓度、MBFGA1投加量、溶液初始pH和反应时间4种因素。方差分析显示,模型F值为11.71,P〈0.0001,相关系数R=0.9154,拟合模型极显著,Cd（Ⅱ）初始浓度、pH和反应时间为显著性因素。在最优化条件下：Cd（Ⅱ）初始浓度23.60 mg/L,MBFGA1投加量27.74 mg/L,pH为9.5,反应时间15.97 min,检测实验Cd（Ⅱ）去除率高于99.5%。傅里叶变换红外光谱图表明,絮凝剂分子上羧基、羟基、磷酸基等官能团参与了絮凝过程,并形成了氢键。结合环境扫描电镜图分析得出,MBFGA1的絮凝机制包括化学反应、吸附架桥、氢键和范德华力结合等作用。     

The problem of disposing of plaster waste from building sites: problem structuring based on value focus thinking methodology

Plaster is a material which is widely used in Brazil on construction sites. However, its use in recent years has been limited by a legal resolution on the environment introduced in Brazil. One of the regions most affected by these restrictions is the Northeast where the strategic importance of plaster for the region is apparent from the extensive economic development, centered on the gypsum pole of Araripe in the state of Pernambuco. This problem has involved many interested parties, among whom are plaster producers, plastering companies, builders, unions (for plaster workers, and construction workers), Town Halls, and so forth. Therefore, there is a need to structure the problem with a view to obtaining a better understanding of the problem given the lack of information on the real decision problem. To reach this objective, value focus thinking (VFT), a methodology that addresses how values can be used to improve the decision making process, was applied and the problem was structured. Thus, it was possible for the parties involved to clarify their objectives, and specify more precisely the consequences and constraints for the decision problem. In addition, each party involved could get a better understanding of their own wishes. In conclusion, the VFT methodology application enables the parties involved to make more consistent decisions, and therefore to ensure that plaster will continue to be used in the construction industry.     

Methodology to determine regional water demand for instream flow and its application in the Yellow River Basin

Introduction Instream flow is a generic and widely used term that refers to the water required to protect the structure and function of aquatic ecosystems at some agreed level. Other terms that are sometimes used include “environmental flow” (Arthington…