Technology testing in BETV-SAM Round 1:

Quick Facts:

• Technologies tested:

  Household Scale Technologies: Shapla, Nelima, EIP Star, CIWP
  Community Scale Technologies: Wholly Water, Apyron, Alcan

• Well locations:

  Chapai, Dohar, Kolaroa, Ishwardi, and Nabinagar. Each technology was tested on five wells (35 wells in total) in the five hydrogeologically different regions of Bangladesh with two replicate units in two regions.

• Test Plans:

  As each technology has its own specific operating principles (amount of water that can be passed through it, water treatment ability etc), testing had to be tailored to the technology (i.e. the field tests were technology specific).

   

More details:

The Bangladesh Environmental Technology Verification - Support to Arsenic Mitigation (BETV-SAM) Round 1 program conducted an objective assessment of thirteen arsenic removal technologies (ARTs) that had been submitted for performance verification, and selected seven technologies for field testing and performance verification. Each technology was deployed to five hydrogeologically distinct regions of Bangladesh and was tested on five tube wells (TWs) (with replicate units installed and tested on two TWs). Raw and treated water samples were collected at regular intervals and were analysed for arsenic and other water quality parameters. The data were analyzed using standard statistical software and the performance of individual ARTs have been evaluated and compared with the proponent's claim.

The program in consultation with proponents developed Technology Specific Test Plans (TSTPs) for each technology and tested each technology on five TWs (35 wells in total) in five hydrogeologically different regions of Bangladesh with two replicate units in two regions. TWs with water quality parameters, such as concentrations of arsenic, pH, iron, phosphate (PO₄^3-), silicate and metals, that satisfied proponents criteria and met certain physical conditions were selected for field testing and performance verification.

Each technology was operated and maintained following the proponents Operation and Maintenance (O&M) manual. The coagulation/flocculation technologies were tested for 10 - 20 days and the sorption technologies were operated until: a) arsenic breakthrough ([As] > 50 µg/L), or b) produced enough arsenic-safe water and met the proponent's performance claim. During the testing period, samples were taken at regular intervals and were analyzed for concentrations of arsenic, iron, phosphate, silicate, alkalinity, bacterial contamination and total metal scan following these procedures:

• Total Arsenic Analysis: Five (5) to seven (7) raw groundwater samples and 10 - 20 treated samples were collected from each technology and analyzed for total arsenic (using atomic absorption spectroscopy) in one of the designated analytical laboratories¹, thereby ensuring that both the influent and effluent water were sufficiently characterized.
• As(III), Total Iron, Phosphate and Microbial Analyses: At least three influent and three effluent samples are collected from each technology and analyzed (AAS-HG) in one of the designated analytical laboratories in Bangladesh for concentrations of As(III), Fe (total), PO₄^3-, and faecal and total coliforms².
• Field Analyses: Five (5) samples of influent and effluent were analyzed in the field for alkalinity and chlorine (for ARTs that employed chlorine) analysis. In addition, the pH, conductivity, and turbidity of 5 influent samples and 10 treated effluent samples were measured using portable meters, following standard protocols.
• QA/QC Samples: Duplicate, field blank, and reference standard samples were also collected and sent to the Canadian Reference Lab for QA/QC purposes.

A number of influent and effluent water samples were also collected and analyzed for anions, metal scan (Reference Lab using ICP-MS techniques), volatile organic compounds, and chlorinated phenols (for ARTs employing chlorine).

¹ The designated laboratories were selected amongst laboratories that participated in a round robin sample analysis prior to the field testing and performed well.
² Bacteriological samples were analyzed for faecal coliform; 10% are tested for total coliform.