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STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
ROYAL MELBOURNE GOLF CLUB
OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
NATIONAL STORMWATER CONFERENCE 2018
PETER GORDON
KURT DAHL
SLIDE 1
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
OVERVIEW
► Background
- Initial solution
- Need for more
► Upgraded Treatment Solution
- Water Treatment Plant
- Stormwater Victoria Award: “Excellence in Infrastructure” - 2010
► Knowledge and Experience Journey – 8+ years of Operation
- Process changes
► Conclusions and Recommendations
SLIDE 2
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
BACKGROUND
SLIDE 3
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
ROYAL MELBOURNE GOLF CLUB
► Ranked amongst the best golf courses in the world
► Continued drought during 2007 – 08
- Criticism of using drinking water
- Water restrictions
- Negative impact of tankers (recycled water)
- Playing surfaces deteriorated substantially
- Including impact of saline bore water
► RMGC examined alternative solutions to diversify supply
- Already using groundwater, although limited availability
► Stormwater identified as preferred solution to supplement groundwater
SLIDE 4
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
INITIAL SOLUTION
► 2008 – initial investment in stormwater harvesting scheme
- Initial design intent: harvest 60 ML/year of stormwater
SLIDE 5
Infrastructure Purpose
Stormwater Harvesting Pipe Stormwater is harvested from a Melbourne Water stormwater pipe that runsunder the East course.
Gross Pollutant Trap Stormwater flows under gravity via a diversion chamber into the Gross PollutantTrap (GPT) to catch gross pollutants in the water greater than 3mm.
Pump Wet Well From the GPT the water flows into pump wet well, from which a set of transferpumps initially pumped the water to the new storage lagoon (see later change tothis configuration).
Accumulator Excess water from the GPT is directed to an underground 1ML accumulator thatis connected directly to the pump wet well.
Storage Lagoon The 35ML storage lagoon is designed for storage of stormwater and groundwaterand assists in buffering water supply and irrigation demand over the course of ayear.
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
NEED FOR MORE
► 20 ML stormwater harvested vs. 60 ML design
► Permeate Partners engaged in August 2008
- Revised project objectives
► Increased water supply
- Optimisation of stormwater/groundwater supplies
- Maximising recovery of any additional treatment
► Stormwater treatment
- Conform to National Guidelines
- Unrestricted irrigation
- Reduce / remove solids, nutrients, oil & grease
- Reduce risk of algal blooms
► Groundwater treatment
- Reduce salt levels
- Sufficient for use on all surfaces (greens + fairways)
► Maximise reuse of existing infrastructure
SLIDE 6
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
UPGRADED TREATMENT SOLUTION
SLIDE 7
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
RMGC UPGRADED FLOWSHEET
SLIDE 8
Stormwater
extraction
Stormwater Drain
Underground
accumulator
Bioretention FilterStorage
Lagoon
Ultra
FiltrationChlorination
Irrigation
storage
Reverse
Osmosis
Surface
Wetland
RO Permeate
UF
Waste
Tablet
Chlorinator
Groundwater
system
(extends across
the course)
Modified to allow low flow capture
Manage: TSS, O&G, Nutrients
New Infrastructure
Modified Infrastructure
Existing Infrastructure
Optimised to increase yield
Disinfection and pre-treatment
Practice
fairway
irrigation
RO Brine
Salt load management
Maximise water recovery
Maximise water recovery
Disinfection + residual
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
WATER TREATMENT PLANT
► Feed is a combination of stormwater and groundwater
- Varies at different times of the year
► UF capacity = 1.6 MLD
► RO capacity = 0.4 MLD
- Side stream treatment
► Overall plant achieves ~ 98% recovery across the year
- UF backwash recovery
- Brine irrigation
SLIDE 9
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
PROCESS PERFORMANCE
► Membranes commissioned in January 2010
► Stormwater Victoria Award for Excellence in Infrastructure in 2010
- Stopping here would not be the complete story
- The journey continues
► First 10 months, stable operation
- Dec/Jan increased level of fouling
- Combination of reversible and irreversible fouling
- Repeatable trend
- pH fluctuations
- Membrane integrity not compromised
SLIDE 10
PE
RM
EA
BIL
ITY
TIME
Summer Periods
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
KNOWLEDGE & EXPERIENCE JOURNEY
SLIDE 11
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
► Feed source – 38 ML dam: Key observations in summer
- Noticeable algae formation
- Increase in feed water pH
- Increase in feed water turbidity
- Regular strainer blockage (slime, NOM and living organisms)
- RO biological fouling (confirmed with membrane replacement)
EARLY CONCLUSIONS (BUT NOT THE END )
SLIDE 12
► Everything pointed towards UF membrane organic based fouling
► Changes implemented:
- Coagulant dose (ACH based)
- Shock biocide dosing
- Cleaning trials with speciality cleaners
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
► Year 8, time to replace the membranes
- Overall deterioration in permeability, potentially impacting capacity
► Membrane selection process
► Need more Knowledge (field experience)
- Otherwise more of the same
► Independent Membrane autopsy and cleaning study
- Membrane360
- Initial focus was to identify best cleaning method to maintain permeability
- Identify foulant to identify best cleaning approach
BUT…….THERE WAS A SURPRISE
WHAT DO WE DO NOW….SLIDE 13
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
► No obvious fouling, discolouration or solid build-up
AUTOPSY OUTCOME
SLIDE 14
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
► SEM Images identified extensive scaling (membrane surface)
AUTOPSY OUTCOME
SLIDE 15
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
MORE IMAGESSLIDE 16
Crystalline structure on membrane
surface
Crystalline structure
inside membrane
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
MORE IMAGESSLIDE 17
Crystalline structure on membrane
surfaceX-section
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
MORE IMAGES (CHROMATIC ELEMENTAL IMAGING)SLIDE 18
CEI Image of the x-section of a more fouled fibre
CEI Image of the inside of a fibre (permeate side)
→→
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
MORE IMAGESSLIDE 19
CEI Image of the x-section of a more fouled fibre
CEI Image of feed side of a more fouled fibre
→→
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
PROCESS CHANGES
SLIDE 20
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
► Main cause of fouling
- Calcium Carbonate (primary)
- Aluminium (secondary, although more distributed)
- Very little organic fouling
► Cleaning study indicated fouling is irreversible, however proved the following:
- Low pH cleaning to be below 2.5 (above 2!)
- Maximise high pH clean
- Boost clean with a high pH speciality cleaner recommended
- Provided best performance recovery
- High cost / low frequency
AUTOPSY CONCLUSIONS
SLIDE 21
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
PROCESS CHANGES (SUMMARY)SLIDE 22
Observation Cause Process Changes
Calcium Carbonate
scaling
• High feed pH decreasing
solubility, especially during
summer.
• Insufficient pH reduction
during acid chemical clean to
adequately remove the scale
on the membrane surface.
• Feed water composition.
• Feed pH control introduced (sulphuric acid),
with a PID acid dosing loop to control to a
setpoint to increase calcium carbonate
solubility at the lower pH.
• Optimised low pH membrane cleaning
procedure with the inclusion of a pH control
step to maximise removal of carbonate scale.
• Changed the source water for the chemical
clean to rather use RO permeate (reduce risk
of scale formation during high pH clean).
Aluminium scaling • High feed pH, higher Al
solubility, reducing
effectiveness of coagulation
process.
• Inadequate coagulant dose
control.
• Feed pH control (same as above) to ensure
coagulant process operates within optimum
pH range.
• Optimised high pH membrane cleaning
procedure with the inclusion of a pH control
step to maximise removal of Al scale.
• More regular jar testing to optimise coagulant
dose control along with linking dose control to
feed turbidity.
Irreversible fouling • Hardened scale. • Introduction of planned membrane cleans
using speciality membrane cleaners to target
Al and Carbonate (Boost clean).
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
OTHER PROCESS CHANGES
SLIDE 23
► To maximise benefits additional storage was required
- Additional storage added to the scheme
- Allowed more flexibility in stormwater and groundwater harvesting
- Stormwater needs storage……..
► pH correction
- Treated water pH correction to reduce impact of alkalinity on soil and turf health
- Control of feed pH to optimise coagulation process performance
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
► System has operated successfully
- Project objectives achieved
- Treated water quality objectives exceeded
- All available water used for irrigation
► +350 ML of stormwater treated
► Process optimisation and troubleshooting been fundamental in ensuring ongoing success (not just stopping at the award)
► Performance and sharing of results provides a good basis into the future as a template for future stormwater treatment facilities, providing design, operation and maintenance experience for stormwater harvesting.
► Indirect potable re-use testing????
CONCLUSIONS AND RECOMMENDATION
SLIDE 24
What if….we had done the membrane autopsy
earlier….
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
► Royal Melbourne Golf Club, in particular:
- Alan Evans – driving the project from the beginning
- Richard Forsyth – course Superintendent
- Club support and operations staff (no formal WTP operations training/experience)
“For their continuing support of the project and the value they have placed on following industry best practices and reducing their reliance on potable water”
ACKNOWLEDGEMENTS
SLIDE 25
STORMWATER 2018RMGC – OVER 8 YEARS OF STORMWATER HARVESTING AND TREATMENT EXPERIENCE
COMMERCIAL IN CONFIDENCE
QUESTIONS?
SLIDE 26