Sustainabledevelopment is an emerging concept that enhance quality of life and thusallowing people to live in a healthy environment and improve social, economicand environmental conditions for present and future generations. Therefore, theimproving social, economic and environmental indicators of sustainabledevelopment are drawing attention to the construction industry, which is aglobally emerging sector, and a highly active industry in both developed anddeveloping countries (Ullah, Perret et al. 2016).Theiron and steel industry (ISI) is the world’s biggest energy consuming manufacturingindustry with the largest share in the world’s economy. In the iron and steelproduction over world, China takes the first place, and Japan, U.S.
follow it.Iron and steel production is highly energy intensive and therefore it isassociated highly with resource conservation, energy efficiency, and emissionsreduction. In order to overcome the increasing concern of today’s resourcedepletion and to address environmental considerations in both developed anddeveloping countries, life cycle assessment (LCA) can be applied to decisionmaking in order to improve sustainability in the construction industry (Bribián, Capilla et al. 2011, Renzulli, Notarnicolaet al. 2016).TheWorld Steel Association provides the most consistent and accurate informationfor LCAs of the steel industry. It collects life cycle inventory data on thesteel life cycle, including raw material extraction, manufacturing, use phase and end-of-life processes.
The researchers focusingon the world steel industry have stressed the importance of LCA inenvironmental assessment (Burchart-Korol 2013, Ullah, Perret et al. 2016).LCAis a widely used methodology to assess environmental performances of productsand processes taking into account the whole life cycleof the products (ISO 14040, 2006; ISO 16 14044, 2006).
It helps to identify the environmental impactshotspots and corresponding decisions can be defined (Vázquez-Rowe, Villanueva-Rey et al. 2012). There arelimitations to use LCA as a stand-alone methodological approach tosustainability analysis (Vázquez-Rowe, Villanueva-Rey et al. 2012). To that aimeconomic-ecological efficiency or commonly known as eco-efficiency is a usefuloperational concept.
The concept of eco-efficiency refers to a process increaseoutput value, and lesser negative impacts (World Business Council for Sustainable Development, 2000). Eco-efficiency was defined by OECD, (1998) as the ratio of economic value per environmental impacts. Indicators related to eco-efficiency can be assessed through a product’s economic value against its environmental impact (Van Passel, Van Huylenbroeck et al. 2009).Eco-efficiency can help policy- makers to formulate, implement and assess measures to improve the economic activity with reduced amount ofnegative impacts on environment. (Van Passel, Van Huylenbroeck et al. 2009) stated thateco-efficiency is a useful operational metric to assess farm levelsustainability. It may be used as aproxy to sustainability indicator (OECD, 1998).
(Picazo-Tadeo, Beltrán-Esteve et al. 2012)argued that anygiven production process leads to a set of environmental impact indicators (e.g.through the use of life cycle assessment -LCA), hence to a set of eco-efficiencyratios (Young 1996, Burchart-Korol 2013). 2. Objectives Objectivesof this study are:· To evaluate the life-cycle approach forassessment of environmental impacts associated with industrial material (Steel) and product systems;· To consider broad-based possibilitiesfor environmental improvements arising from · materials selection and product design;· To determine specific environmentalimpacts associated with the production/use/EOL of industrial materials and,· To evaluate and compare eco-efficiencyof steel products between China and Pakistan.3. Materials andmethodsToexplore the objectives outlined above, a survey along with a field experimentwill be conducted.
3.1. Life-cycle assessmentLCAcalculations were accomplished by using software SimaPro version 7.2.4 incompliance with ISO 14040 (2006) that defines four main steps within an LCAstudy: goal and scope definition, inventory modeling, impact assessment, andfinal interpretation. (Ortiz, Castells et al.
2009)3.1.1. Goal and scopedefinitionThegoal of the study was to assess the environmental impacts of steel industriesin Pakistan and China and to compare the impacts associated with thesub-processes as well as the impacts associated with the final products. Thesystem boundary was assigned as “cradle to gate”. Upstream processes,transportation, production processes and utility services were included tocradle to gate boundary. The upstream processes are acquisitions of rawmaterials, energy and auxiliary materials.
The transportation stage indicatesthe transportation of materials such as raw materials, auxiliary materials andfuels. The production processes for steel production are divided into two; themain production system and the utility services. The main production systemcomprises of the following sub-processes; coke making(CM), sintering (S), blastfurnaces (BF), basic oxygen furnaces (BOF),casting (C) and hot rolling (HR).The utility services include energy and water facilities and mechanicalworkshop.
Energy facility comprises boiler, turbo generator, turbo blower, purewater, waste heat, and oxygen plants producing steam, electricity, compressedair, steam and oxygen respectively. Water facility supplies pure water, servicewater and sea water. Mechanical workshop is responsible for repair andmanufacturing of machine parts. The mechanical workshop had been excludedduring the LCA evaluations conducted for the sub-processes and products as thecontribution of this unit to specific processes or products cannot be disintegrated(Olmez, Dilek et al. 2016).3.1.
2. Data inventoryThedata inventory stage involves the quantification of flows and materials andenergy required to produce the functional unit of interest. In the presentstudy, a field study was carried out in one of the three integrated iron andsteel production facilities in China/Pakistan in order to collect the inventorydata. Thus, this facility is considered as a representative sample of integratedsteel industry in terms of manufacturing technologies and production capacity.
The information about acquisitions of raw materials, energy and auxiliarymaterials were not obtained from the facility, but, instead was taken from theinventories in the database of SimaPro. Among the databases involved, primarilyEco invent database was preferred (Olmez, Dilek et al. 2016).
3.2 Life cycle impactassessment methodsTheimpact assessment steps were Characterization, Damage Assessment, Normalizationand Single Score. A method covering the category indicators at endpoint levelwas favored in this study. By this way, the results of midpoint level can alsobe seen and to ease the interpretation step endpoint results were used (Young 1996, Olmez, Dilek et al. 2016).3.3 InterpretationThelast phase of the LCA process is life cycle interpretation. The objectives ofthis step is to analyze results and reach conclusions based on the findings ofthe preceding 3 phases (ISO, 2006).
(Olmez, Dilek et al. 2016).3.4 Process-based LCAProcess-basedenvironmental impacts were assessed in order to detect the most pollutingsub-processes during liquid steel production.
The assessment was performed forthe selected product of the corresponding sub-process and to determine thecontributions of each sub-process to various environmental impact categories (Olmez, Dilek et al. 2016).4. Expected OutcomesThisresearch presents the results of an LCA study comparing the most commonly usedbuilding materials i.
e. steel with some eco-materials using different impactcategories. The aim is to deepen the knowledge of energy and environmentalspecifications of building materials, analyzing their possibilities for improvementand providing guidelines for materials selection in the eco-design of newbuildings and rehabilitation of existing buildings and comparing the steelmaterial in both countries (Burchart-Korol 2013).5. Significanceof the researchSteel production, and the iron-making process in particular, is a very energy-intensive industry. Theapplication of environmental life cycle assessment (LCA) allows steel producers to improve the manufacturingprocess by reducing environmental impacts. It was found that the most significant environmental impact was damage to human health, which was related to coke consumptionin the blast furnace and iron ore consumption in the sinter plant.
The largest energy demand inthe entire steel production system occurred in the blast furnace system production, and the major source of environmental impacts was the consumption of fossil fuels. Direct GHG emissions wererelated to the emissions of combustion sources. Significant sources of GHGemissions included coke, coke breeze, coke oven gas and electricity, and the biggest source of metal and mineral depletion was iron consumption in the sintering process