Asphalt plants, sulfur dispersion

Sulfur Dispersion in Asphalt Plants. Sulfur-extended binder and Thermopave mixes were prepared in several batch type commercial hot-mix plants to verify the effectiveness of aggregate shear on sulfur dispersion during mixing in the pugmill. The influence of the following variables on the dispersion of sulfur was assessed. 

This verifies that aggregate shear during mixing is effective in dispersing sulfur in commercial hot-mix plants. Addition of asphalt and sulfur to the pugmill simultaneously would permit the manufacture of sulfur-extended binder mixes at the usual mixing cycle time. 

Thermopave mixes use substantially higher sulfur contents. Microscopic examination of mixes prepared in the laboratory and in a commercial Cedarapids hot-mix plant verified that some of the sulfur is finely dispersed, therefore contributing to the dilution of the asphalt, but most of the sulfur agglomerates readily to perform as a mix stabilizer. 

The process developed by SNPA involves a dispersion of sulfur in asphalt to form a sulfur/asphalt (S/A) binder. This S/A binder is then used to produce hot-mix paving mixtures with conventional mix-plant and paving equipment. 

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