Inventory and Tertiary Treatment of Effluent from Textile Industries in Bangladesh The use of a new system combining an enhanced coagulation, flocculation and filtration M.A.H. Badsha Supervisor: Prof. J.B. van Lier Mentor(s): C.M. Hooijmans H.A. Garcia Hernandez Delft, April 14, 2015

Introduction High TDS Chemical dyes Effluent from textile industries is a great concern in Bangladesh, because High TDS Chemical dyes Major impacts: Causing health consequences Damaging agricultural lands Killing aquatic lives Source: http://oecotextiles.wordpress.com/2009/09/01/dyes-synthetic-and-natural/

Problem Statement Efficient technology to remove color is expensive Limited space for up-gradation Unplanned expansion of textile industry in rural areas As a result, integration of a compact, low cost and efficient technology to remove colour from textile effluent is desired.

Existing ETP of Masco Industries Ltd Inlet Collection Tank Aeration Tank Secondary Clarifier EC Skid DAF unit

Compact Treatment System Figure: Schematic of the polishing unit using AFM grains (Dryden Aqua, 2014) APF- All Poly Floc (mixer of poly aluminum chloride and poly electrolytes) ZPM- Zeta Potential Mixer (static mixer)

Research Questions What technologies are available and in operation to treat textile waste-waters in Bangladesh? What is the colour removal performance of a treatment system using AFM and APF with effluent from an existing wastewater treatment plant at a textile industry?

Research Objectives The specific objectives of the proposed study are: Make an overview of the available technologies Study the adsorption capacity of colour by AFM Study the effect of different flow rates on the performance of the AFM filter media Compare the performance of APF and a conventional coagulant Study the performance of the local sand against AFM Run a pilot AFM system at Masco Industries Ltd

Research Methodology Inventory Study Observe the removal rate of colour by adsorption, coagulation-flocculation and filtration Sample collection and characterization Results and Discussion Conclusions Batch studies Inventory Study Column studies Pilot study at Masco Ind. Ltd

Inventory Study Poor treatment facility (a) No overflow in the primary clarifier (b) Paddy field surrounded by ETP (c) No overflow in secondary clarifier (d) No flow meter

Inventory Study Sludge Management (a) Filter press out of operation (b) Limited space for SDB (c) Dry sludge on SDB (d) Sludge ready to dispose

Optimum Coagulant Dosage Batch Studies Wastewater Sample AFM grade-1 Adsorption Test Optimum Coagulant Dosage

Batch Adsorption Test Result

Optimum Dosing of Coagulant “APF”

Column Studies Schematic of the Column Set-up

Column Set-up at the Lab

Initial Flow Rate = 315 ml/min Results of Column Studies (only feed water without coagulation-flocculation) Initial Color = 282 Pt.Co. Initial Flow Rate = 315 ml/min

Effect of Different Flow Rates (fed with supernatant after coagulation-flocculation with APF) Initial Color = 482 Pt.Co., Supernatant = 184 Pt.Co. F1 = 120ml/min, F2 = 220ml/min and F3 = 350ml/min

Performance of the Column (fed with supernatant after coagulation-flocculation with APF and Aluminium) Initial Color = 572 Pt.Co., Supernatant (using Aluminium)= 382 Pt.Co., Supernatant (using APF) = 207 Pt.Co. and Flow Rate = 315ml/min

Performance of Sand and AFM (fed with supernatant after coagulation-flocculation with APF) Initial Color = 479 Pt.Co., Supernatant = 119 Pt.Co. and Flow Rate = 315ml/min

Backwash Efficiency with Fresh Water (fed with supernatant after coagulation-flocculation with APF) Initial Color = 257 Pt.Co., Supernatant = 64 Pt.Co. and Flow Rate = 315ml/min

Pilot Study at Masco Ind. Ltd Filter Tank APF Dosing Pump Storage Tank Backwash pump

Result of the Pilot Study (In-situ coagulation-flocculation and filtration) Discharge Standard Initial Color = 549 Pt.Co. and Flow Rate = 1m3/h

Backwash Efficiency Flow Rate = 12m3/h

Proposed Treatment Scheme AFM System

Conclusions Regarding the overview on the existing treatment technology: Illegal discharge of wastewater poorly managed and often non-operational coloured effluent is being discharged without any tertiary treatment Sludge management is important and needs immediate attention Regarding activated filter media (AFM) and APF dosing: The AFM media has no significant adsorption capacity (with and without APF dosing) APF is a good coagulant compared to aluminium Performance of local sand is better than AFM filter media Coagulation and flocculation followed by a clarifier could be good enough Regarding AFM system Not suitable as a tertiary treatment system to remove color at a textile industry

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