Transforming Municipal Solid Waste into Construction Materials

Utilization of compost and GGBS in the manufacturing of light-weight concrete - characteristics and mechanical properties

Generation of solid waste and its improper disposal approaches poses severe threat to the environment, animals, and the human community which may affect the ecosystem. The generation of waste by the human community cannot be avoided but the impact from it can be minimized in various ways. One such approach is to utilize the by-products obtained from the waste through proper techniques and methods. So, in this paper, an attempt is done to use compost as a replacement for M sand and to check its feasibility in manufacturing light-weight concrete. Also, ground granulated blast furnace slag (GGBS) is used as a replacement for cement whereas pumice stone is used as the coarse aggregate. Initially, the physical, chemical, and microstructural properties of the raw materials are studied. Then, the concrete specimens are casted for M25 grade and the specimens are tested for compressive strength at 7 and 28 days of age. It is observed that the GGBS at 10% for cement and compost up to 20% for M sand showed higher compressive strength which is sufficient for light-weight concrete. Hence, it can be said that the utilization of compost can minimize the waste disposal and it can be managed effectively.

The use of urban biowaste and excavated soil in the construction sector: A literature review

Soil has been used as building material for thousands of years with a decrease in popularity after the industrial revolution. Nowadays, there is a growing interest in the implementation of unfired soil-based building solutions for their low environmental impact, performances and availability. Traditional soil construction techniques have recurrently included vegetal fibres to enhance soil performance and recent studies highlight a predominant use of agro- and non-agro-waste for unfired soil construction. The article reviews the state-of-the-art of the use of excavated soil and biowaste in the construction industry including a novel focus on urban-only waste and on building technologies using the integration of these two secondary construction material flows. Our literature review highlights a lack of references about the joint use of these secondary resources. Finally, future research orientations are suggested to promote their implementation in the building sector, which could improve urban waste management.

Case Study of Municipal Waste and Its Reliance on Reverse Logistics in European Countries

The authors have examined municipal waste, its components and their integration with reverse logistics processes. Background: The theoretical part begins with a definition of municipal waste. Later, the integration between municipal waste and reverse logistics is provided, including presentation of the hierarchy of qualitative methods and models. Methods: The authors constructed a correlation matrix and applied a dynamic regression model to identify that the level of municipal waste impacts recycling of biowaste which demands reverse logistics. Results: The authors provided a dynamic regression model which could be applied for forecasting the size of recycled municipal waste into biowaste indicated in European Union countries. Conclusions: The variety of components in municipal waste prevents the increase of the recycling rates and has to be changed to ones that have higher recycling rates.

Complex Processing of Saponite Waste from a Diamond-Mining Enterprise

The solution of the sludge utilization problem and yield increase at processing plants have great importance today all over the world. Disasters associated with the tailings dams failures have madeus develop technologies of tailings sludge utilization as a commercial product, reducing the environmental damage on the regions of mineral extraction. This research aimed to provide new data, methods and an analytical approach to solve the saponite sludge accumulation problem on mining enterprises with silicate coagulant to increase the rate of cycle water clarification for the enrichment process and the recycling of sludge to reduce its hazardous effect. Samples were taken in the deposit located in the north of the European part of Russia, where diamond bearing ore contain montmorillonite minerals, mostly saponite, which is considered to be a perspective secondary product. The content of this mineral in the sludge is above 20 wt.%. Saponite is a clay mineral with the general chemical formula (Ca,Na)0.3(Mg, Fe2+)3(Si, Al)4O10(OH)2·4H2O. The mineral has high adsorption, ion exchange, and catalytic and filtration properties; due to the developed diffuse layer, saponite particles are highly stable in an aqueous medium—the resulting suspension is highly stable and has slow sedimentation. During the research, a positive effect on the sedimentation process of clay saponite particles was established, due to the introduction of a coagulant containing 70% tricalcium silicate, at a dosage of 2 g/dm3 coagulant; the degree of purification of water containing the saponite clay suspension is 99%. The condensed sediment after the thermal drying and with the limestone addition can be used again as a coagulant or secondary product with enhanced properties;therefore, the sludge will be processed, and not stored.

The Complexity of Space Utilization and Environmental Pollution Control in the Main Corridor of Makassar City, South Sulawesi, Indonesia

Population mobility, increasing demand for transportation, and the complexity of land use have an impact on environmental quality degradation and air quality pollution. This study aims to analyze (1) the effect of population mobility, increased traffic volume, and land use change on air quality pollution, (2) direct and indirect effects of urban activities, transportation systems, and movement patterns on environmental quality degradation and air pollution index, and (3) air pollution strategy and sustainable urban environmental management. The research method used is a sequential explanation design. Data were obtained through observation, surveys, in-depth interviews, and documentation. The results of the study illustrate that the business center and Daya terminal with a value of 0.18 µgram/m3 is polluted, the power plant and Sermani industrial area with a value of 0.16 µgram/m3 is polluted, the Makassar industrial area with a value of 0.23 is heavily polluted, and the Hasanuddin International Airport area with a value of 0.04 µgram/m3 is not polluted. Population mobility, traffic volume, and land use changes have a significant effect on environmental quality degradation, with a determination coefficient of 94.1%. The direct effect of decreasing environmental quality on the air pollution index is 66.09%. This study recommends transportation management on the main road corridor of Makassar City, which is environmentally friendly with regard to sustainable environmental management.

Incentive Mechanism for Municipal Solid Waste Disposal PPP Projects in China

In municipal solid waste disposal public–private-partnership (PPP) projects, economic benefits, as well as social and ecological benefits, are critical in sustaining sustainability development. However, private investors may make more efforts for economic benefits than for social and ecological benefits out of self-interest. Because the government does not have the same information that the investors have, information asymmetry leads to opportunistic behavior. To solve these problems, principal–agent models were established to analyze the incentive mechanism for encouraging investors to adopt a positive attitude toward both economic benefits and social and ecological benefits, inhibiting investors’ opportunistic behavior. In particular, numerical simulation was carried out to analyze the relationships between related parameters (c1,c2,ct,a,β,k,λ,p). The results show that the investors with higher comprehensive abilities are more willing to make efforts for social and ecological benefits. An increase in incentive and governance intensity would help to encourage investors to make more efforts for project benefits and to lower the level of opportunistic behavior adopted by investors. The complexity of the task and the fuzziness of the perception of effort input results aggravate the uncertainty and risk of the projects due to information asymmetry. Therefore, real-time and positive incentives are important. In order to ensure the social and ecological benefits of a project, performance standards should be set according to the actual situation; investors prefer fixed compensation with lower risk, but fixed compensation does not have incentive effect, and the proportion should not be too high.

Waste-Derived Nanoparticles: Synthesis Approaches, Environmental Applications, and Sustainability Considerations

For the past few decades, a plethora of nanoparticles have been produced through various methods and utilized to advance technologies for environmental applications, including water treatment, detection of persistent pollutants, and soil/water remediation, amongst many others. The field of materials science and engineering is increasingly interested in increasing the sustainability of the processes involved in the production of nanoparticles, which motivates the exploration of alternative inputs for nanoparticle production as well as the implementation of green synthesis techniques. Herein, we start by overviewing the general aspects of nanoparticle synthesis from industrial, electric/electronic, and plastic waste. We expand on critical aspects of waste identification as a viable input for the treatment and recovery of metal- and carbon-based nanoparticles. We follow-up by discussing different governing mechanisms involved in the production of nanoparticles, and point to potential inferences throughout the synthesis processes. Next, we provide some examples of waste-derived nanoparticles utilized in a proof-of-concept demonstration of technologies for applications in water quality and safety. We conclude by discussing current challenges from the toxicological and life-cycle perspectives that must be taken into consideration before scale-up manufacturing and implementation of waste-derived nanoparticles.