Life cycle assessment (LCA) has been proved to act as a desirable tool to evaluate the environmental
impacts of wastewater treatment plants (WWTPs). However, the application of LCA methodology in the
field of wastewater treatment is still in progress. This ppt has made a review of the LCA studies dealing
with biological (activated sludge) WWTPs, with the aim to provide qualitative interpretation of the
associated environmental impact categories: eutrophication potential, global warming potential,
toxicity-related impacts, energy balance, water use, land use and other impact categories.
Presentation at the ESPP stakeholder meeting concerning the use on farmland of sewage biosolids (04/12/2018) organised by the European Sustainable Phosphorus Platform (ESPP, www.phosphorusplatform.eu)
All outcomes of the meeting can be found here https://www.phosphorusplatform.eu/activities/conference/meeting-archive/1788-espp-meeting-sludge-2018
This is a precise Power Point presentation on Chemistry of Plastics and the main highlighted topics includes POLYETHENE. This presentation was actually made for for webinars on PLASTIC FREE MOVEMENT.
When I first started researching into Zero Liquid Discharge (ZLD), I found out that there no compact guides for this process online. This is how the idea for a ZLD booklet was born. This
rough guide is meant to help you understand the basics and to decide what’s best for your Brine Treatment case. Our Team in Lenntech B.V. will be happy to help you out with the details
and to find the best available options that will decrease the cost and increase the efficiency of
your project.
Christos Charisiadis
R&D engineer
christos@lenntech.com
September 2018
Presentation at the ESPP stakeholder meeting concerning the use on farmland of sewage biosolids (04/12/2018) organised by the European Sustainable Phosphorus Platform (ESPP, www.phosphorusplatform.eu)
All outcomes of the meeting can be found here https://www.phosphorusplatform.eu/activities/conference/meeting-archive/1788-espp-meeting-sludge-2018
This is a precise Power Point presentation on Chemistry of Plastics and the main highlighted topics includes POLYETHENE. This presentation was actually made for for webinars on PLASTIC FREE MOVEMENT.
When I first started researching into Zero Liquid Discharge (ZLD), I found out that there no compact guides for this process online. This is how the idea for a ZLD booklet was born. This
rough guide is meant to help you understand the basics and to decide what’s best for your Brine Treatment case. Our Team in Lenntech B.V. will be happy to help you out with the details
and to find the best available options that will decrease the cost and increase the efficiency of
your project.
Christos Charisiadis
R&D engineer
christos@lenntech.com
September 2018
Eco friendly technology for textile industrypreranawagh1
we should use ecofriendly technology for our textile industry as we know that textile industry is most polluted industry now. our small initial step towards Eco techniques can make biggest difference towards healthy and pure environment. give your little help for save earth, save life. i hope this presentation can influence people to move towards ecofriendly technology
Effluent Treatment Plant Design, Operation And Analysis Of Waste Water Jaidev Singh
Contents
1. Introduction to Effluent Treatment Plant (ETP)
1.1 Use of water in industries
1.2 Industrial waste water sources
1.3 Effluent Treatment Plant
1.4 National Standards for waste water
1.5 What do these standards means?
1.6 Waste water treatment
1.7 Planning an Effluent Treatment Plant : Factors to Consider
2. Treatment Methods
2.1 Physical Unit Operations
2.2 Chemical Unit Processes
2.3 Biological Unit Processes
3. Operation and control
3.1 Mixed liquor suspended solids
3.2 Sludge Volume Index and Sludge Density Index
3.3 Sludge Age; Mean Cell Residence Time (MCRT)
3.4 Food/Mass Ratio
3.5 Constant MLSS
3.6 Return Activated Sludge Control (RAS)
4. Choosing an Effluent Treatment Plant
4.1 Biological Treatment
4.2 Physico-Chemical Treatment
4.3 Physico-Chemical and Biological Treatment
4.4 Area Requirement Comparison
4.5 Cost Comparison
5. Chemical Analysis of Waste Water
5.1 Commonly used chemicals
5.2 Chemical Tests and procedures
Envirometal project and waste water treatment in pharmacuetcalteklay godefa
waste water treatment in pharmcuetical industry and envirometal impact with soluttion and preventive methods.it is actually linked with practicall and theortical and the problem that cause during waste water treatment with its solutio.it is mainly in pharmacutical industry found in adigrat town .
9. WASTE COLLECTION AND TRANSPORT.pptxRENERGISTICS
When it comes to collecting, sorting and transporting waste, a distinction is made between systematic and systemless approaches. The kirbside collection of bundled waste paper is an example of the latter. On the other hand various container systems are used for waste collection. Whereas residual waste is collected in gray containers, separate collection systems are used for a range of waste.
"Beat Plastic Pollution" is a presentation by Dr. Amrit Krishna Mitra, Assistant Professor, Department Of Chemistry, Singur Government College, West Bengal, India. In this presentation he discusses the chemistry & history of Plastics, its benefits etc., as well as the detrimental effects of plastic on the environment, and finally ways towards the resolution.
https://www.sciencesg.com/scientificity/beat-plastic-pollution/
World Environment Day is an annual event that is aimed at being the biggest and most widely celebrated global day for positive environmental action. World Environment Day activities take place all year round and climax on 5 June every year, involving everyone from everywhere.
The World Environment Day celebration began in 1972 and has grown to become one of the main vehicles through which the United Nations stimulates worldwide awareness of the environment and encourages political attention and action.
Through World Environment Day, the United Nations Environment Programme is able to personalize environmental issues and enable everyone to realize not only their responsibility, but also their power to become agents for change in support of sustainable and equitable development.
World Environment Day is also a day for people from all walks of life to come together to ensure a cleaner, greener and brighter outlook for themselves and future generations.
Everyone counts in this initiative and World Environment Day relies on you to make it happen! We call for action — organize a neighborhood clean-up, stop using plastic bags and get your community to do the same, stop food waste, walk to work, start a recycling drive . . . the possibilities are endless.
Powerful forces are driving a green economic revolution worldwide, providing in the process a strong lever for broad-based economic development in many parts of the globe, and often re-orienting national development trajectories.
South Africa, having one of the most carbon-intensive economies in the world, is no exception. Its national government is strongly committed to unleashing the potential of the green economy. This is clearly spelt out in the ‘New Growth Path’2 strategy document, which classifies the green economy as one of the ten ‘jobs drivers’. The ‘Industrial Policy Action Plan’3 in turn, encompasses strategic initiatives to develop green industries and to improve energy efficiencies. More recently, the ‘National Climate Change Response Strategy’ white paper highlighted a set of near term flagship programmes that underline the progressive transition towards a greener economy4. Importantly, the window of opportunity is quite limited and the international environment is increasingly competitive. This indicates a degree of urgency if South Africa is to succeed in the localisation drive.
Eco friendly technology for textile industrypreranawagh1
we should use ecofriendly technology for our textile industry as we know that textile industry is most polluted industry now. our small initial step towards Eco techniques can make biggest difference towards healthy and pure environment. give your little help for save earth, save life. i hope this presentation can influence people to move towards ecofriendly technology
Effluent Treatment Plant Design, Operation And Analysis Of Waste Water Jaidev Singh
Contents
1. Introduction to Effluent Treatment Plant (ETP)
1.1 Use of water in industries
1.2 Industrial waste water sources
1.3 Effluent Treatment Plant
1.4 National Standards for waste water
1.5 What do these standards means?
1.6 Waste water treatment
1.7 Planning an Effluent Treatment Plant : Factors to Consider
2. Treatment Methods
2.1 Physical Unit Operations
2.2 Chemical Unit Processes
2.3 Biological Unit Processes
3. Operation and control
3.1 Mixed liquor suspended solids
3.2 Sludge Volume Index and Sludge Density Index
3.3 Sludge Age; Mean Cell Residence Time (MCRT)
3.4 Food/Mass Ratio
3.5 Constant MLSS
3.6 Return Activated Sludge Control (RAS)
4. Choosing an Effluent Treatment Plant
4.1 Biological Treatment
4.2 Physico-Chemical Treatment
4.3 Physico-Chemical and Biological Treatment
4.4 Area Requirement Comparison
4.5 Cost Comparison
5. Chemical Analysis of Waste Water
5.1 Commonly used chemicals
5.2 Chemical Tests and procedures
Envirometal project and waste water treatment in pharmacuetcalteklay godefa
waste water treatment in pharmcuetical industry and envirometal impact with soluttion and preventive methods.it is actually linked with practicall and theortical and the problem that cause during waste water treatment with its solutio.it is mainly in pharmacutical industry found in adigrat town .
9. WASTE COLLECTION AND TRANSPORT.pptxRENERGISTICS
When it comes to collecting, sorting and transporting waste, a distinction is made between systematic and systemless approaches. The kirbside collection of bundled waste paper is an example of the latter. On the other hand various container systems are used for waste collection. Whereas residual waste is collected in gray containers, separate collection systems are used for a range of waste.
"Beat Plastic Pollution" is a presentation by Dr. Amrit Krishna Mitra, Assistant Professor, Department Of Chemistry, Singur Government College, West Bengal, India. In this presentation he discusses the chemistry & history of Plastics, its benefits etc., as well as the detrimental effects of plastic on the environment, and finally ways towards the resolution.
https://www.sciencesg.com/scientificity/beat-plastic-pollution/
World Environment Day is an annual event that is aimed at being the biggest and most widely celebrated global day for positive environmental action. World Environment Day activities take place all year round and climax on 5 June every year, involving everyone from everywhere.
The World Environment Day celebration began in 1972 and has grown to become one of the main vehicles through which the United Nations stimulates worldwide awareness of the environment and encourages political attention and action.
Through World Environment Day, the United Nations Environment Programme is able to personalize environmental issues and enable everyone to realize not only their responsibility, but also their power to become agents for change in support of sustainable and equitable development.
World Environment Day is also a day for people from all walks of life to come together to ensure a cleaner, greener and brighter outlook for themselves and future generations.
Everyone counts in this initiative and World Environment Day relies on you to make it happen! We call for action — organize a neighborhood clean-up, stop using plastic bags and get your community to do the same, stop food waste, walk to work, start a recycling drive . . . the possibilities are endless.
Powerful forces are driving a green economic revolution worldwide, providing in the process a strong lever for broad-based economic development in many parts of the globe, and often re-orienting national development trajectories.
South Africa, having one of the most carbon-intensive economies in the world, is no exception. Its national government is strongly committed to unleashing the potential of the green economy. This is clearly spelt out in the ‘New Growth Path’2 strategy document, which classifies the green economy as one of the ten ‘jobs drivers’. The ‘Industrial Policy Action Plan’3 in turn, encompasses strategic initiatives to develop green industries and to improve energy efficiencies. More recently, the ‘National Climate Change Response Strategy’ white paper highlighted a set of near term flagship programmes that underline the progressive transition towards a greener economy4. Importantly, the window of opportunity is quite limited and the international environment is increasingly competitive. This indicates a degree of urgency if South Africa is to succeed in the localisation drive.
An ecological assessment of food waste composting using a hybrid life cycle a...Ramy Salemdeeb
A conference paper published at the 8th Conference of the International Society for Industrial Ecology, At University of Surrey, Guildford, UK, At Surrey
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Sub critical water as a green solvent for production of valuable materialsGJESM Publication
gricultural waste biomass generated from agricultural production and food processing industry are abundant, such as durian peel, mango peel, corn straw, rice bran, corn shell, potato peel and many more. Due to low commercial value, these wastes are disposed in landfill, which if not managed properly may cause environmental problems. Currently, environmental laws and regulations pertaining to the pollution from agricultural waste streams by regulatory agencies are stringent and hence the application of toxic solvents during processing has become public concern. Recent development in valuable materials extraction from the decomposition of agricultural waste by sub-critical water treatment from the published literature was review. Physico-chemical characteristic (reaction temperature, reaction time and solid to liquid ratio) of the sub-critical water affecting its yield were also reviewed. The utilization of biomass residue from agriculture, forest wood production and from food and feed processing industry may be an important alternative renewable energy supply. The paper also presents future research on sub-critical water.
Sub critical water as a green solvent for production of valuable materialsGJESM Publication
Agricultural waste biomass generated from agricultural production and food processing industry are abundant, such as durian peel, mango peel, corn straw, rice bran, corn shell, potato peel and many more. Due to low commercial value, these wastes are disposed in landfill, which if not managed properly may cause environmental problems. Currently, environmental laws and regulations pertaining to the pollution from agricultural waste streams by regulatory agencies are stringent and hence the application of toxic solvents during processing has become public concern. Recent development in valuable materials extraction from the decomposition of agricultural waste by sub-critical water treatment from the published literature was review. Physico-chemical characteristic (reaction temperature, reaction time and solid to liquid ratio) of the sub-critical water affecting its yield were also reviewed. The utilization of biomass residue from agriculture, forest wood production and from food and feed processing industry may be an important alternative renewable energy supply. The paper also presents future research on sub-critical water.
Principal Tools for a Cleaner Chemical Technology, presented at the european ...Patrick VanSchijndel
Principal Tools for a Cleaner Chemical Technology, Process improvements have been tremendous in the last century but production volume increase will overshadow these good results in terms of resource use and environmental impact. It will be important to use the right tools in order to achieve the necessary sustainable development within the industry. These tools should be combinations of exergy analysis, LCA and economic analysis. The focus should be on the development of these combinations and on the teaching of these combinations in engineering curricula.
Artificial Reefs by Kuddle Life Foundation - May 2024punit537210
Situated in Pondicherry, India, Kuddle Life Foundation is a charitable, non-profit and non-governmental organization (NGO) dedicated to improving the living standards of coastal communities and simultaneously placing a strong emphasis on the protection of marine ecosystems.
One of the key areas we work in is Artificial Reefs. This presentation captures our journey so far and our learnings. We hope you get as excited about marine conservation and artificial reefs as we are.
Please visit our website: https://kuddlelife.org
Our Instagram channel:
@kuddlelifefoundation
Our Linkedin Page:
https://www.linkedin.com/company/kuddlelifefoundation/
and write to us if you have any questions:
info@kuddlelife.org
WRI’s brand new “Food Service Playbook for Promoting Sustainable Food Choices” gives food service operators the very latest strategies for creating dining environments that empower consumers to choose sustainable, plant-rich dishes. This research builds off our first guide for food service, now with industry experience and insights from nearly 350 academic trials.
Natural farming @ Dr. Siddhartha S. Jena.pptxsidjena70
A brief about organic farming/ Natural farming/ Zero budget natural farming/ Subash Palekar Natural farming which keeps us and environment safe and healthy. Next gen Agricultural practices of chemical free farming.
Diabetes is a rapidly and serious health problem in Pakistan. This chronic condition is associated with serious long-term complications, including higher risk of heart disease and stroke. Aggressive treatment of hypertension and hyperlipideamia can result in a substantial reduction in cardiovascular events in patients with diabetes 1. Consequently pharmacist-led diabetes cardiovascular risk (DCVR) clinics have been established in both primary and secondary care sites in NHS Lothian during the past five years. An audit of the pharmaceutical care delivery at the clinics was conducted in order to evaluate practice and to standardize the pharmacists’ documentation of outcomes. Pharmaceutical care issues (PCI) and patient details were collected both prospectively and retrospectively from three DCVR clinics. The PCI`s were categorized according to a triangularised system consisting of multiple categories. These were ‘checks’, ‘changes’ (‘change in drug therapy process’ and ‘change in drug therapy’), ‘drug therapy problems’ and ‘quality assurance descriptors’ (‘timer perspective’ and ‘degree of change’). A verified medication assessment tool (MAT) for patients with chronic cardiovascular disease was applied to the patients from one of the clinics. The tool was used to quantify PCI`s and pharmacist actions that were centered on implementing or enforcing clinical guideline standards. A database was developed to be used as an assessment tool and to standardize the documentation of achievement of outcomes. Feedback on the audit of the pharmaceutical care delivery and the database was received from the DCVR clinic pharmacist at a focus group meeting.
"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...MMariSelvam4
The carbon cycle is a critical component of Earth's environmental system, governing the movement and transformation of carbon through various reservoirs, including the atmosphere, oceans, soil, and living organisms. This complex cycle involves several key processes such as photosynthesis, respiration, decomposition, and carbon sequestration, each contributing to the regulation of carbon levels on the planet.
Human activities, particularly fossil fuel combustion and deforestation, have significantly altered the natural carbon cycle, leading to increased atmospheric carbon dioxide concentrations and driving climate change. Understanding the intricacies of the carbon cycle is essential for assessing the impacts of these changes and developing effective mitigation strategies.
By studying the carbon cycle, scientists can identify carbon sources and sinks, measure carbon fluxes, and predict future trends. This knowledge is crucial for crafting policies aimed at reducing carbon emissions, enhancing carbon storage, and promoting sustainable practices. The carbon cycle's interplay with climate systems, ecosystems, and human activities underscores its importance in maintaining a stable and healthy planet.
In-depth exploration of the carbon cycle reveals the delicate balance required to sustain life and the urgent need to address anthropogenic influences. Through research, education, and policy, we can work towards restoring equilibrium in the carbon cycle and ensuring a sustainable future for generations to come.
Characterization and the Kinetics of drying at the drying oven and with micro...Open Access Research Paper
The objective of this work is to contribute to valorization de Nephelium lappaceum by the characterization of kinetics of drying of seeds of Nephelium lappaceum. The seeds were dehydrated until a constant mass respectively in a drying oven and a microwawe oven. The temperatures and the powers of drying are respectively: 50, 60 and 70°C and 140, 280 and 420 W. The results show that the curves of drying of seeds of Nephelium lappaceum do not present a phase of constant kinetics. The coefficients of diffusion vary between 2.09.10-8 to 2.98. 10-8m-2/s in the interval of 50°C at 70°C and between 4.83×10-07 at 9.04×10-07 m-8/s for the powers going of 140 W with 420 W the relation between Arrhenius and a value of energy of activation of 16.49 kJ. mol-1 expressed the effect of the temperature on effective diffusivity.
UNDERSTANDING WHAT GREEN WASHING IS!.pdfJulietMogola
Many companies today use green washing to lure the public into thinking they are conserving the environment but in real sense they are doing more harm. There have been such several cases from very big companies here in Kenya and also globally. This ranges from various sectors from manufacturing and goes to consumer products. Educating people on greenwashing will enable people to make better choices based on their analysis and not on what they see on marketing sites.
DRAFT NRW Recreation Strategy - People and Nature thriving together
Life Cycle Assessment of Wastewater Treatment Plant.pptx
1. Presented By Abdul Sami
Research Paper assigned by Dr. Sheeraz
Institute of Energy, Environmental
Engineering & Management
Mehran
University
of Engineering
& Technology
Jamshoro
2. Black water has come
into contact with fecal
matter. Fecal matter is a
haven for
harmful bacteria and
disease-
causing pathogens.
Gray water, on the
other hand, has not
come into contact with
solid human waste
Storm water, That
comes from Storms
and Rain
3. Life Cycle Assessment
• assessing the impacts on
human health and the
environment associated with
energy and raw material and
environmental releases.
• evaluating opportunities to
reduce energy, material
inputs, or environmental
impacts at each stage of the
product life-cycle.
• quantifying the energy and
raw material inputs and
environmental releases
associated with each stage of
production
• purpose and the expected
products of the study, and
determining the boundaries
(what is and is not included in
the study)
Goal
definition and
scoping
Life-cycle
inventory
Impact
analysis
Improvement
analysis
6. A b s t r a c t (Improved) Total words 198
A review of the LCA studies dealing with biological (activated sludge) WWTPs has been made, to provide
qualitative interpretation of the associated environmental impact categories: eutrophication potential, global
warming potential, toxicity-related impacts, energy balance, water use and land use. Possible sources for each
impact category of WWTPs are summarized in order to provide information about the critical aspects in WWTP
systems that might influence LCA results. Moreover, recent development and the application status of
characterization models for each impact category have been reviewed. Due to specificity of the eutrophication
potential and toxicity-related impact categories, need implementation and site-specific LCA studies are
suggested, considering the emission location and properties of pollutants. While obtaining the remarkable
progress, still applications in the field of WWT are limited. For the global warming potential impact category, it is
most crucial to calculate accurately the greenhouse gas (GHG) emissions, because nitrous oxide (N2O) and
methane (CH4), as well as fossil origin carbon dioxide (CO2) in wastewater have the potential to make
considerable contributions. In the end, prospective is made about which aspects in WWTPs are candidates for
further LCA studies. Overall, there is still room for pursuing more accurate results when applying LCA to WWTPs.
7. • The environmental issue is now recognized as one of the major
concerns in many proposed projects (Dennison et al., 1998).
• Wastewater treatment plants (WWTPs) have been designed and
operated to reduce the pollution of wastewater produced by human
activities in order to minimize the negative influences on
environmental quality and human health (Wang et al., 2012).
• WWTPs bring many other adverse environmental impacts at the same
time due to material and energy consumption, various emissions to
environment, as well as the generated sludge which requires
additional treatment (Hospido et al., 2004).
8. • Thus, to achieve the objective of true sustainability, the
environmental impacts of WWTPs should not exceed the benefits of
remediation.
• Need of assessment from an integrated perspective.
• Several reviews on LCA studies dealing with WWTPs have been
published.
• Recently, following LCA methodological steps (Corominas et al.
(2013b) have taken a comprehensive analysis of LCA studies on
wastewater treatment, trying to identify what had been achieved and
depict the challenges for the future.
9.
10.
11. • Nevertheless, it is noted that no review is specifically conducted to
investigate the Results of WWTP-related LCA studies, on a
comprehensive scale.
• Therefore, this paper tries to fill this gap by summarizing a large
portion of the existing scientific literatures that explicitly use LCA
methodology, or a life-cycle approach, to assess the environmental
impacts of WWTPs.
12.
13. Method
upstream processes
Comprise wastewater collection
and transport to the plant.
Core processes
include the plant construction,
operation (energy consumption
for treatment steps,
manufacture of chemicals and
maintenance material, resources
consumption and the handling of
process-related emissions and
waste, etc.)
Downstream processes
Represent the production of by-
products (e.g. electricity/heat by
biogas, residuals to recycling).
Product
Category
Rules
(PCR)
• It is noted that lots of WWTP-related LCA studies (Table 1) have expanded their system boundaries to include downstream
processes, i.e. material substitution (replacement of potable water by wastewater reuse; fertilizer production avoided by
agricultural application of sludge) or energy recovery (energy production avoided by biogas from anaerobic digestion or
incineration of sludge). we specifically focus on LCA studies best corresponding to wastewater treatment, with the main
attention being paid to biological (activated sludge) wastewater treatment technologies.
14. Input and Outputs of a Core Stream Process
wastewater
Energy
chemicals
Various emissions to the
surrounding environment, i.e.
water (mainly due to wastewater
effluent), air (CO2, CH4 and so on)
and soil (mainly due to agricultural
application or landfill of sludge,
irrigation of treated wastewater
and so on)
15. • Several researchers have focused on comparing conventional wastewater
treatment technologies with source-separation wastewater treatment
systems, which treat separately domestic sewage depending on different
sources (i.e. black and gray water)
• The benefits are related to limiting nutrient emissions to aquatic
environment (because nutrients have been separated from wastewater)
and preventing toxic substances to agricultural land (since fertilizer use has
been avoided).
• However, other environmental impacts, e.g. ammonia emissions from
digestate (i.e. anaerobic digestion of black water), emissions from multiple
infrastructure for source separating systems might impose challenges on
the application of source separation systems
16.
17. Eutrophication
• The process by
which a body of
water becomes
enriched in
dissolved nutrients
(as phosphorus &
nitrogen) that
stimulate the
growth of aquatic
plant life usually
resulting in the
depletion of
dissolved oxygen
18. Eutrophication Potential
• Nutrients in the effluent has been considered the most relevant
environmental issue when performing environmental evaluation of
WWTPs.
• impact can be decreased immediately by implementing more
sophisticated technology to enhance the nutrient removal efficiency
• it is realized by an increasing number of researchers that today's WWTPs
LCA, which focuses on what must be removed from wastewater, should be
shifted to a new one focusing on what can be recovered
• It is reported that freshwater eutrophication is more cause by (P) emissions
in effluents whereas the Marine eutrophication is more caused by Nitrogen
19. Global warming potential
• Gradual increase in the overall temperature of the earth's
atmosphere generally attributed to the greenhouse effect caused by
increased levels of CO₂, N₂O, and other pollutants.
Direct Emissions
N2O generated from secondary
biological wastewater treatment
(denitrification)
CH4 from the anaerobic wastewater
and/or sludge treatment process.
CO2 emissions from (aerobic
biodegradation) treatment process
Indirect Emissions
GHG emissions mainly stem from
the production of electricity and
chemicals used in WWTPs,
transportation of fuel, chemicals
and wastes, degradation of
remaining constituents in the
effluent and sludge receiving
environment
20. Global warming potential
• recently found that emissions of N2O (mainly from water line) are the
most significant contributors, about 3 times more important than
electricity use.
• The dominant role of N2O in direct GHG emissions is also discovered.
• Although results from different LCA studies vary with different
assumptions, these conclusions remind us that more consideration
should be paid to N2O emissions in WWTPs.
• However, large uncertainties are associated with the emission
estimation is due to the difficulty of identifying the prominent
mechanism of wastewater nitrification-denitrification process (Foley
et al., 2010b). Numerous efforts have been made to quantify the N2O
emissions more accurately.
21. Toxicity-related impact categories
• Large discrepancies in toxic impact categories are observed.
• It has been pointed out that the differences between LCIA methods
regarding the toxicity impacts mainly lie in the phase of
characterization;
• inclusion/exclusion of specific substances.
• when comparing different LCIA methods, great distinction is found
regarding the toxic ranking of pollutants.
• Therefore, further LCA studies need to investigate whether or not the
potential impacts on ecosystems and human health are actually
reduced.
22. Conclusion
• This paper has analyzed LCA studies dealing with WWTPs, which are based on
biological (activated sludge) technologies. LCA is generally used by researchers for
comparing and optimizing the WWTP systems, as well as the resource and energy
recovery alternatives.
• Efforts have also been made to investigate further development of some specific
impact categories in the field of wastewater treatment.
• Although many variables are involved in LCA results, this paper has provided
qualitative interpretation for the associated environmental impact categories.
• The possible sources for each impact category of WWTPs are summarized in
order to provide information about the critical aspects in WWTP systems that
might influence the LCA results.
• Moreover, recent development and the application status of characterization
models for each impact category has been reviewed.
• We can deduce that the most important issue is to carry out site-specific LCA
studies on WWTPs.