| 1. |
- Ejlertsson, Jörgen, et al.
(författare)
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Effects of co-disposal of wastes containing organic pollutants with municipal solid waste : a landfill simulation reactor study
- 2003
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Ingår i: Advances in Environmental Research. - 1093-0191 .- 1093-7927. ; 7:4, s. 949-960
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Tidskriftsartikel (refereegranskat)abstract
- Different phases of the life cycle of a landfill receiving municipal solid waste (MSW) were monitored in landfill simulation reactors (LSRs) with the aim of investigating the effects of co-disposal of wastes containing organic pollutants (OPs) with MSW. Two LSRs out of four filled with well-characterised MSW received waste materials containing OPs. These included two types of plasticised PVC flooring materials, freon-blown insulation and phosphorus- and nitrogen-based flame-protected materials. Each of the two LSRs was operated under acid fermentative and neutral methanogenic conditions, respectively as were their corresponding controls, i.e. without extra OP. The methanogenic consortia degrading MSW were hampered by the addition of wastes containing OPs, probably due to the presence of Freon R11 and its degradation product, R21. The concentrations of R11 and R21 ranged between 0.1 and 1800 mg m super(-3) depending on the biogas production rate in the OP-amended LSRs. Losses of butylbenzyl- (26%) and bis(2-ethylhexyl)phthalate (15%) from one of two flooring materials was observed, whereas the other remained unaffected. Methanogenic conditions favoured the loss of plasticisers as compared to acidogenic conditions. Total phosphorus was significantly higher in the OP-spiked LSRs, which indicated a transformation of the non-halogenated flame-retardants.
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| 2. |
- Jonsson, Susanne, 1965-, et al.
(författare)
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Behaviour of mono- and diesters of o-phthalic acid in leachates released during digestion of municipal solid waste under landfill conditions
- 2003
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Ingår i: Advances in Environmental Research. - 1093-0191 .- 1093-7927. ; 7:2, s. 429-440
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Tidskriftsartikel (refereegranskat)abstract
- In order to investigate phthalates in landfill leachates, four landfill simulation reactors, filled with municipal solid waste from a housing area, were studied. Plasticised polyvinyl chloride (PVC) was added to two of the reactors. Two reactors, one with and one without the additional PVC, were aerated for 3 months to achieve methanogenic conditions. The other two became acidogenic a few days after filling and closing. After approximately 3 years, the acidogenic waste became methanogenic. The leachates were analysed for phthalic acid diesters and their degradation products, phthalic acid monoesters and o-phthalic acid. The occurrence of monobenzyl phthalate (MbenzP) and mono(2-ethylhexyl) phthalate (MEHP) showed that the diesters, butylbenzyl phthalate (BBP) and di(2-ethylhexyl) phthalate (DEHP), released from the PVC products had been transformed, and that they were not completely sorbed to particles or to the waste material. Monoesters were observed once methanogenic conditions were established. The monoesters and phthalic acid were present in concentrations several orders of magnitude higher than the diesters themselves. Our results show that it is important to include monoesters in studies of the fate of diesters. To date, monoesters have been neglected in investigations of organic pollutants in landfill leachates.
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| 3. |
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| 4. |
- Xiong, Y, et al.
(författare)
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An experimental investigation of chemical oxygen demand removal from the wastewater containing oxalic acid using three-phase three-dimensional electrode reactor
- 2002
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Ingår i: Advances in Environmental Research. - 1093-0191. ; 7:1, s. 139-145
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Tidskriftsartikel (refereegranskat)abstract
- The removal of chemical oxygen demand (COD) from wastewater containing oxalic acid was experimentally investigated using a three-phase three-dimensional electrode reactor. The experimental results show that the removal efficiency depends on the applied cell voltage, airflow, electrolysis time and the number of repeated runs. The former four factors all had a positive effect while the last factor generally had a negative effect on the COD removal in the experimental range. However, for electrolyses under the conditions of 30.0 V cell voltage, 7.01 min(-1) airflow and 60.0 min, the negative effect was negligible. After 50 runs, the electrochemical reactor could maintain a COD removal efficiency of more than 90%.
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