Double Digit Operational Improvements

A Case Study In Optimal Treatment Methodology, Efficiency Gains And Cost Reduction

The Customer

GTI helps customer drive operational improvements by switching to Sulphated PAC treatment

60 MLD raw water treatment plant in Southeast Asia that historically used liquid Aluminum until water quality changed due to high algae presence.

The Challenge

Alum dosage was increased causing high residual AI in treated water. Alum also depressed the alkalinity of the water, requiring a higher dose of hydrated lime. The plant switched to Aluminum Chlorohydrate (ACH) liquid to control residual AI.

  • Switch to ACH drove up treatment costs (as compared to Alum)
  • ACH created tiny floc and settling issue
  • Lower plant filtered water output
  • Higher sand filter backwashing and higher water loss

Collaborative Innovation

GTI partnered with customer to examine problems with both Alum and ACH. Decision made to switch treatment to GPAC3340 (Sulphated PAC) 12% Al203 high basicity PAC, improving overall plant performance and treatment costs.

  • 15-20% savings for customer in coagulant costs

  • Plant returned to full capacity at 60MLD

  • Longer sand filter runs

  • Reduced water loss

  • Improved residual AI compliance

  • Reduction in pH depression

  • The Solution

    Reduction in floc settling enabled plant to return to full capacity at 60MLD, while lowering treatment costs (as compared to ACH)


    The characteristics of raw water can change over time, and the same treatment method that worked in the past might not be optimal today. By fully understanding each treatment option and the overall treatment environment, GTI helped this customer select the best product for the job, thereby driving significant operational improvements. We were able to save the customer 15-20% in coagulant costs. The plant quickly returned to full capacity, with longer sand filter runs and reduced water loss due to back washing. Improved residual AI compliance was also achieved, as well as a reduction in pH depression.