Techno-Economic Evaluation of Conventional Activated Sludge and Membrane Bioreactor Systems for Textile Wastewater Treatment in Bangladesh

The textile industry in Bangladesh generated 80% of export revenue in 2023 and provided employment to more than 4 million workers. The textile processing sector together with rapid urban growth has caused an increase in groundwater extraction throughout industrial areas including Dhaka and Narayanganj. The environmental regulations now demand textile manufacturing facilities to install effluent treatment systems. The research evaluates Conventional Activated Sludge (CAS) and Membrane Bioreactor (MBR) wastewater treatment systems at five operational effluent treatment plants (ETP) in Bangladesh. Researcher obtained multi-year records of influent and effluent data together with plant-level energy consumption, chemical usage and sludge wasting data. Laboratory tests, site observations, and operator interviews supported the data collection process to ensure both consistency and data integrity. The evaluation of treatment performance relied on standard water quality indicators together with process parameters. Life Cycle Assessment (LCA) was applied to compare energy, sludge, and chemical footprints for each system. Two decision-making tools, the Treatment Efficiency Performance Index (TEPI) and the Techno-Economic Resilience Score (TERS) were developed to evaluate technical, economic, and environmental aspects under real operating conditions. The research delivers a systematic dataset together with an analytical framework to assess textile sector effluent treatment performance in Bangladesh. The research data demonstrated that MBR systems achieved better Biochemical Oxygen Demand (BOD) and Total Suspended Solids (TSS) removal performance in most scenarios, as expected. However, the TSS and BOD effluent levels in one MBR system (Factory 2) showed relatively large fluctuations. Statistical analysis showed significant variations in BOD and TSS but not in COD. Yet overall, MBR systems demonstrated better removal efficiency as predicted. Sludge waste (Kg/m³ of bioreactor) was lower for both MBR plants compared to CAS; however, CAS plants successfully met the local and international apparel buyer’s effluent discharge limits for BOD, COD, and TSS. While most studies reveal that MBR systems provide superior removal capabilities overall, both MBR and CAS systems require consistent operational practices. Ultimately, the long-term success of a treatment system is determined more by operational control than by the choice of technology alone.

Name thesis:degree_name

Master of Science (MSc)

Discipline thesis:degree_discipline

Engineering – Civil

Grantor dc:publisher.institution

Graduate Studies

Year dc:date.issued

2025

Author dc:creator

• Rajeeb, M Aslamur Rahman

Advisor dc:contributor.advisor

• Chu, Angus

Committee members dc:contributor.committeemember

• Achari, Gopal
• Huang, Wendy

Statement dc:rights

• University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.

Language dc:language.iso

en

DOI

https://dx.doi.org/10.11575/PRISM/50356

OAI identifier oai:identifier

oai:ucalgary.scholaris.ca:1880/122763