Environmental,economic and social costs and benefits of a packaging waste management system: A Portuguese case study

The impact of the management of packaging waste on the environment, economic growth and job creation is analyzed in this paper. This integrated assessment intends to cover a gap in the literature for this type of studies, using the specific case study of the Portuguese packaging waste management system (SIGRE).The net environmental benefits associated with the management of packaging waste, are calculated using the Life Cycle Assessment methodology. The results show that, for the categories studied, the impacts associated to SIGRE's various activities are surpassed by the benefits associated to material and energy recovery, with special focus on recycling. For example, in 2011 SIGRE avoided the emission of 116 kt CO₂ equiv. – the equivalent carbon emission of the electricity consumption of 124.000 households in Portugal.The economic impact of SIGRE is evaluated through Input–Output Analysis. It was found that SIGRE's activities also have a significant economic impact. For example, their added value are ranked amongst the upper third of the economic activities with highest multiplier effect at national level: this means that for each Euro of value added generated within SIGRE, 1.25 additional € are added to the rest of the economy (multiplier effect of 2.25).Regarding the social impacts of SIGRE, the number of direct jobs associated with the system is estimated to be more than two thousand and three hundred workers. Out of these, 83% are connected to the management of municipal waste packaging (selective collection and sorting), 15% are connected to the management of non-municipal packaging waste and only 2% are connected to the Sociedade Ponto Verde (SPV, green dot society in English) – the management entity responsible for SIGRE.In general terms, the results obtained provide quantitative support to the EEA (2011) suggestion that moving up the waste hierarchy – from landfilling to recycling – creates jobs and boosts the economy.     

Environmental consequences of recycling aluminum old scrap in a global market

Nowadays, aluminum scrap is traded globally. This has increased the need to analyze the flows of aluminum scrap, as well as to determine the environmental consequences from aluminum recycling. The objective of this work is to determine the greenhouse gases (GHG) emissions of the old scrap collected and sorted for recycling, considering the market interactions. The study focused on Spain as a representative country for Europe. We integrate material flow analysis (MFA) with consequential life cycle assessment (CLCA) in order to determine the most likely destination for the old scrap and the most likely corresponding process affected. Based on this analysis, it is possible to project some scenarios and to quantify the GHG emissions (generated and avoided) associated with old scrap recycling within a global market. From the MFA results, we projected that the Spanish demand for aluminum products will be met mainly with an increase in primary aluminum imports, and the excess of old scrap not used in Spain will be exported in future years, mainly to Asia. Depending on the scenario and on the marginal source of primary aluminum considered, the GHG emission estimates varied between −18,140 kg of CO₂ eq. t⁻¹ and −8427 of CO₂ eq. t⁻¹ of old scrap collected. More GHG emissions are avoided with an increase in export flows, but the export of old scrap should be considered as the loss of a key resource, and in the long term, it will also affect the semifinished products industry. Mapping the flows of raw materials and waste, as well as quantifying the GHG impacts derived from recycling, has become an essential prerequisite to consistent development from a linear toward a circular economy (CE).     

水泥脱硝综合评估分析——以四川省某水泥企业为例

在分析四川省某水泥企业两条新型干法生产线分别采用低氮燃烧技术、SNCR烟气脱硝工程技术特点的基础上,评估了综合采用控制NO X措施后的运行效果,脱硝的经济技术可行性,并从NO X控制技术、环境管理、环境标准以及环境经济等方面提出相关的配套政策建议。     

Anthropogenic land use substantially increases riverine CO2 emissions

Carbon dioxide (CO₂) emissions from inland waters to the atmosphere are a pivotal component of the global carbon budget. Anthropogenic land use can influence riverine CO₂ emissions, but empirical data exploring cause-effect relationships remain limited. Here, we investigated CO₂ partial pressures (pCO₂) and degassing in a monsoonal river (Yue River) within the Han River draining to the Yangtze in China. Almost 90% of river samples were supersaturated in CO₂ with a mean ± standard deviation of 1474 ± 1614 µatm, leading to emissions of 557 - 971 mmol/m²/day from river water to the atmosphere. Annual CO₂ emissions were 1.6 - 2.8 times greater than the longitudinal exports of riverine dissolved inorganic and organic carbon. pCO₂ was positively correlated to anthropogenic land use (urban and farmland), and negatively correlated to forest cover. pCO₂ also had significant and positive relationships with total dissolved nitrogen and total dissolved phosphorus. Stepwise multiple regression models were developed to predict pCO₂. Farmland and urban land released nutrients and organic matter to the river system, driving riverine pCO₂ enrichment due to enhanced respiration in these heterotrophic rivers. Overall, we show the crucial role of land use driving riverine pCO₂, which should be considered in future large-scale estimates of CO₂ emissions from streams. Land use change can thus modify the carbon balance of urban-river systems by enhancing river emissions, and reforestation helps carbon neutral in rivers.     

关于环境监测中重金属污染现状及对策研究

随着我国经济正在不断发展,环境污染问题也在日益加剧,严重影响生态环境的稳定发展。尤其是重金属污染,会危害人们的身体健康,而且重金属一旦进入人体,就难以有效地排除。因此,相关环境部门应该重视重金属污染处理,提高环境监测的效率,制定针对性监测与处理方案,避免其影响人们的正常生活。基于此,本文分析了环境监测中重金属污染的现状,并阐述了相关对策,仅供参考。     

A data synthesis on the biochar properties and implications for air,soil, and water quality in Brazil

Biochar has been intensively researched worldwide. In Brazil, there is a variety of feedstock production that can be turned into soil amendments of high performance through biochar conversion, especially solid wastes. However, advances in biochar research in Brazil have not been systematically evaluated to indicate possible gaps and suggest future research for eco-friendly applications. Thus, in this work we evaluated biochar properties and effects on air, water, and soil quality based on data gathered from researches performed in Brazil. Biochar has been mainly evaluated as soil conditioner (37%), material characterization (17%), water treatment (12%), and greenhouse gases emissions (9%). Based on the data synthesis of 68 feedstocks used for biochar production, we observed that the pyrolysis temperature profoundly affects biochar properties. Meta-analysis indicated benefits of biochar addition to soils for chemical, physical, microbiological and biochemical attributes that have resulted in increases in root growth (+30%), and plant shoots (+45%). Pyrolysis temperature and feedstock are key choices to design biochar properties aiming to retain dyes, aromatic hydrocarbon, pesticides, and metals in water and wastewater treatment. It was also observed an increase in CO₂ and a decrease in N₂O emissions after biochar application to soils in short-term experiments. Although there is a growing interest in the development of electrochemical sensors and biochar-based fertilizers, technological applications of biochar are still incipient in Brazil. Future research should prioritize long-term and mechanistically evaluations of biochar under field conditions and the development of eco-friendly technological applications.     

流体载热远红外气相辐射加热效果及影响因素研究

在“选择性催化还原法(SCR)脱硝-湿法脱硫”系统中,用SCR脱硝后回收的部分废热作为低温热源对湿法脱硫后的烟气进行远红外气相辐射加热,则可实现低成本、高效、简便的烟气再热.以导热油为载热流体,对远红外气相辐射加热湿法脱硫烟气的效果及其影响因素进行了研究.结果表明:流体载热远红外气相辐射加热方式较传统加热方式效果明显;加热终温随导热油温度和进口气体温度升高而升高,而随辐射距离、进口气体流量增大而降低;加热速率随导热油温度升高而增大,而随辐射距离、进口气体温度和进口气体流量增加而减小;加热管所涂涂料的性能是影响辐射加热效果的重要因素之一.     

固体废物焚烧处置及其清洁发展机制

包含化石碳(如塑料等)在内的废物焚烧处置和露天燃烧是废物部门中最重要的CO₂排放来源之一. 在全国节能减排大背景下,废物焚烧发电成为温室气体减排的有效途径. 对我国固体废物焚烧处置现状及趋势进行了分析,同时研究了国内城市固体废物和危险废物焚烧的区域特征. 结果表明:随着经济发展和废物产生量的急剧增长,废物焚烧处置技术必将成为我国未来固体废物处置的主要方式;伴随着废物焚烧行业的发展,有大量项目可以注册CDM (清洁发展机制)项目,可为温室气体减排做出较大的贡献.      

壳聚糖吸附剂脱除燃煤模拟烟气中汞的试验研究

采用在线检测法检测了纯氮气气氛下及模拟烟气气氛下高分子化合物壳聚糖吸附剂对单质汞的吸附特性,结果表明,温度升高有利于脱汞反应的进行,纯氮气氛下脱除汞单质效率不高,60℃时为28.85%, 120℃时升为38.46%;氮氧化物、硫氧化物对汞的脱除有一定的促进作用,在模拟烟气气氛下120℃时吸附剂出口平衡吸附率为48.05%,平均吸附率约68%.红外光谱分析揭示了壳聚糖吸附剂吸附烟气中汞的机理为2个游离氨基与2个羟基鳌合1个汞原子或汞离子.     

模拟烟气条件下野生混合微藻的培养

开发利用生物质能是解决能源紧张和一系列全球环境问题的有效途径之一.微藻是一种具有发展前途的新型生物质能原料,利用烟气培养微藻不仅为生物质能的开发提供了新的途径,而且能够直接削减烟气CO₂的排放,对于减缓全球气候变化具有积极意义.以野生混合微藻为对象,利用模拟烟气在柱状光生物反应器内培养微藻,通过180 d的培养,考察光照条件和CO₂对微藻生长的影响及光照条件对细胞粗脂肪含量的影响.结果表明:驯化后的混合微藻对CO₂具有生理敏感性,烟气中的CO₂可以明显提高其生长速率;全天光照可提高微藻生长速率,并有利于生长速率和微藻生物量的稳定;在微藻生物量和光合有效辐射日总量一定的条件下,全天24 h光照比12 h∶12 h更有利于细胞粗脂肪的积累.