Wastewater Pretreatment at Church & Dwight Vancouver. Northwest Pretreatment Workshop September 10, 2013

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1 Wastewater Pretreatment at Church & Dwight Vancouver Northwest Pretreatment Workshop September 10, 2013

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3 ,200 gpd High BOD Low SS Trace Zn O&G Vault LOD ,800 gpd ph Control MIU Permit 4,000 gpd Elevated BOD / SS Acidic ph Elevated Zn BMPs (solids and Zn) 21,000 gpd New PT Design ,000 gpd PT System Upgrades SIU Permit Very fast growth, nearly 30% each year

4 What does CHURCH & DWIGHT make? Globally - Consumer Packaged Goods Household products: Arm & Hammer products Personal Care products: Nair, Trojan, OxiClean Specialty products Vancouver & Ridgefield Washington Gummy vitamins for children & adults

5 Facility Overview Vancouver, WA 7 Buildings total 2 Manufacturing plants 1 Packaging line 3 Warehouses QC Laboratory R&D Center 450 employees Process wastewater feeds to the treatment system from two manufacturing plants and a washroom.

6 Wastewater Characterization Major Constituents Water Gelatin Pectin Sugar Corn starch Zinc gluconate, zinc citrate Caustic soda Citric Acid, Lactic Acid, Malic Acid, Fumaric Acid Natural colors and flavors Permit Requirements Zinc removal to 1.64 mg/l (24 hour composite limit) ph neutralization to a discharge range of ,000 GPD flow average; 30,000 gpd flow peak

7 Treatment Challenges of Early 2012 Lack of instantaneous/continuous way to measure zinc concentration Removal of zinc trapped in gelatin solids Original design lacked final ph adjustment Controlling microbial growth in the settling tank effects on ph Accurate chemical dosing for large swings in solids content and ph (over/under dosing) Training and experience level of operators & lack of dedicated operator Equipment malfunction / break down Lack of straining for debris February 2011

8 Modified Plant Design Equalization Tank to Damper Large Swings EQ went from 500-gallons to 8,000-gallons System Flow Modifications Previous Design Allowed for Flow Surges in Excess of 120-GPM. New Design Caps Max Flow at 60-GPM w/ Average Flow of 25-GPM. Maintains Proper Clarifier Rise Rate. Robust Changes in Automation/Control/Alarming AF-3

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10 Basket Strainer Concentrated Waste Slurry Tank Plastic Diaphragm Pumps Existing Sludge Tank Turbidity Sensor

11 Chemical/Automation Challenges Extraordinarily Dynamic Waste Stream ph from 2-10 TSS from 50-10,000 PPM Zinc from 0 30 PPM Large BOD Swings Depending on Equipment CIP Strong Chelating Agents Microbes Long Retention Times High Solids

12 Multipronged Approach Optimized Chemistry Staffing Changes Modified Plant Design Implemented AF-3 Automation

13 Chemistry Changes System was Using Commodity Aluminum Chlorohydrate (ACH) Changed from ACH to ACH/Organic Polymer Blend Result: Coagulant Usage Reduced by >30% Sodium Hydroxide Usage Reduced by >5% Sludge Produce Reduced by >30%

14 Staffing Changes C&D (NNP at the time) hired Environmental Engineer with direct wastewater and permit compliance responsibility Additional operator was added to the team with over 10-years wastewater treatment experience at a complex remediation site 12 hours of dedicated coverage 7 days a week with two operators

15 Automation Hurdles Specific to Church & Dwight Facility Variable Waste Stream (chemical requirements vary from 50-PPM to 10,000-PPM) Automation and control had only accounted for swings in flow (VFD). It did not account for loading changes. Control was based 100% on human interaction Changes in chemical set-points occurred a few times daily based on a single jar test. The system load changed minute-to-minute

16 AF-3 Goals Minimize Maintenance or Human Interaction. Reliable Control of Multiple Chemicals at Once. Provides Either a Feed-Forward or Feedback Configuration, or a Combination of Both Under Certain Circumstances. Control Multiple Parameters to a Single Compliance Metric. Remotely Accessible. Provided Ongoing Data-Logging. Removed Human Error From the Control Equation. Affordable. Application Specific

17 The AF-3 Interface

18 AF-3 Benefits Enables management to set the outfall water parameters based on the necessary water quality. Makes chemical adjustments every 57 seconds based on quantity of water flow and outfall parameter set points. Has the capability to monitor and feed 5 separate chemicals to include acids, bases, coagulants and polymers. Stores and graphs data from all monitored system points to include: outfall quality, flow (gpm), chemical feed (ppm), and ph.

19 AF3 Benefits - Continued Allows remote access to multiple computers through a facility s intranet. Fully automated system that takes operational responsibilities so operators can better utilize time for other important tasks. Provides periodic self-cleaning for probes to limit fouling, the need for calibration, and accurate chemical dosing. Manually determined start-up dosing to prohibit initial overfeed. Operates 24 hours per day, 7 days per week. The only equivalent form of system is a SCADA cost prohibitive.

20 The AF3 Waste Treatment Control System: Man vs. Machine Outfall is indicator of system compliance Manual Adjustments Underfeed of Chemical Overfeed of Chemical Operator should maintain outfall in the desired range COMPLIANCE

21 The AF3 Waste Treatment Control System: Man vs. Machine Outfall is indicator of system compliance AF3 Automatic Adjustments No overfeed or underfeed. Maximizes chemical usage while maintaining compliance Cleaning Mechanism The AF3 maintains the outfall within the desired parameters automatically. Outfall set between 100 and 200 TSS

22 Sodium Hydroxide Usage Ratio of NaOH Usage to Volume of Wastewater Discharged

23 Coagulant Usage Ratio of Coagulant Usage to Volume of Wastewater Discharged

24 Sludge Production Ratio of Sludge Hauls to Wastewater Gallons Discharged

25 Q & A