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1.
Pollution prevention (P2) assessment was conducted by applying the three R’s, reduce, reuse, and recycle, in a chemical industry for the purpose of reducing the amount of wastewater generated, reusing paint wastewater in the manufacture of cement bricks, recycling cooling water, and improving water usage efficiency. The results of this study showed that the annual wastewater flow generated from the paint manufacturing can be reduced from 1,100 m3 to 488.4 m3 (44.4% reduction) when a high-pressure hose is used. Two mixtures were prepared. The first mixture (A) contains cement, coarse aggregate, fine aggregate, Addicrete BVF, and clean water. The second mixture (B) contains the same components used in the first mixture, except that paint wastewater was used instead of the clean water. The prepared samples were tested for water absorption, toxicity, reactivity, compressive strength, ignitability, and corrosion. The tests results indicated that using paint wastewater in the manufacture of the cement bricks improved the mechanical properties of the bricks. The toxicity test results showed that the metals concentration in the bricks did not exceed the U.S. EPA limits. This company achieved the goal of zero liquid discharge (ZLD), especially after recycling 2,800 m3 of cooling water. The total annual saving could reach $42,570 with a payback period of 41 days.

Implications: This research focused on improving the water usage efficiency, reducing the quantity of wastewater generated, and potentially reusing wastewater in the manufacture of cement bricks. Reusing paint wastewater in the manufacture of the bricks prevents the hazardous pollutants in the wastewater (calcium carbonate, styrene acrylic resins, colored pigments, and titanium dioxide) from entering and polluting the surface water and the environment. We think that this paper will help to find the most efficient and cost-effective way to manage paint wastewater and conserve fresh water resources. We also believe that this paper provides a rich agenda for future research in water conservation and industrial wastewater reuse subjects.  相似文献   


2.
Ambient suspended particulate (PM2.5, PM2.5–10, TSP) was collected from June 1998 to February 2001 in Taichung, central Taiwan. In addition, the related water-soluble ionic species (Cl, NO3, SO42−, Na+, NH4+, K+, Mg2+, Ca2+) and metallic species (Fe, Zn, Pb, Ni) were also analyzed in this study. The results showed that the concentrations of particulate mass are higher in the traffic site (CCRT) than the other sampling sites in this study. Also, the fine particle (PM2.5) concentration is the dominant species of the total suspended particles in Taichung, central Taiwan. The dominant species for PM2.5 are sulfate and ammonium at all sampling sites during the period of 1998–2001. The results of diurnal variation at THUC sampling site are also discussed in this study. Overall, acidic and secondary aerosol (Cl, NO3, SO42− and NH4+) is a more serious air pollutant issue in southern and central Taiwan than at several sites around the world. Therefore, ambient suspended particulate monitoring in Taichung, central Taiwan will be continuing in our following study to provide more information for the government to formulate environmental strategy.  相似文献   

3.
The six chemical reaction mechanisms for photochemical smog described in Pan I (Leone and Seinfeld, 1985, Atmospheric Environment 19,437–464) were used to study the effect of input parameters on volatile organic compound (VOC) control requirements needed to meet the National Ambient Air Quality Standard for ozone. The parameters studied were initial VOC composition, dilution rate, post 8-a.m. emissions, base case (present day) O3 levels, entrainment from aloft of VOC and ozone and initial VOC/NOx ratio. The Empirical Kinetic Modeling Approach (EKMA) was used to generate ozone isopleths for each chemical mechanism. The VOC control needed to reduce the maximum ozone concentration from some present day value to 0.12 ppm, assuming no NOx control and a specified initial VOC/NOx ratio, was calculated using the six chemical reaction mechanisms. The initial VOC/NOx ratio was found to have the largest effect of all the parameters studied on VOC control requirements. Choice of chemical mechanism, ozone and VOC entrainmem from aloft, base-case ozone and the composition of the initial VOC mixture also had a large effect on predicted control requirements. To reduce the degree of uncertainty in control predictions using EKMA it is necessary to establish as accurately as possible the composition of urban air in early morning. Also, because of the substantial effect the choice of chemical mechanism has on the predicted control requirements using EKMA, it is important that future work continues to be directed toward evaluating candidate chemical mechanisms with respect to their ability to simulate atmospheric smog chemistry.  相似文献   

4.
This paper synthesizes data on aerosol (particulate matter, PM) physical and chemical characteristics, which were obtained over the past decade in aerosol research and monitoring activities at more than 60 natural background, rural, near-city, urban, and kerbside sites across Europe. The data include simultaneously measured PM10 and/or PM2.5 mass on the one hand, and aerosol particle number concentrations or PM chemistry on the other hand. The aerosol data presented in our previous works (Van Dingenen et al., 2004, Putaud et al., 2004) were updated and merged to those collected in the framework of the EU supported European Cooperation in the field of Scientific and Technical action COST633 (Particulate matter: Properties related to health effects). A number of conclusions from our previous studies were confirmed. There is no single ratio between PM2.5 and PM10 mass concentrations valid for all sites, although fairly constant ratios ranging from 0.5 to 0.9 are observed at most individual sites. There is no general correlation between PM mass and particle number concentrations, although particle number concentrations increase with PM2.5 levels at most sites. The main constituents of both PM10 and PM2.5 are generally organic matter, sulfate and nitrate. Mineral dust can also be a major constituent of PM10 at kerbside sites and in Southern Europe. There is a clear decreasing gradient in SO42? and NO3? contribution to PM10 when moving from rural to urban to kerbside sites. In contrast, the total carbon/PM10 ratio increases from rural to kerbside sites. Some new conclusions were also drawn from this work: the ratio between ultrafine particle and total particle number concentration decreases with PM2.5 concentration at all sites but one, and significant gradients in PM chemistry are observed when moving from Northwestern, to Southern to Central Europe. Compiling an even larger number of data sets would have further increased the significance of our conclusions, but collecting all the aerosol data sets obtained also through research projects remains a tedious task.  相似文献   

5.
Environmental Science and Pollution Research - Feedback between hydrologic variations and chemical weathering is thought to play a crucial role in modulating global carbon cycling. The mechanisms...  相似文献   

6.
This study provides the first comprehensive report on mass concentrations of particulate matter of various sizes, inorganic and organic gas concentrations monitored at three sampling sites in the city of Palermo (Sicily, Italy). It also provides information on the water-soluble species and trace elements. A total of 2054 PM10 (1333) and PM2.5 (721) daily measurements were collected from November 2006 to February 2008. The highest mass concentrations were observed at the urban stations, average values being about two times higher than those at the suburban (control) site. Time variations in PM10 and also PM10–2.5 were observed at the urban stations, the highest concentrations being measured in autumn and winter. CO, NOx, NO2, benzene, toluene and o-xylene concentrations peaked in autumn and winter, a pattern similar to those recorded for PM10 and PM10–2.5 mass levels, indicating the importance of traffic emissions in urban air pollution. 91% and 51% of the benzene measurements exceeded the limit of 5 μg m?3 at the two urban monitoring sites. Trace elements (As, Ba, Cr, Cu, Mo, Pb, Sb) suspected of being introduced into the atmosphere mainly by anthropogenic activities, were highly enriched with respect to local soil. Results indicate that a large fraction of PM10 (31–47% in weight) and PM2.5 (29% in weight) is made up of water-soluble ions. Ammonium sulphate and nitrate particles accounted for 14–29 wt% of particulate matter mass concentrations. Crustal and marine components, combined, account for 41% and 49% in PM2.5 and PM10, respectively. The calculated deficits in Cl- and NH4+ ions suggest that a proportion of these ions are lost, via the formation of gaseous NH4Cl or HCl and NH3.  相似文献   

7.
The aim of this study was to relate the results obtained by chemical methods, used to assess environmental (bio)availability, with the ecotoxic response and bioaccumulation of trace elements (TE) by the earthworm Eisenia fetida exposed to field-contaminated, metal-polluted soils from a sulphide mine. The extracting solution 0.5 M NH4CH3COO, 0.5 M CH3COOH and 0.02 M EDTA (pH 4.7), was able to predict environmental bioavailability of TE to E. fetida. However, the toxicological bioavailability could not be predicted from the results of the chemical extractions or from the bioaccumulation results: E. fetida reproduction was higher in soils where environmental bioavailability of TE and bioaccumulation values were also higher. In this study, the toxic response of the organism seemed to be more influenced by the overall nutritional status of the soil (e.g. pH, organic matter, plant nutrient availability and cation exchange capacity) than by its TE contamination. In the case of anthropogenic multi-contaminated sites, the different soil characteristics exert an important and confounding influence in the toxic response and the relationship between different bioavailable fractions cannot be easily established, emphasising the need to combine results from chemical methods with those from bioassays when evaluating the bioavailability of TE in these soils.  相似文献   

8.
Numerical modeling of scavenging processes has been compared with data obtained for rainwater and aerosol chemistry at Serra do Navio, in the state of Amapá in the Brazilian Amazon region. Sulfate, nitrate and ammonium concentrations were determined in rainwater samples collected from May 1995 until June 1997. The levels of these same chemicals were also determined in aerosols for the same period and region. Scavenging processes have been evaluated on a rainfall event basis, via numerical modeling, in order to simulate the rainwater concentrations and compare them with the observed data. RAMS (Regional Atmospheric Modeling System) was used to simulate cloud structures. A model of below-cloud scavenging was evaluated, as well. The determinations made from the results of the scavenging model are the following: a) aerosol vertical profiles are quite important to rainwater concentrations; b) modeled sulfate in rainwater is a better fit to the observed data values than ammonium and nitrate; c) the obtained sulfate aerosol concentrations samples are similar to ones found in the literature, although the sulfate concentrations in rainwater are much lower than other studies in the literature; d) the in-cloud scavenging process dominates, e) our modeled results, using an input gas vertical profile extracted from the ABLE2B experimental data set, present a smaller ratio between gas and aerosol scavenging than found in other studies in the literature, other studies may have had larger rainfall times, which increase the importance of gas phase scavenging.  相似文献   

9.
This study quantified the masses of 14 pesticides deposited as wet (precipitation) versus dry (gaseous and particle) atmospheric deposition at a research farm in southwestern Manitoba, Canada. The concentration in air of these pesticides was also measured. Total bulk deposition amounts (wet + dry) ranged from 0.009 to 2.3 μg m?2 for the 12 pesticides detected, and for the six pesticides with both wet and dry deposition detections, dry deposition contributed 12–51% of the total deposition over the crop growing season. Although not applied at the site, eight herbicides registered for use in Canada, as well as lindane (γ-HCH), were all frequently detected (92–100%) in the 12 air samples analyzed during the crop growing season, with by-product isomer α-HCH (75%), clopyralid (50%) and atrazine (8%) detected to a lesser extent. The chemical’s physicochemical properties and the relative mean mass of each agricultural pesticide applied in the province of Manitoba and in a 13 km radius were significant parameters in explaining the trends in the concentrations of pesticides detected in our samples. The important contribution of dry deposition to total pesticide deposition warrants greater attention in arid and semi-arid areas such as the Prairie Region of Canada, also because under a changing climate this region is estimated to experience more severe droughts while the more favorable conditions predicted for pest infestations could lead to increased pesticide applications in agricultural and urban areas.  相似文献   

10.
Operator splitting applied to cloud micro-physical and multiphase chemical process causes the so-called operator splitting errors in addition to other numerical errors when used in numerical models. Operator splitting is mainly used due to limited computer resources or for historical reasons. Unfortunately, it is impossible so far to theoretically estimate either the order of magnitude or the tendency of the splitting errors in complex non-linear systems such as mutually interacting cloud chemical and micro-physical processes.The present study systematically investigates the splitting error mentioned above, by numerical means to define valid ranges of the applicability of the method of operator splitting to those systems. Results of the current study show that de-coupling intervals larger than 100 s cause an underestimation of the total liquid water content as well as the particle radius of the order of 10% for simulation periods of 1000 s. The maximum overprediction of the total content of dissolved material in the particles is of the order of about 20% for de-coupling intervals of 10–15 min. The error in the sulphate production contributes about 50% to the discrepancy in total aerosol content. Since the de-coupling intervals between dynamical, micro-physical, and chemical processes in most recent air quality models are considerably longer than 15 min, the consequences of the application of operator splitting requires further investigation with respect to predicted aerosol formation, cloud water content, deposition rates, photo-chemistry, cloud optical properties, etc.  相似文献   

11.
Environmental Science and Pollution Research - The massive use of pesticides brings considerable environmental and human health impacts. This study conducted an overall assessment of the ecological...  相似文献   

12.
We report on ambient atmospheric aerosols present at sea during the Atlantic–Mediterranean voyage of Oceanic II (The Scholar Ship) in spring 2008. A record was obtained of hourly PM10, PM2.5, and PM1 particle size fraction concentrations and 24-h filter samples for chemical analysis which allowed for comparison between levels of crustal particles, sea spray, total carbon, and secondary inorganic aerosols. On-board monitoring was continuous from the equatorial Atlantic to the Straits of Gibraltar, across the Mediterranean to Istanbul, and back via Lisbon to the English Channel. Initially clean air in the open Atlantic registered PM10 levels <10 μg m?3 but became progressively polluted by increasingly coarse PM as the ship approached land. Away from major port cities, the main sources of atmospheric contamination identified were dust intrusions from North Africa (NAF), smoke plumes from biomass burning in sub-Saharan Africa and Russia, industrial sulphate clouds and other regional pollution sources transported from Europe, sea spray during rough seas, and plumes emanating from islands. Under dry NAF intrusions PM10 daily mean levels averaged 40–60 μg m?3 (30–40 μg m?3 PM2.5; c. 20 μg m?3 PM1), peaking briefly to >120 μg m?3 (hourly mean) when the ship passed through curtains of higher dust concentrations amassed at the frontal edge of the dust cloud. PM1/PM10 ratios ranged from very low during desert dust intrusions (0.3–0.4) to very high during anthropogenic pollution plume events (0.8–1).  相似文献   

13.

The empirical research on the relationship between corporate environmental responsibility and environmental performance remains in the one-way positive impact and lacks the research on nonlinear relationship between them. Based on the stakeholder theory, this paper selects A-share chemical–listed companies in China from 2006 to 2017 as the research samples and uses generalized method of moments (GMM) model to investigate the impact mechanism between corporate environmental responsibility and environmental performance. The results showed that corporate environmental responsibility positively impacted on environmental performance; however, the impact was not significant. The corporate environmental performance positively and significantly impacted on environmental responsibility. Moreover, results reported that industry competition played a positive regulatory role in corporate environmental responsibility affecting environmental performance and has played a positive role in corporate environmental impact on environmental responsibility. A nonlinear relationship (inverted “U” shape) between environmental responsibility and environmental performance was found. The study results stress to establish a fair and perfect market competition mechanism to improve the environmental performance of chemical industries in China.

  相似文献   

14.
Annual and seasonal trends were discussed for precipitation chemistry in Japan on the basis of a nationwide monitoring network by Japan Environment Agency. For this analysis, 17 sites, selected from the 23 network sites after evaluation of data completeness for the present purpose, were grouped into four areas in terms of the sea which could characterize each area: the Pacific Ocean, the Japan Sea, the Seto Inland Sea and the East China Sea areas. Major ion concentrations at each site were subjected to least-squares multiple regression analysis, and discussion was principally focused on the area-groups. Each area showed significant (p<0.05) decreasing trends in non-sea-salt sulfate (nss-SO42−) concentrations with the annual mean change rate of −3.0% yr−1, whereas no significant trends were detected for NO3 at 59% of the sites. Ammonium (NH4+) showed significant increasing trends for 35%, and decreasing trends for 18% of the sites; and, the maximum change rate of 3.8% yr−1 was recorded in the Pacific Ocean area. Non-sea-salt calcium (nss-Ca2+) concentrations significantly decreased in northern and some industrialized areas. Both the annual cycle-amplitudes and effects of precipitation amounts were significant for the four ions at almost all sites. The maximum concentrations of nss-SO42− and -Ca2+ occurred from winter to spring at most sites. The seasons when the maximum concentrations of NO3 and NH4+ occurred, were found to differ from area to area. Furthermore, the trends in precipitation nss-SO42−, and NO3 were qualitatively consistent with those of anthropogenic emissions of SO2, and NOx in Japan, respectively.  相似文献   

15.
This paper compares the cost-effectiveness of life-saving interventions in Japan, based on information collected from the health, safety and environmental literature. More than 50 life-saving interventions are analyzed. Cost-effectiveness is defined as the cost per life-year saved or as the cost per quality-adjusted life-year saved. Finding a large cost-effectiveness disparity between chemical controls and health care intervention, we raise the question of whether chemical regulations cost society too much. We point out the limitations of this study and propose a way to improve the incorporation of morbidity effects in cost-effectiveness analysis.  相似文献   

16.
Methane (CH4) formation under aerobic conditions has been intensely debated, especially since the discovery of CH4 generation by both dried plant material and living plants. In this study we test the hypothesis that non-microbial CH4 formation also occurs in soils. All lyophilised soil samples investigated under aerobic conditions released CH4 at temperatures ranging from 30 to 70 °C exceeding that allowing normal enzymatic activity to proceed. No emissions were observed for single mineral soil components such as quartz sand, clay mineral and iron oxide. Methane release rates from the soils investigated were found to increase both with increasing temperature and higher organic carbon content. Addition of water to dried soils increased CH4 release rates up to 8-fold those observed with the dried material. Our results suggest the existence of a chemical process in soils that produces CH4 under aerobic conditions, a finding which has not been hitherto reported.  相似文献   

17.
18.
Environmental Science and Pollution Research - In this paper, we analysed the efflorescences present in the frescos of a monumental complex named S. Pietro a Corte situated in the historic centre...  相似文献   

19.
An on-line technique to investigate complex organic oxidation reactions in environmental chamber experiments is presented. The method is based on the direct introduction of the chamber air into an atmospheric pressure ion source of a commercial ion-trap mass spectrometer. To demonstrate the analytical potential of the method (atmospheric pressure chemical ionisation/mass spectrometry, APCI/MS), the ozonolysis of α-pinene was investigated in a series of experiments performed in various sized reaction chambers at atmospheric pressure and 296 K in synthetic air. Investigations were focussed on the influence of the water vapour concentration on the formation of the predominant oxidation product, pinonaldehyde, derived from the α-pinene/ozone reaction. Quantification of pinonaldehyde was achieved by conducting a standard addition technique. The molar yield of pinonaldehyde was found to depend strongly on the actual water vapour concentration between <1 and 80% relative humidity. Starting with an average yield of 0.23±0.05 at dry conditions, pinonaldehyde formation was approximately doubled by reaching a yield of 0.53±0.05 at a relative humidity of around 60%. Furthermore, the formation mechanism of pinonaldehyde was investigated in greater detail using isotopically labelled water. Applying on-line APCI/MS, pinonaldehyde formation under incorporation of 18O was observed, strongly supporting the reaction of the stabilised Criegee radical with water in the gas phase as suggested by Alvarado et al. (Journal of Geophysical Research 103 (1998) 25541–25551). Furthermore, the mass spectra recorded on-line were used to perform a semi-quantitative estimation of the decomposition pathway of the primary ozonide, indicating a branching ratio of 0.35/0.65.  相似文献   

20.
Lemaire J  Croze V  Maier J  Simonnot MO 《Chemosphere》2011,84(9):1181-1187
An industrial coating site in activity located on a chalky plateau, contaminated by BTEX (mainly xylenes, no benzene), is currently remediated by in situ chemical oxidation (ISCO). We present the bench scale study that was conducted to select the most appropriate oxidant. Ozone and catalyzed hydrogen peroxide (Fenton’s reaction) were discarded since they were incompatible with plant activity. Permanganate, activated percarbonate and activated persulfate were tested. Batch experiments were run with groundwater and groundwater-chalk slurries with these three oxidants. Total BTEX degradation in groundwater was reached with all the oxidants. The molar ratios [oxidant]:[Fe2+]:[BTEX] were 100:0:1 with permanganate, 100:100:1 with persulfate and 25:100:1 with percarbonate. Precipitation of either manganese dioxide or iron carbonate (siderite) occurred. The best results with chalk slurries were obtained with permanganate at the molar ratio 110:0:1 and activated persulfate at the molar ratio 110:110:1. To avoid precipitation, persulfate was also used without activation at the molar ratio 140:1. Natural Oxidant Demand measured with both oxidants was lower than 5% of initial oxidant contents. Activated percarbonate was not appropriate because of radical scavenging by carbonated media. Permanganate and persulfate were both effective at oxidant concentrations of ca 1 g kg−1 with permanganate and 1.8 g kg−1 with persulfate and adapted to site conditions. Activation of persulfate was not mandatory. This bench scale study proved that ISCO remediation of a chalky aquifer contaminated by mainly xylenes was possible with permanganate and activated or unactivated persulfate.  相似文献   

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