Search results for " disposal"
showing 3 items of 1293 documents
Effect of temperature on anaerobic treatment of black water in UASB-septic tank systems
2007
The effect of northern European seasonal temperature changes and low temperature on the performance of upflow anaerobic sludge blanket (UASB)-septic tanks treating black water was studied. Three UASB-septic tanks were monitored with different operational parameters and at different temperatures. The results indicated the feasibility of the UASB-septic tank for (pre)treatment of black water at low temperatures with respect to removal of suspended solids and dissolved organic material. Inoculum sludge had little effect on COD(ss) removal, though in the start-up phase some poorly adapted inoculum disintegrated and washed out, thus requiring consideration when designing the process. Removal of …
Particle balance and return loops for microplastics in a tertiary-level wastewater treatment plant.
2021
Highlights: Dewatering by centrifugation was a step that removed a high number of MPs from the sludge. Sludge retained especially the fibrous microplactics. Reject water transported microplastics inside a wastewater treatment plant. Disc filter-based tertiary treatment ensured removal of 99% of microplastics in wastewater. Microplastics (MPs) from households, stormwater, and various industries are transported to wastewater treatment plants (WWTPs), where a high proportion of them are captured before discharging their residuals to watersheds. Although recent studies have indicated that the removed MPs are mainly retained in wastewater sludge, sludge treatment processes have gained less atten…
Socio-technical risk governance through dyadic risk dialogue : copper corrosion as a safety challenge in the geological disposal of spent nuclear fuel
2014
The risk of corrosion in oxygen-free water has become an issue of scientific controversy possibly even threatening the realisation of the final disposal of spent nuclear fuel in Finland and Sweden. In Sweden there has been extensive discussion about the issue since 2007, but only recently has this debate increased in Finland although the similar disposal concept (KBS-3) is applied in both countries. In this report, we analyse how the implementer, Posiva (a Finnish nuclear waste company), and the regulator, STUK (the Finnish Radiation and Nuclear Safety Authority), have been engaged in a dialogue on the risk of copper corrosion. For over thirty years the implementer and regulator have been e…