Use of macroalgae stored in an Environmental Specimen Bank for application of some European Framework Directives

Different European Framework Directives have established a series of objectives for conservation of the coast, and monitoring tools must be made available to test compliance with these aims. In the present study the use of macroalgae deposited in an Environmental Specimen Bank was evaluated as a possible environmental tool for monitoring the coastal ecosystem. The concentrations of Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn in three species of the genus Fucus (Fucus spiralis, Fucus vesiculosus and Fucus ceranoides) were measured at sampling sites distributed along the coast of Galicia (NW Spain). In the period 1990-2001, the concentrations of the metals were higher in 1990 than in 2001, with the exception of: i) Mn in F. ceranoides and Fe in F. spiralis-F. vesiculosus, for which there were no differences between the sampling periods, and ii) Zn in F. vesiculosus and Fe in F. ceranoides, for which the concentrations were higher in 2001 than in 1990. In the period 2001-2007 concentrations of the metals were more stable, especially in F. ceranoides (e.g. Al, Fe, Hg, Ni and V). The concentrations were also more stable vin F. vesiculosus in 2005 (i.e. Al, Cr, Fe, Mn and Zn). The population density distributions are consistent with the results of the statistical tests. The results indicate that macroalgae of the genus Fucus may be useful for applying different European Framework Directives, given that the macroalgae are sufficiently sensitive to changes in concentrations of metals, and may be suitable for long-term monitoring and used for the detection of increased concentrations of metals (real-time monitoring).     

Migration of As, and H/He ages, in groundwater from West Bengal: Implications for monitoring

From 2002 to 2010 inclusive we monitored concentrations of arsenic (As) and major ions (Ca, Mg, Sr, Na, K, Fe, Mn, Cl, and SO₄) in groundwater from 14 domestic wells and three piezometer nests in a shallow aquifer (<60 m depth), and 3 wells in a deep aquifer (>70 m depth), in southern West Bengal, India. In the deep aquifer, concentrations of As did not change over time despite increases in the concentration of Fe in two wells. The shallow aquifer occurs in two sedimentological settings: palaeo-channel and palaeo-interfluve. At the top of the shallow aquifer of the palaeo-channel, decreases in all constituent concentrations with time, and an ³H/³He age of 1.4 years, proves that the aquifer is beginning to be flushed of pollutants. In As-polluted groundwater (>50 μg/L As) tapped from deeper grey sands of the shallow, palaeo-channel, aquifer, concentrations of As were mostly stable over time, but both increases and decreases occurred with time in response to downward migration of the chemically-stratified water column. In groundwater tapped from Pleistocene brown sands, the concentration of As remained either low and stable (<2 μg/L As), or increased at rates up to 34 μg/L per year. The increases were caused by the flow of As-rich groundwater either downward into brown sand at the base of palaeo-channels, or laterally into a confined, unpolluted, palaeo-interfluvial, aquifer of brown sand that lies regionally beneath a palaeosol.Under the present pumping regime, the prognosis for As-pollution in the shallow aquifer is complex. Wells in brown sand may become polluted over timescales of as little as 2 years, whilst some wells tapping As-polluted groundwater from grey sand will become fit for potable use (<50 μg/L) within a few decades. The evidence of flushing, and of declining As in some of the groundwater from palaeo-channels, which are conduits for recharge of the confined, As-free, palaeo-interfluve aquifer, and probably also the deeper aquifer, offers hopes that the spread of As-pollution will be limited.     

Distribution and mobility of arsenic in soils of a mining area (Western Spain)

High levels of total and bioavailable As in soils in mining areas may lead to the potential contamination of surface water and groundwater, being toxic to human, plants, and animals. The soils in the studied area (Province of Salamanca, Spain) recorded a total As concentration that varied from 5.5 mg/kg to 150 mg/kg, and water-soluble As ranged from 0.004 mg/kg to 0.107 mg/kg, often exceeding the guideline limits for agricultural soil (50 mg/kg total As, 0.04 mg/kg water-soluble As). The range of As concentration in pond water was < 0.001 μg/l-60 μg/l, with 40% of samples exceeding the maximum permissible level (10 μg/l) for drinking water. Estimated bioavailable As in soil varied from 0.045 mg/kg to 0.760 mg/kg, around six times higher than water-soluble As fraction, which may pose a high potential risk in regard to its entry into food chain. Soil column leaching tests show an As potential mobility constant threatening water contamination by continuous leaching. The vertical distribution of As through soil profiles suggests a deposition mechanism of this element on the top-soils that involves the wind or water transport of mine tailings. A similar vertical distribution of As and organic matter (OM) contents in soil profiles, as well as, significant correlations between As concentrations and OM and N contents, suggests that type and content of soil OM are major factors for determining the content, distribution, and mobilization of As in the soil. Due to the low supergenic mobility of this element in mining environments, the soil pollution degree in the studied area is moderate, in spite of the elevated As contents in mine tailings.     

Pollution situation and possible markers of different sources in the Ordos Region, Inner Mongolia, China

In order to investigate the pollution situation for a fast-developing industrial area at its first stage, a systematic study on the gaseous and particulate pollution in the Ordos Region of Inner Mongolia was performed during 9-24 September 2005. The gases SO₂, NO_x, O₃, CO, and the particulates PM₁₀ and PM_2.5 were sampled at five sites in Ordos. Species measured in aerosol were 21 elements, 10 ions, organic carbon (OC), elemental carbon (EC), and the acid-buffering capacity of particulates. Possible markers of sources for different transport directions were firstly investigated, which was a new attempt for clarification of regional transport with different directions. None of the gases exceeded the national standards of China. PM_2.5 contributed most to PM₁₀ at the background site, indicating the greatest contribution of regional transport. Organic matter, crustal material, and sulfate ion were the three dominant species of aerosol, followed by EC, NO₃⁻, NH₄⁺, trace elements, and other ions. The acidity of PM_2.5 was higher than that of PM₁₀, and the buffering capacity in PM₁₀ was higher than that in PM_2.5. Four peaks of pollution aerosol were observed during the 3-week study sampling period, separated by periods of cleaner air. Back-trajectories revealed that the peaks came from the south and the cleaner air from the north. It is the first time to find different markers for aerosols from different transport directions in Ordos. S and Pb, as well as SO₄²⁻, NO₃⁻, and NH₄⁺ appeared to be good markers of southern aerosol in the Ordos, since all showed four clear peaks on days dominated by southern direction. Extremely high peaks of Al and Ti on the 16th and 17th, especially at the dust-monitoring site, indicated good markers for soil dust. Ca and Mg showed earlier peaks on the 16th at the western site, indicating possible markers for western aerosol.     

冷凝法回收石脑油卸车尾气的工艺改进

对吉林石化公司乙烯厂石脑油卸车栈台卸车尾气进行了治理,使多年来直排大气、污染环境、造成资源浪费的尾气排放问题得以改善,并取得了较好的经济效益和环境效益。     

Energy, economic and environmental (3E) analysis of a micro gas turbine employed for on-site combined heat and power production

This paper studies the optimization of micro turbine application to meet the electrical, heating and cooling loads of a building by energy, economics and environmental analysis. In this study following three cases are considered: 1: A simple micro gas turbine to meet the electrical power of the building. 2: A simple micro gas turbine to meet the electrical power of the building as well as the power required by heat pump and mechanical refrigerator needed for heating, cooling and domestic hot water (DHW) systems. 3: A CHP micro gas turbine to meet the electrical power of the building as well as part of the power required by heat pump and mechanical refrigerator needed for heating, cooling and DHW systems. The remaining part of the power for heat pump and mechanical refrigerator is provided by the exhaust gases.The research shows that the initial investment is a considerable portion of electricity cost. For an annual interest rate of 10% this portion ranges from 31 to 40% depending on system design configurations, and the lower interest rates results in the smaller portions. It is also concluded that the number of turbine units and electricity cost are highly depended on electricity consumption management.     

TEMPORAL POST-DISCHARGE REACTIONS IN PLASMA-CHEMICAL DEGRADATION OF SLAUGHTERHOUSE EFFLUENTS

The plasma-chemical degradation of bovine blood effluents provided by a slaughterhouse plant is achieved by exposing the dilute blood target to a gliding discharge in humid air. The several steps of the degradation were ascribed to the oxidizing and acidifying properties of the parent species formed in the discharge (e.g., mainly °OH and °NO and their derivatives). The oxidation reactions go on after the discharge is switched off and evidence Temporal Post-Discharge Reactions (TPDR). This demonstrates that less reactive moieties than °OH and °NO – tentatively H₂O₂ and ONO₂H – are concerned in TPDR and probably also involved in the main degradation process performed under plasma conditions. Industrial effluents involve large quantities of sodium citrate additive (10^?2 mol L^?1), which is first degraded according to zero order kinetics, folllowed by a 1st order kinetic step (k₁ = 0.2 min^?1) ascribed to the diffusion controlled degradation of hemoglobin (Hb).     

家具及装饰用胶对室内环境的影响

对家具及装饰用胶粘剂对室内空气污染进行了实地测试和调研，分析了污染物质的来源、品种及对人体的危害。在调研基础上，提出了治理污染的措施。     

ELECTROCHEMICAL DESTRUCTION OF COMPLEX CYANIDE

A batch electrochemical cell consisting of a pair of stainless steel wire-mesh electrode was used to electrochemically decompose concentrated cuprous cyanide waste solution. The concentrations of free, complex, and total cyanide were measured as a function of electrolysis time for various cell currents. The total cyanide concentration in the waste solution was reduced from 1200 ppm to less than 50 ppm with an electric power consumption on the order of 14-34 kWH per kilogram of cyanide destroyed. Copper was recovered in its metallic form at the cathode and as CuO deposit at the anode with a combined recovery rate greater than 90%. In addition, cyanide complex was found to chemically decompose at the stainless steel meshes, rendering a coulombic efficiency greater than 100% in some of the experimental runs.