UV Disinfection Point of Use Systems - Unesco-IHE

Transcription

UV Disinfection Point of Use Systems - Unesco-IHE
UV Disinfection
Point of Use Systems:
The Good, The Bad, and The Ugly
Karl G. Linden, Ph.D.
Croft Professor of Environmental Engineering
University of Colorado Boulder, USA
UV Disinfection in Developing Countries
UNESCO-IHE and IUVA
November 6, 2014
Delft, Netherlands
Overview
 Overview of POU systems and options
 Point of Entry UV Systems
 Point of Use UV Systems
 Monitoring and Sustainability
Water Treatment in Developing Communities
• ~880 Million People Without
Access to Improved Water
Source
• No indication of water quality
• Community and Point of Use
Systems
• Many Different Options
• Boiling
• Ceramic/membrane Filters
• Biosand Filters
• Chlorine
• SODIS
• UV Treatment
Point-of-Use Options
Treatment
Chlorine
Biosand
Advantages
- Commonly used
- Available
- Residual disinfection
- Relatively fast
- No chemicals
- Removes particles
- Local materials
Ceramic
Filters
- No chemicals
- Easy to maintain
- Local materials
Boiling
- No extra materials
- Easy to integrate into
cooking
SODIS
- Can be free
- Reuses waste
UV
- No chemicals
- Effective against spores
- Fast
- Easy to verify
Disadvantages
- Toxic Chemical
- Taste & Odor issues
- DBPs
- Not effective: spores and cysts
- Slow
- Difficult to verify
- High maintenance
- No residual
- Slow
- Fragile
- Difficult to verify
- No residual
- Expensive
- Indoor air pollution
- No residual
- Slow
- Relies on sunlight
- Difficult to verify
- No residual
- Requires fairly low turbidity
- Imported materials
- No residual
Sobsey et al., 2008; Baker and Duke, 2006; Hazeltine, 2003; Clasen et al, 2008; Rainey, 2005; EPA, 2003
Applications of UV Disinfection
• Urban Setting
• Piped water supply
• No filtration needed
• Household unit
• Building unit
• Rural Setting
• Pumped or carried raw water supply to UV system
• Filtration may be needed
• Point of use for community
• Household
What Do UV Systems Look Like?
• Review point of entry systems for small communities
• Defined as serving multiple households
• Could be a community water point
• Review of point of use systems
• Defined as household or user scale
• How Sustainable are these systems?
• Elements that will increase and improve
long term effectiveness
UV Pure Technologies Inc.
Point of Entry Systems
• Community Water Points
• Schools
Bring Your Own Water (BYOW)
• Community System
• Manual System
• Roughing Filter, Gravity
Fed Sand Filter, UV
Disinfection
• Backwash
First System in Summer 2006 - Muramba
Shut down after two years
Second System in Summer 2007 – Mugonero Orphanage
Still Working with Continued Maintenance
Cost: ??
BYOW-II, August 2007
Roughing
Filter
Auto-fill
Bucket input
Backwash Tank
Rapid
Sand Filter
PV power supply
Cistern stairs
UV Disinfection unit
Manna In-Line System
• Similar to BYOW
• In-Line Filters
• Monitoring System
• Carbon Credit Financing
Model
• In place in schools and
group homes
• UV Dose ~40 mJ/cm2
Cost: ??
• Dynamic UV metering system based on flowrate (1 to 15 GPM)
• Filter bodies manufactured in Kigali
• Complete system assembled at factory in Kigali and transported to each site
Manna In-Line System
Naiade
• Flow rate: 6 liters/minute
• Lifespan of lamp: 3 years
• Monitoring: LED
indicates the status.
• UV Lamp type: 20 Watt
• UV Dose: ?
• 99% kill rate of bacteria
protozoa and viruses
Cost: $3,500
http://www.nedap-naiade.com/
AquaPure
• Flow rate: 30+ gpm
• Monitoring: ?
• UV Lamp type: ?
• UV Dose: ?
www.aquapure.com/aq-products/ultraviolet-light-systems.html
Cost: $3,599
PenTek
• Flow rate: 2 gpm
• Monitoring: ?
• UV Lamp type: LP 254 (nm)
• UV Dose: 16 mJ/cm2
Cost: $243-$573
amazon.com/Pentek-163005-UV-110-1-Ultraviolet-System/dp/B0061BODDM
HiTech Ultraviolet
• Flow rate: 7.5-50,000
LPM
• Monitoring:
• UV Lamp type: LP UV
with 185nm output
• UV Dose: 253.7nm
http://www.hitechuv.com/about-us.html
Cost: not available
UV Waterworks
• Developed at Lawrence
Berkeley National
Laboratory
• Stainless Steel and
Aluminum
• 15 liters per minute
• 40 mJ/cm2
• Serves community ~1000
• 50 Watts power
• Maintenance required
twice a year
Cost: $300-$1500*
*not available retail (aid organizations only)
UV Light in Stainless Steel Tube
Aqua Azul
Atlantic Ultraviolet Corporation
Crystal Quest
Everpure
Gowe Group
I-Spring
Minipure
Neotech Aqua Solutions
Pelican
Pentek
Polaris Scientific
Pura Purtest
Sterilight
Trojan UV Max
Vitapur
Watertec
Watts
Cost: $182-$5000
Wedeco/xylem
Point of Use Systems
• Small to very small
• Household or user scale
UV-Tube
• Household System
• $34 per system (does not
include power supply)
• 4 liters per minute
• ~90 mJ/cm2
• >4 log MS2 Removal
• Local Materials
UV Bucket/ UVeta
• Developed in Mexico
• Founder also from Berkeley
• Household System
• 3 Bucket System
• 20 liter plastic bucket
• Lab Study
• >7.5 log E. coli Removal
• 3.9 log MS2 virus Removal
• 75-85 mJ/cm2
Cost: $22
Purificador ZEOZ (Grupo EOZ)
• Flow rate: 1.5 liters/min
• Monitoring:
• UV Lamp type: (LP)
• UV Dose: ?
• Lamp life: 5,000 hours
• Reduction:
• Turbidity from 6.5 to 0.17
• Parasites: 99.99% removal
• Bacteria: 100% removal
http://agualimpia.mx/productos.php
Cost: $52-82
UV Water Box
•
•
•
•
Flow rate: 7 L/ min
UV Lamp type: LP
UV Dose: ?
Solar powered
• Kills 99% of viruses and bacteria
• Lamp life: 10,000 hours
• Solar panel 20 watt, battery 17 Ah
UV WaterBox by Aqua Aero http://www.aaws.nl/.
Cost: $3,000-$3,700
AlfaUV
• Flow rate: 2 liters/minute
• Monitoring: lamp life
indicator
• UV Lamp type: ?
• UV Dose: 30 mJ/cm2 at
90% UV Transmittance
Cost: $103
www.alfauv.com/ultraviolet-uv-products/uv-ultra-violet-water-purifier-platina
UV Pearl
• Flow rate: 2.5 gpm
• Monitoring: Power on,
PearlAqua
http://www.uvpearl.com/products.html
Lamp on, High Temp
Alarm, Low Intensity
• UV Lamp type: UV-C LED
275nm ±12nm
• UV Dose:
• Lamp life: 60,000 gallons
(270,000 litres)
Cost: Coming soon
Pureit
Cost: $134
• Flow rate: 350 ml – 750
ml/min
• Monitoring:
• UV Lamp type: 11W
• UV Dose:
• Lamp life: 3000 liters
Pureit
Cost: $341
• Flow rate: 9-12 L/hour
• Monitoring: Purity
indicator and life
indicator
• UV Lamp type:
• UV Dose:
• Lamp life: 800 hours
www.pureitwater.com/IN/
LivePur
• Flow rate: 15 liters/hour
• Monitoring:
• UV Lamp type: 11 W
• UV Dose:
www.livpurewater.com/
Cost: $277-$321
WaterFiltersFast
• Flow rate: 1-2 lpm
• Monitoring: visual
• UV Lamp type: LP 10 W
• Lamp life: 9000 hours
• UV Dose:?
Counter Top QMP605 with UV Filter System w/o filters
https://espwaterproducts.com/ManualsSpecs/QMP605-specs.pdf
Cost: $169
Steri-Pen
• Flow rate: Batch 1 L
• Monitoring: on/off timer
• UV Lamp type: LP UV
• UV Dose: >40 mJ/cm2
Cost: $50-100 USD
Camelbak Allclear
• Flow rate: Batch 1 L
• Monitoring: on/off, timer
• UV Lamp type: LP UV
• UV Dose: >40 mJ/cm2
• Shake water bottle for 1
minute
• USB Charger
• Filter add-on
www.camelbak.com/allclear
Cost: $85-100 USD
Monitoring Approaches
• UV bulb on/off indicator
• Light indicator
• UV Transmittance
• Flow Rate
• Timer on/off
• Pressure
• Remote information
• Alarm alerts for maintenance
What Makes a Good UV Device?
• Certified dose delivery – Validation conducted
• Monitoring
• Remote operation
• Ease of Maintenance
• Repairable, parts available
• Local availability of materials
• Low energy use (solar possibility)
• Germicidal UV – effective
• On-demand water (no storage needed)
Sustainability Issues
• Mercury vapor Low Pressure (LP) UV lamps
• Disposal of used lamps
• Fragile, monochromatic (254 nm)
• Efficiency ~ 35-38%
• Lifetime of ~ 9-12 months
• Replacement availability & cost
• Warm-up required
• Lamp fouling
www.maine.gov
US EPA, 2006
Promise of UV-LEDs
• Lifetime and efficiency expected to approach that of
visible LEDs (~10 years, ~75%)
• No warm-up time
• Easier to transport
• No mercury disposal issues
• Less energy loss due to heat
• Lower energy needs
• Fewer lamp fouling issues
• Specific UV wavelengths
www.maine.gov
Crawford et al., 2005; Gaska, 2007, Bettles et al., 2007
UV POU Summary
Advantages
Disadvantages
• No Taste and Odor Changes
• Need an Energy Source
• “Sexy”/Technology Factor
• Bulbs Not Available Locally
• Higher Flow Rates
• Need Additional Treatment
• No Chemical Addition
• Low Energy Need Compared
to Boiling
• Validated
for Low UVT/turbid Waters
• Mercury Disposal
• Variable dose with water
quality
• Validated?
UV Disinfection
Point of Use Systems:
The Good, The Bad, and The Ugly
Karl G. Linden, Ph.D.
Croft Professor of Environmental Engineering
University of Colorado Boulder, USA
UV Disinfection in Developing Countries
UNESCO-IHE and IUVA
November 6, 2014
Delft, Netherlands
• Karl G. Linden, Ph.D.
• karl.linden@colorado.edu