Landfill Reduction Research Articles

Potentials for a circular economy of mineral construction materials and demolition waste in urban areas: a case study from Vienna

Mineral construction and demolition wastes (CDW) are generated when buildings and infrastructures are renovated and when they reach their end of life. As one of the largest waste streams, they have a considerable potential for the reduction of waste generation, landfilling, and primary raw material consumption. To make use of this potential, sustainable development strategies of many cities include a circular management of CDW by measures in line with the waste hierarchy. The present study uses material flow analysis to determine how waste reduction, re-use and recycling of mineral CDW generated in a city can contribute to reduce the demand of raw material imports for construction minerals, using the case study of the city of Vienna. The results show that the annual consumption of construction minerals of 4.5 million tons can be reduced by 32% to 3 million tons by implementing the waste hierarchy to CDW. The most important measures are the use of recycling materials from mineral construction and demolition waste as recycling aggregate in concrete (575,000 t/yr), followed by the use of recycling material to substitute gravel in unbound form (463,000 t/yr), avoiding the demolition of historical buildings by extending their service life (230,000 t/yr), asphalt recycling (85,000 t/yr), and substitution of raw-mix in cement by recycling material from debris (84,000 t/yr). Re-use of full bricks (17,000 t/yr) is of lesser relevance. To implement this enhanced circularity scenario, however, efforts in installed technology, construction and demolition waste management as well as legal and entrepreneurial measures are required.

The influence of microbial community dynamics on anaerobic digestion efficiency and stability: A Review

An essential component in sustainable energy development is the production of bioenergy from waste. The most successful bioenergy technology worldwide is anaerobic digestion (AD), which is a microbially-mediated process of organic feedstock conversion into energy-rich compounds (volatile fatty acids (VFA) and biogas) for renewable energy generation. AD is deployed in a range of situations including systems for on-farm energy recovery from animal and plant waste to the processing of food and municipal solid waste (with the additional benefit of land-fill reduction).Anaerobic digesters rely on a diverse microbial community working syntrophycally through a series of interrelated biochemical processes.Each stage in anaerobic digestion is carried out by different microbial groups. Thus, to optimise energy recovery from the AD process, the microbial community must have stable performance over time, balancing the various metabolic functions and taxonomic community composition in digesters. Complicating this balance, it has been found that the presence of ammonia, sulphate, and hydrogen sulphide in substantial concentrations often cause failure in the AD process. Thus, these substances cause adverse shifts in microbial community composition and/or inhibit bacterial growth, that influencing AD performance. ©2020. CBIORE-IJRED. All rights reserved

Waste-to-Landfill Reduction: Assessment of Cost-Effective Solutions using an Optimisation Model

Significant increases in solid waste generation and inappropriate waste management system leads to overloaded landfills, which have negative impacts on the environment and human health. Reducing waste sent to landfill has become an emerging mission in Vietnam. This study aims at assessing cost-effective solutions to reduce waste-to-landfill amount using system analysis approach. A single-objective optimisation model is formulated to minimise the cost of the system in association with different landfill waste reduction targets and values of waste separation efficiency for Hoi An city. As a result, the landfill target is directly proportional to the cost. It means the higher landfill reduction target leads to the higher cost of the system. Meanwhile, the separation efficiency is inversely proportional to the system cost. The result showed that twenty-five percent of municipal waste treated in landfills is achievable target based on the current condition of the city. Also, ten percent of municipal waste sent to landfill is an infeasible mission if the waste separation rate is too low. If waste is wholly separated at source, incineration, composting and landfill can be applied as main treatment alternatives to reduce seventy-five percent of municipal waste sent to landfill with the cost of about 1,800 USD/d.

Investigation of tensile strength and elongation properties of chenille upholstery fabrics including recycling polyester yarns

Every day, millions of plastic and polyethylene terephthalate bottles are being thrown away by people. This leads not only to the reduction of landfills and increase in environmental problems but also to pollution of marine and oceans that affect the lives of many living things. Therefore, recycling of waste polyethylene terephthalate bottles with recycling technologies has great environmental importance. In this study, recycled polyester yarns obtained by recycling waste polyethylene terephthalate bottles and standard polyester yarns were used in staple forms, as well as binder and pile yarns of the chenille yarn structure. In this context, 16 different chenille yarns were produced and the production parameters such as rotor speed, spindle speed, and pile density are kept constant by selecting the appropriate values. Then, these chenille yarns were used as weft to produce upholstery fabrics. Tensile strength and elongation tests were applied to the upholstery fabrics, and the results were evaluated statistically. As a result of the tensile strength tests and statistical analyses, it is concluded that the weft breaking strength of all types of woven fabrics, which have 100% recycled polyester in the structures of chenille yarns as weft, is slightly decreased compared to other types, but this decrease is not statistically significant. The use of recycled polyester yarns in the structures of chenille yarns, which are widely used in the upholstery sector, will be beneficial in producing more sustainable and eco-friendly fabrics.

Assessing the economic and environmental sustainability of household food waste management in the UK: Current situation and future scenarios

The value embedded in food waste is increasingly being recognised, with the UN targeting a 50% reduction in consumer food waste and the EU recycling of 60% of all household waste, both by 2030. Aiming to provide guidance on the most sustainable food waste utilisation routes, this study evaluates the life cycle environmental and economic sustainability of five plausible scenarios for the year 2030. Focusing on the UK for context, these are compared to the current treatment of food waste as well as to its potential future prevention. The scenarios consider a differing share of four widely-used treatment methods: anaerobic digestion, in-vessel composting, incineration and landfilling. The scenario with the highest anaerobic digestion share that recovers both heat and electricity is the best option for seven out of 19 environmental impacts and the second best for life cycle costs. Upgrading anaerobic digestion biogas to biomethane achieves the lowest global warming potential and life cycle costs. Net-negative global warming potential (savings) can be achieved if the heat from anaerobic digestion and incineration or biomethane are utilised to displace natural gas. Displacing a future electricity mix does not lead to significant global warming potential savings due to the expected grid decarbonisation. However, savings are still achieved for metal depletion and human and terrestrial toxicities as they are higher for decarbonised grid electricity due to the increased share of renewables. A greater share of in-vessel composting leads to higher impacts because of the high electricity consumption. Landfill reduction has an economic advantage for all the scenarios, except for the business-as-usual, with life cycle costs 11–75% lower than for the current situation. While future scenarios improve the overall sustainability compared to the current situation, halving food waste by 2030 can save 15 times more greenhouse gas emissions than the best treatment scenario without waste reduction. Therefore, any commitments to improve the sustainability of food waste treatment must be accompanied by an effective waste prevention strategy. The outcomes of this work can help waste treatment operators and policy makers towards more sustainable food waste management. Although the focus is on UK situation, the overall conclusions and recommendations are applicable to other regions.

Regression models to predict workability and strength of flowable concrete containing recycled aggregates

Regression models are rigorous computational techniques for developing and optimizing performance of cementitious-based concrete materials used for civil and infrastructure engineering works. This paper is part of a comprehensive research program undertaken to develop regression models that predict the behavior of self-consolidating concrete (SCC) containing recycled aggregates, for given proportioning constraints while minimizing the number of trials. Two series of SCC mixtures prepared with 375 and 450 kg/m3 cement are tested. The water-to-cement ratios varied from 0.5 to 0.38, while the natural coarse aggregates were partially substituted by recycled ones at different rates varying from 0% to 100%. Tested properties include the rheology, passing ability, segregation, bleeding, surface settlement, and 28-days compressive strength. Reported regression models can be of particular interest to concrete researchers and engineering seeking for higher recycling technologies and improved sustainability in construction through conservation of virgin aggregate resources, energy savings, landfill reduction, and reduced CO2 emissions.

Optimization of operations for nitrous oxide production and mitigation in aerobic and Aerobic-Anaerobic landfill method on MSW degradation

N2O is a potent greenhouse gas, induced by aeration coupled with leachate recirculation in Municipal Solid Waste (MSW) landfills. In this study, N2O emission was measured in the aerobic and Aerobic-Anaerobic Landfill Method (AALM) with or without leachate recirculation at two aeration rates in synthetic MSW. The experiment was carried out for six Plexiglass® landfill simulation reactors. Low aeration (1.6 l/kg-DM/h) was supplied in RLA, RLAA (Recirculatory) and LAA (non-recirculatory) reactors, while an aeration rate three times higher (4.8 l/kg-DM/h) was performed for RHA, RHAA, and HAA reactors. Based on the supplied leachate quantity, leachate recirculation was performed in five different phases. The results showed that a significant amount of N2O was produced in all reactors. The largest N2O emission of 0.11 and 0.13 g/kg-DM were observed in the RHA and RHAA reactors, respectively. Higher N2O and cumulative GHG was produced in high aeration reactors compared to the low aeration reactors. Recirculated leachate promoted waste stabilization, as reflected in the diminishing CH4 production and other leachate pollutant parameters, especially NH4+-N. It has been evaluated that in the operative or newly placed waste landfill, in-situ aeration with leachate recirculation exhibits the significant N2O production. However, lower amount of leachate in the later stage beneficial to inhibit the N2O production. It is recommended that in-situ aeration will become more effective after the recovery of CH4 from newly placed waste in an operative landfill for net GHG reduction, especially N2O reduction and early stabilization of landfills.

The Cycle rate as the means for real-time monitoring of wastes in circular economy

The EC circular economy waste directive sets ambitious recycling and reuse targets towards waste reduction and banning of landfills. Monitoring of wastes can lead to efficient policies and implementation of proactive measures for waste reduction. Up-to-date methods for waste monitoring in cyclic economy (CE) may not provide reliable and useful figures. Product stock-in-use and flows in CE, including waste flows, are uncertain due to varying demand and imports/exports, random, early losses of stock-in-use, delayed and distributed product returns or end-of-life exit and varying utilization of returns by remanufacturers. Adopting a systems perspective and using a dynamic/stochastic model of stock and flows in CE, this work quantifies waste monitoring and reduction under realistic conditions. It reveals how consumption and stock depletion consist the driving forces of waste generation, compensated by cyclic actions, reuse/remanufacturing and recycle. The conventional recycling rate and other key parameters, including the reuse rate, the mean lifetime, the remanufacturing rate, the number of reuse cycles, are shown inapt to accurately monitor end-wastes. None can consistently distinguish the environmentally superior system or state, featuring lower end-wastes. Higher recycling rates and/or higher reuse rates may not ensure lower wastes. Asymmetric policies (differing recycle and reuse rates) can be advantageous: higher reuse is preferable under rising stock and higher recycle under stock depletion. Sharp real-time monitoring of end-wastes is provided by the cycle rate, a dimensionless rate accounting for consumption and stock variations in CE. Its supreme efficacy is demonstrated in a robust Case study (US cellular phones) via Markov-Chain-Monte-Carlo simulation.

Designing the incineration process for improving the cementitious performance of sewage sludge ash in Portland and blended cement systems

Currently, there is little doubt that the global temperature increase is a consequence of the concentrations of manmade greenhouse gases. Sustainable alternatives such as the use of supplementary cementitious materials and the reduction of sanitary landfills through the incineration of sewage sludge hold promise for the reduction of these gases.An experimental design is proposed to make the incineration of sewage sludge (SS) more efficient, thereby improving the sewage slush ash (SSA) produced as a supplementary cementitious material. Different maximum temperatures and residence times were studied in the partial replacement of Portland and blended cements; the resulting SSAs contributed to the mechanical behavior of concrete through improved hydraulic and pozzolanic activity in addition to intense interactions with cement.The particle size distributions of the SSAs were similar to those of the cements, but the specific surface areas of the SSAs were up to 18 times higher than those of the cements. This vast difference is explained by the presence of micropores after the incineration process. Consequently, the specific surface area of the SSA particles was the most important property explaining the pozzolanic activity and interaction effects with cement. Lower incineration temperatures and higher incineration times increased the specific surface area, therefore increasing the cementitious performance of SSA. The SSA cementitious performance was lower in blended cement than in Portland cement; however, the replacement of blended cement by SSA increased the compressive strength at early and late ages.

Prediction studies of environment-friendly biodegradable polymeric packaging based on PLA. Influence of specimens’ thickness on the hydrolytic degradation profile

Application of new biodegradable polymer packaging based on polylactide (PLA), susceptible to organic recycling, can help in the waste reduction in landfills. In this paper, the results of the study on abiotic degradation of PLA and its blend containing 15 mol% of poly[(R,S)-3-hydroxybutyrate], as a model for the first step of organic recycling were presented. The samples used for this study have different shapes and thicknesses: rigid films and cuboid-bars. Particular emphasis was placed on determining the pattern of degradation products released into the medium. Originally, the results of present study revealed that the application of electrospray ionization mass spectrometry supported by high performance liquid chromatography allowed envisaging the differences in the degradation products pattern released from the studied PLA-based samples differing in thickness. The significant differences in degradation products pattern were predominately observed in the first steps of incubation process and are caused by an autocatalytic effect, which occurs mainly during degradation of the large size PLA samples. Although, the thickness of PLA-based packaging changes the degradation product patterns, however this does not increase the total amounts of acids released to the medium. Thus, it may be concluded that thickness should not affect significantly organic recycling of the packaging.

Steps towards more environmentally sustainable municipal solid waste management – A life cycle assessment study of São Paulo, Brazil

Abstract Landfill disposal has thus far been the predominant treatment method for municipal solid waste (MSW) throughout Brazil, including Sao Paulo city. Environmentally sustainable development of MSW management in Sao Paulo necessitates a stepwise reduction of landfilling. However, ever increasing MSW generation poses the challenge of managing increasing MSW volumes while simultaneously modernizing the MSW management system. In this study, the environmental impacts of the current MSW management system and future alternatives in the city were assessed by means of life cycle assessment (LCA) to determine a pathway towards more environmentally sustainable MSW management. The assessed impact categories were global warming, acidification and eutrophication potentials. Potential future alternatives included the stepwise reduction of landfilling by the introduction of composting, anaerobic digestion and mechanical-biological treatment (MBT). The results of the study indicated that the environmental impacts of MSW management in Sao Paulo can be most effectively diminished by anaerobic digestion of source separated organic waste and MBT of MSW, on condition that the produced refuse-derived fuel (RDF) is utilized in cement production as a substitute for coal. The other utilization option for RDF, incineration, would increase the environmental impacts of MSW management due to the low amount of avoided emissions resulting from electricity substitution since average electricity production in Brazil is dominated by hydropower. Sensitivity analyses indicated, however, that the environmental impacts of incineration might decrease with different modeling assumptions, e.g. the modeling assumption regarding the kind of electricity production substituted by electricity production from MSW. Nevertheless, the main findings of the study remained the same and they are in line with the previous literature.

Thermal performance enhancement of eco-friendly bricks incorporating agro-wastes

Thermal conductivity of bricks is an important parameter as it directly influences the heat losses from buildings and thus increases the energy consumption. The main focus of this study was to develop thermally efficient burnt clay bricks incorporating agricultural wastes on industrial scale. For this purpose, agricultural wastes (sugarcane bagasse ash (SBA) and rice husk ash (RHA)) were acquired from a sugar industry and a brick kiln. Burnt clay bricks were manufactured in an industrial kiln by incorporating SBA and RHA in various dosages (i.e. 5%, 10% and 15%) by clay weight. Physico-mechanical and thermal properties of brick specimens incorporating agricultural wastes were studied. It was observed that lighter weight bricks can be produced using agricultural wastes, which are helpful in reducing both the cost and overall weight of the structure. Addition of agricultural wastes in burnt clay bricks resulted into reduced compressive strength. However, brick specimens incorporating SBA and RHA up to 15% satisfied the minimum requirement for compressive strength according to different standards for masonry construction. Increase in apparent porosity with decrease in thermal conductivity was also observed with increasing content of SBA and RHA in burnt clay bricks. Substitution of clay by 15% SBA and RHA in the production of burnt clay bricks reduced the thermal conductivity by 31% and 29%, respectively. Microscopic images also showed the presence of interconnected and irregular shaped open pores after addition of agricultural wastes in burnt clay bricks. Based on this study, it can be concluded that the utilization of SBA and RHA (up to 15% by clay weight) in manufacturing of burnt clay bricks is not only helpful in landfill reduction but also leads towards the development of sustainable and thermally efficient construction material.

О восстановлении нарушенных свалками и полигонами земель Саратовской области

The following thesis presents the data on violation of land in Saratov region landfills and solid waste landfills. Here was specified the direction of reducing the negative impact of wastes on the ecological conditions of territories, in particular a dual system of collection and recycling of waste, burning of solid waste incinerators, a significant reduction in landfills in the mandatory reclamation under them and the construction of landfills. Here was justified the importance of rational allocation, safe operation, reduce the risk of the negative impact of dumps and landfills on the ecological situation in the region is the development and implementation of GIS-monitoring of land disturbed and subject to violation as a result of storing solid waste. The principles of its creation and maintenance, the main of which are: the principle of hierarchy and complementarity, binding, temporal dynamics, complexity and geopotential.

Concept of sustainable waste management in the city of Zagreb: Towards the implementation of circular economy approach

ABSTRACTImprovement of the current waste management is one of the main challenges for most municipalities in Croatia, mainly due to legal obligations set in different European Union (EU) directives regarding waste management, such as reduction of waste generation and landfilling, or increase of separately collected waste and recycling rates. This paper highlights the current waste management in the city of Zagreb by analyzing the waste generation, collection, and disposal scenario along with the regulatory and institutional framework. Since the present waste management system mainly depends upon landfilling, with the rate of separate waste collection and recycling far from being adequate, it is necessary to introduce a new system that will take into account the current situation in the city as well as the obligations imposed by the EU. Namely, in the coming years, the Waste Framework and Landfill Directives of the European Union will be a significant driver of change in waste management practices and governance of the city of Zagreb. At present, the yearly separate waste collection makes somewhat less than 5 kg per capita of various waste fractions, i.e., far below the average value for the (28) capital cities of the EU, which is 108 kg per capita. This is possible to achieve only by better and sustainable planning of future activities and facilities, taking into account of environmental, economic, and social aspects of waste management. This means that the city of Zagreb not only will have to invest in new infrastructure to meet the targets, but also will have to enhance public awareness in diverting this waste at the household level. The solution for the new waste management proposed in this paper will certainly be a way of implementing circular economy approach to current waste management practice in the city of Zagreb.Implications: Municipal waste management in the developing countries in the EU (new eastern EU members) is often characterized by its limited utilization of recycling activities, inadequate management of nonindustrial hazardous waste, and inadequate landfill disposal. Many cities in Eastern Europe and Zagreb as well are facing serious problems in managing municipal wastes due to the existing solid waste management system that is found to be highly inefficient. The proposed scenario for city of Zagreb in the paper is an innovative upgrading of municipal waste management based on the waste management hierarchy and circular economy approach.

Economic assessment system towards sustainable composting quality in the developing countries

Reduction of landfills and dealing with the waste are among the key elements of the cleaner production and advanced environment policy. Composting represents one of the cleaner technologies in diverting organic waste from landfill. However, it has not been commonly practised in the developing countries due to low economic feasibility and environmental issues that arise from the abuse of compost quality. There are a lack of product standards and an indication of compost quality to govern its market and application. In order to foster public confidence in compost utilisation and as much as possible offset the operating cost, an economic assessment system is needed to benchmark the quality of the compost at a reasonable cost. In this study, a set of composting parameters and their analysis have been reviewed and ranked following their total scores in terms of relation to the agronomic value, technical complexity and analysis cost. The parameters were selected based on different assessment criteria. An assessment system developed on the base of the decision analysis comprises minimal analyses needed to assess the compost quality. The cost savings results from the presented work are illustrated by four scenarios: Scenario 1 served as the baseline to include all the necessary analyses and the remaining three (Scenarios 2, 3 and 4) had been evaluated by the developed assessment system. It is shown that the cost to assess the compost quality was reduced from 17 to 84 % depending on the type of input material and composting performance. The highest cost saving based on the analysis of compost quality reaching 84 % was achieved by Scenario 4 where composting was carried out using the segregated food and landscape waste. The assessment system could be very useful for improving the compost utilisation towards sustainable composting in the developing countries.

Municipal Waste-to-Energy plants in Poland – current projects

In 2016, six new municipal waste combustion plants will be operating in Poland. These projects, located in: Bialystok, Bydgoszcz, Konin, Krakow, Poznan and Szczecin, will influence waste management in Poland as well as change energy security of the country. So far in Poland only one Waste-to-Energy (WtE) plant, i.e. in the capital city of Warsaw, has been operating. Unfortunately, this is not enough, taking into account Polish economic development in the last years. Polish accession to the European Union (EU) significantly influenced the development of the industry which resulted in increased production of waste while the management system was not prepared to handle it in the proper way so there was a big amount of waste. The main way to deal with waste in Poland was, and still is, landfilling which can be in many ways dangerous for the environment. The EU law have put pressure on Polish Waste Management Systems and results are visible in currently realized Waste-to-Energy projects.This work analysis of the aforementioned 6 projects from economic (project value, funding from the European Union) and technological (used technology, waste throughout, availability etc.) point of view together with their impact on the entire waste management system and energy security. What is more, history of similar facilities in Poland is presented, what shows how many projects were prepared, how many fell through and time frame of finally realised projects (start of construction and the planned completion).Conclusions show why in the current situation development of Polish WtE infrastructure is right, i.e. operation of aforementioned plants that will ensure benefits associated with energy production, reduction of landfilling and informing public opinion regarding modern waste management models. Additionally, the article draws attention on the high responsibility that will be put on WtE plants operators and that experience gained during WtE implementation can be used to improve even further for future Polish Waste Management Systems.

Waste Management Pinch Analysis (WAMPA) with economic assessment

Conventional Pinch Analysis (PA) had been widely used d to define the target (demand chain) of a process system based on the information of stream quantities and quality (supply chain) for a micro-scale industries planning. With contrast to the conventional Pinch approaches, regional Solid Waste Management (SWM) strategy are often performed via optimisation tool which is often optimized in a blackbox optimization mathematical model. However, to enhance understanding and comprehension of the strategy, a visual technique like Pinch Analysis would be vital. A new application of Waste Management Pinch Analysis (WAMPA) for carbon emission was proposed to identify waste management strategies based on specified landfill reduction target and carbon emission target. This study used WAMPA methodology to analysis the effect of recycling target and cost reduction target towards waste management planning.

Solid recovered fuel: An experiment on classification and potential applications

The residual urban waste of Prato district (Italy) is characterized by a high calorific value that would make it suitable for direct combustion in waste-to-energy plants. Since the area of central Italy lacks this kind of plant, residual municipal waste is quite often allocated to mechanical treatment plants in order to recover recyclable materials (such as metals) and energy content, sending the dry fractions to waste-to-energy plants outside the region. With the previous Italian legislation concerning Refuse Derived Fuels, only the dry stream produced as output by the study case plant, considered in this study, could be allocated to energy recovery, while the other output flows were landfilled. The most recent Italian regulation, introduced a new classification for the fuel streams recovered from waste following the criteria of the European standard (EN 15359:2011), defining the Solid Recovered Fuel (SRF). In this framework, the aim of this study was to check whether the different streams produced as output by the study case plant could be classified as SRF. For this reason, a sampling and analysis campaign was carried out with the purpose of characterizing every single output stream that can be obtained from the study case mechanical treatment plant, when operating it in different ways. The results showed that all the output flows from the study case mechanical treatment plant were classified as SRF, although with a wide quality range. In particular, few streams, of rather poor quality, could be fed to waste-to-energy plants, compatibly with the plant feeding systems. Other streams, with very high quality, were suitable for non-dedicated facilities, such as cement plants or power plants, as a substitute for coal. The implementation of the new legislation has hence the potential for a significant reduction of landfilling, contributing to lowering the overall environmental impact by avoiding the direct impacts of landfilling and by exploiting the beneficial effects of energy recovery from waste.

Waste Management Pinch Analysis (WAMPA) for Carbon Emission Reduction

Improper waste management happened in most of the developing country where inadequate disposal of waste in landfill is commonly practiced Apart from disposal, MSW can turn into valuable product through recycling, energy recovery, and biological recovery action as suggested in the hierarchy of waste management. This study presents a novel method known as waste management pinch analysis (WAMPA) to examine the implication of recycling and landfill reduction target on the carbon emission. WAMPA aims to identity waste management strategies (waste to energy (WTE), recycling, reduce, reuse) based on specified landfill reduction target and carbon emission target. WAMPA is capable to examine the capacity of each strategy groups through graphical representation, and is also capable to provide meaning and illustration to the effect of changing of target toward the needs of each strategy.

Steel Slag as A Road Construction Material

Steel slag is a byproduct obtained from steel industry. It is generated as a residue during the production of steel. Because of the high disposal cost as a waste material and the overall positive features of steel slag, it has been declared a useful construction material, not an industrial waste by most of the developed countries. Successively, it is recycled as an aggregate for the construction of roads, soil stabilization, and base and for the surfacing of flexible pavement. Despite this, a large amount of steel slag generated from steel industries is disposed of in stockpiles to date. As a result, a large area of land is being sacrificed for the disposal of this useful resource. Many researchers have investigated the use of steel slag as an aggregate in the design of asphalt concrete for the road construction. The best management option for this by product is its recycling. This leads to reduction of landfills reserved for its disposal, saving the natural resources and attaining a potential environment. The purpose of this paper is to review the engineering properties of steel slag and its utilization for road construction in different ways.