Factors Affecting Productivity of Refuse Compactor Vehicles in India

Shift towards mechanization in the municipal solid waste management (MSWM) is aimed at improving health wellbeing of the workers who are manually handling waste. With huge investment and operating costs, proper evaluation and monitoring of the performances of these equipment is essential. Identifying and rating the factors which impact the performance of equipment is the first step towards improving efficiency of a system. This research identifies the critical factors and issues in the operation optimization of refuse compactor vehicles. Interviews with experts and field studies helped in identification of 30 factors which were divided in five categories. The research uses analytical hierarchy process (AHP) for finding out the priority vectors of thus identified factors and categories. The study also highlights equipment selection parameters for the best suited model and make.

DecoMSW: A Methodology to Assess Decomposition of Municipal Solid Waste for Initiation of Landfill Mining Activities

Biochemical decomposition of municipal solid waste (MSW) in landfills leads to the generation of leachate, gases and humus substances. In this context, a methodology to assess D ecomposition of MSW, designated as DecoMSW, has been developed; based on a series of tests conducted on samples of the fresh MSW and those retrieved from the active bioreactor landfill (BLF) cells of age from 13 to 48 months. Furthermore, spatial and temporal variation in the (i) physical (composition) and (ii) chemical (pH, volatile solids, total organic carbon, elemental analysis, ammonium and nitrate-nitrogen, biomethanation potential, lignocellulosic content) characteristics of the MSW samples exhumed from the landfill have been established. Finally, these characteristics were correlated vis-à-vis the respective values of the fresh MSW. From this exercise, it has been observed that except for nitrate-nitrogen, all other chemical parameters of MSW decrease exponentially with time until 20 months, and beyond that, they remain constant, which is an indication of stabilization of MSW. In short, it has been demonstrated that DecoMSW is instrumental in assessing the state of decomposition of MSW with respect to time in the BLF and facilitates initiation of the landfill mining activities.

Analysis of Socio-demographic Factors Influencing Households Participation in Sustainable Food Waste-management in Malaysia

Most local authorities in Malaysia spent as much as 60-70 percent of their annual budget to dispose food waste together with other municipal solid wastes to landfills. It is time for Malaysians to start reducing food waste through sustainable method, as it is becoming an uphill task to manage food wastes generated in Malaysia. When households reduce the amount of food waste generated in a sustainable way, it could help reduce cost, and other related bills for households, and as well in running their other daily activities. The main objective of this study is to assess how sociodemographic factors of households in Selangor and Terengganu influence their behaviour towards participation in sustainable food wastes management program. The study applied purposive nonrandom sampling consisting of 333 respondents, 257 were from Selangor and 76 from Terengganu. Primary data was collected through structured questionnaire. Descriptive and logistics regression model analysis were used to analyze the data. Findings have shown 48.7 percent of Terengganu respondents spent not more than RM100 on food per week, while Selangor had 41.2 percent within the same period who spent such amount. 35.4 percent of Selangor respondents spent between RM101-200 compared to Terengganu which spent same amount at 30.3 percent within the same periods. The survey shows 43.2 percent of Selangor households disposed 1-3kg food wastes, while Terengganu on the other hand had 51.3 percent who disposed same quantities of food wastes per week. Respondents with higher education, those on government jobs, small family size and ethnicity have significant impacts on the respondents' behaviour towards participation in sustainable food waste management program. Note: US$1=RM4.09

A Systematic Review on Fenton Optimization for Leachate Treatment Via Response Surface Methodology from 2005 to 2015

The high polluting potential and variable content of the landfill leachate makes it a significant source of environmental contamination. Advanced oxidation processes (AOPs) such as Fenton process, arises as leachate treatment. Application of response surface methodology (RSM) from previous literatures evaluates the synergistic effects of independent variables to optimize the Fenton process. This paper presents systematic review on articles published from 2005 to 2015 reported on optimum conditions of Fenton treatment landfill leachate treatment using RSM. Papers were selected from different database according to defined inclusion criteria and then, evaluated. The best conditions identified were: pH around 3, [H2O2]/[Fe2+] molar ratio from 2.38 to 24.00, [H2O2]/[CODraw leachate] mass ratio around 1 and reaction time from 30 min to 331.2 min. All models presented R2 > 0.75, indicating a good correlation between the experimental data and the values predicted by the models.

Analyzing the Reuse Potentials of Landfilled Solid Wastes for Farm Water Treatment and Reuse

The increasing solid waste management problems in developing countries necessitated landfill mining to determine the reuse potentials of landfilled solid waste materials. In this study, characterization of landfilled solid waste obtained from a closed landfill site in Malaysia was conducted to ascertain its reuse potentials for biodegradation in wastewater treatment. The results revealed adequate neutral pH, Moisture Content of 34 %, Organic Content of 10.4 % and Bacterial Population in terms of Total Coliform of 8.3 × 105 CFU/100 mL, which are ideal conditions for biodegradation while porosity n of 51%, allow free flow of water during treatment. The SEM showed irregular shapes and pore spaces and a BET surface area of 3.376 m 2 g-1 which enables adsorption of pollutants on its surface, air diffusion and re-aeration. Furthermore, the waste material was used as media for biodegradation in a lab-scale bioreactor at a hydraulic loading of 4 L m-3 d-1 and inflow rate of 0.1 L min-1. The results showed maximum removal rates of 95, 97, 86, 70, 70, and 98% for COD, BOD, TSS, TDS, NH3-N, and TP respectively. Utilization of this technology as bioreactor landfills will solve landfill congestion and also provide cheap wastewater treatment option.

The Effect of the Calcination Temperature on the Physical, Chemical and Mineralogical Characteristics of Sugar Cane Bagasse Ash (SCBA) for Use As Pozzolan

Statement of Novelty: This study analyzes the influence of the washing process and the calcination temperature on the morphological, physical, chemical and mineralogical characteristics of SCBA. The objective of the present study is to evaluate the morphological, physical, chemical and mineralogical characteristics of sugar cane bagasse ash (SCBA). The ashes were obtained by calcination of sugarcane bagasse (SCB), a waste product generated by the sugar and alcohol industry, at temperatures of 500°C, 600° C and 700°C, and the influence of this calcination on the pozzolanic activity of SCBA. The techniques used to characterize these ashes include helium gas picnometry, sedigraphy, scanning electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffractometry (XRD) and Fourier transform infrared spectrometry (FTIR). The evaluation of the pozzolanicity of these ashes was carried according to chemical titration method as proposed by Fratini, modified Chapelle method and finally using the pozzolanic activity index (PAI) with cement. The results showed that the SCBA presented high pozzolanicity, regardless of the calcination temperature.

Trends in the Use and Recovery of Electronic Waste As Aggregates in Eco-friendly Concrete

The management of electronic waste (e-waste) mainly from televisions and computers, has turned into an environmental issue due to the increased demand in the electronics sector and the highly toxic contents (mercury, lead, or cadmium) of some of these devices that make them almost unrecoverable. Therefore, these valuable devices become wastes disposed of in landfills. Worldwide, some scholars have proposed recycling methods that re-introduce these wastes streams in the manufacturing process of heavy concrete, pavement, concrete blocks, and clay bricks among other unconventional products. The replacement rates of virgin materials with recycled e-waste fluctuate according to the type of waste. Nevertheless, the use of e-waste generates a positive environmental impact due to the less demand for virgin materials such as river sand and gravel. This study aimed to review the current e-waste recycling state-of-the-art such as circuit boards (PCB), high-impact polystyrene (HIPS), cathode ray tube (CRT), and LCD screens. A systematic review of scientific literature published in the last 10 years (2010–2019) was done through the SCOPUS database. The results showed a maximum potential replacement rate of 40% for this type of waste, given the effect on the physical and thermomechanical properties of the concrete.

Various Models Used in Analysing Municipal Solid Waste Generation–A Review

At present, factors such as growth in population, economic development, urbanization and improved standard of living increase the quantity and complexity of generated Municipal Solid Waste. The different approaches for developing models for forecasting municipal solid waste generation have been classified into conventional and non-conventional or artificial intelligence models. While the conventional models include sample survey, system dynamics, econometric models, time series analysis, factor driven models and multiple linear regression models, the non-conventional models include artificial neural networks, Fuzzy logic models and Adaptive Neuro Fuzzy Inference System models. In this review, various factors considered for modelling, locations of study, sources of data and various studies conducted by researchers have been tabulated in detail for identifying the major factors and models used in developed and developing countries. Non-conventional models are being preferred because of their capacity to analyse dynamic data and for their prediction accuracy.

Effect of Water Reducing Admixtures and Construction Variability in Concrete Containing Recycled Aggregate Concrete

The objectives of this project are to evaluate the effect of water reducing admixtures and construction variability in concrete mixtures containing recycled concrete aggregate (RCA). A concrete mix that was approved for curbs and sidewalks in the State of Florida was selected. Based on the analysis conducted, it was found that properties of the RCA were comparable to the virgin aggregate used in this project. However, the absorption of the RCA was double as compared to the limestone. Although the compressive strength of the virgin mix was decreased by 19% when RCA was introduced into the mix, both mixes met the target strength (17.2 MPa). Admixture has a significant impact on all the mixes, especially on mixes that contained RCA. When admixture was omitted, the 28-day compressive strength dropped to nearly 55% on the mixture containing RCA. In addition, the RCA mix without the admixture did not reach the target strength at 28 days. Similarly, construction variability has a significant effect on the compressive strength of the mixes. When the RCA content was increased by 15% and 25% respectively, the concrete paste was weak. These mixtures did not meet the target strength at 28 days.

Suitability of Shale Treated with Palm Kernel Shell Ash and Pulverized Palm Kernel Shell As Landfill Liners at Nguzu Edda, Southeastern Nigeria

Wastes are mostly disposed of in landfills, which pose threat to soil and groundwater as a result of percolation of leachate. Therefore, barrier soils are required for the lining of a landfill to prevent seepage of leachate into the surrounding groundwater system. In this regard, the suitability of ten shale samples treated with 0-12 % (increments of 2 %) proportion of palm kernel shell ash (PKSA) and pulverized palm kernel shell (PPKS) by dry weight of the shale samples were evaluated for uses as landfill liner. The samples were subjected to series of geotechnical tests to determine the index properties, and strength characteristics of the natural and treated shale using West African standard (WAS) and Modified AASHTO (MAS) compactive energy levels for comparison purposes. The shale was classified as A-7-5. The atterberg limits test results show that liquid and plastic limits generally decreased, while the plasticity index (PI) increased with increase in PKSA and PPKS contents. The results also demonstrated that maximum dry density (MDD), volumetric shrinkage strain (VSS) and hydraulic conductivity decreases significantly while optimum moisture content (OMC) increases with increase in PKSA and PPKS contents for the both energy levels. The maximum strength of 380.30 and 448.70 KPa were recorded at 4 % of the stabilizers. The findings affirmed that the samples met the requirements for landfills liner, although PPKS was more effective than PKSA for both energy levels. Moreover, the addition of PKSA and PPKS to liners can also be an alternative means of its disposal.