Improving WTP Performance Tools to Help Achieve Optimization

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1 Improving WTP Performance Tools to Help Achieve Optimization Partnership for Safe Water 2015 Water System Optimization Conference; Hershey, PA Michael W. Grimm, P.E. Aquamize, LLC October 29,

2 Today s Outline 1. Introduction to Optimization 2. Examining processes & procedures 3. What can be learned from data? * Historical data * Special studies 4. Physical inspections 5. Invasive tactics Start with the Big Picture Overview 2

3 Introduction What is Optimization? Highest possible level of WTP performance? Can a WTP produce safe drinking water without being optimized? So, why should a WTP be optimized? 3

4 Introduction Is a WTP the only part of a water system that can be optimized? * Human Resources: Operator training, workforce retention * Finance: Comprehensive audits * Infrastructure: Asset management plans * Distribution operations: Water loss audits, flushing programs, water quality monitoring, operational procedures, O&M manual, etc. 4

5 WTP Optimization Review current operational procedures Assess operator input Review historical water quality and process data Collect new data regarding current status Visually inspect processes and conditions Conduct invasive tests and experiments 5

6 Operational Procedures & Input Do operators have a standard set of operating procedures that are followed? Are those SOPs embraced by all operators? Do the SOPs outline which buttons to push or which knobs to turn, or do SOPs lead thinking? Do operators work together from the same page? WTP have mindset in place to pursue optimization? 6

7 Historical Data What data is collected to assess WTP performance? Where is it collected, where is it stored? Is it utilized routinely by the operators to maintain the WTP processes? Can trends be examined and assessed from the historical data? 7

8 Turbidity Trend Profile 100 Raw Max Filtered Max Settled Combined 10 Turbidity (NTU) Jan-13 Feb-13 Mar-13 Apr-13 May-13 Jun-13 Jul-13 Aug-13 Sep-13 Oct-13 Nov-13 Dec-13 Jan-14

9 Turbidity Trend Profile 10 Raw Max Filtered Combined 1 Turbidity (NTU) May-13 Jun-13 Jul-13 Aug-13 Sep-13 Oct-13 Nov-13 Dec-13 Jan-14 Feb-14 Mar-14 Apr-14 May-14

10 Turbidity Trend Profile 100 Raw Max Filtered Combined 10 Turbidity (NTU) Jan-14 Feb-14 Mar-14 Apr-14 May-14 Jun-14 Jul-14 Aug-14 Sep-14 Oct-14 Nov-14 Dec-14 Jan-15

11 Turbidity Profile: IFE w/ Raw 24-Hour Time Period Filter 1 Filter 2 Filter 3 Filter 4 Raw

12 IFE Turbidity Data 72 Hours Filter 1 Filter 2 Filter June 18 June 19 June 20

13 Special Studies Data Settled water evaluation Backwash water & process evaluation Filtered water turbidity evaluation Jar testing evaluation for chemical dose verification 13

14 Settled Water Turbidity Evaluation Does the settled water meet turbidity goals for < 2 NTU for raw water at or above 10 NTU and < 1 NTU for raw water < 10 NTU? Is there short circuiting within the basin? Is there an observable drop zone in the basin or area within a basin? Set special study to monitor turbidity in basin. 14

16 Establish monitoring locations in basins to determine if turbidity is higher in specific areas of the basin & launders

17 Collect samples at set time intervals Transfer to labeled bottles for analysis

Turbidity Data by Monitoring Location 1.2 1 0.8 0.

18 Turbidity Data by Monitoring Location Filter 2 Filter

19 Clarifier Comparison Turbidity Profile: 1st Run 3 Turbidity (NTUs) Side 1 Side A B C A B C A B Raw Floculator Trough Sed Basin Filter Treatment Stages

20 Backwash Evaluation Measure the media (filter bed) expansion during a backwash Measure the backwash rate and compare to metered values Observe backwash process noting the timing and duration of each stage Observe effectiveness of the backwash Collect water samples to measure turbidity being released by the backwash water 20

21 Use secchi disk or pipe flute tool to measure fluidized level of the anthracite media from reference point

22 Filter Observations During BW Area of more violent air scour upflow through the filter media.

24 Backwash Rate Evaluation Backwash (BW) pumps are usually metered Record BW pump meter reading and duration of BW event to calculate a flow rate (volume divided by time) Use SCADA system data if that is available Keep historical records to tract changes What if there is no pump, there is no meter, and there is no way measure water into filter? 24

25 Backwash Rate Evaluation Be clever!! Assume water coming into the filter as backwash supply is the same as entering the washwater holding basin Measure the rise of expansion in the holding basin over the backwash event From the known surface area of the holding basin, calculate the volume of water for every inch increase in the basin Calculate the flow in terms of volume / time 25

26 Backwash Rate Evaluation - Example In the decant (holding) basin, a 1-inch depth = 202 gallons During the backwash event, the decant basin rose 17 inches during the 12 minute backwash event The total backwash volume used = (202 gallons / inch) x (17 inches) = 3434 gallons The filter basin surface area = 36 ft 2 The backwash rate = (3434 gallons)/(12 min x 36 ft 2 ) = 8 gpm/ft 2. The WTP thought the rate was 15 gpm/ft 2 ooops 26

Backwash Water Comparison Turbidity vs. Time (minutes) 35.0 30.

27 Backwash Water Comparison Turbidity vs. Time (minutes) Filter 1 Filter

28 Filtered Water Turbidity After BW Select sample location to get timely representative samples Use bench model turbidimeter that is properly calibrated If possible, compare to on-line turbidimeter to determine compatibility Collect up to 25 samples to create a good profile curve 28

29 Filter 1 Turbidity Comparison Turbidity vs. Time (minutes) Grab On-line

30 Filter 2 Turbidity Comparison Turbidity vs. Time (minutes) Grab On-line

31 Turbidity Profile after Backwash Turbidity (NTU) Time (Minutes)

32 Media Surface Examination Look for mounding or depressions in the media Look for media pulling away from interior sides of the filter basin Look for mudballs or a blinding floc blanket on the media surface Examine the surface wash arms & nozzles and assess their operability 32

33 Filter Media Surface Inspection

40 Surface depression area Surface mounding area Filter core location Box excavation location Clarifier Wall Filter 1 - Back Filter Feet Probe depth (in) Feet Front Filter Wall

41 Invasive Media Examination Invasive meaning getting into the filter basin Lower platform to stand on filter w/out standing directly on the media Examine surface of media & equipment Probe media with coring bar (steel rebar) Core media in specific locations Excavate media inside a small box 41

43 Using a box excavation, the media can be thoroughly examined

49 Core Sample Turbidity Analysis Collect media from core samples preserving the relative depth of the sample label bag Each core sample should yield 4-5 media samples (1 per bag) Follow standard protocol for rinsing each media sample with tap water and pouring off liquid Repeat rinsing process to collect 500 mls of water Stir collected water and analyze sample turbidity Turbidity values at each core depth = floc retention profile 49

50 0.0 Filter 2 Floc Retention Profile -5.0 Depth Below Media Surface (Inches) Core 15/5 Dirty Core 4/1 Dirty Core 4/1 After Backwash Turbidity (NTU)

51 FILTER 1 Floc Retention Profile - April Depth Below Media Surface (Inches) Filter 1 - Core 4-5 (Dirty) - April Filter 1 - Core 4-5 (Clean) - April

52 Depth Below Media Surface (Inches) FILTER 2 Floc Retention Profile - April 2014 Pre- BW Post-BW

53 0.0 Filter 2 Floc Retention Profile -5.0 Depth Below Media Surface (Inches) Core 15/5 Dirty Core 4/1 Dirty Core 4/1 After Backwash Turbidity (NTU)

54 How Can You Get Started? Develop the culture to pursue optimization Establish goals and a plan to achieve the goals Garner input from all staff and develop SOPs to achieve goals Establish benchmarking tools to monitor progress Use resources available Hire consulting assistance 54

55 Thank you for attending the presentation! Questions or comments? Michael W. Grimm, P.E. Phone:

How Far Can You Push Your Filters? Optimization Lessons

How Far Can You Push Your Filters? Optimization Lessons Marvin Gnagy, P.E. President PMG Consulting, Inc. 51 st OTCO Water Workshop March 6, 2013 Agenda Two recent filter optimization projects Initial