Yes / Developing a fast, cost-effective, eco-friendly solution to recycle large amounts of construction and demolition waste (CDW) generated from construction industry-related activities and natural disasters is crucial. The present investigation aims to offer a solution for repurposing CDW into building materials suitable for accelerated construction and housing in developing countries and disaster-prone areas. Feasibility of recycled concrete aggregate (RCA) inclusion in geopolymer mortars constituted entirely from CDW (masonry elements) was investigated via an environmental impact-oriented approach by addressing the composition related key parameters. Mechanical performance was evaluated through compressive strength tests, and scanning electron microscope (SEM) imaging with line mapping analyses were carried out to monitor the interfacial transition zone (ITZ) properties. To investigate the environmental impacts of the geopolymer mortars and highlight the advantages over Portland cement-based mortars, a cradle-to-gate life cycle assessment (LCA) was performed. Findings revealed that roof tile (RT)-based geopolymer mortars mainly exhibited better strength performance due to their finer particle size. Mixtures activated with 15 M NaOH solution and cured at 105 °C achieved an average compressive strength above 55 MPa. RCA size was the most influential parameter on compressive strength, and a smaller maximum RCA size significantly increased the compressive strength. Microstructural analyses showed that the ITZ around smaller RCAs was relatively thinner, resulting in better compressive strength results. LCA proved that CDW-based geopolymer mortars provide the same compressive strength with around 60% less CO2 emissions and similar energy consumption compared to Portland cement-based mortars. / This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 894100. The authors also wish to acknowledge the support of the Scientific and Technical Research Council of Turkey (TUBITAK) provided under project: 117M447

Sustainability and specifically environmental stewardship are emerging as prominent issues in engineering decision-making. Despite this, the United States has neither a national policy on sustainability, nor a national sustainable transportation strategy. In many cases this has resulted in state DOTs basing their environmental practices on requirements set out previously by EPA regulations with little or no additional consideration of environmental effects. A survey conducted as part of this thesis revealed that environmental stewardship is not considered part of current DOT pavement management engineers' job responsibilities, despite having duties such as pavement design and maintenance which can greatly affect the environmental impact of a project. Initial cost and engineering judgment were the most widely considered in decision-making, with LCCA also being considered at least some of the time by most respondents. Environmental impacts, on the other hand, are not often integrated into formal decision making and are more likely to be considered as a "tie breaker" when alternatives have similar costs. The literature review also covered two distinct types of environmental decision support tools: Environmental Rating Tools and Environmental Impact Calculators. Rating Tools gather predominantly environmental impact information in order to award a score to a project. Environmental Calculators are software tools that use material or equipment inputs to estimate the amount of pollutants produced by a project. While a variety of environmental impact tools are currently available they suffer from drawbacks such as incomplete or unclearly defined LCA boundaries, consideration of only one environmental impact, subjectivity, lack of transparency, out-of-date databases, and an inability to perform probabilistic calculations. CO₂e was the only environmental factor considered by nearly all Environmental Calculators reviewed as part of this thesis and was a major focus of the Rating Tools. The thesis proposes the framework for a tool that addresses some of the limitations of available tools and aids decision-makers in incorporating environmental factors into roadway decision-making. The proposed tool would address many of the limitations of previous environmental impact calculators and could be implemented without the need for extensive additional research. The tool would calculate emissions due to material extraction and production, emissions due to construction activities, resource consumptions, and emissions due to work zone delays. Emissions due to work zone delays are not considered by any other currently available tool. The tool would also perform probabilistic calculations and have a database which could be added to and updated by users. Additional products developed as part of this thesis are a review of currently available environmental impact tools and a Microsoft Excel workbook used to demonstrate the intended usage of the tool. It is concluded that the development of such a tool is necessary and feasible. The proposed tool would address limitations of available tools by considering more than one environmental impact, including the previously neglected impact of emissions due to work zone related delay, pairing a user-friendly interface with an editable database, and supporting probabilistic calculations. Recommended future research includes surveying state DOT engineers to determine the barriers delaying implementation of currently available environmental impacts tools. Further benefits could be realized by programming the proposed tool and building a database that reflects the materials, mixes, and construction activities available to a specific locality. / Master of Science

Globally, the rising extraction of raw materials results in substantial resource depletion. The global circularity rate declines yearly as goods manufacturing consumes energy, fossil fuels, and primary materials. In the EU, about 11 million tonnes of furniture are discarded annually, and most end up in landfills. Sweden discards about 330.000 tonnes of office furniture each year. Sharing and reusing with Circular Economy (CE) strategies can possibly reduce environmental impact, yet challenges may arise from extra measures and expectancies when sharing. There are few studies that assess CE strategies in the use phase and environmental impacts of furniture. For the evaluation of CE strategies and a product's potential environmental impact and comparing user scenarios, this study used a Life Cycle Assessment (LCA). The goal is to explore under what circumstances height adjustable desks (desks) in four user scenarios (baseline scenario and three scenarios with adopted CE strategies for closing, slowing, and narrowing the material loops) are the most beneficial for the environment. The evaluation is conducted by analysing the scenario’s potential impact (i.e., midpoint categories GWP, HNCT and MRS). The results show that the manufacturing of the desk frame has a significant impact in the midpoint categories GWP and MRS, and the manufacturing of the motor in the midpoint category HNCT, in all four scenarios. The rental scenario, with high utilisation (80%) due to flexibility, has the lowest potential impact, compared to the three other scenarios with 40% utilisation. Two sensitivity analyses were conducted, which showed that the utilisation rate and lifespan of parts (due to aesthetic expectations) is crucial for what scenario that has the best outcome. Rental and reuse have a lower impact compared to recycling and baseline. The circumstances of high utilisation rate and flexibility benefitted the rental scenario. Product design strategies such as modular, easy repair and maintenance, and the original equipment manufacturer (OEM) keeping ownership or agreeing with the user are critical for substituting parts in the reuse and rental scenarios. This study shows that renting office desks is the best option, compared to the other scenarios, as long as utilisation is over 54% and high user expectations do not demand new desktops every 5th year.

Life Cycle Assessment (LCA) is a widely used method to assess the environmental impacts of a products entire value-chain. However, LCA currently falls short in incorporating biodiversity impacts. This study aims to evaluate different biodiversity assessment methods in regards to what biodiversity aspects they can address, how compatible the methods are with LCA, as well as how relevant they are for wind power production during use-phase. A literature review identified three different methods: InVEST Habitat Quality Model, Landscape Assessment Protocol and Species Distribution Modeling, which were then selected for further evaluation. The criteria-based evaluation shows that the three methods address multiple aspects of biodiversity, including those not addressed in contemporary LCA methods. Furthermore, the evaluation reveals a number of challenges in regards to their compatibility with the LCA-framework. To conclude, this study reveals that finding biodiversity assessment methods that can be incorporated into LCA is difficult without changing the format of how the results from the method is presented. / Livscykelanalys (LCA) är ett verktyg som används för att bedöma den miljöpåverkan en produkt har genom hela produktkedjan. I dagsläget finns det brister i hur LCA bedömer vissa aspekter av biodiversitet. Bland annat har LCA idag inte möjlighet att bedöma alla av de fem direkta faktorerna som leder till förlust av biologisk mångfald. Denna studie syftar till att utvärdera olika metoder som bedömer biodiversitet med hänsyn till vilka aspekter av biodiversitet de kan bedöma, hur väl de kan integreras i LCA, samt hur relevanta de är för bedömning av vindkraftens påverkan på biodiversitet under användarfasen. Genom en litteraturstudie identifierades tre metoder som valdes ut för vidare utvärdering, nämligen InVEST Habitat Quality Model, Landscape Assessment Protocol och Species Distribution Modeling. En lista med 14 kriterier skapades för att utvärdera metoderna. Dessa kriterier lyfter vilka aspekter av biodiversitet metoderna kan bedöma, huruvida de är kompatibla med ramverket för LCA, samt vilka styrkor eller brister de besitter utifrån ett metodiskt perspektiv. Utvärderingen visade att metoderna kan bedöma flera aspekter av biodiversitet som inte tas upp i redan etablerade LCA-metoder. Utvärderingen synliggjorde även flera utmaningar i metodernas kompatibilitet med ramverket för LCA. Sammanfattningsvis visar denna studie att det är en utmaning att hitta metoder som bedömer biodiversitet och som även kan integreras i LCA utan att det krävs förändringar i hur resultaten presenteras.

The incentives and policies spearheaded by the U.S. government have created abundant opportunities for renewable fuel production and commercialization. Bio-butanol is a very promising renewable fuel for the future transportation market. Many efforts have been made to improve its production process, but seldom has bio-butanol research discussed the integration and optimization of a cellulosic bio-butanol supply chain network. This study focused on the development of a physical supply chain network and the optimization of a green supply chain network for cellulosic bio-butanol. To develop the physical supply chain network, the production process, material flow, physical supply chain participants, and supply chain logistics activities of cellulosic bio-butanol were identified by conducting an onsite visit and survey of current bio-fuel stakeholders. To optimize the green supply chain network for cellulosic bio-butanol, the life cycle analysis was integrated into a multi-objective linear programming model. With the objectives of maximizing the economic profits and minimizing the greenhouse gas emissions, the proposed model can optimize the location and size of a bio-butanol production plant. The mathematical model was applied to a case study in the state of Missouri, and solved the tradeoff between the feedstock and market availabilities of sorghum stem bio-butanol. The results of this research can be used to support the decision making process at the strategic, tactical, and operational levels of cellulosic bio-butanol commercialization and cellulosic bio-butanol supply chain optimization. The results of this research can also be used as an introductory guideline for beginners who are interested in cellulosic bio-butanol commercialization and supply chain design. / Ph. D. / Renewable energy is one of the most effective tools to fight the threats of climate change, global warming, food price rising, and energy dependence. Cellulosic bio-butanol, a renewable alcohol-based biofuel, is a very promising energy candidate to support the fight for these threats. Due to its low water miscibility, similar energy content and octane number with gasoline, blending ability with gasoline in any proportions, and its directly utilization in gasoline engine, cellulosic bio-butanol is a potential candidate to replace gasoline. Unlike bioethanol, which only relies its fuel distribution on railway and tanker trucks, bio-butanol is compatible with not only railway and tanker trucks but also current pipeline based fuel distribution infrastructures. In order to increase the competitively of this promising energy candidate, the cellulosic bio-butanol is worth to be commercialized. An important step for the commercialization of cellulosic bio-butanol is the network design of its supply chain. In this research, the supply chain network of cellulosic bio-butanol was constructed and optimized. The supply chain network of cellulosic bio-butanol was constructed by identifying the three important aspects of a supply chain network structure: structure dimension, participants in supply chain, and supply chain business process links. A) The structure dimension was identified by understanding the production process of bio-butanol. A case study was used to study the production process of cellulosic bio-butanol. B) The supply chain business process links were identified by conducting a survey on the logistics activities in bio-butanol supply chain. C) The participants of cellulosic bio-butanol supply chain were identified by identifying the physical infrastructure of cellulosic bio-butanol supply chain. The results of the literature review, case study and survey were analyzed to identify the physical infrastructure and the participants in the supply chain. It was found out that the supply chain network structure of cellulosic bio-butanol includes 4 tiers of horizontal structure: suppliers, producers, distributors, and customers. The suppliers refer to the local farmers and feedstock aggregators. The producers are the cellulosic bio-butanol production plants. The distributors are the fuel logistics companies and fuel distributors. The customers are the fuel companies. The cellulosic bio-butanol producers use contracts to connect with biomass suppliers, fuel distributors, and bio-butanol customers. Based on the proposed network structure of cellulosic bio-butanol supply chain, the optimization of the green cellulosic bio-butanol supply chain network was conducted. A multi-objective linear integer programming model was developed to design the green cellulosic bio-butanol supply chain network. Life cycle analysis (LCA) and net present value techniques were used in the proposed model to formulate the environmental and economic objective function. With the objectives of maximizing the economic profits while minimizing the greenhouse gas (GHG) emissions, the proposed model can optimize the location and the size of bio-butanol production plant. The model was applied using data from the state of Missouri (MO). The results showed that the optimal location of cellulosic bio-butanol production plant is in the southeastern region of MO. And the production size of bio-butanol production plant is based on the tradeoff between the economic and environmental objectives. The lower GHG emissions results in a smaller size of production plant.

Sustainability is one of the most critical issues in today's packaging and supply chain industries. With the increase of environmental concerns, there has been a tremendous effort to improve packaging sustainability. However, most of these works have focused on individual packaging components rather than an integrated unit load. In global supply chains, three levels of packaging components (primary, secondary, and tertiary) are commonly assembled in the unit load form to facilitate efficient and economical storage and transport of goods to customers. Unit loads is important to improved, packaging sustainability. This study developed the fundamental information that facilitates understanding and enhanced sustainability of unit loads from two different perspectives: physical interactions and end-of-life options of unit load components. From the physical interaction perspective, the effects of various characteristics of secondary and tertiary packaging components on load-bridging within unit loads are investigated.. Packaging component characteristics investigated included the flute type and size of corrugated paperboard boxes, stretch wrap containment force, and pallet stiffness. From the end-of-life option perspective, process methods and environmental impacts of wood pallet repair in the United States are analyzed to provide fundamental information for accurate life cycle assessment of pallets. The experimental results of this study demonstrate that the size of corrugated paperboard boxes and stretch wrap containment force significantly affected the bridging of loads on pallets. The results regarding load-bridging, verified in this study, provides essential knowledge regarding factors influencing unit load deflection. Pallet design procedure should include the load-bridging effect. For simulated pallets which was comparable to a stringer class wood pallet spanning the width of a storage rack, average deflection in the unit load decreased by 70% when package size increased to 20 in. x 10 in. x 10 in. from 5 in. x 10 in. x 10 in. In addition, average deflection in the unit load consisting of 5 in. x 10 in. x 10 in. packages decreased by 50% when stretch wrap containment force increased to 30 lbs. from zero pounds. Updated design methods that consider the effect of packaging characteristics on unit load deflection can help to reduce the amount of raw materials required to build pallets using current pallet design methodologies. The life cycle inventory analysis results of this study determined that pallet repair is an environmentally beneficial end-of-life option for 48 by 40- inch stringer class wood pallets in terms of greenhouse gas generation. Most wood pallet repair firms in the United States utilized high levels of manual labor with non-automated machinery support. The life cycle inventory results from this study can be a useful resource for researchers as an input to the life cycle assessment. / Ph. D.

Sustainability is increasingly becoming a significant part of strategic asset management worldwide. Road agencies are providing guidelines to assess the relative sustainability of road projects. Unfortunately, environmental features of a road project are still considered as stand-alone evaluations, an added value. Very little has been done to integrate environmental impacts as a part of pavement management systems and other decision support tools to choose between different strategies. In this way, being awarded with a "green" certificate for a specific road project could result in the belief that recognition would correspond to the optimal strategy. Furthermore, a road project awarded with a "green" rating during the construction phase does not mean that the project results "green" if a life cycle approach is considered. Indeed, the most environmental friendly strategies may not be the ones with the highest performance. Using "greener" materials or performing recycle-related practices may lead to a lower performance over the life cycle and therefore produce an increase in maintenance needed, which could in turn result into more congestion due to work zones and higher total emissions. Therefore, construction and maintenance strategies should be analyzed according to three main parameters: cost, performance or effectiveness, and environmental impacts. The cost analysis part takes into account outflows over the service life of the pavement according to the well-known Life Cycle Cost Analysis methodology. The cheapest maintenance technique over the analysis period was expounded and sensitivity analyses to involved factors were conducted. Performance assessment was developed according to experimental on site data gathered and analyzed over several years to develop deterioration pavement models. Effectiveness of maintenance treatments is further provided and compared to the volume of traffic. In addition, environmental impacts related to maintenance and rehabilitation strategies were analyzed. Emissions were computed over the life cycle of the pavement from the manufacture of raw materials for the initial construction, placement, and maintenance phase. Finally, an optimization procedure was developed for including environmental impacts into a Pavement Management System. A methodology to set a multi-attribute approach system, computing costs, performance, and eco-efficiency over the life cycle of the pavement, is therefore proposed. / Ph. D.

I denna rapport undersöks motorn ZM10 genom att göra en livscykelanalys, även kallad LCA. Analysen görs för att företaget ZPARQ AB ska kunna få en bild av vilken miljöpåverkan deras motor har vid tillverkning. I rapporten är energiåtgång och koldioxidutsläpp det som undersöks. Motorn som är en eldriven OEM-motor med komponenter som tillverkas i framförallt Kina används för marin framfart och är tillverkad för fiskebåtar samt mindre segelbåtar. Det är en motor som till skillnad från sina konkurrenter är just eldriven och i och med det, är den mycket lättare än de fossildrivna konkurrerande båtmotorerna. För att göra livscykelanalysen undersöks en full beställning som företaget ZPARQ AB ämnat att göra. En beställning ser i dagsläget ut att bli på 100 beställda motorer och för att göra analysen används två standarder, ISO 14040 och ISO 14044. Dessa hjälper till att förklara hur man går tillväga för att göra livscykelanalysen men också för hur man levererar resultatet. De fyra huvudkategorierna i en livscykelanalys, mål och omfattning; inventeringsanalys; miljöpåverkan; rapportering, undersöks för att kunna få en helhetsbild av analysen. Genom att göra en strukturerad analys av målet och omfattningen kan man senare gå vidare med inventeringsanalys. Inventeringsanalysen visar på vad det är för olika komponenter, dess material och tillverkningsprocessen av dessa material. Även transporterna för komponenterna från det att de tillverkas till att de hamnar på företagets lager i Älta. Efter att den iterativa processen som är inventeringsanalysen har gjorts, fortsätter man med en miljöpåverkansbedömning, även kallad LCIA. Den visar att tillverkningen av materialet är det som står till grund för den största delen av miljöpåverkan i form av använd energi i (ca 80 300 MJ) samt av koldioxidutsläpp (6 100 kg CO2). Det materialet med mest energi- och koldioxidutsläpp visar sig vara aluminium. Under tillverkningsprocessen står aluminiumet för det största utsläppet i båda kategorierna. Transporten bidrar förhållandevis lite till miljöpåverkan med transporter för de flesta komponenter från Asien till Sverige. Inom standarden ISO 14044 kan man redovisa möjliga förbättringar som kan göras, i detta fall undersöks skillnaden med att använda delvis återvunnet aluminium. Det påvisar minskningar i utsläppen med cirka 18 procent mindre energiåtgång och 17 procent mindre kg CO2 på de 100 motorer som undersöks. Resultatet av analysen är svår att jämföra med annat då den endast sträcker sig från tillverkning av material och komponenter till företagets lagerhållning. I andra analyser undersöker man hela produktens livscykel från “vagga till grav”, denna analys handlar också, till skillnad från andra, om en prototyp. Avslutningsvis rekommenderas det att fortsätta arbetet genom att göra en fullskalig livscykelanalys efter produktens prototypfas är klar, från just vagga till grav för att kunna ge företaget siffror på vad det finns för miljöpåverkan i hela livscykeln. Även att fortsätta arbetet genom att använda programvaror och/eller databaser för att kunna undersöka vad för typer av utsläpp koldioxidutsläppet består av, rekommenderas. / In this report, the ZM10 engine is examined through a life cycle analysis (LCA). This analysis is conducted to provide ZPARQ AB with an understanding of the environmental impact of their engine during manufacturing. The report primarily investigates energy consumption and carbon dioxide emissions. The ZM10, an electric OEM engine manufactured primarily in China, is used for marine propulsion in fishing boats and smaller sailboats. Unlike its fossil-fueled counterparts, this electric engine is significantly lighter. To perform the life cycle analysis, a full order that ZPARQ AB intends to place is examined, currently comprising 100 engines. The analysis adheres to two standards, ISO 14040 and ISO 14044, which guide the methodology of the LCA and the presentation of results. The four main categories of the life cycle analysis—objectives and scope, inventory analysis, environmental impact, and reporting—are explored to provide a comprehensive overview. The analysis begins with a structured examination of the goal and scope, which is followed by an inventory analysis. This analysis details the various components, their materials, and their manufacturing processes. It also includes the transportation of the components from their production sites to the company’s warehouse in Älta. After completing the inventory analysis, the environmental impact assessment (LCIA) is conducted. The LCIA reveals that material manufacturing, particularly of aluminum, constitutes the largest portion of environmental impact, accounting for approximately 80,300 MJ of energy use and 6,100 kg of CO2 emissions. Aluminum manufacturing is the largest contributor to emissions in both categories, while transportation from Asia to Sweden contributes relatively little to the overall environmental impact. Within the framework of ISO 14044, potential improvements are assessed, including the use of partially recycled aluminum. This change could reduce energy consumption and CO2 emissions by approximately 18 percent and 17 percent, respectively, across the 100 engines analyzed. The results of this analysis are challenging to compare with others since it only extends from the manufacture of materials and components to the company’s warehousing. Unlike other analyses that examine the entire life cycle from "cradle to grave," this study focuses on a prototype. In conclusion, it is recommended that ZPARQ AB continue this work by conducting a full-scale life cycle analysis post-prototype phase, covering the entire life cycle "from cradle to grave," to provide comprehensive environmental impact figures. It is also advised to continue utilizing software and/or databases to further investigate the specific types of emissions comprising the CO2 emissions.

In this dissertation we address three different sustainability concepts: [1] modeling of biodiesel production via heterogeneous catalysis, [2] life cycle analysis for pyrolysis of switchgrass for using in power plant, and [3] modeling of pyrolysis of biomass. Thus we deal with Specific Aim 1, 2 and 3. In Specific Aim 1, the models for esterification in biodiesel production via heterogeneous catalysis were developed. The models of the reaction over the catalysts were developed in two parts. First, a kinetic study was performed using a deterministic model to develop a suitable kinetic expression; the related parameters were subsequently estimated by numerical techniques. Second, a stochastic model was developed to further confirm the nature of the reaction at the molecular level. The deterministic and stochastic models were in good agreement. In Specific Aim 2, life cycle analysis and life cycle cost for pyrolysis of switchgrass for using in power plant model were developed. The greenhouse gas (GHG) emission for power generation was investigated through life cycle assessment. The process consists of cultivation, harvesting, transportation, storage, pyrolysis, transportation and power generation. Here pyrolysis oil is converted to electric power through co- combustion in conventional fossil fuel power plants. The conventional power plants which are considered in this work are diesel engine power plant, natural gas turbine power plant, coal-fired steam-cycle power plant and oil-fired steam-cycle power plant. Several scenarios are conducted to determine the effect of selected design variables on the production of pyrolysis oil and type of conventional power plants. In Specific Aim 3, pyrolysis of biomass models were developed. Since modeling of pyrolysis of biomass is complex and challenging because of short reaction times, temperatures as high as a thousand degrees Celsius, and biomass of varying or unknown chemical compositions. As such a deterministic model is not capable of representing the pyrolysis reaction system. We propose a new kinetic reaction model, which would account for significant uncertainty. Specifically we have employed fuzzy modeling using the adaptive neuro-fuzzy inference system (ANFIS) in order to describe the pyrolysis of biomass. The resulting model is in better agreement with experimental data than known deterministic models. / Ph. D.

This study evaluates the carbon footprint of three wastewater treatment plants in Sweden. Two analytical methods are employed with the same input data: an Excel-based model developed by the Swedish Water and Wastewater Association, and a life cycle assessment model using SimaPro software. The findings reveal that emissions range from 0.5 to 0.7 kg CO2 equivalent per cubic meter of purified water, with treatment plant 3 resulting in the highest emissions due to its reliance on non-renewable energy and limited scale. The primary carbon source identified by the climate calculation tool is direct emissions (scope 1), while the life cycle assessment model highlights chemical usage as the major contributor, significantly impacting ecosystem and human health categories. Treatment plant 2 is notably impacted in the life cycle assessment model by high chemical consumption. The study also explores several strategies to mitigate the climate impact of wastewater treatment plants, categorizing them into emission reduction and climate benefit enhancement methods. Scenario analysis indicates that switching to renewable energy sources and reducing direct emissions are the most effective measures. Additionally, utilizing energy and resources from water and sludge can enhance climate benefits. / Med den ökande oron för klimatpåverkan från avloppsreningsverk har forskare börjat försöka bygga modeller för koldioxidavtryck på anläggningsskala. Den nordiska vattenföreningen har i samarbete med Danmark, Sverige, Norge och Finland utvecklat modeller för att uppskatta koldioxidavtrycket i avloppsreningsverk i de nordiska länderna. Denna studie utvärderar koldioxidavtrycket från tre avloppsreningsverk i Sverige. Analysen använder två olika metoder: en Excel-baserad modell utvecklad av Svenskt Vatten och en livscykelanalys modell med programvaran SimaPro. Båda modellerna använder samma indata men genomför oberoende analyser.  Resultaten visar att utsläppen varierar från 0,5 till 0,7 kg CO2-ekvivalenter per kubikmeter renat vatten, där en anläggning uppvisar de högsta utsläppen på grund av sitt beroende av icke-förnybar energi och begränsade skala. Den primära källan till koldioxidutsläpp som identifieras av klimatberäkningsverktyget är direkta utsläpp, medan LCA-modellen betonar kemikalieanvändning som den största bidragsgivaren, vilket signifikant påverkar ekosystem och människors hälsa. En annan reningsverk påverkas särskilt av hög kemikaliekonsumtion.  Studien utforskar flera strategier för att minska klimatpåverkan från reningsverk och kategoriserar dem i utsläppsreduktion och metoder för att öka klimatfördelarna. Scenarieanalys indikerar att byta till förnybara energikällor och minska direkta utsläpp är de mest effektiva åtgärderna. Dessutom kan användning av energi och resurser från vatten och slam öka klimatfördelarna.  Klimatberäkningsverktyget är specialiserat och lokaliserat för avloppsreningsverk, medan livscykelanalysmodellen erbjuder bredare användbarhet över olika industrier och globala sammanhang, även om den är mindre specifik. Den förra fokuserar enbart på koldioxidavtryck i CO2-ekvivalenter, medan den senare omfattar ett bredare spektrum av miljöpåverkan. Framtida tillämpningar kan dra nytta av att integrera båda modellerna för att uppnå mer exakta och omfattande resultat.