Vol. 5, No. 1 (2017): Regular Issue

The environmental load of different steelmaking processes at two typical steel production facilities in Jiu Steel was analyzed and evaluated by Life Cycle Assessment. The environment impacts of different steelmaking processes were classified by Environmental impact classification methods offered by the GaBi software, with the addition of characteristic factors; The environment impacts of producing 1 ton steel was quantified. Results shows that the major environmental impacts of Basic Oxygen Furnace steelmaking process are toxicity to aquatic ecosystems, toxicity to humans, depletion of fossil energy, and depletion of mineral resources, with these resulting from processes of coking, sintering, blast furnace iron-making, and waste iron recycling. Climate change, toxicity to humans, toxicity to aquatic ecosystems, and solid waste production make up 30%, 95%, 50%, and 90% respectively of the total environmental impact. The major environmental impacts of Electric Arc Furnace steelmaking process are climate change, acidification, and photochemical ozone formation from molten iron and electric steelmaking processes. A reliable theoretical basis for steelmakers to adjust the two different processes is provided through this work. The research may also contribute to detecting potential for improvement, including for energy saving and for reducing the environmental load of various aspects of the production process. Steelmakers can therefore improve and optimise their production processes.

As part of efforts to reduce the eutrophying load to Lake Victoria, a wastewater treatment system at one of the sugar factories in Kenya was evaluated with the ecosystem ecology method emergy accounting. As a comparison a traditional cost analysis was also performed. The analysis included the local and imported ecosystem services. After preliminary treatment the effluent was discharged into a series of 12 stabilisation ponds. The removal of COD and TSS was high, whereas phosphorus concentrations were reduced by less than 20 %. The monetary costs were dominated by operation and management cost, some of which could probably be reduced by more effective management. The local ecosystem services in emergy terms contributed only 1% (or 1,000 Em$) to the treatment system. Imported ecosystem services in purchased lime contributed more to the treatment system, 22% (or 24,600 Em$). Since the land costs in the area were low, land demanding treatment methods using free local ecosystem services, could be cost effective choices for wastewater management. Ecosystem ecology methods as emergy accountings can guide these choices by revealing the additional contribution of free ecosystem services. Emergy accountings seem to need further clarification regarding differences in micro-/macroeconomic views.

Regional diversity of economic situation and production levels lead to significant differences of regional carbon emissions between cities, gravity center can dynamically and clearly reflect the trajectory changes of regional economic development and carbon emissions. In this paper, gravity center is used to depict the dynamic changes of industrial GDP and indus-trial carbon emissions in Guangdong, China from the past decade. By analyzing the center movements, the industrial centers and carbon center had similar tracks in west direction. Energy consumption by Western Guangdong increased rapidly during the study period, with the gravity center of carbon emissions moving in southwest direction. The method would help to reveal the effects of transfer on industrial carbon emissions, and simulate the further procedures of regional industrial transfer.

This paper analyses the water quality characteristics of a remote and pristine basin, the Gallina small catchment, located in the Piemonte Region (NW Italy). In particular, the ion content of river water and precipitation are assessed for two distinct periods (October-December of years 1992 and 2011). These time frames are characterized by a change of air quality management rules for the study area which came into force after year 2000. Furthermore, late Autumn months, which are considered in this study, are characterized by a peak of recorded precipitations in the area under study. Moreover, this is a period of the year where atmospheric emission intensity and distribution are greater with respect to Spring and Summer. The chemical nature of the monitored water body was assessed through the use of Piper diagram. Research found evidence of erosional processes, which chemically altered the water compared to the quality of precipitation. The signature of air chemistry was also evident, through a shift to less sulphate, after the change of air quality regulations introduced in year 2000. The presence of marine ions, in case of major weather perturbations, typical of the late Autumn in the monitored area, was recorded. This fact was particularly evident for the month of November 2011, in association to a major flooding event occurred in the Piemonte Region. The presence of a minor ionic component, associated to rainfall waters, depending upon soil particle resuspension and transport was also detected. Finally, the prevailing origin of the measured ions was defined. The results show the importance of improved management actions, which should be taken in order to further reduce the trans-boundary atmospheric pollution, which constitutes a threat to water quality and a further element of indirect water pollution transfer across different areas.

Ecological models play an important role in lake eutrophication research and management. Many integrated system models have been developed since the 1970s. However, their fixed structure limits flexibility and applicability in urban landscape lakes. An ecosystem dynamic model was constructed to simulate ecological restoration of an urban shallow lake under the interference of chlorine. The model was validated using the monitoring data of an urban lake in Guangzhou. The correlation coefficient (R), root mean squareerror-observations standard deviation ratio (RSR) and index of agreement (IOA) were calculated to evaluate accuracy and reliability of the model and their values for all of the compared variables were significant, less than 0.7, and larger than 0.6, respectively, which reflected good agreement of the model. The results give important insight into understanding eutrophic dynamic process in urban shallow lake. Furthermore, the exhibit model has great applicability in management of urban shallow lakes.

Protozoa and filamentous bacteria identification in Mixed Liquor (ML) allowed to obtain detailed information about the performance of five Wastewater Treatment Plants (WWTPs), placed in La Spezia’s District. Microfauna analysis showed the prevalence of testate amoebas (Euglypha spp. prevalent), rotifers and attached ciliate Epistylis plicatis. Low organic load, high sludge-age and high concentration of dissolved oxygen (DO) were well correlated to the growth of Vorticella campanula and Vaginicola sp. Testate amoebas (Euglypha sp. and Arcella sp.) were the most representative group in WWTPs treating also olive mills effluents. Sludge Biotic Index (SBI) showed, for the investigated plants, an optimal to good depuration efficiency (I and II class quality) but it seemed not adequately responsive when olive mills wastewater (rich in phenols) was mixed with the municipal one. Further investigations should be conducted to explain this result. Filamentous bacteria analysis revealed a higher sensitivity of microorganisms to both influent chemical characteristics and WWTPs operational parameters. In most part of the WWTPs, dysfunctions due to the proliferation of filamentous bacteria were detected. In all WWTPs subjected to foaming, the morphotype Nocardia Amarae Like Organisms (NALO), associated with Type 1851 and 0041, was identified as responsible of the foaming. Type 0092 caused a bulking episode in La Spezia WWTP. Haliscomenobacter hydrossis prevailed in the Mixed Liquor (ML) of a plant treating also olive mills wastewater, while Type 0803, 0675 and 1701 were abundant in plants receiving wastewater produced by meat-processing industries. On the whole, filamentous bacteria community analysis represented a more sensitive tool to characterize the activated sludge plant performances in light of providing an adequate management.

Low-carbon city is the key to achieving low-carbon future. Carbon emission accounting is the most fundamental step. Carbon emissions from urban energy use are the principal and key bodies of global carbon emissions reduction, which are the most important parts of urban carbon emissions. The goal of this study is to construct a novel hybrid analysis model framework (PEIO), a combination of Process Analysis (PA) and Environmental Input-Output Analysis (EIOA), to access the carbon emissions on urban energy use from life cycle perspective, including the carbon emissions from end-use sector activities, cross-boundary traffic and the embodied energy of key urban materials.