| 1. |
- Alverbro, Karin, et al.
(författare)
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A life cycle assessment of destruction of ammunition
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 170:2-3, s. 1101-1109
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Tidskriftsartikel (refereegranskat)abstract
- The Swedish Armed Forces have large stocks of ammunition that were produced at a time when decommissioning was not considered. This ammunition will eventually become obsolete and must be destroyed, preferably with minimal impact on the environment and in a safe way for personnel. The aim of this paper is to make a comparison of the environmental impacts in a life cycle perspective of three different methods of decommissioning/destruction of ammunition, and to identify the environmental advantages and disadvantages of each of these destruction methods: open detonation; static kiln incineration with air pollution control combined with metal recycling, and a combination of incineration with air pollution control, open burning, recovery of some energetic material and metal recycling. Data used are for the specific processes and from established LCA databases. Recycling the materials in the ammunition and minimising the spread of airborne pollutants during incineration were found to be the most important factors affecting the life cycle environmental performance of the compared destruction methods. Open detonation with or without metal recycling proved to be the overall worst alternative from a life cycle perspective. The results for the static kiln and combination treatment indicate that the kind of ammunition and location of the destruction plant might determine the choice of method, since the environmental impacts from these methods are of little difference in the case of this specific grenade. Different methods for destruction of ammunition have previously been discussed from a risk and safety perspective. This is however to our knowledge the first study looking specifically on environmentally aspect in a life cycle perspective.
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| 2. |
- Arshad, Mamoona, et al.
(författare)
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The use of Neem biomass for the biosorption of zinc from aqueous solutions
- 2008
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 1873-3336 .- 0304-3894. ; 157:2-3, s. 534-540
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Tidskriftsartikel (refereegranskat)abstract
- An adsorbent was developed from mature leaves and stem bark of the Neem (Azadirachta indica) tree for removing zinc from water. Adsorption was carried out in a batch process with several different concentrations of zinc by varying pH. The uptake of metal was very fast initially, but gradually slowed down indicating penetration into the interior of the adsorbent particles. The data showed that optimum pH for efficient biosorption of zinc by Neem leaves and stem bark was 4 and 5, respectively. The maximum adsorption capacity showed that the Neem biomass had a mass capacity for zinc (147.08 mg Zn/g for Neem leaves and 137.67 mg Zn/g Neem bark). The experimental results were analyzed in terms of Langmuir and Freundlich isotherms. The adsorption followed pseudo-second-order kinetic model. The thermodynamic assessment of the metal ion-Neem tree biomass system indicated the feasibility and spontaneous nature of the process and Delta G degrees values were evaluated as ranging from -26.84 to -32.75 (Neem leaves) kJ/mol and -26.04 to -29.50 (Neem bark) kJ/mol for zinc biosorption. Due to its outstanding zinc uptake capacity, the Neem tree was proved to be an excellent biomaterial for accumulating zinc from aqueous solutions. (C) 2008 Elsevier B.V. All rights reserved.
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| 3. |
- Augulyte, Lijana, et al.
(författare)
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Multivariate analysis of a biologically activated carbon (BAC) system and its efficiency for removing PAHs and aliphatic hydrocarbons from wastewater polluted with petroleum products
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier. - 0304-3894 .- 1873-3336. ; 170:1, s. 103-110
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Tidskriftsartikel (refereegranskat)abstract
- The efficiency of a biologically activated carbon system for treating wastewater polluted with petroleum products was examined and the effects of process parameters on its efficacy were evaluated. In each experiment 17 alkylated and 19 non-alkylated polycyclic aromatic hydrocarbons (PAHs) and total petroleum hydrocarbons (TPHs, C10-C40) were extracted using semipermeable membrane devices from wastewater before and after treatment. The acquired data during experiments were analyzed using principal component analysis (PCA). The treatment system robustly removed dissolved PAHs across the studied ranges of the process parameters, providing overall removal efficiencies of 96.9-99.7% for the sum of 36 PAHs. However, the major contributor to their removal was sorption rather than biodegradation, and despite the general efficiency of the process there was up to a 9-fold range in the sums of quantified PAHs in the effluents between experiments. Combinations of long process contact time (24 h) with high temperature (24 degrees C) and moderate oxygen concentration (6-7mg O2 L-1) resulted in good removal of bioavailable PAHs. The removal of TPHs was more dependent on biological activities during the wastewater treatment, and consequently more dependent on the process parameters. In addition, small but significant proportions of PAHs were volatilized and released during the wastewater treatment.
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| 4. |
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| 5. |
- Bhatnagar, Amit, et al.
(författare)
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Bromate removal from water by granular ferric hydroxide (GFH)
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 170:1, s. 134-140
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Tidskriftsartikel (refereegranskat)abstract
- The feasibility of granular ferric hydroxide (GFH) for bromate removal from water has been studied. Batch experiments were performed to study the influence of various experimental parameters such as effect of contact time, initial bromate concentration, temperature, pH and effect of competing anions on bromate removal by GFH. The adsorption kinetics indicates that uptake rate of bromate was rapid at the beginning and 75% adsorption was completed in 5 min and equilibrium was achieved within 20 min. The sorption process was well described by pseudo-second-order kinetics. The maximum adsorption potential of GFH for bromate removal was 16.5 mg g−1 at 25 °C. The adsorption data fitted well to the Langmuir model. The increase in OH peak and absence of Br–O bonding in FTIR spectra indicate that ion-exchange was the main mechanism during bromate sorption on GFH. The effects of competing anions and solution pHs (3–9) were negligible. Results of the present study suggest that GFH can be effectively utilized for bromate removal from drinking water.
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| 6. |
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| 7. |
- Blanquez, Paqui, et al.
(författare)
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Continuous biodegradation of 17 beta-estradiol and 17 alpha-ethynylestradiol by Trametes versicolor
- 2008
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 1873-3336 .- 0304-3894. ; 150:2, s. 459-462
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Tidskriftsartikel (refereegranskat)abstract
- The feasibility of 17 beta-estradiol (E2) and 17 alpha-ethynylestradiol (EE2) removal by Trametes versicolor was demonstrated in batch and continuous cultures. In batch, E2 and EE2 initially supplied at 10 mg l(-1) were removed by more than 97% in 24 h, which corresponded to volumetric removal rates of 0.43 and 0.44 mg l(-1) h(-1), respectively. A bioreactor inoculated with T versicolor pellets was then continuously operated during 26 days at a hydraulic retention time of 120 h. E2 and EE2 were completely removed at volumetric removal rates of 0.16 and 0.09 mg l(-1) h(-1), respectively, when fed at 18.8 and 7.3 mg l(-1), respectively. Evidence was found that removal was caused by laccase. This study demonstrates the technical feasibility of fungal treatment of estrogens using continuous bioreactor with suspended fungal biomass.
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| 8. |
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| 9. |
- Elgh-Dalgren, Kristin, 1980-, et al.
(författare)
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Laboratory and pilot scale soil washing of PAH and arsenic from a wood preservation site : Changes in concentration and toxicity
- 2009
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Ingår i: Journal of Hazardous Materials. - Amsterdam : Elsevier. - 0304-3894 .- 1873-3336. ; 172:2-3, s. 1033-1040
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Tidskriftsartikel (refereegranskat)abstract
- Soil washing of a soil with a mixture of both polycyclic aromatic hydrocarbons (PAH) and As was evaluated in laboratory and pilot scale, utilizing both single and mixtures of different additives. The highest level of decontamination was achieved with a combination of 0.213 M of the chelating agent MGDA and 3.2xCMC* of a nonionic, alkyl glucoside surfactant at pH 12 (Ca(OH)2). This combination managed to reach Swedish threshold values within 10 min of treatment when performed at elevated temperature (50°C), with initial contaminant concentrations of As = 105±4 mg/kg and US-EPA PAH16 = 46.0±2.3 mg/kg. The main mechanisms behind the removal were the pH-effect for As and a combination of SOM-ionization as a result of high pH and micellar solubilization for PAHs. Implementation of the laboratory results utilizing a pilot scale equipment did not improve the performance, which may be due to the shorter contact time between the washing solution and the particles, or changes in physical characteristics of the leaching solution due to the elevated pressure utilized. The ecotoxicological evaluation, Microtox®, demonstrated that all soil washing treatments increased the toxicity of soil leachates, possibly due to increased availability of contaminants and toxicity of soil washing solutions to the test organism.
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| 10. |
- Eriksson, Eva, 1973-, et al.
(författare)
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Substance flow analysis of parabens in Denmark complemented with a survey of presence and frequency in various commodities
- 2008
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 156:1-3, s. 240-259
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Tidskriftsartikel (refereegranskat)abstract
- Parabens are commonly used as preservatives due to anti-bactericidal and anti-fungicidal properties and they are ubiquitously present in personal care products, pharmaceuticals, food, industrial and domestic commodities. They are suspected of causing endocrine disrupting effects to aquatic organisms and adverse effects in humans and, thus, it is highly relevant to identify and quantify their sources and transportation pathways in the urban environment. Here a substance flow analysis (SFA) was performed in order to map and comprehend the substances’ flow on a national basis. Many household commodities were found to contain parabens; cleaning detergents, slimy toys, and water-based paint. The presence and concentration of parabens are regulated in cosmetics and food. Use of parabens in pharmaceuticals as excipients is documented in Denmark. The import of parabens is increasing; although the number of industrial parabens containing commodities is decreasing and manufacturer reports phase-out of parabens. The vast majority of the paraben containing commodities has a durability of 18–30 months, thus the average lifetime of the paraben stock is perceived to be limited. The inflow was ca. 154 tonnes via pure chemicals and 7.2–73 tonnes via commodities in 2004. This corresponds to an average wastewater concentration of 640–900 μg/L, when excluding discharge to solid waste, soil, biodegradation and metabolism. This is in the same order of magnitudes as can be found in industrial wastewater but higher than that seen in domestic wastewater. The data needed for the SFA is sparse, dispersed, and difficult to access and associated with a great deal of uncertainty.
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| 11. |
- Farajzadeh, Mir Ali, et al.
(författare)
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Optimization and application of homogeneous liquid-liquid extraction in preconcentration of copper (II) in a ternary solvent system
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 1873-3336 .- 0304-3894. ; 161:2-3, s. 1535-1543
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Tidskriftsartikel (refereegranskat)abstract
- In this study a homogeneous liquid-liquid extraction based on the Ph-dependent phase-separation process was investigated using a ternary solvent system (water-acetic acid-chloroform) for the preconcentration of Cu2+ ions. 8-Hydroxy quinoline was used as the chelating agent prior to its extraction. Flame atomic absorption spectro photometry using acetylene-air flame was used for the quantitation of analyte after preconcentration. The effect of various experimental parameters in extraction step was investigated using two optimization methods, one variable at a time and central composite design. The experimental design was done at five levels of operating parameters. Nearly the same optimized results were obtained using both methods: sample size, 5 mL: volume of NaOH 10 M, 2 mL; chloroform volume, 300 mu L; 8-hydroxy quinoline concentration more than 0.01 M and Salt amount did not affect the extraction significantly. Under the optimum conditions the calibration graph was linear over the range 10-2000 mu g L-1. The relative standard deviation was 7.6% for six repeated determinations (C = 500 mu g L-1). Furthermore, the limit of detection (S/N = 3) and limit of quantification (S/N = 10) of the method were obtained as 1.74 and 6 mu g L-1, respectively. (C) 2008 Elsevier B.V. All rights reserved.
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| 12. |
- Fernández-Álvarez, Paula, et al.
(författare)
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Removal and destruction of endocrine disrupting contaminants by adsorption with molecularly imprinted polymers followed by simultaneous extraction and phototreatment.
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 1873-3336 .- 0304-3894. ; 163, s. 1107-1112
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Tidskriftsartikel (refereegranskat)abstract
- This study presents a method to regenerate molecularly imprinted polymers (MIPs) used for the selective removal of endocrine disrupting compounds from aqueous effluents. Regeneration was based on solvent extraction under UV irradiation to regenerate the polymer and the solvent while destroying the contaminants. Acetone was selected as the best solvent for irradiation of estrone (E1), 17beta-estradiol (E2) and ethinylestradiol (EE2) using either UVC (254nm) or UV-vis. A MIP synthesized with E2 as template was then tested for the extraction of this compound from a 2mug/L loaded aqueous solution. E2 was recovered by 73+/-11% and 46+/-13% from the MIPs and a non-imprinted control polymer synthesized under the same conditions, respectively, after a single step elution with acetone. The irradiated polymers and acetone were reused for an additional extraction-regeneration cycle and showed no capacity decrease.
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| 13. |
- Filipsson, Monika, et al.
(författare)
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Exposure to contaminated sediments during recreational activities at a public bathing place
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier. - 0304-3894 .- 1873-3336. ; 171:1-3, s. 200-207
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Tidskriftsartikel (refereegranskat)abstract
- More and more time is spent on recreational activities, but few risk assessments focus specifically on these situations and exposure factor data are often scarce. To assess exposure to contaminants at a public bathing place in an urban environment, we have compiled literature data, conducted observation studies, and analyzed water and sediment samples. The levels of anthropogenic contaminants are high in urban environments and traffic frequently plays an important role. In this study, to characterize variability and uncertainty, the deterministic exposure calculations for metal pollutants were supplemented by a probability bounds analysis for the polycyclic aromatic hydrocarbons (PAH). The results from these calculations show that oral intake is the major exposure route for metals, while skin absorption, with present assumptions, is more important for the PAH. The presently measured levels of contaminants, at this public bathing place, cannot be anticipated to cause any significant adverse influence on public health.
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| 14. |
- Flyhammar, Peter, et al.
(författare)
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Leaching of different elements from subbase layers of alternative aggregates in pavement constructions
- 2006
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 1873-3336 .- 0304-3894. ; 137:1, s. 603-611
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to analyze the accumulated effects of leaching in two test roads were municipal solid waste incineration (MSWI) bottom ash and aggregate from a railway embankment, respectively, were used as subbase aggregates. Solid samples from the subbase and the subgrade were collected in trenches, which were excavated perpendicular to the road extension. The samples were analyzed with respect to pH, water content, electrical conductivity and extractable fractions of macro and trace constituents. To conclude, spatial distribution patterns of different constituents in subbase and subgrade layers confirms the existence of two major transport processes in a road with permeable shoulders: diffusion underneath surface asphalt layers driven by a concentration gradient directed horizontally towards the shoulder of the road where the dissolved elements are carried away by advection. (c) 2006 Elsevier B.V. All rights reserved.
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| 15. |
- Gahan, Chandra Sekhar, et al.
(författare)
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A study on the toxic effects of chloride on the biooxidation efficiency of pyrite
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 172:2-3, s. 1273-1281
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Tidskriftsartikel (refereegranskat)abstract
- Bioleaching operations in areas with limited chloride-free water and use of ashes and dust as neutralizing agents have motivated to study the chloride toxicity and tolerance level of the microorganisms. Biooxidation of pyrite using chloride containing waste ash compared with Ca(OH)2 + NaCl as neutralizing agent was investigated to evaluate the causes of low pyrite oxidation. Both precipitation of jarosite as well as the toxic effect of chloride on the microorganisms were responsible for lower pyrite recoveries. Another study with sudden exposure of chloride during pyrite biooxidation, addition of 4 g/L was lethal for the microorganisms. Addition of 2 g/L chloride resulted in precipitation of jarosite with slightly lower pyrite recovery whereas the addition of 3 g/L chloride temporarily chocked the microorganisms but activity was regained after a short period of adaptation. Population dynamics study conducted on the experiment with 3 g/L chloride surprisingly showed that Leptospirillum ferriphilum, which was dominating in the inoculum, completely disappeared from the culture already before chloride was added. Sulphobacillus sp. was responsible for iron oxidation in the experiment. Both Acidithiobacillus caldus and Sulphobacillus sp. were adaptive and robust in nature and their numbers were slightly affected after chloride addition. Therefore, it was concluded that the microbial species involved in the biooxidation of pyrite vary in population during the different stages of biooxidation.
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| 16. |
- Gustavsson, Björn, et al.
(författare)
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Comparison of analytical error and sampling error for contaminated soil
- 2006
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 138:2, s. 252-260
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Tidskriftsartikel (refereegranskat)abstract
- Investigation of soil from contaminated sites requires several sample handling steps that, most likely, will induce uncertainties in the sample. The theory of sampling describes seven sampling errors that can be calculated, estimated or discussed in order to get an idea of the size of the sampling uncertainties. With the aim of comparing the size of the analytical error to the total sampling error, these seven errors were applied, estimated and discussed, to a case study of a contaminated site. The manageable errors were summarized, showing a range of three orders of magnitudes between the examples. The comparisons show that the quotient between the total sampling error and the analytical error is larger than 20 in most calculation examples. Exceptions were samples taken in hot spots, where some components of the total sampling error get small and the analytical error gets large in comparison. Low concentration of contaminant, small extracted sample size and large particles in the sample contribute to the extent of uncertainty.
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| 17. |
- Haque, Nazmul, et al.
(författare)
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Characteristics of arsenic adsorption to sorghum biomass
- 2007
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 1873-3336 .- 0304-3894. ; 145:1-2, s. 30-35
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Tidskriftsartikel (refereegranskat)abstract
- The development of efficient and economic new adsorbent materials for the removal of arsenic from groundwater is a priority in regions where human health is directly affected by elevated arsenic concentrations. Adsorption of arsenic on sorghum biomass (SB) was investigated for the removal of arsenic from aqueous solutions. Potentiometric titrations and FTIR analysis evidenced two potential binding sites associated with carboxyl and hydroxyl groups. Batch experiments were carried out to determine the equilibrium time for arsenic adsorption to SB. The effect of pH on arsenic adsorption to SB was investigated for a pH range of 2.0-10.0. A strong influence of pH was demonstrated with a maximum removal of arsenic at pH 5.0. Freundlich and Langmuir isotherms were applied to equilibrium data. The Freundlich model fitted the equilibrium data and provided evidence for site heterogeneity at the binding surface. Column experiments were performed to obtain the breakthrough curves for both non-immobilized sorghum biomass and immobilized sorghum biomass.
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| 18. |
- Jonsson, Lage T. I., 1949-, et al.
(författare)
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Aspects of particulate dry deposition in the urban environment
- 2008
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 153:1-2, s. 229-243
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Tidskriftsartikel (refereegranskat)abstract
- Micro-scale deposition models, typically used for pipes, were adapted to outdoor situations and combined with computational fluid dynamics (CFD) calculations of flow conditions in order to study the fine structure of the deposition velocity on ground, walls, and roofs in an urban environment. Several deposition modeling techniques taken from the literature were used for the predictions. The urban geometry was represented by two different blocks of houses, which together with two wind directions gave four different cases to study. The calculations show large local variations of the deposition velocity resulting in a pattern similar to the variation of the friction velocity. This demonstrates the strong dependence of the deposition velocity on the friction velocity. Further alteration of the deposition velocity is caused by the variation of the micro-scale roughness and different surface temperatures. The results presented provide some guidance for where to look for hotspots of deposited material and also show that a representation of the deposition velocity in a city by only one or just a few values is a great simplification locally and could lead to serious mistakes.
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| 19. |
- Jonsson, Lage, 1949-, et al.
(författare)
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Toxic gas clouds : Effects and implications of dry deposition onconcentration
- 2005
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 124:1-3, s. 1-18
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Tidskriftsartikel (refereegranskat)abstract
- The influence of the dry deposition process on concentration pertaining to toxic gas clouds was investigated by model calculations. Three main release scenarios were simulated, with nine micrometeorological cases considered for each. To compare and confirm the results, two model types, a stochastic particle model and a box-type model, were independently used to simulate many of the different cases. The results showed that the effects of dry deposition may be strong for releases at, or confined close to the ground, e.g. neutral or unstable stratification can cause higher concentrations than stable stratification after 10–15 km. Risk distances are in turn affected and may be substantially shortened, e.g. for a zero-height release like that from an evaporating pool, a 50% reduction in total airborne substance may occur within 500 m at a low wind velocity and neutral or stable stratification
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| 20. |
- Jonsson, Sofia, 1973-, et al.
(författare)
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Degradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soils by Fenton's reagent : a multivariate evaluation of the importance of soil characteristics and PAH properties
- 2007
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 149:1, s. 86-96
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we investigated how the chemical degradability of polycyclic aromatic hydrocarbons (PAHs) in aged soil samples from various contaminated sites is influenced by soil characteristics and by PAH physico-chemical properties. The results were evaluated using the multivariate statistical tool, partial least squares projections to latent structures (PLS). The PAH-contaminated soil samples were characterised (by pH, conductivity, organic matter content, oxide content, particle size, specific surface area, and the time elapsed since the contamination events, i.e. age), and subjected to relatively mild, slurry-phase Fenton's reaction conditions. In general, low molecular weight PAHs were degraded to a greater extent than large, highly hydrophobic variants. Anthracene, benzo(a)pyrene, and pyrene were more susceptible to degradation than other, structurally similar, PAHs; an effect attributed to the known susceptibility of these compounds to reactions with hydroxyl radicals. The presence of organic matter and the specific surface area of the soil were clearly negatively correlated with the degradation of bi- and tri-cyclic PAHs, whereas the amount of degraded organic matter correlated positively with the degradation of PAHs with five or six fused rings. This was explained by enhanced availability of the larger PAHs, which were released from the organic matter as it degraded. Our study shows that sorption of PAHs is influenced by a combination of soil characteristics and physico-chemical properties of individual PAHs. Multivariate statistical tools have great potential for assessing the relative importance of these parameters.
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| 21. |
- Kalmykova, Yuliya, 1981, et al.
(författare)
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Adsorption of Cd, Cu, Ni, Pb, and Zn on Sphagnum peat from solutions with low concentrations
- 2007
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 1873-3336 .- 0304-3894. ; 152:152, s. 885-891
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Tidskriftsartikel (refereegranskat)abstract
- This work investigates adsorption of metal ions on Sphagnum peat from solutions with environmentally relevant concentrations of metals. The peat moss is intended as an alternative, low-cost filter material for contaminated waters. Adsorption of Cd, Cu, Ni, Pb and Zn was studied in batch tests, and adsorption isotherms were determined. The kinetics of adsorption was analyzed using a second-order model and rate constants were calculated. An empirical model for predicting adsorption of metal ions at a given time was derived from these constants. Metal ions were removed in the descending order Pb > Cu > Ni > Cd > Zn. Relationship between the affinities of the metals to the peat active sites with chemical properties for the metals were indicated by the results. In addition, equilibration studies were performed at constant pH and ionic strength. The experimental data fitted the Freundlich equation. Both the uptake of metals and the Freundlich constants increased in line with increasing pH. The Freundlich exponent declined with higher initial concentrations, suggesting adsorption to sites with lower activity.
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| 22. |
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| 23. |
- Kantarelis, E., et al.
(författare)
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Sustainable valorization of plastic wastes for energy with environmental safety via High-Temperature Pyrolysis (HTP) and High-Temperature Steam Gasification (HTSG)
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 167:1-3, s. 675-684
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Tidskriftsartikel (refereegranskat)abstract
- In the present study the energetic valorization of electric cable shredder residues (mixed plastics) has been investigated. Thermochemical conversion by means of High-Temperature Steam Gasification (HTSG) and High-Temperature Pyrolysis (HTP) was studied. The effects of temperature and reaction time - process parameters - were investigated. Comparison of the results showed that HTSG seems a more suitable process in terms of produced syngas quality (64%. v/v and 13 MJ/Nm(3)) than HTP because of higher H-2 yield and lower tar content.
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| 24. |
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| 25. |
- Larsson, D. G. Joakim, 1969, et al.
(författare)
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Effluent from drug manufactures contains extremely high levels of pharmaceuticals.
- 2007
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Ingår i: Journal of hazardous materials. - : Elsevier BV. - 0304-3894. ; 148:3, s. 751-5
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Tidskriftsartikel (refereegranskat)abstract
- It is generally accepted that the main route for human pharmaceuticals to the aquatic environment is via sewage treatment plants receiving wastewater from households and hospitals. We have analysed pharmaceuticals in the effluent from a wastewater treatment plant serving about 90 bulk drug manufacturers in Patancheru, near Hyderabad, India--a major production site of generic drugs for the world market. The samples contained by far the highest levels of pharmaceuticals reported in any effluent. The high levels of several broad-spectrum antibiotics raise concerns about resistance development. The concentration of the most abundant drug, ciprofloxacin (up to 31,000 microg/L) exceeds levels toxic to some bacteria by over 1000-fold. The results from the present study call for an increased focus on the potential release of active pharmaceutical ingredients from production facilities in different regions.
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| 26. |
- Menad, Nourreddine
(författare)
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Recycling of auto shredder residue
- 2007
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 139:3, s. 481-490
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Tidskriftsartikel (refereegranskat)abstract
- Currently, about 75% of end-of-life vehicle's (ELV) total weight is recycled in EU countries. The remaining 25%, which is called auto shredder residues (ASR) or auto fluff, is disposed of as landfill because of its complexity. It is a major challenge to reduce this percentage of obsolete cars. The European draft directive states that by the year 2006, only 15% of the vehicle's weight can be disposed of at landfill sites and by 2015, this will be reduced to 5%. The draft directive states that a further 10% can be incinerated. The quantities of shredder fluff are likely to increase in the coming years. This is because of the growing number of cars being scrapped, coupled with the increase in the amount of plastics used in cars. In Sweden, some current projects are focusing on recycling of ASR material. In this paper some different alternatives for using this material are reported. The hypothetical injection of ASR into a blast furnace concentrating on ASR's effect to some blast furnace (BF) parameters has been completed using a blast furnace mass balance model. As a result, in principle, ASR can be used as reducing agent in the BF process if certain conditions are met. The particle size of ASR material must be controlled to ensure optimal gasification of the material in the raceway. Regarding the chemical composition of ASR, the non-ferrous content can affect the pig iron quality, which is difficult to rectify at a later point. The most attractive recycling alternative is to use the products obtained from pyrolysis of ASR in appropriate metallurgical processes.
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| 27. |
- Munoz, Raul, et al.
(författare)
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Biofilm photobioreactors for the treatment of industrial wastewaters.
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 1873-3336 .- 0304-3894. ; 161:1, s. 29-34
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Tidskriftsartikel (refereegranskat)abstract
- A flat plate and a tubular packed-bed photobioreactor with an algal-bacterial biofilm attached onto Poraver((R)) beads carriers, a flat plate and a tubular photobioreactor with the biofilm attached onto the reactor walls, and an algal-turf reactor were compared in terms of BOD removal efficiencies, elimination capacities, and stability. A control column photobioreactor with suspended algal-bacterial biomass was also tested to compare the performance of biofilm photobioreactors with conventional algal-based processes. When the algal-bacterial biomass was immobilized onto Poraver((R)) the process never reached a steady state due to a poor homogenization in the bioreactor. When the biofilm was formed onto the reactor wall (or reactor base) the process was stable. A maximum degradation rate of 295mg BODl(-1)h(-1) was achieved in the algal-turf reactor although control experiments performed in the dark showed atmospheric O(2) diffusion represented 55% of the oxygenation capacity in this system. BOD removal rates of 108, and 92mg BODl(-1)h(-1) were achieved in the tubular and flat plate biofilm reactors, respectively, compared to 77mg BODl(-1)h(-1) in the control suspended bioreactor. In addition, all biofilm photobioreactors produced an easily settleable biomass. Evidence was found that biomass attachment to the reactor's wall improved stability.
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| 28. |
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| 29. |
- Renman, Agnieszka, et al.
(författare)
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Metal removal by bed filter materials used in domestic wastewater treatment
- 2009
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 166:2-3, s. 734-739
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Tidskriftsartikel (refereegranskat)abstract
- Bed filters using reactive materials are an emerging technology for on-site wastewater treatment. Used materials, which are enriched with phosphorus, can be used as a fertiliser or soil amendment. However the materials can also be enriched with metals from the wastewater. Six materials (opoka, sand, Polonite (R), limestone, two types of blast furnace slag) exposed to long-term wastewater loading in columns and in a compact filter well filled with Polonite were investigated for metal removal and accumulation. Wastewater applied to the columns had low heavy metal concentrations in the order Zn > Cu > Mn > Ni > Cr. All columns were able to remove 53%-83% of Zn except those filled with sand. Polonite demonstrated a high removal capacity of Mn (>98%), while only the slag materials were able to remove Ni. All materials showed increased Cu, Cr(III). Mn. Pb and Zn content after filtration. Speciation calculations showed that high concentrations of dissolved organic matter might have prevented efficient metal removal, particularly in the case of Cu. The low content of toxic heavy metals in the studied filter materials studied would probably not restrict their use as a fertiliser or soil amendment.
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| 30. |
- Ribé, Veronica, et al.
(författare)
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Leaching of contaminants from untreated pine bark in a batch study : Chemical analysis and ecotoxicological evaluation
- 2009
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Ingår i: Journal of Hazardous Materials. - Amsterdam : Elsevier. - 0304-3894 .- 1873-3336. ; 163:2-3, s. 1096-1100
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Tidskriftsartikel (refereegranskat)abstract
- Low cost sorbents have been widely studied in recent years in the search for filter materials that retain contaminants from water. One promising, low cost material is pine bark, a by-product from the forest industry. Many studies have shown that pine bark has great potential for the treatment of metals and organic substances, as a replacement for other commercial sorbents such as active carbon. However, some potential problems are introduced through the use of natural materials and by-products. One such problem that must be addressed is the possibility of leaching of contaminants from the filter material, especially in the initial filtration step or during flushes of lightly contaminated water, e.g. during rainfall for on-site treatment of storm water or landfill leachate. The aim of this preliminary study was therefore to identify potential risks and limitations of using pine bark as a filter material. Leachate from a standardized batch test was analysed for metals, dissolved organic carbon (DOC) and phenols. In addition to these chemical analyses, an ecotoxicological test was conducted using the test organism Daphnia magna. The results showed significant leaching of DOC and some metals. Only a small fraction of the DOC was present as phenols. The leachate was however found to be toxic to the test organism without pH adjustment, and the EC50 was established at an approximate leachate concentration of 40%. This was concluded to be related to the low pH in the eluate, since no toxicity was observed after pH adjustment before the toxicity tests. © 2008 Elsevier B.V. All rights reserved.
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| 31. |
- Scott Andersson, Åsa, et al.
(författare)
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A method to relate chemical accident properties and expert judgements in order to derive useful information for the development of Environment-Accident Index.
- 2007
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894. ; 147, s. 524-33
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Tidskriftsartikel (refereegranskat)abstract
- The environment consists of a variety of different compartments and processes that act together in a complex system that complicate the environmental risk assessment after a chemical accident. The Environment-Accident Index (EAI) is an example of a tool based on a strategy to join the properties of a chemical with site-specific properties to facilitate this assessment and to be used in the planning process. In the development of the EAI it is necessary to make an unbiased judgement of relevant variables to include in the formula and to estimate their relative importance. The development of EAI has so far included the assimilation of chemical accidents, selection of a representative set of chemical accidents, and response values (representing effects in the environment after a chemical accident) have been developed by means of an expert panel. The developed responses were then related to the chemical and site-specific properties, through a mathematical model based on multivariate modelling (PLS), to create an improved EAI model. This resulted in EAInew, a PLS based EAI model connected to a new classification scale. The advantages of EAInew compared to the old EAI (EAIold) is that it can be calculated without the use of tables, it can estimate the effects for all included responses and make a rough classification of chemical accidents according to the new classification scale. Finally EAInew is a more stable model than EAIold, built on a valid base of accident scenarios which makes it more reliable to use for a variety of chemicals and situations as it covers a broader spectra of accident scenarios. EAInew can be expressed as a regression model to facilitate the calculation of the index for persons that do not have access to PLS. Future work can be; an external validation of EAInew; to complete the formula structure; to adjust the classification scale; and to make a real life evaluation of EAInew.
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| 32. |
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| 33. |
- Svensson, Margareta, et al.
(författare)
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Diffusion tests of mercury through concrete, bentonite-enhanced sand and sand
- 2007
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 142:1-2, s. 463-467
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Tidskriftsartikel (refereegranskat)abstract
- The transport by diffusion of Hg(II) and Hg(O) through a barrier of concrete or bentonite-enhanced sand was examined under aerobic conditions. Sand was used as a reference system parallel to the two systems. Speciation of mercury was performed with a purge and trap method, where dissolved Hg(O) was purged with nitrogen gas from the sample, through a trap for volatile oxidized mercury species and finally trapped in an oxidative solution. The apparent diffusion coefficient (from Fick's second law of diffusion) for oxidized mercury was 1 x 10(-14) m(2)/s in Standard Portland concrete and 4 x 10(-13) m(2)/s in quartz sand. The diffusion of Hg(O) seemed to be faster than for Hg(II), Hg(O) was however oxidized to Hg(H) under aerobic conditions, and after 45 months only 1-10% of the total mercury concentration was Hg(O). (c) 2006 Elsevier B.V. All rights reserved.
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| 34. |
- Svensson, Margareta, et al.
(författare)
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Formation of cinnabar : estimation of favourable conditions in a proposed Swedish repository
- 2006
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Ingår i: Journal of Hazardous Materials. - Amsterdam : Elsevier. - 0304-3894 .- 1873-3336. ; 136:3, s. 830-836
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Tidskriftsartikel (refereegranskat)abstract
- A deep repository for permanent storage of mercury will be designed and built in Sweden. The preferred chemical state for mercury in such a repository would be the sulphide HgS (cinnabar), which is a highly insoluble and the dominating natural mercury mineral. The possible formation of HgS from HgO or Hg(0) by reaction with a sulphur source (S, FeS or FeS2) is discussed from thermodynamic considerations, and pe–pH-diagrams are constructed by using the computer code MEDUSA to illustrate under which conditions HgS would dominate. Calculations of the speciation (PHREEQE) under varying conditions (S/Hg-ratios, presence of chloride) are given. Long-term laboratory experiments are performed, where the formation of HgS from the basic components is demonstrated (after mixing under various conditions and storage at room temperature for up to 3 years). The feasibility of HgS-formation with time in a geologic repository under conditions representative of deep granitic bedrock (calcium-bicarbonate buffered to pH 7–8.5) is discussed, as well as effects of alkaline conditions (concrete environment, pH 10.5–12.5). Formation of soluble polysulphides is not expected as long as the S/Hg mole ratio is within 1–1.3 and pH is below 10.5–11. Concrete should be used with caution. Suitable ballast materials could be introduced that would reduce porewater-pH that otherwise would be above 12.
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| 35. |
- Svensson, Malin, et al.
(författare)
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The effect of isosaccharinic acid (ISA) on the mobilization of metals in municipal solid waste incineration (MSWI) dry scrubber residue
- 2007
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 144:1-2, s. 477-484
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Tidskriftsartikel (refereegranskat)abstract
- Co-landfilling of incineration ash and cellulose might facilitate the alkaline degradation of cellulose. A major degradation product is isosaccharinic acid (ISA), a complexing agent for metals. The impact of ISA on the mobility of Pb, Zn, Cr, Cu and Cd from a municipal solid waste incineration dry scrubber residue was studied at laboratory using a reduced 25-1 factorial design. Factors investigated were the amount of calcium isosaccharinate (Ca(ISA)2), L/S ratio, temperature, contact time and type of atmosphere (N2, air, O2). The effects of pH and Ca(ISA)2 as well as other factors on the leaching of metals were quantified and modelled using multiple linear regression (α = 0.05). Cd was excluded from the study since the concentrations were below the detection limit. The presence of Ca(ISA)2 resulted in a higher leaching of Cu indicating complex formation. Ca(ISA)2 alone had no effect on the leaching of Pb, Zn and Cr. A secondary effect on the mobilization was predicted to occur since Ca(ISA)2 had a positive effect on the pH and the leaching of Pb, Zn and Cr increased with increasing pH. The leaching of Pb varied from 24 up to 66 wt.% of the total Pb amount (1.74 ± 0.02 g(kg TS)-1) in the dry scrubber residue. The corresponding interval for Zn (7.29 ± 0.07 g(kg TS)-1) and Cu (0.50 ± 0.02 g(kg TS)-1) were 0.5-14 wt.% of Zn and 0.8-70 wt.% of Cu. Maximum leaching of Cr (0.23 ± 0.03 g(kg TS)-1) was 4.0 wt.%. At conditions similar to a compacted and covered landfill (4 °C, 7 days, 0 vol.% O2) the presence of ISA can increase the leaching of Cu from 2 to 46 wt.% if the amount of cellulose-based waste increases 20 times, from the ratio 1:100 to 1:5. As well, the leaching of Pb, Zn, and Cr can increase from 32 to 54 wt.% (Pb), 0.8-8.0 wt.% (Zn), and 0.5 to 4.0 wt.% (Cr) depending on the amount of cellulose and L/S ratio and pH value. Therefore, a risk (α = 0.05) exists that higher amounts of metals are leached from landfills where cellulose-containing waste and ash are co-disposed. This corresponds to an additional 29 t of Pb and 17 t of Cu leached annually from a compacted and covered landfill in the north of Sweden.
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| 36. |
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