Engineer Research and Development CenterUS Army Corpsof Engineers
WATER CONSERVING TECHNOLOGY OPTIONS FOR
INSTALLATION USE
Richard Scholze and Annette Stumpf
U.S. Army Corps of Engineers
ERDC-CERL
Champaign, IL
Richard Scholze and Annette Stumpf
U.S. Army Corps of Engineers
ERDC-CERL
Champaign, IL
Engineer Research and Development CenterUS Army Corpsof Engineers
Water Conservation
Why Do It?
Delay or Avoid Expensive Water Supply and Wastewater Treatment Capital Projects
Helps Protect Fundamental Natural Resources Through Ecosystem Protection, Protect Current Quality of Life and Provide for Future Generations
Minimize Effects of Drought
Why Do It?
Delay or Avoid Expensive Water Supply and Wastewater Treatment Capital Projects
Helps Protect Fundamental Natural Resources Through Ecosystem Protection, Protect Current Quality of Life and Provide for Future Generations
Minimize Effects of Drought
Engineer Research and Development CenterUS Army Corpsof Engineers
Federal Sector
Executive Order 13123
Requirements
Water Management Plan
Implementation of FEMP BMPs
Executive Order 13123
Requirements
Water Management Plan
Implementation of FEMP BMPs
Engineer Research and Development CenterUS Army Corpsof Engineers
Selected Conservation Opportunities
• Domestic Use
• Administrative/Commercial/Institutional
• Domestic Use
• Administrative/Commercial/Institutional
Engineer Research and Development CenterUS Army Corpsof Engineers
Toilets
Current Lowflow Designs Much Better
Dual Flush Toilets
Waterless Urinals
Current Lowflow Designs Much Better
Dual Flush Toilets
Waterless Urinals
Engineer Research and Development CenterUS Army Corpsof Engineers
Dual Flush Toilet
Engineer Research and Development CenterUS Army Corpsof Engineers
Dual Flush Toilet Fixtures
Only Recently Actively Marketed in U.S.4 New Manufacturers in 2004, Others Watching MarketplaceCosts Becoming CompetitiveDo They Save water?3 Study Summary
20-30% Savings in WaterWeighted Average Flush 1.1 to 1.3 gpf vs 1.6Customer Satisfaction Positive, Liked OptionAdvantage – Seldom ClogsDisadvantage – Smaller Water Spot, Possible StreakingPayback - 8.5 Years for $300 Toilet, 10 Flushes/day,
Combined W/WW Cost of $3.79/1000 gallons
Only Recently Actively Marketed in U.S.4 New Manufacturers in 2004, Others Watching MarketplaceCosts Becoming CompetitiveDo They Save water?3 Study Summary
20-30% Savings in WaterWeighted Average Flush 1.1 to 1.3 gpf vs 1.6Customer Satisfaction Positive, Liked OptionAdvantage – Seldom ClogsDisadvantage – Smaller Water Spot, Possible StreakingPayback - 8.5 Years for $300 Toilet, 10 Flushes/day,
Combined W/WW Cost of $3.79/1000 gallons
Engineer Research and Development CenterUS Army Corpsof Engineers
Waterless Urinals
Engineer Research and Development CenterUS Army Corpsof Engineers
Waterless Urinals
Becoming Widespread (Thousands in Use)
Several Manufacturers
Focus on Non-Residential Installations
Concern Over Proper Maintenance
Ex. Presidio of Monterey
173 Urinals Replaced – Classrooms, Administrative and Recreational Facilities in 48 Buildings
Expected Savings - 11,500 gal/day or 3 million gallons per year
Becoming Widespread (Thousands in Use)
Several Manufacturers
Focus on Non-Residential Installations
Concern Over Proper Maintenance
Ex. Presidio of Monterey
173 Urinals Replaced – Classrooms, Administrative and Recreational Facilities in 48 Buildings
Expected Savings - 11,500 gal/day or 3 million gallons per year
Engineer Research and Development CenterUS Army Corpsof Engineers
Food Service
• Pre-Rinse Spray Valves
• SOMAT System
• Boilerless Food Steamers
• Air-cooled Icemakers
• Water Conserving Dishwashers
• Pre-Rinse Spray Valves
• SOMAT System
• Boilerless Food Steamers
• Air-cooled Icemakers
• Water Conserving Dishwashers
Engineer Research and Development CenterUS Army Corpsof Engineers
Pre-Rinse Spray ValvesTypical Restaurant/Food Service – Up to 50% of Dishwashing
Water Consumed by Pre-rinse Spray Valve to Remove Food From Dishware, Utensils and Pans
Newer Units 1.6 gpmOver 3.0 for Non-efficient ValvesUsually Use Heated WaterTraditional “Showerhead” Type Spray PatternOrifices Become Restricted with TimeNew “Knife-like” Continuous Spray – More Efficient, Less
Mineral Buildup
Ex. Water savings 77,050 gal/yearGas Savings 335 therms/year; 7600 kWh
Typical Restaurant/Food Service – Up to 50% of Dishwashing Water Consumed by Pre-rinse Spray Valve to Remove Food From Dishware, Utensils and Pans
Newer Units 1.6 gpmOver 3.0 for Non-efficient ValvesUsually Use Heated WaterTraditional “Showerhead” Type Spray PatternOrifices Become Restricted with TimeNew “Knife-like” Continuous Spray – More Efficient, Less
Mineral Buildup
Ex. Water savings 77,050 gal/yearGas Savings 335 therms/year; 7600 kWh
Engineer Research and Development CenterUS Army Corpsof Engineers
SOMAT Disposal System
What is It? Food Waste Pulping and Dewatering System to Replace Scraping Trough and Garbage Disposal System in Kitchens
Uses Water to Move Material Scraped Off Plates to a Pulper Which Cuts Solid Waste into a Slurry
Slurry Flows From Pulper to Water Extractor Unit Which Removes Water to Produce Odor-Free, Semi-dry pulp
Extracted Water Returned to Feed Tray to Complete Closed-loop CycleWater Level Automatically ControlledSmall Amount 1-3 gpm Bled Off and ReplacedSystem Eliminates Need to Separate Food Scraps, Paper and Plastic WasteReduces Staff Time by HalfEx. POM 2 Systems, 2 Bldgs. – Cuts Daily Water Consumption from 9,240 to
1680 gallonsSavings 2.76 Million gal/year
What is It? Food Waste Pulping and Dewatering System to Replace Scraping Trough and Garbage Disposal System in Kitchens
Uses Water to Move Material Scraped Off Plates to a Pulper Which Cuts Solid Waste into a Slurry
Slurry Flows From Pulper to Water Extractor Unit Which Removes Water to Produce Odor-Free, Semi-dry pulp
Extracted Water Returned to Feed Tray to Complete Closed-loop CycleWater Level Automatically ControlledSmall Amount 1-3 gpm Bled Off and ReplacedSystem Eliminates Need to Separate Food Scraps, Paper and Plastic WasteReduces Staff Time by HalfEx. POM 2 Systems, 2 Bldgs. – Cuts Daily Water Consumption from 9,240 to
1680 gallonsSavings 2.76 Million gal/year
Engineer Research and Development CenterUS Army Corpsof Engineers
SOMAT SystemPulper and Hydra-Extractor
Engineer Research and Development CenterUS Army Corpsof Engineers
Boilerless Food Steamers
• Atmospheric Compartment Food Steamers – Connected to an Incoming water Line and Utilize a Steam Boiler or Generator That Injects Steam at a Constant Rate During the Cooking Event
• To Maintain Atmospheric Pressure, Rejected Steam Goes into Drain Requiring Additional Cooling Water
• Boilerless Steamers Use a Water Reservoir in Bottom of Cooking Compartment in Lieu of a water Connection – Manual Fill and Drain. No Steam Leaves.
• Better Energy Performance and Water Efficiency• Easier Cleaning• Now About 10 Different Manufacturers• Estimate of Savings – 500-1000 gallons per day plus Energy
Savings, 3 gph vs. 20 to 40 gph
• Atmospheric Compartment Food Steamers – Connected to an Incoming water Line and Utilize a Steam Boiler or Generator That Injects Steam at a Constant Rate During the Cooking Event
• To Maintain Atmospheric Pressure, Rejected Steam Goes into Drain Requiring Additional Cooling Water
• Boilerless Steamers Use a Water Reservoir in Bottom of Cooking Compartment in Lieu of a water Connection – Manual Fill and Drain. No Steam Leaves.
• Better Energy Performance and Water Efficiency• Easier Cleaning• Now About 10 Different Manufacturers• Estimate of Savings – 500-1000 gallons per day plus Energy
Savings, 3 gph vs. 20 to 40 gph
Engineer Research and Development CenterUS Army Corpsof Engineers
Boilerless Food Steamer
Engineer Research and Development CenterUS Army Corpsof Engineers
High Efficiency Washers
• Most Are Front – Loaders
• A Few Top Loaders Marginally Meet Standard CEE (Consortium for Energy Efficiency)
• Toploaders ½ to 1/3 Price of Front Loaders
• 36% Less Water
• 60% Less Energy
• Most Are Front – Loaders
• A Few Top Loaders Marginally Meet Standard CEE (Consortium for Energy Efficiency)
• Toploaders ½ to 1/3 Price of Front Loaders
• 36% Less Water
• 60% Less Energy
Engineer Research and Development CenterUS Army Corpsof Engineers
Common Area Laundry Rooms
Study
– In-Unit Washer – 11,800 gal/year
– Common Area Laundry Rooms 3600 gal/year per Apartment
– 3.3 Times as Much Water
Why? Residents with In-Unit Washers Tend to Operate Equipment More Often and Less Efficiently
Advantages – Savings in Gas, Electricity and Sewage, Reduced Construction Expense, Increased Space in Units
Study
– In-Unit Washer – 11,800 gal/year
– Common Area Laundry Rooms 3600 gal/year per Apartment
– 3.3 Times as Much Water
Why? Residents with In-Unit Washers Tend to Operate Equipment More Often and Less Efficiently
Advantages – Savings in Gas, Electricity and Sewage, Reduced Construction Expense, Increased Space in Units
Engineer Research and Development CenterUS Army Corpsof Engineers
Hospitals
• Steam Sterilizers• Example – University of Washington• Why – Steam Sterilizers Use Cold Water to Temper
Condensate from Steam (212 F) to Keep Water Entering Drain at or Below 140 F
• Older Units – Constant Bleed of 1 gpm to Mix While Unit is Hot Including Idle Time
• Install Water Saving Kit – Device or Components That Sense Effluent Temperature and Only Apply Water When Necessary to Reduce Effluent Temperature
• Evaluation – Payback Less Than 3 months• Tests Resulted in 68 to 98% Reduction
• Steam Sterilizers• Example – University of Washington• Why – Steam Sterilizers Use Cold Water to Temper
Condensate from Steam (212 F) to Keep Water Entering Drain at or Below 140 F
• Older Units – Constant Bleed of 1 gpm to Mix While Unit is Hot Including Idle Time
• Install Water Saving Kit – Device or Components That Sense Effluent Temperature and Only Apply Water When Necessary to Reduce Effluent Temperature
• Evaluation – Payback Less Than 3 months• Tests Resulted in 68 to 98% Reduction
Engineer Research and Development CenterUS Army Corpsof Engineers
Condensate
Local Example – San Antonio
Use Air Conditioning Condensate
Free Resource – High Quality, Distilled Water
If You Can Get to the Pipe, Catch It
Typical Home 5-10 gal/day
Larger Buildings Rule of Thumb 0.1 to 0.3 gallon per ton-hour
Collect – Residential Bucket Under Drain Line
Rout to Rain Barrel or Other Collection System
Use Gravity flow
Local Example – San Antonio
Use Air Conditioning Condensate
Free Resource – High Quality, Distilled Water
If You Can Get to the Pipe, Catch It
Typical Home 5-10 gal/day
Larger Buildings Rule of Thumb 0.1 to 0.3 gallon per ton-hour
Collect – Residential Bucket Under Drain Line
Rout to Rain Barrel or Other Collection System
Use Gravity flow
Engineer Research and Development CenterUS Army Corpsof Engineers
Condensate – Cont.
• Other Buildings• Ex. 500 ton System @ 80 % Load (0.2 Factor) Produces 1.3
gpm or 56,000 Gal/Month• Case Study- San Antonio Library• Produce 1 gpm (43,200 gal/month)• Garden 26,000 square feet• Collection System – 3 Interconnected Concrete Cisterns
(8400 gal capacity)• Collect from Sump Gravity Fed into Irrigation System• Total Cost $21,500, 1/3 that of Rainwater Harvest System• Another Example - River Center Mall – 12 MG of
Condensate Used for Cooling Tower Makeup
• Other Buildings• Ex. 500 ton System @ 80 % Load (0.2 Factor) Produces 1.3
gpm or 56,000 Gal/Month• Case Study- San Antonio Library• Produce 1 gpm (43,200 gal/month)• Garden 26,000 square feet• Collection System – 3 Interconnected Concrete Cisterns
(8400 gal capacity)• Collect from Sump Gravity Fed into Irrigation System• Total Cost $21,500, 1/3 that of Rainwater Harvest System• Another Example - River Center Mall – 12 MG of
Condensate Used for Cooling Tower Makeup
Engineer Research and Development CenterUS Army Corpsof Engineers
Condensate – Cont.
Another Bldg. Captures 6.2 million gallons per year
Used for Boiler Feed Makeup water
Cost $19,000 Installed
Savings $26,000 / year
Payback – 11 Months
IOI – Possible Ordinance Mandating Collection System in New Large Buildings
Another Bldg. Captures 6.2 million gallons per year
Used for Boiler Feed Makeup water
Cost $19,000 Installed
Savings $26,000 / year
Payback – 11 Months
IOI – Possible Ordinance Mandating Collection System in New Large Buildings
Engineer Research and Development CenterUS Army Corpsof Engineers
Example Supermarket (CA)
Focus on CoolingAverage Concentration Ratio 2.45 BaselineCycles of Concentration – Approach 6, Water Reduction NegligibleProblems Scale Prevention in Condensers
Wide Range of Scale Forming MineralsCalcium Carbonate, Calcium Sulfate, Calcium Phosphate, Magnesium Silicate
Biological FoulingCorrosionTested 3 ProcessesOnly Effective Process was Alkalinity ControlOperated at 5.5 Cycles of Concentration
Focus on CoolingAverage Concentration Ratio 2.45 BaselineCycles of Concentration – Approach 6, Water Reduction NegligibleProblems Scale Prevention in Condensers
Wide Range of Scale Forming MineralsCalcium Carbonate, Calcium Sulfate, Calcium Phosphate, Magnesium Silicate
Biological FoulingCorrosionTested 3 ProcessesOnly Effective Process was Alkalinity ControlOperated at 5.5 Cycles of Concentration
Engineer Research and Development CenterUS Army Corpsof Engineers
Supermarket Cont.
BenefitsReduced Water Use, Lower Water and Wastewater ChargesReduced Electrical UseReduced Acid Washing, Life Extension of Cooling TubesB/C Ratio 2 to 4 for Water and WastewaterOther Water SavingsUse High Efficiency Spray Nozzles and Aerators on All Hand
Sinks and Spray TablesEliminate Garbage GrindersReplace Low Pressure Hoses with High Pressure Sprayers for
Washing
BenefitsReduced Water Use, Lower Water and Wastewater ChargesReduced Electrical UseReduced Acid Washing, Life Extension of Cooling TubesB/C Ratio 2 to 4 for Water and WastewaterOther Water SavingsUse High Efficiency Spray Nozzles and Aerators on All Hand
Sinks and Spray TablesEliminate Garbage GrindersReplace Low Pressure Hoses with High Pressure Sprayers for
Washing
Engineer Research and Development CenterUS Army Corpsof Engineers
Options for the Reduction of Outdoor Garden/Landscape Water
UseManagement Options Potential Savings (Percent)Turf maintenance 10Turf maintenance, irrigation system 20Maintenance, Irrigation Scheduling Mulching in Ornamental Gardens 20Soil Amendments (Compost) 20Irrigation Scheduling 25 Irrigation/Soil maintenance 65 to 75Lawn to go Dormant 90
Hardware OptionsAutoRain Shut Off 10Soil Moisture Sensors; Soil Probes 10 to 30Improve Performance 40Drip/Bubbler Irrigation 50Gray Water Up to 100Rain Barrel Catchment Up to 100
Landscape Design OptionsLandscape Design 19 to 55Turf Reduction 19 to 35Choice of Plants 30 to 80
From Gleick et al.
Management Options Potential Savings (Percent)Turf maintenance 10Turf maintenance, irrigation system 20Maintenance, Irrigation Scheduling Mulching in Ornamental Gardens 20Soil Amendments (Compost) 20Irrigation Scheduling 25 Irrigation/Soil maintenance 65 to 75Lawn to go Dormant 90
Hardware OptionsAutoRain Shut Off 10Soil Moisture Sensors; Soil Probes 10 to 30Improve Performance 40Drip/Bubbler Irrigation 50Gray Water Up to 100Rain Barrel Catchment Up to 100
Landscape Design OptionsLandscape Design 19 to 55Turf Reduction 19 to 35Choice of Plants 30 to 80
From Gleick et al.
Engineer Research and Development CenterUS Army Corpsof Engineers
New Faucet Developments
Hydropower Generator to Recharge Battery
Uses PV Cell to Power Optical Sensor
Engineer Research and Development CenterUS Army Corpsof Engineers
Summary
• Variety of Technologies and Techniques to Reduce Water Consumption
• New Resource Soon Available
– Army Water Conservation Website
– Information on Policies, Technical Guidance, Case Studies, Best Practices Within Army and Other Sectors
– Links to Information Sources
– Further Information Contact Author at 217-398-5590 or email [email protected]
• Variety of Technologies and Techniques to Reduce Water Consumption
• New Resource Soon Available
– Army Water Conservation Website
– Information on Policies, Technical Guidance, Case Studies, Best Practices Within Army and Other Sectors
– Links to Information Sources
– Further Information Contact Author at 217-398-5590 or email [email protected]