A New Charge Based Coagulant Dose Control Instrument

EPA Contract Number: 68D40057
Title: A New Charge Based Coagulant Dose Control Instrument
Investigators: Jorden, Roger M.
Small Business: Clear Corporation Enterprises Inc.
EPA Contact: Manager, SBIR Program
Phase: I
Project Period: September 1, 1994 through March 1, 1995
Project Amount: $55,000
RFA: Small Business Innovation Research (SBIR) - Phase I (1994) RFA Text |  Recipients Lists
Research Category: Water and Watersheds , SBIR - Water and Wastewater , Small Business Innovation Research (SBIR)


Enhanced coagulation will soon be required for drinking water filtration plants nationwide under new EPA regulations. Coagulant chemical dosage determines the effectiveness for removing pathogenic particles and organic acids. For reliable purity, on-line coagulant control instrumentation is necessary. The best available controller, streaming current detection (SCD), is useful as a "homing" device. But its readings, based on charge, drop following coagulation. Consequently, it defies calibration and is a worthless tool in the frequently required process of coagulation enhancement. Colloid charge titration (CCT) is a promising alternative to SCD but it lacks a foolproof endpoint detector. Consequently, reliable drinking water purification is elusive for many plants and the broad population they serve nationwide.

Proposed is a new endpoint detector that would allow coupling of jar testing with on-line control because it promises to give charge readings which are stable with time, and are identical for both coagulation enhancement testing and on-line operation. Questions to be addressed for this feasibility evaluation are:

  1. Is the new CCT detector robust and are the readings stable with time for alum, the common coagulant?
  2. Will the end users, the plant operators, be able to couple jar testing and on-line control through CCT readings, even in small systems?

The proposed program is attractive because it promises to provide the workmen with a "steel" vs a "rubber" tape measure for performing ongoing and singularly most critical task in determining purity for drinking water filtration plants, coagulation enhancement. Consequently, episodes like the March 1993 Milwaukee disease outbreak could more likely be prevented. Continuous, reliable coagulation maximizes removal of the disease causing cyst particles that were responsible in this preventable outbreak.

Supplemental Keywords:

Coagulant Dose Control, Colloid Charge Titration., RFA, Scientific Discipline, Water, Ecosystem Protection/Environmental Exposure & Risk, Chemical Engineering, Environmental Chemistry, Chemistry, Monitoring/Modeling, Environmental Monitoring, Drinking Water, Engineering, Environmental Engineering, monitoring, coagulation, colloid charge titration, exposure and effects, coagulant dose control, exposure, drinking water filtration plants, charged based coagulant, treatment, endpoint detector, drinking water treatment, drinking water contaminants

Progress and Final Reports:

  • Final
  • SBIR Phase II:

    A New Charge Based Coagulant Dose Control Instrument