Reduction of Cost and Environmental Impact in the Treatment of Textile Wastewater Using a Combined MBBR-MBR System

Abstract

A hybrid Moving Bed Biofilm Reactor—Membrane Bioreactor (MBBR-MBR) was developed for the treatment of wastewater from a Spanish textile company. Compared with conventional activated sludge (CAS) treatment, the feasibility of this hybrid system to reduce economic and environmental impact on an industrial scale was conducted. The results showed that, technically, the removal efficiency of COD, TSS and color reached 93%, 99% and 85%, respectively. The newly dyed fabrics performed with the treated wastewater were qualified under the standards of the textile industry. Economically, the values of Capital Expenditure (CAPEX) calculated for the hybrid MBBR-MBR system are profitable because of the reduction in Operational Expenditure (OPEX) when compared with CAS treatment, due to the lower effluent discharge tax thanks to the higher quality of the effluent and the decolorizing agent saved. The result of Net Present Value (NPV) and the Internal Rate of Return (IRR) of 18% suggested that MBBR-MBR is financially applicable for implantation into the industrial scale. The MBBR-MBR treatment also showed lower environmental impacts than the CAS process in the life cycle assessment (LCA) study, especially in the category of climate change, thanks to the avoidance of using extra decolorizing agent, a synthetic product based on a triamine.

Evaluation of a Hybrid Moving Bed Biofilm Membrane Bioreactor and a Direct Contact Membrane Distillation System for Purification of Industrial Wastewater

“…The removal efficiency of MBBMR for TSS varied from around 45% at the beginning of the testing period to negative values at the end which indicated insufficient acclimatization of microorganisms in the tank. While under the normal and steady operation of MBBMR, it is expected to achieve stable TSS T1 values and high TSS removal efficiency [ 26 ], the TSS T1 values increased with the increase in TSS 0 values. This indicates that the testing period of 3 weeks is not adequate to achieve the required biodegradation rate of biomass.…”

Modelling for the Efficient Effluent Dye Removal to Reuse Water and Salt

“…The values fixed for dye concentration and conductivity corresponded to the maximum and minimum values usually found for reactive dye textile wastewater. The range of pH values was defined by considering the following considerations: (i) the usual value of pH in real reactive dye effluents (9)(10)(11), (ii) the optimal working range of electrodes (>5), and (iii) the equilibrium of the oxidant species generated from the chloride ion. The different factors are defined as: pH; C NaCl : conductivity due to the NaCl added (mS/cm); C total : total conductivity of the experiment adjusted with NaCl + Na 2 SO 4 (mS/cm); and d: dye concentration (g/L).…”

“…These tertiary treatments are based on the addition of decolourising agents, and most of them are derived from tertiary and quaternary amines. The production of these amines entails a high impact in the category of climate change, due to the high energy consumption of amine synthesis [10]. It is important to highlight that none of these treatments allow the reuse of water.…”

Chemical Cleaning and Membrane Aging in MBR for Textile Wastewater Treatment

“…Membrane technology has become an attractive alternative for textile wastewater treatment [ 6 , 7 ]. Membrane bioreactor (MBR) possesses the merits of small footprints, low maintenance, low sludge production, and high removal of organic and recalcitrant pollutants [ 1 , 8 , 9 ]. Nanofiltration (NF) or reverse osmose (RO) could intercept non-biodegradable chemicals or dyes and, thus, enable recycling in textile wastewater treatment [ 2 , 10 ].…”