The use of microcalorimetry to compare the biological activity of a CAS and a MBR sludge—application to pharmaceutical active compounds

Abstract

Micropollutants removal, such as pharmaceutical substances, during wastewater treatment processes is becoming a greater issue everyday. In order to optimize it, their biodegradation processes have to be better understood. So far, microcalorimetry has been used worldwide to investigate chemical reactions. For few years now it has also been developed to model and control biological processes. In the case of micropollutants, respirometry is, most of the time, not precise enough to determine biodegradation. That is why, microcalorimetric experiments have been set up. For this purpose, a 2 L Bio-RC1 (Mettler-Toledo) has been modified to reach a resolution of 5-10 mW.L(-1).In this study, the biodegradation rate of standard substrates (Ethanol and Ammonia) by an activated sludge from a full-scale CAS and one from a MBR pilot plant operating in parallel have been compared by means of microcalorimetry. Then few trials to determine the biodegradation of selected pharmaceutical substances, as well as the eventual inhibition induced by them have been made. The first results did not exhibit any biological activity. However, they have displayed inhibition for both studied substances.

Ultrafiltration Membranes System: A Proposal to Remove Emerging Pollutants in Urban Wastewater

“…In the absence of biomass settling problems, MBRs can operate with higher cell residence times, which leads to higher removal efficiencies of biodegradable and hardly biodegradable organic matter. As pointed out by Bouju et al [23,24], when comparing the degradation of micropollutants in MBR and conventional processes under similar conditions, MBR treatment did not improve the removal of those compounds that conventional treatment already removed at a high rate, nor did it improve the removal of recalcitrant compounds that were poorly removed by conventional treatment. However, there seems to be a slight improvement in the removal of those compounds of medium removal by MBR.…”

Membrane Photobioreactor Applied for Municipal Wastewater Treatment at a High Solids Retention Time: Effects of Microalgae Decay on Treatment Performance and Biomass Properties

“…Chlorophyll-a/MLSS(mg/g) = (16.29(A 665.2 − A 750 ) − 8.54(A 652 − A 750 ))/MLSS (1) where A 750 , A 665.2 , and A 652 represent the absorbance at 750, 665.2, and 652 nm, respectively, and MLSS is the mixed liquor suspended solids of the microalgae.…”

“…Wastewater reclamation and reuse have received more and more attention in the world as a result of the increasingly serious freshwater scarcity. At present, various wastewater treatment technologies, such as the activated sludge process (CAS) and membrane bioreactor (MBR), have matured and are widely used in practical applications [1][2][3][4][5][6]. However, most of these systems target organics removal using bacteria, and the treated effluent Membranes 2022, 12, 564 2 of 13 generally contains high levels of nitrogen and phosphorus.…”

Recent developments in forward osmosis membrane bioreactors: a comprehensive review

“…MBR process has been widely preferred for both municipal and various industrial wastewater treatments such as textile wastewaters [81][82][83][84]; oily wastewaters [85][86][87][88]; landfill leachates [89][90][91][92]; tannery wastewaters [93][94][95][96]; pulp and paper industry wastewaters [97][98][99][100]; food processing wastewater [101][102][103][104]; pharmaceutical wastewaters [105][106][107][108], due to its obvious advantages over CASP. As it is widely known, among these wastewaters, oily and petrochemical wastewaters are represented with toxic and refractory characteristics; pharmaceutical industry generates wastewaters containing organic chemicals which are structurally complex and resistant to biological degradation; landfill leachate contains high organic and ammonium nitrogen; tannery wastewaters contain high salt concentrations and inhibitory compounds such as Cr 6+ and sulfur; textile wastewaters include dye and polymer products; pulp and paper industry wastewaters include acids, alcohols and have high temperature; food industry wastewaters exhibit variable COD, pH and temperature values [66].…”