Abstract:
An asphalt drum mixer (10) includes a rotating drum (12) within a fixed sleeve (32) which defines an annular chamber (34), and mixing tips (50, 58) mounted on the drum and in the annular chamber. The mixing tips (50, 58) pass through the hot mix asphalt laying in the bottom of the annular chamber (34) and mix and shear the hot mix asphalt and increase its residence time in the drum mixer (10). In one embodiment, the mixing tips may comprise curved scoop-like elements (50) which lift the hot mix asphalt higher than conventional paddles and greatly increase residence time of the mix in the drum (12) over conventional paddles. The quality of the mix is thus greatly improved. In another embodiment the mixing tips may comprise curved scoop-like elements (58) having slots (64) which greatly increase sheering of the hot mix asphalt, thereby further improving the quality of the mix.
Abstract:
A rotary heating device (20) having reduced NOx emissions including a recirculation system for recirculating gases downstream of a baghouse (12) to the heat source, such as a flame burner (28), and to a quenching ring (40) located at the end of a refractory combustion chamber (32) surrounding the burner flame (30). The addition of the recirculating gas to the burner (28) provides a cooler, turbulent flame (30). The addition of the recirculating gas via the quenching ring (40) to the end of the flame (30) reduces the length and temperature of the flame (30). The cooler, shorter, turbulent flame (30) provides sufficient heat for drying aggregate or for producing asphalt-aggregate mix while decreasing the production of NOx.
Abstract:
Reclaimed asphalt aggregates are produced in a process, comprising the steps: a) providing reclaimed asphalt lumps and treating the reclaimed asphalt lumps by the use of impact to obtain reclaimed asphalt aggregates that comprise recycle bitumen; and b) separating the reclaimed asphalt aggregates into at least a coarse fraction having granular particles with a diameter of more than 2 mm and at least a fine fraction having granular particles with a diameter of at most 2 mm. The reclaimed asphalt aggregates may be separately used in a process for the preparation of an asphalt composition.
Abstract:
L'invention concerne un dispositif de fabrication de produits enrobés à chaud, par exemple avec du bitume, comprenant : - un four comprenant une enceinte (2) mise en rotation, ladite enceinte (2) étant pourvue d'une entrée principale destinée à recevoir des produits granuleux, et d'une sortie (30), lesdits produits granuleux circulant de l'entrée principale vers la sortie, - un moyen de chauffe définissant une section de combustion (5) dans l'enceinte (2) et générant un flux de séchage, ladite enceinte (2) se poursuivant par une section de séchage (6) puis par une section de malaxage (7), caractérisé en ce que l'enceinte (2) est pourvue d'un système d'évacuation (12) des granulats chauds, ledit système (12) étant intégré entre la section de séchage et la section de malaxage et étant positionable entre une position active et inactive.
Abstract:
The invention relates to industrial equipment for the hot recycling of asphalt mixes and to the recycling method. The equipment comprises: a portable bank of hoppers which are used to meter RAP and unadulterated stone materials; a conveyor belt provided below the hopper bank in order to receive the material and transport same to a rotary cylinder including an industrial open-flame burner that is used to transmit heat energy indirectly to the RAP and to the supply of unadulterated stone material; a tank for storing a mixture of asphalt and rejuvenating agent enhanced with polymers, which is metered towards the rotary cylinder; a recycled asphalt mix lifting system which conveys said mix to a discharge silo; a combustion gas extractor; a fuel storage tank; and a weight measuring element at the inlet of the rotary drum.
Abstract:
A thermatic torpedo for preparing and delivering reinstatement materials has an internal chamber defining at least one compartment for containing graded aggregate and a second compartment for containing a stabilising agent, an external skin for insulating the contents of said internal chamber, a cap or lid for securely containing the contents of the torpedo in which is located at least one telescopic probe which can be driven through the compartments to heat and/or mix the contents thereof and at least one aperture through which the reinstatement materials may be expelled for delivery to a work site.
Abstract:
Die Erfindung betrifft ein Verfahren und eine Anlage zum Herstellen von Asphaltmischgut und ist insbesondere auf die Wiederverwendung von Ausbauasphalt gerichtet. Um eine Wiederverwendung von bis zu 100% Ausbauasphalt zu erreichen und ein Asphaltmischgut mit der erforderlichen Qualität herzustellen, ist erfindungsgemäß vorgesehen, dass wenigstens die Trocknung und Erhitzung des Asphaltgranulats und/oder Gesteinskörnungen in einer sauerstoffarmen Atmosphäre durchgeführt wird. Die sauerstoffarme Atmosphäre wird durch Zuführung von sauerstoffarmen Gasen mit einem Sauerstoffgehalt von maximal 10%, bevorzugt mit einem Sauerstoffgehalt bis maximal 5%, erreicht. Zweckmäßigerweise erfolgt auch die Förderung des erhitzten und getrockneten Asphaltgranulats und/oder Gesteinskörnungen, die Silierung und die Vermischung mit Bitumen zu einer neuen, einbaufertigen Asphaltmischung in einer sauerstoffarmen Atmosphäre.
Abstract:
A rotary drier for plants for the production of bituminous macadams with the use of recycled materials comprises a hollow rotary cylinder (2), heating means (9) connected to one end (4) of the cylinder (2), an aggregates infeed section (7) connected to one end (3), (4) of the cylinder (2), and a dried material outfeed section (8) connected to the other end (3), (4), an insertion section (24) for inserting recycled material into the cylinder (2), the insertion section being connected to an intermediate portion of the cylinder (2). The inside of the cylinder (2) is axially divided into a first, convection heat exchange zone (12), equipped with material tipping blades (14), and into a second, radiation and conduction heat exchange zone, and the cut material insertion section (24) is positioned inside the first heat exchange zone (12). A first group (25) of tipping blades (14) is mounted circumferentially inside the cylinder (2) between the insertion section (24) and the second heat exchange zone (13).
Abstract:
An improvement is provided for controlling the temperature of recycled asphalt product being processed in an indirectly heated recycled asphalt product heater, and the temperature of component parts of the heater itself, as the recycled asphalt product progresses through the heater and is heated by heat transferred from gases at an elevated temperature passed through the heater. Temperature sensors are placed at strategic locations within the heater and provide temperature information to a central processor arranged to receive information pertaining to temperature from the temperature sensors and to process the information and generate control signals. A controller arrangement controls the temperature of the heated gases entering a heat exchange arrangement within the heater in response to the control signals such that the temperature of the recycled asphalt product and the temperature of component parts of the heater are maintained within a desired predetermined range of temperature.