Copper and arsenic substance flow analysis of pyrometallurgical process for copper production

The metabolism of copper and arsenic in a copper pyrometallurgy process was studied through substance flow analysis method.The mass balance accounts and substance flow charts of copper and arsenic were established,indicators including direct recovery,waste recycle ratio,and resource efficiency were used to evaluate the metabolism efficiency of the system.The results showed that,the resource efficiency of copper was 97.58%,the direct recovery of copper in smelting,converting,and refining processes was 91.96%,97.13%and 99.47%,respectively.Meanwhile,for producing 1 t of copper,10 kg of arsenic was carried into the system,with the generation of 1.07 kg of arsenic in flotation tailing,8.50 kg of arsenic in arsenic waste residue,and 0.05 kg of arsenic in waste water.The distribution and transformation behaviors of arsenic in the smelting,converting,and refining processes were also analyzed,and some recommendations for improving copper resource efficiency and pollution control were proposed based on substance flow analysis.

Two Approaches of Substance Flow Analysis—An Inspiration from Fluid Mechanics

That flow is the common feature of substance flow and fluid flow is the viewpoint emphasized in the paper. Some notes on fluid mechanics, including the two approaches of fluid flow description, were given. The concepts of the chain and the chain group of product life cycles, which are essential for understanding the specific features of substance flow, were advanced. Taking the specific feature of substance flow into consideration, on the analogy of the two approaches in fluid mechanics, two approaches of substance flow analysis, i.e. L method and E model, were formulated. Illustrative models of steady and unsteady substance flow were sketched by both methods, and comparison between them was made in general.

A dynamic analysis of environmental losses from anthropogenic lead flow and their accumulation in China

Substance flow analysis was applied to analyzing the lead emissions in 2010. It turns out that in 2010, for every 1 kg of lead consumed, 0.48 kg lead is lost into the environment. The emissions in 2010 were estimated to be 1.89×10^6 t, which were mainly from use （39.20%） and waste management＆recycling （33.13%）. The accumulative lead in 1960-2010 from the anthropogenic flow was estimated and the results show that the total accumulative lead in this period amounted to 19.54×10^6 t, which was equivalent to 14.26 kg and 2.04 g/m^2 at the present population and territory.

Substance flow analysis for an urban drainage system of a representative hypothetical city in China

This paper discusses the use of substance flow analysis （SFA） as a tool to support quantified research on urban drainage systems. Based on the principle of mass balance, a static substance flow model is established to describe and examine the routes and intensities of water, chemical oxygen demand （COD）, total nitrogen （TN） and total phosphorus （TP） for a representative hypothetical city （RH city） in China, which is a devised and scaled city using statistical characteristics of urban circumstances at the national level. It is estimated that the annual flux of water, COD, TN and TP through the urban drainage system in 2010 was 55.1 million m3, 16037.3 t, 1649.5 t and 209.7 t, respectively. The effluent of wastewater treatment plant （WWTP） was identified as the most important pathway for pollutant emissions, which con- tributed approximately 60% of COD, 65% of TN and 50% of TP to receiving water. During the wastewater treatment process, 1.0 million m3, 7042.5 t, 584.2 t and 161.4 t of the four studied substances had been transmitted into sludge, meanwhile 3813.0 t of COD and 394.0 t of TN were converted and emitted to the atmosphere. Compared with the representative hypothetical city of 2000, urban population and the area of urban built districts had expanded by approximately 90% and 80% respectively during the decade, resulting in a more than threefold increase in the input of substances into the urban drainage system. Thanks to the development of urban drainage systems, the total loads of the city were maintained at a similar level.

Vanadium metabolism investigation using substance flow and scenario analysis

Vanadium is a vital strategic resource, and vanadium metabolism is an important part of the national socio-economic system of China. This study conducts accounting and scenario analysis on the life cycle of vanadium metabolism in China. Based on the character- istics of vanadium life cycle and substance flow analysis （SFA） framework, we present a quantitative evaluation of a static anthropogenic vanadium life cycle for the year 2010. Results show that anthropogenic vanadium consumption, stocks, and new domestic scrap are at 98.2, 21.2, and 4.1 kt, respectively; new scrap is usually discarded. The overall utilization ratio of vanadium is 32.2%. A large amount of vanadium is stockpiled into tailings, debris, slags, and other spent solids. A scenario analysis was conducted to analyze the future developmental trend of vanadium metabolism in China based on the SFA frame- work and the qualitative analysis of technology advance- ment and socio-economic development. The baseline year was set as 2010. Several indicators were proposed to simulate different scenarios from 2010 to 2030. The scenario analysis indicates that the next 20 years is a critical period for the vanadium industry in China. This paper discusses relevant policies that contribute to the improvement of sustainable vanadium utilization in China.

Tungsten and arsenic substance flow analysis of a hydrometallurgical process for tungsten extracting from wolframite

In this study,the metabolism of a hydrometallurgical process for tungsten extracting from wolframite was studied through substance flow analysis.The mass balance accounts,substance flow charts of tungsten and arsenic were established to evaluate the metabolism efficiency of the investigated system.The results showed that,the total tungsten resource efficiency of the system was 97.56%,and the tungsten recovery of unit process autoclaved alkali leaching,ion exchange,Mo removing,concentration and crystallization was 98.16%,98.94%,99.71%,99.89%,respectively.Meanwhile,for extracting 1 ton of tungsten into the qualified ammonium paratungstate,10.0414 kg of arsenic was carried into the system,with the generation of 7.2801 kg of arsenic in alkali leaching residue,1.5067 kg of tungsten in arsenic waste residue,and 1.2312 kg of tungsten in Mo residue.Besides,7.9 g of arsenic was discharged into nature environment with waste water,15.5 g of arsenic was entrained into the final APT.The distribution and transformation behaviors of arsenic during production were analyzed through phases change analysis,and some recommendations for improving the resource efficiency of tungsten and pollution control during production were also proposed based on the substance flow analysis in this study.

Carbon flow analysis of China＇s agro-ecosystem from 1980 to 2013： A perspective from substance flow analysis

Research on carbon cycling has attracted attention from both scientists and policy-makers. Based on material flow analysis, this study systematically budgets the carbon inputs, outputs and balance from 1980 to 2013 for China＇s agro-ecosystem and its sub-systems, including agricultural land use, livestock breeding and rural life. The results show that from 1980 to 2013, both the carbon input and output were growing gradually, with the carbon input doubling from 1.6 Pg C/year in 1980 to 3.4 Pg C/year in 2013, while carbon output grew from 2.2 Pg C/year in 1980 to 3.8 Pg C/year in 2013. From 1980 to 2013, the crop production system in China has remained a carbon source, and the agricultural land uses were also almost all carbon sources instead of carbon sinks. As soil carbon stock plays a very important role in deciding the function of China＇s agro-ecosystem as a carbon sink or source, practices that can promote carbon storage and sequestration will be an essential component of low carbon agriculture development in China.

典型锑-金冶炼过程金和铅物质流分析

应用物质流分析锑-金火法冶炼系统。以金、铅为目标元素,建立了基于生产系统的物质平衡表和物质流图,构建了有关系统直接回收率、废物回收率、资源利用效率的评价指标体系。结果表明:系统内金的资源利用效率为91.76%,挥发熔炼、挥吹炉挥吹、还原熔炼和除杂精炼过程金的直收率分别为86.39%、92.27%、98.64%和95.60%。同时,每产出1 t金属锑,会有6.78 kg的铅进入到冶炼系统中。重点分析冶炼过程中有价元素金及有害元素铅在主要单元过程中的分布转化行为。最后,基于物质流分析提出提高资源利用效率和清洁生产的建议。

农业生产消费系统氮损失特征及其不确定性

准确量化活性氮损失是农业生产消费系统氮管理的重要基础。以长江三角洲地区(长三角地区)为研究区,基于物质流分析法研究农业生产消费系统的氮损失特征,采用误差传播方程量化氮损失的不确定性,并采用多元回归分析对其传播机制进行分析。结果表明,2011—2020年,长三角地区农业生产消费系统活性氮损失总量由2011年的(1841.0±150.4)Gg/a上升至2013年的(1874.1±154.2)Gg/a,随后逐年下降至2020年的(1636.4±144.6)Gg/a。作物种植和畜禽养殖子系统是活性氮损失最大的两个源,10年平均占比分别为37.5%和31.0%。10年间,二者的活性氮损失占比均呈下降趋势,而居民消费和废物管理子系统活性氮损失占比均呈上升趋势。大气环境是系统活性氮损失最主要的汇,10年平均占比为52.2%。不确定性方面,系统活性氮损失总量的不确定性为8.1%—8.8%,其中,废物管理子系统和地表水环境活性氮损失分别为不确定性最高的源和汇。由人类活动水平数据和氮流参数引入的系统氮损失的不确定性分别为1.2%—1.3%和8.0%—8.8%,表明后者是氮损失不确定性的主要来源。畜禽养殖子系统和地表水环境损失对系统氮损失总量不确定性的贡献最大,分别为27.4%和50.0%。多元回归分析结果显示,各组分氮损失通量及其不确定性两个因素均显著影响氮损失总量的不确定性,且各组分氮损失通量是影响不确定性传播的主导因素。研究结果可为降低农业生产消费系统氮损失的不确定性提供参考。

Integrating phosphorus management and cropping technology for sustainable maize production

Achieving high maize yields and efficient phosphorus(P)use with limited environmental impacts is one of the greatest challenges in sustainable maize production.Increasing plant density is considered an effective approach for achieving high maize yields.However,the low mobility of P in soils and the scarcity of natural P resources have hindered the development of methods that can simultaneously optimize P use and mitigate the P-related environmental footprint at high plant densities.In this study,meta-analysis and substance flow analysis were conducted to evaluate the effects of different types of mineral P fertilizer on maize yield at varying plant densities and assess the flow of P from rock phosphate mining to P fertilizer use for maize production in China.A significantly higher yield was obtained at higher plant densities than at lower plant densities.The application of single superphosphate,triple super-phosphate,and calcium magnesium phosphate at high plant densities resulted in higher yields and a smaller environmental footprint than the application of diammonium phosphate and monoammonium phosphate.Our scenario analyses suggest that combining the optimal P type and application rate with a high plant density could increase maize yield by 22%.Further,the P resource use efficiency throughout the P supply chain increased by 39%,whereas the P-related environmental footprint decreased by 33%.Thus,simultaneously optimizing the P type and application rate at high plant densities achieved multiple objectives during maize production,indicating that combining P management with cropping techniques is a practical approach to sustainable maize production.These findings offer strategic,synergistic options for achieving sustainable agricultural development.

餐厨垃圾厌氧消化过程养分综合利用研究

餐厨垃圾产量大、危害大、回收价值高,合理利用其中磷的资源价值,可规避其污染风险。综合利用情景分析与物质流分析方法,基于情景分析和养分流动概念模型,对苏南地区餐厨垃圾厌氧消化副产物以3种情景进行处理[沼液进行水处理,沼渣焚烧(情景1,S1);沼液还田,沼渣制有机肥(情景2,S2);沼液进行水处理,沼渣制有机肥(情景3,S3)],以100 t的餐厨垃圾处理规模为参考,分析总磷(TP)的物质流。结果表明:S1的餐厨垃圾中有0.99 kg TP还田,最终有0.96 kg TP进入水稻;S2的餐厨垃圾中有64.05 kg TP还田,最终有62.10 kg TP进入水稻;S3的餐厨垃圾中有8.67 kg TP还田,最终有8.49 kg TP进入水稻。结合经济性能对3种情景进行综合评价,发现S2为餐厨垃圾资源化的最优模式,TP的资源化利用率为91.53%,远高于S1和S3。

“猪-沼-肥-田”模式重金属物质流、迁移转化及生态风险

土壤是守牢耕地红线确保国家粮食安全的重要基础,然而“猪-沼-肥-田”循环农业模式中重金属在生态链中的累积和迁移,尚缺乏系统的调查和研究。以某集约化养殖场为例,在物质流分析的基础上,采用数据协调技术对“猪-沼-肥-田”生态链主要物料中Cu、Zn质量比、赋存形态及分布进行了研究,并对农田施用堆肥所造成的土壤重金属积累进行了评估。结果表明,Cu、Zn流具有数据高度不确定性的特征。通过物质流分析和测量数据的优化校正,研究系统每年随生态链进入农田的Cu、Zn通量分别为472.43 kg和423.01 kg。相对猪粪,厌氧消化使Cu、Zn迁移因子分别下降37.23%和21.98%。沼渣堆肥中,Cu的迁移因子反而从13.92%升高至15.76%,Zn的F_(M)虽有所降低,但其“非稳态”质量比仍然较高(为116.82 mg/kg)。考虑沼肥中重金属形态在自然环境中的不稳定性,厌氧消化物的堆肥处理是一种较优的选择。蒙特卡罗模拟显示,连续施用堆肥,分别经过6.41 a和27.53 a,土壤Cu、Zn质量比即可在背景浓度上翻番。分别经过10.79 a和32.64 a后,Cu、Zn质量比即可超出土壤风险筛选值。农田长期灌施猪粪源有机肥存在潜在生态风险。

SFA基本方法体系及其在战略性资源代谢分析中的应用

物质流分析(SFA)方法作为国家或地区间工业代谢分析的一种手段,目前正越来越广泛的应用于包括各种有色金属元素在内的生命周期评估。文章主要对物质流分析方法的现状及其发展进行简要的介绍。同时,为展示物质流分析方法在战略性资源代谢分析中的应用前景,作者以中国境内的锌元素为例,介绍了运用该方法对锌元素代谢进行分析的一般步骤与效果分析。

红土高压酸浸过程中有价金属的物质流分析

本研究将物质流分析方法(SFA)应用于某红土镍矿高压酸浸工艺。结果表明,虽然高压酸浸工艺已成为处理低品位红土镍矿的主流工艺,但大量固体废物的排放对环境造成极大危害,制约其规模化发展。该高压酸浸工艺年处理红土镍矿能力为321万t,每年将排放300万t高压浸出渣、10万t硫酸盐渣、1.6万t铁铝渣、0.08万t酸浸渣。用镍、钴、锰作为前驱体制备原料,最终流入前驱体制备工艺的物质分别为2.70万t/年、0.24万t/年、0.29万t/年,占比分别为77.14%、75.00%、13.12%。最终流入提钪工艺的超高附加值钪为40.00 t/年,占比为37.70%。高压酸浸工艺可选择性去除98.11%的铁和99.86%的铝。本研究结论对红土镍矿高压酸浸工艺的排放控制和资源循环利用提供了改进建议。

锑火法冶炼过程锑、砷物质流分析

应用物质流分析于锑火法冶炼系统。以锑、砷为目标元素,建立基于生产系统的物质平衡表和物质流图,构建有关系统直接回收率、废物回收率、资源效率的评价指标体系。结果表明:锑的资源效率为89.21%,挥发熔炼、还原熔炼和除杂精炼过程锑的直收率分别为78.79%、91.00%和96.06%。同时,每产出1 t金属锑,会有11.94 kg的砷进入到冶炼系统中。砷为冶炼过程主要杂质元素。重点分析砷在主要单元过程中的分布转化行为。基于物质流分析提出提高锑资源利用效率和清洁生产的建议。

经济-环境系统的物质流分析

经济系统和自然环境通过物质与能量流动相互联系,而物质流与能量流的失衡是环境问题产生的关键原因。物质流分析通过追踪、估算物质在经济-环境系统中的输入、输出和贮存,为物质减量化和可持续发展提供科学依据。元素流分析(substance flow analysis,SFA)和物质流核算与分析(material flow accounting and analysis,MFA)是物质流分析的2种主要方法。SFA追踪特定元素或化合物的流动过程,识别环境问题和潜在的解决途径;而MFA通常把经济系统当作“黑箱”,分析其物质吞吐量。本文从物质流分析的发展和应用研究等方面对SFA和MFA进行了详细的描述,并分析比较了两者间的异同,同时对物质流分析今后的研究重点进行了讨论。

国家尺度上铝的社会流动过程解析

定性解析金属元素的社会流动过程,是定量化开展其物质流分析和资源流研究的前提。铝是世界上生产量与消费量最大的有色金属,同时也是具有良好再生性能的金属。在大量文献调研和专家访谈的基础上,本文基于金属元素物质流分析的一般性框架,详细解析了铝在国家尺度上的社会流动过程,将其概括为3个"四":四阶段、四种库和四种流。四阶段包括:生产阶段、加工与制造阶段、使用阶段、报废与再生阶段。四种库包括:矿产资源库、第一和第二阶段产品的暂时性库存、使用阶段的社会累积库、各种含铝废弃物的堆存库(包括弃矿、尾矿、选冶废渣堆存场和垃圾填埋场等)。四种流即正向流、逆向流、废物流、进出口流。以四阶段为依托,重点刻画了四种流的具体过程,为进行定量化的铝物质流分析及相应的能量流、价值流和环境影响分析提供了基础。

巢湖流域农田生态系统磷代谢分析

采用物质流分析方法,建立巢湖流域农业种植系统的静态磷代谢分析模型,结合统计数据和文献参数,估算了2008年巢湖流域农田生态系统排水含磷来源分配以及流域各县(市)农田生态系统排水的磷含量.结果表明,巢湖流域整个农田生态系统的排向水体的含磷总量为14125.1158t,其中化肥和还田畜禽粪便是巢湖流域农田生态系统磷输入的主要来源,其排入水体的含磷总量分别为37172.0944t和26230.2336t;而肥西县与合肥市辖区是农田种植对水环境影响最大的区域,其农田生态系统排水含磷总量分别为4077.6575t和2849.133t.

磷元素物质流分析研究进展

磷是重要的营养元素,也是不可再生的重要非金属矿物资源。为了分析人类活动对磷流动的扰动,国内外开展了大量磷元素的物质流分析和模拟。综述了磷元素物质流分析的最新研究进展,分析了国内外磷元素物质流研究的特点和不足,并展望了未来相关研究的研究热点和发展方向。从研究尺度看,现有磷元素的物质流研究以全球尺度和国家尺度为主,区域和城市尺度以及企业和产品尺度的研究较少。从研究问题看,现阶段研究主要关注农业或者食品生产和消费对磷流动的影响,对林业、钢铁和能源部门略有涉及。从模型特征看,现有研究以分析流量变化的静态模型为主,考虑存量变化的动态模拟较少。从研究的发展方向看,未来磷物质流的相关分析将关注五大问题:(1)考虑不同驱动力和存量变化的动态模拟;(2)不同层次和尺度的磷足迹研究;(3)磷与其他元素相比对社会经济的重要性;(4)全球变化背景下不同部门磷依赖的脆弱性;(5)磷和其他元素的耦合研究。为了适应未来的研究需求,磷的物质流模拟重点在于开发动态模型,并将物质流分析与多种手段结合,以预测全球变化、社会经济发展、技术变化以及其他重要变化对磷流动的扰动及其相应的环境影响。

我国铅物质流分析研究

从铅的生产、铅制品的加工制造、铅制品的使用和废杂铅的处理等阶段详细地阐述了铅循环的'STAF(stocks and flows)'物质流分析模型.运用此模型分析了2006年我国铅的社会存量变化及其流动状况,并且计算出2000—2006年几项重要指标的平均值分别为:生产阶段的原料自给率PZ=79.28%;生产阶段使用废杂铅的比例PS=19.08%;加工制造阶段的原料自给率MZ=148.91%;加工制造阶段使用废杂铅的比例MS=30.25%;矿石指数R=0.834 9;废铅指数S=0.194 9.在此基础上总结了我国在铅资源循环利用方面的不足,并对铅工业的发展和资源的循环利用提出建议.