Utilization of high calcium fly ash as a substitute for limestone in agricultural soils

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5950559

Hodgson, L M

The nature of fly ash and its utilization on agricultural soils is discussed based on a review of 68 publications. Several experiments are described in which the neutralization potential of calcium-rich fly ash and its effects on soil physical and chemical properties were determined. Various concentrations of HCl were mixed with fly ash. The pH and solution concentrations of Ca, Mg, and Al were measured after two weeks, and again after six months. Results showed that the neutralization curve for fly ash contains three buffer plateaus, each of which corresponds to dissolution of one of the elements measured. The sum of the total Ca and Mg concentrations for the fly ash was a good predictor of its total neutralization capacity. Interactions between fly ash and soil were studied using four mine spoil materials with vastly different properties and an almost neutral silt loam. Changes in pH and EC with ash amendment rate and time, and the effects of amendment rate on hydraulic conductivity, bulk density, one-third bar water retention, and leachable cations were examined. Soil pH increased with increasing addition of fly ash. Changes in EC, hydraulic conductivity, and leachable cations were strongly influenced by soil properties. Changes in one-third bar water content were slight at realistic addition rates.

• OSTI ID: 5950559
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010800* -- Coal
Lignite
& Peat-- Waste Management
29 ENERGY PLANNING, POLICY, AND ECONOMY
290500 -- Energy Planning & Policy-- Research
Development
Demonstration
& Commercialization
294001 -- Energy Planning & Policy-- Coal
ACID NEUTRALIZING CAPACITY
AEROSOL WASTES
ALKALINE EARTH METALS
ALUMINIUM
ASHES
CALCIUM
CHEMISTRY
ELEMENTS
FLY ASH
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
MAGNESIUM
MATERIAL SUBSTITUTION
METALS
PH VALUE
RESIDUES
SOILS
WASTE PRODUCT UTILIZATION
WASTES
WATER CHEMISTRY