Streaming Current Detectors

What Is It? On-line monitor that measures net charge density of a water sample Allows continuous monitoring & control of coagulation process in water & wastewater treatment Provides effective polymer control in sludge dewatering processes

Models SC2200- base unit (usually used with RM6200 or RC7200 or strip chart recorder) SC4200- base unit with LCD display, gain and zero capabilities (allows set point to be chosen) SC5200- base unit with PID controller (allows for automatic control of coagulant dose pumps

Chemicals Used with SCD (Coagulants) Inorganic Salts Alum Aluminum Chloride Poly Aluminum Chloride (PAC) Ferric Sulfate Ferric Chloride Organic Polyelectrolytes (Polymers)

Working Description Net charge density analyzer - measures the amount of free charges left after coagulation dosing and mixing Reciprocating plunger moves sample past electrodes that measures charge in the form of an induced current in the electrode Main circuit board amplifies, processes and displays

SCD Applications Influent Clarification Wastewater Treatment Industrial and Municipal Plants Wastewater Treatment Sludge Dewatering Belt Filter Presses Centrifuge

Selling the Benefits of the SCD Optimization of Coagulant Feed ($$$) Possible Reduction in Chemical costs More effective use of Manpower Decrease frequency of jar testing Consistent Water Quality Compliance with environmental regulations Increase in filter run time Reduced downtime due to equipment fouling

SCD & Influent Clarification River Coagulant Feed Clarifier Effluent SCD Mix Tank Settling Basin Pump Coagulant Feed Mix Tank Sludge Draw Off

SCD & Influent Clarification Chemical is fed to “charge” dirt and particles in the water Floc settles out in either a clarifier or settling basin Customer uses jar testing to determine the right concentration of chemical needed for best performance SCD allows customer to establish a “setpoint” based on the right concentration

SCD & Wastewater Treatment Typical Wastewater Clarification System Waste Sludge Wastewater Inlet Effluent Primary Clarifier Aeration Basin Secondary Clarifier Mix Tank Return Sludge SCD Sample Polymer Feed

SCD and Wastewater Treatment Same principle applies as to influent clarification. Treatment of Waste stream Due to higher solids contact, use cyclone separator and/or jet wash Some wastewater clarifiers do not use coagulant

SCD and Waste Treatment (Dewatering- Belt Filter Press) Typical Belt Filter Press System Polymer Feed Belt Filter Press Thickener Waste Sludge Mixer From Secondary Clarifier or Process SCD Sludge Cake Sample (Filtrate)

SCD and Waste Treatment (Dewatering- Belt Filter Press) Thickener increases solids percent from 1% to 2-3% Polymer is added to sludge for coagulation Sludge is pressed between two tensioned belts and passed over and under rollers Water, part sludge and residual polymer are tested by sampling filtrate SCD “setpoint” is based on optimum filtrate charge. Because of solids content, use cyclone separator and/or jetwash

Typical Continuous Bowl Centrifuge

SCD and Waste Treatment (Dewatering- Centrifuge) Two principal elements of a centrifuge are the rotating bowl and the inner screw conveyor Solids settle due to centrifugal force from bowl rotation Screw conveyor picks up solids and conveys them to discharge port Water, part sludge, residual polymer are tested by sampling centrate Because of solids content, use cyclone separator and/or jetwash

SCD and Water Purification (Reverse Osmosis) Influent Water Primary Filter Intermediate Processes SCD Cartridge Filter Coagulant Feed Reverse Osmosis Units Permeate

SCD and Water Purification (Reverse Osmosis) Pre-treatment of influent water for RO system Control coagulant injection feed to minimize over- coagulation that causes fouling of RO membrane Set point is defined to give slightly negative reading ensuring minor under coagulation condition

Competition CHEMTRAC (MODEL 2000XP) HF SCIENTIFIC (MICRO 200 SCM) NORCROSS, GEORGIA HF SCIENTIFIC (MICRO 200 SCM) FORT MYERS, FLORIDA LECHINTECH (SCD 3000) STANGER, SOUTH AFRICA

What Can we Offer? Demo units available for 30 day trial Delivery of new units in 2 weeks or less Trade in for older SCD units

SCD and Waste Treatment (Dewatering- Centrifuge) Typical Centrifuge Dewatering System Influent Slurry Feed Slurry Discharge Polymer Feed SCD