Effets du pH de la boue et du temps de traitement sur l'élimination électrocinétique de l'aluminium d'une boue de traitement d'eaux potables

Algerian's municipal sewage treatment plants generate around 106 m3 of sewage sludge annually. Recently, rapid expansion of waste water treatment plants without equal attention to the treatment of the produced sludge has generated increasing concerns. While the sludge is usually incinerated or used as an agricultural fertilizer and may contain numerous nutrients, there may also be harmful substances that complicate sludge management. Hence the removal of pollutants from the sludge is necessary before further usage. This paper discusses the characteristics of potable water treatment sludge containing a high aluminum content. Furthermore, an electrokinetic treatment is proposed to remove aluminum from this sludge by varying the type of solution contained in the cathode compartment and modifying the treatment time to optimize the efficiency of the process. Successful results were achieved where 60% of aluminum was collected on the cathode side with a consumed energy around of 1000–2000 kWh kg−1 of sludge weight

The neuropeptide 26RFa in the human gut and pancreas: potential involvement in glucose homeostasis

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Electrokinetic removal of aluminum and chromium from industrial wastewater electrocoagulation treatment sludge

International audienceTreatment of industrial wastewaters by electrocoagulation is very efficient to remove numerous types of pollutant (organic, mineral, colored, metal). However, few researches are devoted to the elimination of metals contained in the generated sludge. The objective of this paper was to study the possible simultaneous removal of aluminum (issued from the electrodes) and chromium (initially present in the effluent) contained in the sludge by electrochemical migration. Electrocoagulation treatment of textile industrial wastewater in which chromium has been added was carried out using aluminum electrodes. Turbidity, COD, and TOC could be efficiently removed with abatement yields, respectively, at 97, 93, and 90%. For chromium, only 62% of the initial amount was eliminated by applying the highest current with a long operating time. The generated sludge contained high amounts of Cr and Al (749 and 1,260 mg/kg of dry sludge), far above the maximum level allowed by legislation. The possibility of removing these pollutants from the resulting sludge using electrokinetic technique was investigated. Acetic acid at 1 or 3 M and citric acid at 3 and 6 M were used as catholyte solutions to enhance the removal of aluminum and chromium (III). Best results for aluminum removal were obtained using 3 M acetic acid: up to 82% of the initial Al was recovered in the cathode chamber, whereas citric acid was more effective in chromium removal: up to 79% was transported to the cathode chamber with 6 M citric acid. Specific energy consumption is also discussed

Neuropeptide 26RFa (QRFP) is a key regulator of glucose homeostasis and its activity is markedly altered in obese/hyperglycemic mice

International audienceRecent studies have shown that the hypothalamic neuropeptide 26RFa regulates glucose homeostasis by acting as an incretin, and increasing insulin sensitivity. In this study, we further characterized the role of the 26RFa/GPR103 peptidergic system in the global regulation of glucose homeostasis using a 26RFa receptor antagonist, and also assessed whether a dysfunction of the 26RFa/GPR103 system occurs in obese hyperglycemic mice. Firstly, we demonstrate that administration of the GPR103 antagonist reduces the global glucose-induced incretin effect and insulin sensitivity whereas, conversely, administration of exogenous 26RFa attenuates glucose-induced hyperglycemia. Using a mouse model of high-fat diet-induced obesity and hyperglycemia, we found a loss of the anti-hyperglcemic effect and insulinotropic activity of 26RFa, accompanied with a marked reduction of its insulin-sensitive effect. Interestingly, this resistance to 26RFa is associated with a down-regulation of the 26RFa receptor in the pancreatic islets, and insulin target tissues. Finally, we observed that the production and release kinetics of 26RFa after an oral glucose challenge is profoundly altered in the high-fat mice. Altogether, the present findings support the view that 26RFa is a key regulator of glucose homeostasis whose activity is markedly altered under obese/hyperglycemic conditions