IWA World Water Congress
10 -14 September 2006
Beijing, China
M. Fujiwara, ◎N. Hayashi, K. Kanai, M. Kiyozuka, (Japan Water
Research Center); Y. Matsui, (Hokkaido University); K. Mori, (Ebara
Corporation); Y. Sakakibara, (Nihon Suido Consultants Co., Ltd)
Application of Life Cycle Assessment (LCA)
to Water Purification Facilities
Introduction
Water purification: Conventional ⇒ “Coagulation
Sedimentation & Sand Filtration”
Newly ⇒ “Membrane Filtration ”, a measure against
Cryptosporidium
Water supply facilities need a great amount of energy.
A few cases in Japan in which a purification process
was selected by considering the environmental loads.
I present a case study in which inventory analysis, as
an element of life cycle assessment (LCA), choosing
from the two alternatives processes.
Background
Selection of purification process involves such conventional
indexes as treatability, maintainability or cost:
⇒Very conventional approach
Quantitative identification and evaluation of environmental
impact ⇒Insufficient
Establishment of a research technique of a purification
plant considering reduction of environmental loads
Being worked on under the e-Water project
Background
What is e-Water ?
„Environmental, Ecological, Energy-saving and
Economical Water Purification System
„ Researcher: Japan Water Research Center
„ Subsidization: Ministry of Health, Labour and Welfare
„ Participants: Academia, Waterworks Utilities, and Private
companies
„ Research Cost: $ 6 Million
„ Research Period: fiscal 2002-2004
)
Detailed Info: go to Poster Gallery, Poster No.27
Scope of Research
Scope：Purification Plant: Construction Stage - Operation Stage
Construction Stage
Procurement and
Construction
Fabrication and
Assembly
Operation Stage
Used as Purified Water
Power, Fuel and Chemicals
Scope of Research
Items：Life Cycle Energy Consumption (LC-E)
Life Cycle CO2 Emissions (LC-CO2 )
Disposal Stage
Demolition and
Disposal
Future Tasks
Scope of Research
Typical Rapid Filtration
Coagulant and Chlorine
Chlorine
Raw
Water
Water
Receiving
Basin
Coagulation
Sedimentation Basin
Sludge
Returned
Water
Supernatant
Rapid
Filtration
Basin
Clean Water
Reservoir
Purified
Water
Sludge
Settling
Basin
Discharging
Basin
Thickening
Tank
Sludge
Dehydrator
Supernatant
To water
Distribution
Administration Building
and Electric
Instrumentation
Equipment
To Disposal of
Sludge
Scope of Research
Raw
Water
Water
Receiving
Basin
Coagulant and
Chlorine
Coagulation Basin
Administration Building
and Electric
Instrumentation
Equipment
Membrane
Filtration
Sludge
Dehydrator
Membrane Filtration
Chlorine
Clean water
Reservoir
To Water
Distribution
To Disposal
of Sludge
Structuring of Scope of Research
Operation
Construction
Major Sector
Classification
Civil
Engineering
Mechanical
Equipment
Electric
Equipment
Building
Small
Classification
Detailed
Classification
Water
Receiving
Basin
Building
Frame
Reinforced Concrete
Casting (21-8-25)
Sedimentation Basin
Pipes/
Valves
Middle
Classification
・ ・ ・ ・ ・
Paddled Short Pipes
(φ600×1,000)
・ ・ ・ ・ ・
Filtration
Basin
Earthwork
・ ・ ・ ・ ・
・ ・ ・ ・ ・
Excavation and
Machines
・ ・ ・ ・ ・
990 items
Calculation Conditions and Method
6
6
6
6
6
6
Purification Treatment Flow
Coagulation Sedimentation ＋ Sand Filtration （typical flow, based on
an actual plant), Membrane Filtration (virtual plant)
Treatment Capacity
20,000 m3/d (av. treatment capacity of Rapid Filtration in Japan)
Characteristics of Purification Plant
Gravity flow from water receiving basin to clean water reservoir
Scope of Research
Construction and operation stage of facilities and equipment in the plant
⇒ Energy and CO2
Research Method →LCA ⇒ Unit Process Analysis
Embodied Intensities (Basic Unit)
Values taken from existing literature (e.g. 3EID) are mainly used
LC-E and LC-CO2 Calculation Sample
Calculated using the basic units for concrete of temporary plant
♨
Energy：
562m3×2,020.2MJ/m3=1,135,352MJ
♨
CO2：
562m3×62.97kg-c/m3=35,389kg-C
♨
The same calculation method is used for other items
‹ Life Cycle Period
To convert energy consumption and CO2 emissions to an annual total:
‹
‹
‹
‹
Civil engineering structures: 60 years
Mechanical equipment: 15 years
Electric equipment: 20 years
Building utilities: 50 years
Results of Research
Operation
(mechanical)
19%
LC-CO2 of Major
Sector Classification
Construction
(civil engineering)
35%
Operation
(electric)
14%
Construction
9% Construction
(building)
3%
(mechanical)
20%
Construction
(electric)
Results of Research
LC-CO2 of Major
Sector Classification
Construction (civil
engineering)
Operation
(mechanical)
45%
Construction
(mechanical)
44%
Construction
Operation
6% (electric)
(electric) Construction
5%
(building)
Results of Research
Life Cycle CO2
Construction stage
‹Coagulation Sedimentation + Sand Filtration 67％
‹Membrane Filtration
50％
Operation stage
‹Coagulation Sedimentation + Sand Filtration
⇒ Mechanical ＋ Electric
‹Membrane Filtration ⇒ Mechanical
Results of Research
Operation
(mechanical)
31%
LC-E of Major Sector
Classification
Construction
(Civil engineering)
18%
Construction
(mechanical)
33%
Construction
(mechanical)
5%
3%
Construction
(electric)
Operation
(electric)
24%
Construction
(building)
19%
Operation
(mechanical)
57%
Construction
6% (building)
4%
Operation
(electric)
Results of Research
Life Cycle Energy
Construction stage
Coagulation Sedimentation + Sand Filtration 45％
Membrane Filtration
37％
Operation stage
Coagulation Sedimentation + Sand Filtration
mechanical＋electric
Membrane Filtration
mechanical
Results of Research
LC-E Analysis for Middle
Sector Classification Items
Membrane Filtration
Rapid Filtration
Improvement work in the
compound
Substation
Land development work
Standby generator
Monitoring control
and instrumentation
Substation
Power and control
Monitoring control and
instrumentation
Power and control
Administration
building
Administration building
On-site piping
Membrane module
Dehydrator
Membrane filtration
facility
Discharging basin and
thickening tank
Clean water reservoir
Chemical feeding
equipment
Sedimentation basin and
filtration basin
Chemical mixing
tank
Chemical feeding
equipment
Chemical mixing tank
MJ / Y / m3
Water receiving
basin
MJ / Y / m3
Conclusions
LC-E and LC-CO2 for the life cycle of a water
purification plant (materials, construction, operation
and maintenance) were calculated by applying LCA.
LC-E and LC-CO2 of the Membrane Filtration facility
is highly likely to be equal to that of the conventional
Coagulation Sedimentation + Sand Filtration facility.
The calculation results were obtained under special
prerequisites; they will vary depending on the
calculation conditions.
Thank you for your attention.