scholarly journals Antifreeze life cycle assessment, II: Mathematical modeling

2005 ◽  
Vol 11 (2) ◽  
pp. 85-92
Author(s):  
Jelena Kesic ◽  
Dejan Skala
Keyword(s):  
Mathematical Modeling ◽  
Life Cycle Assessment ◽  
Life Cycle ◽  
Satisfactory Solution ◽  
Different Types ◽  
Two Parameters ◽  
Energy Processes ◽  
Energy Balances ◽  
Mass And Energy Balances

A mathematical model based on the mass and energy balances of all the processes included in antifreeze life cycle assessment (LCA) was defined in the first part of this study [1]. The part of energy that can be transformed into some other kind of energy is called exergy in all energy processes. The concept of exergy considers the quality of different types of energy and materials. It is also a connection between energy and mass transformations where the physical meaning of exergy loss is the loss of material and energy that must be used in the process. The results of the LCA calculation are very useful for analyzing the obtained products and used processes and for determining the conditions under which this analysis was conducted. The result of this study indicated that recycling is the most satisfactory solution for the treatment of used antifreeze taking into account two parameters: material and energy consumption. The reuse of antifreeze should not be neglected as a solution of this analysis.

scholarly journals Antifreeze life cycle assessment (LCA)

2005 ◽  
Vol 59 (5-6) ◽  
pp. 132-140 ◽  
Author(s):  
Jelena Kesic ◽  
Dejan Skala
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Ethylene Glycol ◽  
Raw Materials ◽  
Energy Inputs ◽  
Energy Processes ◽  
Energy Balances ◽  
Whole Life Cycle

Antifreeze based on ethylene glycol is a commonly used commercial product The classification of ethylene glycol as a toxic material increased the disposal costs for used antifreeze and life cycle assessment became a necessity. Life Cycle Assessment (LCA) considers the identification and quantification of raw materials and energy inputs and waste outputs during the whole life cycle of the analyzed product. The objectives of LCA are the evaluation of impacts on the environment and improvements of processes in order to reduce and/or eliminate waste. LCA is conducted through a mathematical model derived from mass and energy balances of all the processes included in the life cycle. In all energy processes the part of energy that can be transformed into some other kind of energy is called exergy. The concept of exergy considers the quality of different types of energy and the quality of different materials. It is also a connection between energy and mass transformations. The whole life cycle can be described by the value of the total loss of exergy. The physical meaning of this value is the loss of material and energy that can be used. The results of LCA are very useful for the analyzed products and processes and for the determined conditions under which the analysis was conducted. The results of this study indicate that recycling is the most satisfactory solution for the treatment of used antifreeze regarding material and energy consumption but the re-use of antifreeze should not be neglected as a solution.

scholarly journals Engineering Design Process of Face Masks Based on Circularity and Life Cycle Assessment in the Constraint of the COVID-19 Pandemic

2021 ◽  
Vol 13 (9) ◽  
pp. 4948
Author(s):  
Núria Boix Rodríguez ◽  
Giovanni Formentini ◽  
Claudio Favi ◽  
Marco Marconi
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Environmental Sustainability ◽  
Design Guidelines ◽  
New Device ◽  
Engineering Design Process ◽  
Life Cycle Perspective ◽  
Different Types ◽  
3D Printed ◽  
Negative Impacts

Face masks are currently considered key equipment to protect people against the COVID-19 pandemic. The demand for such devices is considerable, as is the amount of plastic waste generated after their use (approximately 1.6 million tons/day since the outbreak). Even if the sanitary emergency must have the maximum priority, environmental concerns require investigation to find possible mitigation solutions. The aim of this work is to develop an eco-design actions guide that supports the design of dedicated masks, in a manner to reduce the negative impacts of these devices on the environment during the pandemic period. Toward this aim, an environmental assessment based on life cycle assessment and circularity assessment (material circularity indicator) of different types of masks have been carried out on (i) a 3D-printed mask with changeable filters, (ii) a surgical mask, (iii) an FFP2 mask with valve, (iv) an FFP2 mask without valve, and (v) a washable mask. Results highlight how reusable masks (i.e., 3D-printed masks and washable masks) are the most sustainable from a life cycle perspective, drastically reducing the environmental impacts in all categories. The outcomes of the analysis provide a framework to derive a set of eco-design guidelines which have been used to design a new device that couples protection requirements against the virus and environmental sustainability.

Data Reconciliation Applied in a Transfer and Storage Terminal

2006 ◽  
Author(s):  
Rafael Noac Feldman ◽  
Elcio Cruz de Oliveira
Keyword(s):  
Diesel Oil ◽  
Data Reconciliation ◽  
Systematic Bias ◽  
Random Errors ◽  
Single Measure ◽  
Gross Error ◽  
Energy Balances ◽  
And Storage ◽  
Mass And Energy Balances

In a simply manner, data reconciliation is a mathematic treatment with propose of a better quality of the data in a process. Industrial processes typically have a large number of measured variables, which presents some degree of random errors and, less frequently, gross errors. In this text, in order to simplify the notation and terminology we classify all instrument and process errors in these two categories. Any significant systematic bias is included in the gross error category. Data reconciliation allows the measurements to be adjusted (“reconciled”) to satisfy process restrictions (mass and energy balances) and improve measurements quality. The results obtained by data reconciliation can also provide benefits in custody transfer issues. Custody transfer is the responsibility transfer during the storage and transportation of a measured refined product volume. Any loss or gain resulting in a non-trustful measurement is considered as the transportation company responsibility. Therefore, the work objective is to propose a data reconciliation methodology, in a process involving diesel oil custody transfer in a Transpetro’s terminal (Terminal of Sao Caetano do Sul), in order to evaluate and correct possible inconsistencies, besides to know a single measure that represents better the measurement system. In this study we will use data from static measurement in tanks, dynamic measurement in turbine and ultra-sonic device. A database will be obtained in two basic steps: process modeling and data reconciliation to consolidate the mass balance. The reconciled value shows us that there is a bias in the ultra-sonic meter and the turbine meter measurement is more reliable, as expected.

scholarly journals Functional Unit for Impact Assessment in the Mining Sector—Part 1

2020 ◽  
Vol 12 (22) ◽  
pp. 9313
Author(s):  
Julien Bongono ◽  
Birol Elevli ◽  
Bertrand Laratte
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Functional Unit ◽  
Multiscale Approach ◽  
Mining Sector ◽  
End Use ◽  
Definition Of ◽  
Sector Part ◽  
Selection Of

More and more efforts are directed towards the standardization of the methods of determining the functional unit (FU) in a Life Cycle Assessment (LCA). These efforts concern the development of theories and detailed methodological guides, but also the evaluation of the quality of the FU obtained. The objective of this article is to review this work in order to propose, using a multiscale approach, a method for defining the FU in the mining sector, which takes into account all the dimensions of the system under study. In this first part, the emphasis is on identifying the shortcomings of the FU. The absence of a precise normative framework specific to each sector of activity, as well as the complex, multifunctional and hard-to-scale nature of the systems concerned, are at the origin of the flexibility in the selection of the FU. This lack of a framework, beyond generating a heterogeneous definition of the FU for the same system, most often leads to an incomplete formulation of this sensitive concept of LCA. It has been found that key parameters such as the end-use of a product or process, as well as the interests of stakeholders, are hardly taken into account in the specification of the FU.

scholarly journals Life Cycle Assessment and Quality of Utilization of Paint Waste as a Raw Material of Paving Block

2020 ◽  
Vol 21 (2) ◽  
pp. 89-94
Author(s):  
Purwanto Purwanto ◽  
Ari Dina Citra ◽  
Henna Soenoko
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Raw Material

scholarly journals Mathematical modelling of steam-water cycle with auxiliary empirical functions application

2010 ◽  
Vol 31 (3) ◽  
pp. 165-183 ◽  
Author(s):  
Grzegorz Szapajko ◽  
Henryk Rusinowski
Keyword(s):  
Heat Transfer ◽  
Mathematical Modelling ◽  
Water Cycle ◽  
Empirical Modelling ◽  
Flow Capacity ◽  
Energy Processes ◽  
Semiempirical Models ◽  
Energy Balances ◽  
Modelling Methods ◽  
Mass And Energy Balances

Mathematical modelling of steam-water cycle with auxiliary empirical functions applicationResearch oriented on identification of operating states variations with the application of mathematical models of thermal processes has been developed in the field of energy processes diagnostics. Simple models, characterised by short calculation time, are necessary for thermal diagnostics needs. Such models can be obtained using empirical modelling methods. Good results brings the construction of analytical model with auxiliary empirical built-in functions. The paper presents a mathematical model of a steam-water cycle containing mass and energy balances and semiempirical models of steam expansion line in turbine as well as heat transfer in exchangers. A model of steam expansion line in a turbine is worked out with the application of a steam flow capacity equation and an internal efficiency of process equation for each group of stages for the analysed turbine. A model of a heat exchanger contains energy balance and the relation describing heat transfer in an exchanger, proposed by Beckman. Estimation of empirical equations coefficients was realised with the application of special and reliable measurements. Estimation criterion was a weighted relative sum of the remainder squares. There are exemplary calculations results presented in the final part of paper.

Comparing environmental impacts of additive manufacturing vs traditional machining via life-cycle assessment

2015 ◽  
Vol 21 (1) ◽  
pp. 14-33 ◽  
Author(s):  
Jeremy Faludi ◽  
Cindy Bayley ◽  
Suraj Bhogal ◽  
Myles Iribarne
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Additive Manufacturing ◽  
Environmental Impacts ◽  
Surface Finish ◽  
Numerical Control ◽  
Cutting Fluid ◽  
Content Type ◽  
Electricity Use

Purpose – The purpose of this study is to compare the environmental impacts of two additive manufacturing machines to a traditional computer numerical control (CNC) milling machine to determine which method is the most sustainable. Design/methodology/approach – A life-cycle assessment (LCA) was performed, comparing a Haas VF0 CNC mill to two methods of additive manufacturing: a Dimension 1200BST FDM and an Objet Connex 350 “inkjet”/“polyjet”. The LCA’s functional unit was the manufacturing of two specific parts in acrylonitrile butadiene styrene (ABS) plastic or similar polymer, as required by the machines. The scope was cradle to grave, including embodied impacts, transportation, energy used during manufacturing, energy used while idling and in standby, material used in final parts, waste material generated, cutting fluid for CNC, and disposal. Several scenarios were considered, all scored using the ReCiPe Endpoint H and IMPACT 2002+ methodologies. Findings – Results showed that the sustainability of additive manufacturing vs CNC machining depends primarily on the per cent utilization of each machine. Higher utilization both reduces idling energy use and amortizes the embodied impacts of each machine. For both three-dimensional (3D) printers, electricity use is always the dominant impact, but for CNC at maximum utilization, material waste became dominant, and cutting fluid was roughly on par with electricity use. At both high and low utilization, the fused deposition modeling (FDM) machine had the lowest ecological impacts per part. The inkjet machine sometimes performed better and sometimes worse than CNC, depending on idle time/energy and on process parameters. Research limitations/implications – The study only compared additive manufacturing in plastic, and did not include other additive manufacturing technologies, such as selective laser sintering or stereolithography. It also does not include post-processing that might bring the surface finish of FDM parts up to the quality of inkjet or CNC parts. Practical implications – Designers and engineers seeking to minimize the environmental impacts of their prototypes should share high-utilization machines, and are advised to use FDM machines over CNC mills or polyjet machines if they provide sufficient quality of surface finish. Originality/value – This is the first paper quantitatively comparing the environmental impacts of additive manufacturing with traditional machining. It also provides a more comprehensive measurement of environmental impacts than most studies of either milling or additive manufacturing alone – it includes not merely CO2 emissions or waste but also acidification, eutrophication, human toxicity, ecotoxicity and other impact categories. Designers, engineers and job shop managers may use the results to guide sourcing or purchasing decisions related to rapid prototyping.

scholarly journals Life cycle assessment analysis of kenaf cultivation in bonorowo land, laren, lamongan

2019 ◽  
Vol 3 (2) ◽  
pp. 89
Author(s):  
Desrina Yusi Irawati ◽  
Lusi Mei Cahya Wulandari
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Negative Impact ◽  
Organic Fertilizer ◽  
Impact Category ◽  
Impact Measurement ◽  
Urea Fertilizer ◽  
Significant Negative Impact ◽  
Resource Group

The largest kenaf culture in Indonesia is in Laren, Lamongan. Kenaf plants are suitable to be planted in the Bonorowo field. The less potential land conditions make the cultivation of kenaf plants must use chemicals. The use of chemicals has the potential to harm the environment. The approach to identifying and analyzing environmental impacts is the Life Cycle Assessment (LCA). LCA is one method to find out the life cycle of agriculture. LCA stages are Goal and Scope Definition, Life Cycle Inventory, Life Cycle Impact Assessment, and Interpretation. Environmental impact measurement is based on fifteen categories grouped into four categories. LCA processing results show the use of urea fertilizer has the most significant negative impact on the environment. The biggest impact category due to the use of urea fertilizer is aquatic ecotoxicity. The use of urea fertilizer affects the types of resources, climate change, ecosystem quality, and human health. Of the four groups, which have the highest value, are the resource group. The use of urea fertilizer has the most significant role in the success of kenaf cultivation because kenaf cultivation requires more N elements to improve the quality of kenaf stems. The use of organic fertilizer can be an option to reduce the use of urea fertilizer.

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