| 1. |
- Björkqvist, Susan, 1967, et al.
(författare)
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Hydrocarbons in biogas from household solid waste
- 1998
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Ingår i: Environmental Technology (United Kingdom). - 1479-487X .- 0959-3330. ; 19:6, s. 639-642
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Tidskriftsartikel (refereegranskat)abstract
- The components of biogas from source-separated domestic waste were studied for the first major Swedish plant (Sobacken, Boras) in operation. Methane, carbon dioxide and C-6-C-11 hydrocarbons were determined by gas chromatographic methods. The content of methane was found to be just over 70% (v/v). The major polluting hydrocarbon in the biogas was p-cymene. It may be formed by rearrangement and dehydrogenation of limonene and other monoterpenes in food waste.
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| 2. |
- Johansson, Lena, 1967-
(författare)
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Industrial by-products and natural substrata as phosphorus sorbents
- 1999
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Ingår i: Environmental technology. - : Informa UK Limited. - 0959-3330 .- 1479-487X. ; 20:3, s. 309-316
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Tidskriftsartikel (refereegranskat)abstract
- The efficiency of phosphorus (P) removal in ecologically-engineered wastewater treatment facilities, such as artificial wetlands and sand filters, can be improved by using a reactive sorbent. The sorbent must therefore have a high P-sorption capacity and an adequate hydraulic conductivity. Several filter materials have been tested here in regard to their P-sorption capacity. In this study, three natural materials - opoka (a bedrock found in south-eastern Poland) limestone and the B horizon of a forest soil, plus two artificial materials - blast furnace slag (crystalline and amorphous, in two particle sizes (0-0.125 mm and 0.25-4 mm), and fly ash were investigated. Phosphate sorption and isotherm studies were performed. In addition, physical and chemical properties of the materials were also investigated. The P-sorption experiment showed that all materials were capable of sorbing P to various extents. The coarse crystalline slag had the highest P-sorption capacity followed in order by the fine crystalline slag, the fine amorphous slag, the B horizon, the limestone, the coarse amorphous slag, the ash and the opoka. The isotherm studies showed that the B horizon was the most efficient P retainer, followed in order by the coarse crystalline slag, the fine crystalline slag, the fine amorphous slag and the coarse amorphous slag, with opoka and limestone showing the poorest retention. It was concluded that the crystalline slags had the highest P-sorption capacities, and that coarse crystalline slag possessed the highest hydraulic conductivity, suggesting that this material is the most suitable for use in ecological wastewater treatment systems.
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| 3. |
- Sulzbacher, K., et al.
(författare)
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Anaerobic reduction of hexavalent chromium in filter sludge of an electrochemical process
- 1997
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Ingår i: Environmental technology. - : Informa UK Limited. - 0959-3330 .- 1479-487X. ; 18:3, s. 301-307
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Tidskriftsartikel (refereegranskat)abstract
- The potential of an anaerobic system to remediate hexavalent chromium containing waste was investigated. Experiments were performed at laboratory scale in the batch mode. The variables studied were the concentrations of waste, of inoculum, of yeast as an additional carbon source, of sulfate and the initial pH. The gas development, the final pH and the final concentrations of hexavalent and total chromium were measured. The evaluation was based on Multivariate data analysis. It could be shown that a remediation is possible. The influence of pH and sulfate were negligible in the given range. High yeast concentrations and low waste concentrations were favorable for a strong gas development and a complete elimination of chromate. Possible mechanisms are the active reduction of chromate by the microorganisms, its use as electron acceptor in bacterial respiration, and its sorption on organic material. Especially the last explanation is strongly supported by the experiments.
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| 4. |
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