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MECHANICAL PROPERTIES OF HYDROTHERMALLY TREATED ALUMINA-SILICA RICH INDUSTRIAL WASTE CEMENT
SYSTEMS — EFFECT OF MAGNESIA ADDITION
B. Liu, A. Ray, P.S. Thomas, D. Klimesch and J.P. Guerbois
ABSTRACT
The utilisation of industrial waste products such as fly ash, blast furnace slag and fired clay-brick, as supplementary cementing materials to produce blended Portland cement (PC) has increased worldwide in recent years. The incentive was directed towards the utilisation of wastes and industrial by-products in order to minimise PC consumption, thus reduce CO2 emissions. This study aims to investigate the potential of magnesia (MgO) as a supplementary material in combination with alumina-silica rich fired clay brick waste fines. Compressive strength results showed adverse effects on the additions of brick waste fines and MgO. However, for blended PC with the addition of both brick waste and magnesia, an apparent synergy, indicating a minimising of strength reduction, was observed. X-ray diffraction (XRD) data revealed the presence of brucite, a hydration product of MgO, in the MgO blended PC suggesting a lack of pozzolanic activity of MgO.
STUDIES ON HYDRAULIC TRANSPORTATION OF SEWAGE SLUDGE — FLY ASH MIXTURE SLURRY
P.K. Senapati
D. Panda
A. Parida
The present investigation highlights the transport characteristics of sewage sludge –
fly ash mixture to be used as top soil in barren agricultural land for enhancing its fertility. Both mineralogical and rheological
studies have been carried out. Mineralogical studies indicated the constituents imparting fertility to the soil. The rheological
characteristics of the mixture slurry have been determined in a Haake RV100 rheometer at overall slurry concentration between 30-50% by
weight. The slurry showed pseudo plastic behaviour within the range of study. The head loss of the mixture slurry has been determined by
applying Torrance equation. Based on the results, the basic design parameters for transporting 0.5-1 million tones of total dry solids
(fly ash and sewage sludge) per annum have been worked out.
EVALUATION OF EFFECT OF VOLUME AND LENGTH OF JUTE ON MECHANICAL PROPERTIES OF ASPHALT CEMENT
AND ASPHALT CONCRETE
Dr. Yusuf Mehta, P.E., Associate Professor
Jute is grown extensively in south Asia. It serves as a critical source of income for
poor farmers in the region. It is however still under utilized and a lot is wasted. Since jute fibers have a strong tensile strength,
they may have a potential to arrest and reduce crack growth. Since asphalt binder in asphalt concrete is the weakest component, the
properties of jute and its effect on cracking performance of asphalt binder needs to be evaluated. However, as the jute is increased to
replace the binder, beyond a certain point insufficient binder may cause poor cohesion between the two materials. The purpose of this
study is to evaluate its potential as a reinforcing material in asphalt concrete. In this study, fiber strength, fiber density,
absorption rates, and jute-binder bond strength were determined. Subsequently, beams of asphalt binder were made from varying
concentrations and lengths of jute, and its flexural strength and flexural stiffness were measured at -10ºC, 0°C and 10ºC. Asphalt
concrete specimens were also tested in indirect tensile mode with a predetermined amount of jute at 10°C. The effect of jute on the
mechanical properties of asphalt binder and asphalt concrete were evaluated. The results presented in the paper provide the properties
of jute and its influence on cracking resistance of asphalt binder and asphalt concrete.
AGRONOMIC PROPERTIES AND HEAVY METALS CONTENT IN SOIL RECLAIMED FROM MUNICIPAL SOLID WASTE
LANDFILL DEVELOPMENT OF A KNOWLEDGE–BASED SYSTEM FOR FOUNDRY WASTE RECYCLING
Somkid Prabpaia, Ph.D. (Public Health) Program, Faculty of Public Health
Michael R. Moore
Landfill soils reclaimed from municipal solid waste landfill were characterized for
agronomic properties and heavy metals. The samples were collected from Khon Kaen Municipality engineered landfill, Khon Kaen, Thailand,
approximately aged 10-15 years, and screened with a 6.3-mm sieve. Chemical properties analysis was undertaken by appropriate procedure,
and heavy metals were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass
spectrometry (ICP-MS). The landfill soil characteristics measured include pH, electrical conductivity (EC), cation exchange capacity
(CEC), organic matter (OM), total N, available P, K, Mg and Ca; results obtained were 8.1, 4.2 dS/m, 4.4 cmol/kg, 4.9%, 0.27%,
23.2 mg/kg, 1.24 g/kg, 10.5 g/kg and 0.43 g/kg, respectively. The heavy metal contents in landfill soil included 2.0 As, 3.25 Cd, 3.3 Co,
38.0 Cr, 166.0 Cu, 1533.0 Fe, 0.72 Hg, 412 Mn, 22.0 Ni, 157.0 Pb, 1.0 Se, 44.0 Sn and 662 Zn mg/kg, respectively. These heavy metal
concentrations were within permissible limits for land application described by Thailand and US EPA. This result indicated that
municipal solid waste landfill had potential for recovery soil, and its use for soil amendment.
SOLID WASTE MANAGEMENT OPTIONS FOR A DEVELOPING MEGA CITY — NAIROBI, KENYA
Thomas E.O. Odhiambo
Xiujin Li
Henry K. Rotich
Simon Osembo
Waste generation, both domestic and industrial, continues to increase world-wide in
tandem with growth in consumption. In developed countries, per capita waste generation increased nearly three-fold over the last two
decades, reaching a level five to six times higher than that in developing countries. With increases in populations and living standards,
waste generation in developing countries is also increasing rapidly, and may double in volume in the current decade. If current trends
continue, the world may see a five-fold increase in waste generation by the year 2025. A high proportion of the waste could be recycled
by the urban poor generating income for themselves and protecting the environment. There is a need to develop an integrated approach
where the public, private and community sectors work together to develop local solutions promoting sustainable solid waste management
hence sustainable development in a typical developing country like Kenya. This article is therefore based on a case study of solid waste
management and options for a typical fast developing mega city in the developing world, Nairobi the capital city of Kenya.
DEVELOPMENT OF CERAMIC COATINGS USING RED MUD — A SOLID WASTE OF ALUMINA PLANTS
Alok Satapathy, S.C. Mishra
P.V. Ananthapadmanabhan and K.P. Sreekumar
Plasma Spraying is a surface modification technique that combines particle melting,
rapid solidification and consolidation in a single process. But as high cost of spray grade powders limits the adoption of this
technique, exploring newer and cheaper materials suitable for plasma spray coating has drawn a lot of attention. This work reports an
attempt to spray coat red mud (the waste generated in alumina producing plants) on different metal substrates. Plasma sprayed coatings
of red mud have been developed at different operating power levels of the plasma gun on aluminium and copper substrates. Coating
adhesion strength and deposition efficiency were studied at various operating conditions. Characterization of the coatings includes
micro hardness measurement and scanning electron microscopy (SEM). It was observed that the operating power appreciably influences the
coating adhesion strength and coating thickness. Coatings deposited at very low and very high power levels show poor adhesion. Maximum
interface adhesion strength of ~8MPa was recorded at operating power of 12 kW. This work establishes ‘red mud’ as a potential coating
material, which may be suitable for wear resistant applications. It also suggests a value added utilization of this industrial waste.
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