Asphalt Mixing Plant Research Articles

Drum mix asphalt plant with knock-out box and separate coater

Asphalt plant apparatus comprising a drum dryer, a collection chamber or "knock-out box," a "baghouse," and a separate pugmill coater disposed directly underneath the collection chamber so that dust particles which settle out of the airstream in the collection chamber fall directly into the pugmill coater. The apparatus solves the problem of light-end hydrocarbon pollutants which can be stripped from liquid asphalt by contact with steam, in that the liquid asphalt is introduced not into the drum dryer but into the separate pugmill coater instead. Since no liquid asphalt is present in the drum dryer to coat and control the aggregate dust, the exhaust air from the dryer is more heavily dust-laden than that from a conventional drum mixer. However, the apparatus utilizes a collection chamber to compensate for the additional dust in the exhaust air by recovering part of that dust and dropping it directly into the pugmill coater, where it is mixed with the aggregate and liquid asphalt.

4375959 Waste heat recovery in asphalt mixing plant : Roger A. Powell; assigned to The McCarter Corporation

4375959 Waste heat recovery in asphalt mixing plant : Roger A. Powell; assigned to The McCarter Corporation

A probabilistic programming model for blending aggregates

The paper introduces the formulation of a probabilistic programming model to find the optimum mix proportion of aggregates to meet the specific grading requirement in order to minimize the cost which consists of the material cost and the expected penalty cost. The model is probabilistic since the gradation, which is the major parameter, is a random variable. A linear programming model is first formulated. Using the LP solution as initial value, a direct search technique is then employed to solve the problem. The model is expected to be applicable to any problem of aggregates blending. In this paper, however, the mixing aggregates of an asphalt mixing plant is exemplified to test the applicability of the model.

Der Einfluß von Asphaltmischanlagen auf die Vegetation unter besonderer Berücksichtigung der Erdölbitumendämpfe1

The influence of hot mix asphalt plants on vegetation with special regard to vapours from asphaltic bitumen. Vapours from asphaltic bitumen can be neglected as a factor injurious to plants because of the small amount generally exhaled by hot mix asphalt plants. Vegetation damage observed was due to sulfur dioxide, dust and soot. A method for identifying condensed vapours from asphaltic bitumen deposited on plant surfaces is discussed.

Epoxy Asphalt Concrete for Airfield Pavements

Epoxy asphalt concrete is suited for heavy loads, high temperature and velocity blast, and fuel spillage; it is combination of graded mineral aggregate and EPON asphalt binder; conventional hot mix asphalt plants and paving equipment are used in its production; material has Marshall stability of 20,000 lb and withstands tire pressure of 1000 psi and temperatures of 800 F.