Wastewater Pretreatment at

Church & Dwight Vancouver

Northwest Pretreatment Workshop

September 10, 2013

1,200 gpd High BOD Low SS Trace Zn O&G Vault LOD

4,000 gpd Elevated BOD / SS Acidic pH Elevated Zn BMPs (solids and Zn)

8,800 gpd pH Control MIU Permit

21,000 gpd New PT Design

40,000 gpd PT System Upgrades SIU Permit

2006

2007

2010

2011 2013

Very fast growth, nearly 30% each year…

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

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.

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 5.5 – 10 – 21,000 GPD flow average; 30,000 gpd flow peak

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

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

Turbidity Sensor

Concentrated Waste

Slurry Tank

Plastic Diaphragm Pumps

Basket Strainer

Existing Sludge Tank

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

Multipronged Approach

• Optimized Chemistry

• Staffing Changes

• Modified Plant Design

• Implemented AF-3 Automation

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%

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

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

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

The AF-3 Interface

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.

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.

The AF3 Waste Treatment Control System:

Man vs. Machine

Manual Adjustments Outfall is indicator of system compliance

Underfeed of Chemical

Overfeed of Chemical

COMPLIANCE

Operator should maintain outfall in the desired range

Outfall is indicator of system compliance

The AF3 maintains the outfall within the desired parameters automatically.

No overfeed or underfeed. Maximizes chemical usage while maintaining compliance

Cleaning Mechanism

The AF3 Waste Treatment Control System:

Man vs. Machine

AF3 Automatic Adjustments

Outfall set between 100 and 200 TSS

Sodium Hydroxide Usage

41214 41244 41275 41306 41334 41365 41395 41426 41456

Ratio of NaOH Usage to Volume of Wastewater Discharged

Coagulant Usage

41183 41214 41244 41275 41306 41334 41365 41395 41426 41456

Ratio of Coagulant Usage to Volume of Wastewater Discharged

Sludge Production

41214 41244 41275 41306 41334 41365 41395 41426 41456

Ratio of Sludge Hauls to Wastewater Gallons Discharged

Q & A