Stabilization/Solidification - 4.0 Technology Selection

4.0 S/S Technology Selection

The selection of S/S technologies is based on several factors (Wiles, 1987):

• Waste characteristics (both chemical and physical)

Waste characteristics are the most important factor in determining S/S treatment technology. See section 5 for further discussion.

• Process type and processing requirements

The types of S/S activity (in-drum, in-plant, etc.) and processing requirements (waste modification, mixing models, waste transportation/storage) should be considered during selecting a S/S technology. For example, in-drum or in-plant processes are more easily controlled than in situ process. (Wiles, 1987)

• S/S product management objective

The S/S product can be disposed in a landfill, stored, or transported elsewhere. According to regulatory requirements, the S/S products for landfill disposal and for delisting may not require the same degree of treatment. Delisting requires that the waste materials are no longer hazardous, while disposing in a RCRA hazardous waste landfill does not. (Wiles, 1987)

• Regulatory requirements

There are numerous regulations relevant to S/S processes, such as the EP, MEP, TCLP, and chemical reaction requirement for waste treatments, but these are not performance criteria which S/S products must meet. Generally, a designer will produce an S/S waste product meeting minimum requirements, i.e. removing free liquids and/or produce a solid which can be transported or stored. (Wiles, 1987)

• Economics.

The cost of different S/S methods will be discussed in following parts in detail.