Abstract: A shale oil modifier is made of a crude shale oil dehydrogenated sufficiently to attain a viscosity of between about 1200-1800 poise at 60.degree. C. The crude shale oil has sufficient basic nitrogen content so that the dehydrogenated crude shale oil exhibits non-Newtonian properties when mixed with asphalt cements. Preferably, the basic nitrogen content is about 2%-2.5% by weight. The shale oil modifier is made by a process which includes providing a crude shale oil and subjecting the crude shale oil to a two stage distillation followed by a vacuum distillation and collecting the residual fraction. The residual fraction is dehydrogenated with air until a select viscosity, preferably between about 1200-1800 poise at 60.degree. C. is obtained.

Abstract: A method for rejuvenating asphalt pavement includes milling and collecting a select thickness of asphalt pavement of a portion of an existing roadbed. A shale oil modified asphalt comprising between 5-25% shale oil modifier and 75-95% asphalt cement is provided. An aggregate comprising about 60-70% virgin aggregate and about 30-40% of the milled and collected asphalt is combined with the shale oil modified asphalt and then applied to a roadbed.

Abstract: A composition for rejuvenating asphalt comprises between 5-25% by weight shale oil modifier and between 75-95% by weight asphalt cement. The asphalt cement may consist of an AC-10 binder or an AC-20 binder. The shale oil modifier is made of dehydrogenated crude shale oil, the shale oil modifier exhibiting non-Newtonian properties when mixed with asphalt cements. A recycled asphalt pavement consists of the above-described rejuvenating composition and an aggregate composition comprising between about 30-40% recycled asphalt pavement and between about 60-70% virgin aggregate. A method for rejuvenating asphalt pavement includes milling and collecting a select thickness of asphalt pavement of a portion of an existing roadbed. A shale oil modified asphalt comprising between about 5-25% shale oil modifier and 75-95% asphalt cement is provided.

Abstract: A retorting apparatus including a vertical kiln and a plurality of tubes for delivering rock to the top of the kiln and removal of processed rock from the bottom of the kiln so that the rock descends through the kiln as a moving bed. Distributors are provided for delivering gas to the kiln to effect heating of the rock and to disturb the rock particles during their descent. The distributors are constructed and disposed to deliver gas uniformly to the kiln and to withstand and overcome adverse conditions resulting from heat and from the descending rock. The rock delivery tubes are geometrically sized, spaced and positioned so as to deliver the shale uniformly into the kiln and form symmetrically disposed generally vertical paths, or "rock chimneys", through the descending shale which offer least resistance to upward flow of gas. When retorting oil shale, a delineated collection chamber near the top of the kiln collects gas and entrained oil mist rising through the kiln.