Migration of Hazardous Substances through Soil. Part 4. Development of a Serial Batch Extraction Method and Application to the Accelerated Testing of Seven Industrial Wastes

摘要

The initial objective of this work was to measure the leachability of selected wastes and determine the attenuation characteristics of certain soils. But, because the distribution of an ion between a waste leachate and a soil depends upon the composition of the leachate and the prior history of the soil (both of which change as leaching progresses and as more soil is penetrated), it was necessary to develop an experimental approach capable of simulating this dynamically-changing situation. Samples of wastes were collected from the following industries: zinc-carbon battery manufacturing, titanium dioxide pigment production, hydrofluoric acid manufacturing, white phosphorus production, oil re-refining, and two from zinc secondary-refining (cinders and scrubber-waste). Water extracts of these wastes were applied to Chalmers, Davidson, and Nicholson soils. The analysis of the resulting solutions for pH, conductivity, and concentrations of specified hazardous ions before and after contact with these clay soils allowed calculating distribution coefficients penetration factors, the fraction of each ion retained on the soils, the amount flushed off from a soil by the passage of a later extract, the yield of an ion per unit weight of waste, and the amount of an ion penetrating and retained by a unit weight of soil.