|
UTILIZATION OF COAL FLY ASH FOR THE PRODUCTION OF ARTIFICIAL AGGREGATES AS A CROP GROWTH MEDIUM WITH
ACIDIC “KUNIGAMI MAHJI” SOILS IN OKINAWA-JAPAN
G.Y. Jayasinghe* and Y. Tokashiki ABSTRACT
The escalating world wide production of coal fly ash and its respective costs of disposing create
an urgent need to find potential utilization methods in order to avoid disposal as land fillings. Development of synthetic light weight aggregates
(SLWA) with coal fly ash and used paper can be regarded as an unconventional method for ash utilization which is being not much addressed. This
study examined the properties of SLWA developed by coal fly ash ,used paper and starch as a binder and their utilization as a soil amendment to
improve the crop production in acidic ,low productive `Kunigami Mahji` soils in sub tropical Okinawa, Japan.
M. El-Hoz, Ph.D. ABSTRACT
The objective of this study is to evaluate the municipal solid waste composting plant which is
implemented in Lebanon with a capacity of 300 tons per day of organic material. Samples from the compost produced were analyzed in the laboratory to
check for quality assurance where standards for physical properties were set for this composting plant. Based on the results obtained, the
moisture content was higher than the required limit. Therefore, review of the bottlenecks of the composting process should be made to improve the
quality of the compost. The generated leachate during the fermentation and maturation processes is treated. The technique is based on biological
treatment by aeration and physical / chemical treatment by flocculation and coagulation. The results indicate that the effluent quality is not
meeting the original design parameters and the treatment process is ineffective. Therefore, a new plan for another process is needed. It can be
concluded that composting of municipal solid waste can present more than 50% reduction of the total amount of solid waste generated. Moreover,
apart from effecting resource recovery and reduced cost of ultimate disposal, to utilize MSW compost in the country, market-driven standards and
regulations should be met.
USE OF DUST WASTE FROM GRAIN STORAGE FACILITIES FOR SOIL STABILIZATION AND MOISTURE RETENTION
Omer Mughieda
Jamal Abu-Ashour ABSTRACT
Large amounts of dust waste are produced during loading and unloading of grains in the grain
storage facilities. This powder-like material imposes a serious health hazard to workers as well as to neighboring communities. Reuse of this waste
can be a feasible management option. This study investigates two possible uses of this grain dust waste: (1) to enhance the geotechnical properties
of expansive soils and (2) increase the capacity of soils to retain moisture. Expansive soils constitute the most costly natural hazard to buildings
and civil engineering structures. In order to stabilize these soils, grain dust waste was mixed with two local expansive soils from northern Jordan
at different percentages ranging from 0 to 8% by mass. The two soils from Irbid and JUST were classified as CH and MH, respectively, according to
the Unified Classification System. The experimental work involved investigating the Atterberg limits, unconfined compressive strength, direct shear
strength, standard Proctor density, and swell pressure. The results showed that the dust waste decreased the plasticity index, dry density, and the
unconfined compressive strength. It was also found that the swell potential was reduced by up to 58% and the swell pressure was reduced by up to
54% to 75% with the upper range limits corresponding to the Irbid soil. Slow direct shear tests indicated that the stabilizing agent decreased the
cohesion intercept while the angle of internal friction was increased by up to 19% to 45%. The findings of this study indicate that the use of grain
dust waste is promising as a soil stabilizer and is a viable option of material utilization. The capacity of both soils to retain moisture under
suction pressures ranging from 0 to 15 bars was tested in a pressure plate extractor. Moisture retention capacity increased significantly when 4
and 8% of grain dust waste were mixed with these soils at all pressures. Irbid soil had higher moisture retention capacity than JUST soil. The
grain dust waste has a potential application for preserving moisture in agricultural soils. The addition of 8% of grain dust waste to soil will not
have adverse effects on the quality of the water leaching through the dust waste-soil mixture. Similar pH and EC values were measured in two
solutions containing soil-grain dust waste mixture and soil only.
DEVELOPMENT AND ANALYSIS OF WEAR RESISTANCE MODEL FOR COMPOSITES OF ALUMINIUM REINFORCED WITH RED MUD
S.S. MAHAPATRA
AMAR PATNAIK
M.S. KHAN ABSTRACT
The expeditious advancement in the past decades has resulted in the need for new multifunctional
materials that possess characteristics not obtainable from any individual materials. Recent studies reveal that metal matrix composites reinforced
by SiC and Al2O3 particles, whiskers and soft fibers, have significantly better characteristics such as super wear resistance, high strength and
low density than unreinforced materials. However, prohibitive costs and stability of properties pose challenge for the researches in the process of
development of composites. To address these issues, composites are being developed using waste materials as reinforcement for effective utilization
of industrial wastes.
INFLUENCE OF CONTAMINANT SOURCE NODE SPACING AND DISPERSIVITY ON DETECTION CAPABILITY OF GROUNDWATER
MONITORING NETWORKS
Paul F. Hudak ABSTRACT
Effects of contaminant source node spacing and dispersivity on the detection capability of
groundwater monitoring networks were evaluated. The analysis considered five-, seven-, and nine-well networks near a rectangular landfill located
100 m from a buffer zone boundary, a distance limit within which contaminants should be detected. Various combinations of source node spacing,
longitudinal and transverse dispersivity, and contaminant source width were input to a computer model, which computed the detection capability of
groundwater monitoring networks. Varying contaminant source node spacing from 1 to 10 m had little effect on the capability of monitoring networks
to detect contaminants released from the landfill. Similarly, over a range of 0.2 to 10 m, longitudinal dispersivity had little effect on the
detection efficiency of any monitoring network. By contrast, changing transverse dispersivity had considerable effect on detection capability of
monitoring networks. For a longitudinal dispersivity and contaminant source width of 1 m, increasing transverse dispersivity from 0.1 to 0.2 m
increased detection efficiency by 8 to 20%. This study suggests that transverse dispersivity should be carefully evaluated for site
specific-conditions, and groundwater monitoring strategies should emphasize uncertainty in this parameter.
HEAVY METALS IN FLY ASHES: POTENTIAL IMPACT ON FLY ASH DERIVED COAGULANTS
Maohong Fan, Robert C. Brown & Yonghui Shia
J(Hans) van Leeuwen
ABSTRACT
This research analyzed the distribution of fifteen trace elements from thirty-two fly ash samples
collected from four countries. The inductively coupled plasma/ mass spectrometry analyses of acid extracts show that concentrations of heavy metals
in fly ashes vary from one country and power plant to another. Coagulants produced from these fly ashes need to be analyzed and tested to prevent
levels of heavy metals that are higher than desirable in wastewaters treated with these.
|
