Reduction of bacteria in storage system of sewage effluents

The present work is aimed to investigate the linear regression model of total coliform (TC), faecal coli-form (FC) and enterococci (ENT) responses in the storage system of sewage effluents at different temperatures (room temperature 25 ± 2 °C, 55 and 65 °C). Five litres (v/v) of sewage effluent samples was stored at room temperature (25 ± 2 °C) for 1, 2, 3 and 4 weeks. In order to investigate the response of bacteria to the storage system at thermal conditions, the sewage samples were stored at the tempera-tures of 55 and 65 °C in a water bath shaker for 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 and 120 min, respectively. The results indicated that the storage system at room tem-perature significantly (p < 0.01) effected the reduction of TC (33%), FC (36.6%) and ENT (47.8%). Moreover, sew-age effluent met WHO guidelines after two weeks of stor-age period at room temperature. The storage system at 55 and 65 °C had more significant influence (p < 0.01) on TC, FC and ENT. The reductions for TC, FC and ENT were 49.6 versus 64, 47.7 versus 83.2% and 47.4 versus 57.3%, respectively. ENT (Gram-positive bacteria) exhibited more resistance to the storage system at 65 °C than TC and FC (both are Gram-negative bacteria). This might be due to the differences in the cell wall structure. It can be concluded that the storage system of sewage effluents has a significant potential for the reduction of indicator bacteria

Bioaugmentation process of secondary effluents for reduction of pathogens, heavy metals and antibiotics

The study probed into reducing faecal indicators and pathogenic bacteria, heavy metals and β-lactam antibiotics, from four types of secondary effluents by bioaugmentation process, which was conducted with Bacillus subtilis strain at 45 'C. As a result, faecal indicators and pathogenic bacteria were reduced due to the effect of thermal treatment process (45 'C), while the removal of heavy metals and β-lactam antibiotics was performed through the functions of bioaccumulation and biodegradation processes of B. subtilis. Faecal coliform met the guidelines outlined by WHO and U. S. EPA standards after 4 and 16 days, respectively. Salmonella spp. and Staphylococcus aureus were reduced to below the detection limits without renewed growth in the final effluents determined by using a culture-based method. Furthermore, 13.5% and 56.1% of cephalexin had been removed, respectively, from secondary effluents containing 1 g of cephalexin L�1 (secondary effluent 3), as well as 1 g of cephalexin L�1 and 10 mg of Ni2 L�1 (secondary effluent 4) after 16 days. The treatment process, eventually, successfully removed 96.6% and 66.3% of Ni2 ions from the secondary effluents containing 10 mg of Ni2 L�1 (secondary effluent 2) and E4, respectively. The bioaugmentation process improved the quality of secondary effluents

The recovery of rare earth metals from WEEE leaching solution via liquid-liquid extraction

The recovery of rare earth metals (REMs) from end-of-life products, such as Waste Electrical and Electronic Equipment (WEEE), is drawing great attention as an attractive strategy for promoting the sustainable development. The hydrometallurgical technique of solvent extraction has been reported to be one of the most interesting method to recover REMs. However, when applied to WEEE, this process is challenged by the heterogeneous composition of electronic waste, completely different from other solid matrices, and it still has much rooms of improvements. This study investigated the extraction, stripping and recovery of REMs from a WEEE leaching solution using Versatic 10 as carrier in the organic phase and oxalic acid as stripping agent. A factorial design was carried out to evaluate the simultaneous effects of factors as the feed phase pH and the concentrations of both extractant and organic phase modifier in the extraction process. Cerium, lanthanum and yttrium were extracted at high percentages using 200 mM of Versatic 10, loaded by 100 mM of TBP in kerosene at pH 7. Moreover, 750 mM of oxalic acid successfully stripped and recovered 7.63 and 13.82 mg/kg of lanthanum and yttrium, respectively

Tilførselsprogrammet 2012. Overvåking av havforsuring av norske farvann

Denne rapporten gjelder undersøkelser av havforsuring som er utført av IMR, NIVA og BCCR på oppdrag fra Klif i 2012. Den er basert på målinger på strekningen Oslo-Kiel og Tromsø-Longyearbyen utført av NIVA, vannsøylemålinger langs faste snitt i Nordsjøen (Torungen – Hirtshals), Norskehavet (Svinøy-NW), og to snitt i Barentshavet (Vardø-N og Fugløya-Bjørnøya) utført av Havforskningsinstituttet, og kontinuerlige overflatemålinger av pCO2 i Norskehavet utført av BCCR i 2012. Resultatene fra Barentshavet viser en klar sesongvariasjon i de øvre 100 m av vannsøylen, som for det meste er styrt av primærproduksjon og ferskvannstilførsel gjennom året. I nordøstlige Barentshavet (Vardø-N) lå metningsgrad for aragonitt (Ar) mellom 1,1 og 2,2 med minimumsverdier i polarvannet ved sørspissen av Svalbard. I tillegg påvirkes karboninnholdet her av polarvannet, spesielt tydelig i den nordlige delen av Barentshavet. Mellom Fugløya og Bjørnøya vistes tydelig sesongvariasjon på grunn av ferskvannstilførsel og primærproduksjon. I Norskehavet var det stor variasjon fra kyst til åpent hav og karboninnholdet påvirkes av kystvannet som brer seg vestover i løpet av sommeren. Konklusjonen er at overflatevann i områdene som er studert i denne rapporten er mettet i forhold til både kalsitt og aragonitt. Laveste metningsgrad ble funnet i polarvannet i nordøstlige Barentshavet. Det er i tillegg viktig å merke seg at metningshorisonten i dyphavet stiger, og per i dag er undermetning av aragonitt påvist på 2400 meters dyp i Norskehavet. Hastigheten av havforsuringen bestemmer når undermetning utvikles både i dyphav og overflaten. Hastigheten for utviklingen vil kunne estimeres nøyaktig først når målinger fra flere år foreligger