Abstract: The present invention relates to a thawing-apparatus, in which a substance is preferably heated. The present invention further relates to a method to thaw a substance with radio-frequency waves.

Abstract: A method for producing an asphalt concrete blend that includes the steps of drying and heating aggregate in a single and only dryer, preferably via direct heating, and without use of a pre-dryer. The aggregate is then combined with asphalt cement, preferably via indirect heating, such that the blend has an asphalt cement components (ACC) percentage of at least 25% percent to form an aggregate mix. Liquid asphalt cement may also be added to the aggregate mix. Preferably, the asphalt cement content of the final asphalt concrete blend is provided by a maximum of 70% ACC. In certain cases, the asphalt cement content of the asphalt concrete blend is comprised of ACC and liquid asphalt cement.

Abstract: Detonable devices such as charged air bag inflators are fed to a shred tower at a controlled feed rate via a feed valve. Water spray and/or water baths in the shred tower prevent sparking and begin to solubilize chemicals while the inflators are fed to primary and optional secondary shredders respectively performing course and fine shreds. A sump receives the shredded material which continues solubilize and separate chemicals from metal. A conveyor lifts solids from the sump. Dewatered solids are fed to a receiving box for metal scrap recycling.

Abstract: In one aspect, the present invention relates to a coke drum module, the coke drum module includes a support frame. A coke drum is disposed within the support frame. A strut is removably connected to the support frame and the coke drum. The strut becomes unloaded responsive to the coke drum contacting a support pad. The coke drum module further includes a compression member removably connected to the support frame and the coke drum. The compression member is oriented generally perpendicularly to the strut. A rigid connection is present between the coke drum and the support frame during transportation of the coke drum module. Upon removal of the strut and the compression member, the rigid connection is not present.

Abstract: A hot mix asphalt (HMA) or warm mix asphalt (WMA) plant features material transfer by shear action of segmented screws and directional flights standing on an inner drum. Indirect convective material heating is initiated by a heating source located inside of the inner drum. Material mixing, heating, melting, and uniform coating, all take place as a single simultaneous process. As the result of processing, regular HMA (or WMA) or up to 100% RAP (or ARS) recycled HMA (or WMA) can be produced. Many heat sources, such as a conventional oil burner and the surface combustion burner, may also be utilized in the plant. The plant may be combined with paving units for an integrated, mobile paving system.

Abstract: The invention relates to a method and a plant for producing asphalt mixture and is directed in particular to the recycling of recovered asphalt. In order to achieve recycling of up to 100% recovered asphalt and to produce an asphalt mixture with the required quality, it is provided according to the invention that at least the drying and heating of the asphalt granulate and/or aggregates are carried out in a low oxygen atmosphere. The low oxygen atmosphere is achieved by supplying low oxygen gases with an oxygen content of maximum 10%, preferably with an oxygen content of maximum 5%. The conveyance of the heated and dried asphalt granulate and/or aggregates, the siloing and mixing with bitumen to form a new, incorporation-ready asphalt mixture also usefully take place in a low oxygen atmosphere.

Abstract: Hot asphalt recycling system having a mixing hopper where the hot aggregate, exiting the drier, and the RAP are mixed; a pouring hopper which is opened to said mixing hopper from one end thereof and from whose other end RAP is poured, in order to obtain recycled asphalt concrete which is to be used in the production of one of the asphalt layers by using RAP. Said system comprising an air inlet pipe whose one end is connected to the heat source and whose other end is opened to the pouring hopper in order to transfer hot air, which is heated by a heat source, inside the pouring hopper; and at least one drying box in order to provide the RAP inside the pouring hopper to be poured to the mixing hopper in a sequenced manner and step by step.

Abstract: Embodiments of the present invention generally relate to a warm mix asphalt assembly and methods of operating the same. More specifically, embodiments of the present invention relate to warm mix asphalt assembly having requisite ultra-low nitrogen oxide emissions. In one embodiment of the present invention, a warm mix asphalt assembly comprises a warm mix asphalt skid, having a water input pipe, a water output pipe and a control apparatus; a burner assembly for drying aggregate, the burner assembly comprising a water line for receiving water from the warm mix asphalt skid; and an asphalt expander and drum assembly having a water line for receiving water from the warm mix asphalt skid.

Abstract: A warm mix asphalt plant comprising a counter-flow drum, apparatus for precisely metering flows of A/C and water, an asphalt expander with no moving internal parts where a circular curtain of flowing clean water is mixed with a coaxial circular curtain of moving heated A/C to create asphalt foam which is heated and mixed inside a lower portion of the asphalt expander and then distributed to cover aggregate inside the counter-flow drum.

Abstract: Recycled asphalt product is heated within an indirectly heated recycled asphalt product heater by passing heated gases through heat exchange members within a drum while the recycled asphalt product is moved through the drum from one end to the other end of the drum. The heat exchange members provide conduits for the heated gases, the conduits extending from an inlet adjacent a source of heated gases to an outlet communicating with an exhaust, each conduit following a looped path and having two or more segments each with a longitudinal length extending from adjacent one end of the drum to adjacent the other end of the drum. The segments are arranged serially in a serpentine configuration, are generally parallel to one another, and are spaced apart radially within the interior of the drum.

Abstract: An HMA plant which uses incidental heating of metal surfaces in combination with hot exhaust gases to pre-heat and pre-dry virgin aggregate material contained in an enclosed container which permits hot dry air to pass through interstices in the virgin aggregate material stored in the container.

Abstract: A method and template are provided for modifying an asphalt dryer/mixer that includes an outer drum and an inner drum with a plurality of mixing paddles, the two drums forming an annular mixing chamber in which asphalt cement and aggregate materials are mixed. The template comprises a bracket marking portion that is adapted to locate one or more brackets on the inner drum and a paddle reference portion that is adapted to locate the bracket marking portion with respect to a mixing paddle. A mixing paddle to be referenced for locating a bracket is selected and the template is placed on the inner drum with the paddle reference portion referencing the selected mixing paddle. The template is used to mark the location of the bracket, the bracket is affixed to the outer surface of the inner drum at the bracket location marked; and an agitation strand is attached to the bracket.

Abstract: A method of operating a paving system includes establishing a plan for paving a work area which is based on a positional temperature model. The method further includes receiving temperature data for paving material and comparing the temperature data with data predicted by the positional temperature model. Operation of the paving system is adjusted where actual data differs from model predicted data. A paving system and control system are provided having an electronic control unit configured to compare electronic temperature data with a positional temperature model for paving material. The electronic control unit can control machines of the paving system based on comparing actual data with model predicted data, and can further update either or both of a plan for paving a work area and the positional temperature model itself based on differences between actual data and model predicted data.

Abstract: An HMA plant which uses incidental heating of metal surfaces in combination with hot exhaust gases to pre-heat and pre-dry virgin aggregate material contained in an enclosed container which permits hot dry air to pass through interstices in the virgin aggregate material stored in the container.

Abstract: A dryer (10) for an asphalt plant is disclosed. In one embodiment, the dryer (10) includes a generally cylindrical drum (12); a burner (20) having a burner head (22) at least partially disposed within the drum (12); a feeder (26) attached to a stationary portion of the dryer (10) for providing a recycled asphalt pavement; and an adjustable inlet (28) for introducing the recycled asphalt pavement from the feeder (26) into the drum (12) at a desired position. The adjustable inlet (28) is adjustable laterally between at least two positions.

Abstract: An apparatus for thermally treating concrete during transportation in a concrete mixer truck which includes a unit mounted on the chassis of the concrete mixer truck for providing at least one of a cooling and heating medium; a heat exchanging radiator assembly mounted adjacent to a concrete mixing drum of the concrete mixer truck and configured to receive at least one of the cooling and heating medium from the unit; and a mixing water tank mounted on the concrete mixer truck.

Abstract: A hot mix asphalt plant for producing hot mix asphalt using a high percentage of RAP comprising a first dryer adapted to receive and mix virgin aggregates and RAP fines and a first burner assembly adapted to produce a burner flame and heat and dry the virgin aggregates in the first dryer. The plant also includes a second dryer adapted to receive coarse RAP and a second burner assembly adapted to produce a burner flame and heat and dry the coarse RAP in the second dryer. The plant further comprises a pugmill adapted to receive the virgin aggregates and the RAP fines from the first dryer and the coarse RAP from the second dryer and mix the virgin aggregates, the RAP fines and the coarse RAP to produce hot mix asphalt.

Abstract: A milled materials processor consists of a self contained, stationary or fully mobile thermal process plant for the thermal processing of 100% recycled asphalt pavement into new hot mix paving material. Mobile units are designed for transportation by vehicle to a job site and rapid arrangement. For example, the milled materials processing unit at the standard legal load or non-permit load size and configuration processes approximately 25 tons per hour of pre-sized recycled asphalt pavement materials, approximately 50,000 lbs gross, having up to 3% moisture content. Larger unit sizes are available in transportable configurations of 10? wide×54? long, and 12? wide×62? long. Alternatively, units are designed and erected as stationary modular systems for higher tonnage capacities from approximately 200 tons per hour to approximately 400 tons per hour and higher.

Abstract: A counter-flow drum mixer asphalt plant equipped with a secondary feeder for introducing RAP to direct radiant heat of the combustion zone. Heated virgin aggregate and RAP in the combustion zone are delivered through a transition piece to a first stage of the mixing zone where liquid asphalt is combined with the materials and secondary combustion air flows through the first stage to evacuate blue smoke and steam back to the combustion zone. The second stage of the mixing zone is substantially isolated from secondary combustion air flow where dust and mineral fines are introduced and mixed to complete the asphalt product discharged from the mixing zone. Alternative constructions of the mixing zone are disclosed to provide the first and second stages having such characteristics, as well as options for both the passive and active control of the secondary combustion air.

Abstract: A rotating apparatus (10) for drying a material (44) is disclosed. In one embodiment, the rotating apparatus (10) includes a generally cylindrical drum (12), a burner (20) having a burner head (22) at least partially disposed within the drum (10) and a plurality of elongated flights (26). The flights (26) are spaced-apart at pre-determined locations along an interior surface (16) of the drum (12). The length of the flights extends along the interior surface (16) of the drum (12). Optionally, a plurality of plates (28) may be utilized and positioned between the plurality of flights (26) and the interior surface (16) of the drum (12).

Abstract: An Advanced Maritime Emissions Control System (AMECS) includes several Exhaust Intake Bonnets (EIBs) of different size and/or shape, an Emissions Capture System (ECS), and an Advanced Maritime Emissions Control Unit (AMECU) mounted on an Unpowered Seagoing Barge (USB). The EIB includes a cage formed by downward curved ribs, a shroud which is lowerable to cover the ribs, a belt near a lower edge of the EIB for retaining and sealing the EIB to a stack, and a mechanism for tightening the lower edge of the EIB (and thus the belt) around the stack. The ECS lifts one of the several EIBs onto the stack of an Ocean Going Vessel (OGV). Exhaust from the stack is drawn through a large diameter duct to the AMECU. The AMECU processes the exhaust through multiple treatment stages. The stages include pre conditioning the exhaust, oxidizing, reducing, polishing, and precipitating.

Abstract: A method for operating a counter-flow aggregate dryer for an asphalt plant in which primary aggregate materials are introduced into a first end of a horizontally rotating cylinder and travel to the second, discharge end of the cylinder through drying and combustion zones. Hot gases are generated in the combustion zone to flow in counter-current heat exchange relationship with the aggregate materials for discharge from the first end of the cylinder to air pollution control equipment. Secondary materials like RAP or virgin aggregates are fed directly into the combustion zone. The discharge gas stream is heated above its dew point prior to delivery to air pollution control equipment.

Abstract: An insulating flight for a dryer incorporates inner and outer plates with insulation between them. The concave surfaces of the inner and outer plates provide a space for the insulation and allow for thermal expansion without stressing the welds between the inner and outer plates.

Abstract: A hot-mix asphalt manufacturing system includes a counter-flow rotary dryer having a combustion chamber, an inlet for dry ingredients, an outlet for hot-mix asphalt, and a pollution control device. The pollution control system includes a pre-filter, a cooling device and a fiber bed filter. Combustion gases from the combustion chamber are directed onto the ingredients for the hot-mix asphalt without substantial introduction of excess air or recirculated air and contact the hot-mix asphalt at a temperature substantially equal to the temperature of the combustion gases. The pollution control system removes substantially all particulates and hydrocarbons from the emissions from the hot-mix asphalt ingredients.

Abstract: A counter-flow drum mixer asphalt plant equipped with a secondary feeder for introducing RAP to direct radiant heat of the combustion zone. Heated virgin aggregate and RAP in the combustion zone are delivered through a transition piece to a first stage of the mixing zone where liquid asphalt is combined with the materials and secondary combustion air flows through the first stage to evacuate blue smoke and steam back to the combustion zone. The second stage of the mixing zone is substantially isolated from secondary combustion air flow where dust and mineral fines are introduced and mixed to complete the asphalt product discharged from the mixing zone. Alternative constructions of the mixing zone are disclosed to provide the first and second stages having such characteristics, as well as options for both the passive and active control of the secondary combustion air.

Abstract: A system and method for reducing the emissions from a dust generation station, such as a metal cutting station, can be easily transported from location to location. The system uses a mobile carrier which supports a separator, such as a baghouse, as well as a telescopically adjustable duct. A hood, which is attached to the duct and serves to contain exhaust gases generated at the dust generating station, is capable of rotation about the hood pivot point. An exhaust fan serves to induce flow of the exhaust gas from the hood, through the duct and across the separator. A mobile, emission-free metal cutting system incorporates the system for reducing emissions as well as a mobile transport cutting machine.

Abstract: A rotary drum heater for mixing asphalt with a hot gas introduced into the drum by gas burners is disclosed. The drum has an inlet opening for material to enter the drum to be processed and an outlet opening for material to exit. The hot gas is blown into the interior of the drum and is diverted by a hot gas conduit segment that is designed to gently heat the asphalt.

Abstract: A counter-flow aggregate dryer for an asphalt plant is equipped with a secondary feeder for introducing RAP or virgin materials intermediate the ends of the combustion zone of the dryer. Nonveiling flights in the combustion zone shield material carried through the combustion zone from direct radiant heat and veiling flights in the drying zone create a curtain of falling aggregates heated by a hot gas stream flowing in a countercurrent direction from a primary burner. A secondary burner elevates the temperature of the exhaust gas above its dew point temperature before delivery to the baghouse.

Abstract: The present invention is to a method and apparatus for changing the flighting (20) within a mixing drum (12). A plurality of radially spaced apart doors or paddles (30) are connected to one of the two adjacent supports (60). Each door or paddle (30) is pivotally connected (35,34) to the interior (13) of the drum (12) and can be either open or closed depending on which fixed support (60) the door/paddle is connected to.

Abstract: A bag house is mounted on a portable trailer and has a tube sheet with depending filter bags in part defining a first plenum for receiving a gas stream with fines and a second plenum for receiving clean gas from the filter bags. The fines are collected in one or more hoppers below the filter bags. A screw conveyor in each hopper has reverse flighting adjacent opposite ends for conveying separated fines longitudinally along and from adjacent opposite ends toward a central location intermediate the length of the housing. An elevation conveyor having an inlet located in the central location conveys the collected separated fines out of the housing to an external outlet for discharge into a surge operator.

Abstract: An asphalt plant includes a plurality of asphalt processing components including a first set of components producing volatile emissions and a second set of components requiring process heat. A separate central burner assembly is adapted to supply heat energy in the form of heated gas to satisfy the process heat requirements of the second set of components. A first duct system is provided which includes a fan and which is adapted to capture a portion of the volatile emissions produced by the first set of components and to convey the captured emissions into the central burner assembly for mitigation. A second duct system is provided and includes a fan and is adapted to convey heated gas from the central burner assembly to the second set of components.

Abstract: A hot-mix asphalt manufacturing system including treatment of emissions and recirculated gases includes a counter-flow rotary dryer 12 having a combustion chamber 28, an inlet 24 for dry ingredients, an outlet 26 for hot-mix asphalt, and a plate collector 70 for treating recirculated gases. A fiber bed filter 90 (FIG. 5) is provided to remove hydrocarbons and particulates from the rotary dryer emissions before they are released into the surrounding environment. A cooling zone 92 is provided upstream from the fiber bed filter to cool the emissions to a temperature that is compatible with the fiber bed filter.

Abstract: A counter-flow aggregate dryer for an asphalt plant is equipped with a secondary feeder for introducing RAP or virgin materials intermediate the ends of the combustion zone of the dryer. Nonveiling flights in the combustion zone shield material carried through the combustion zone from direct radiant heat and veiling flights in the drying zone create a curtain of falling aggregates heated by a hot gas stream flowing in a countercurrent direction from a primary burner. A secondary burner elevates the temperature of the exhaust gas above its dew point temperature before delivery to the baghouse.

Abstract: A process for reclaiming salvaged asphalt includes feeding salvaged asphalt mixed with new sands, stones and tar in a designed proportion into a double-layer drying machine including inner and outer gyroscopic drums; indirectly heating the salvaged asphalt in the drying machine by using a plurality of burners disposed externally to dry the salvaged asphalt, the heat thus generated being recycled via a draft tube into the drying machine to further heat the salvaged asphalt until the tar in the mixture starts to soften at about 80° C.; and mixing the salvaged asphalt with tar to form rejuvenated asphalt product when they travel to the outer gyroscopic drum in which the temperature reaches and the temperature of the stones contained in the salvaged asphalt also reaches a temperature of 160° C. for fusion with the tar.

Abstract: A drum mixer for heating, mixing and drying an aggregate material, such as a mixture of recycled asphaltic pavement and virgin aggregate. The drum mixer includes an inclined drum having a first end and a second end. The drum forms a pre-heating/blending section adjacent the first end, a heating/mixing section adjacent the second end, and a heating/drying/mixing section therebetween. A feed assembly for feeding aggregate material, preferably having a high ratio of RAP material to virgin aggregate, is provided. The feed assembly feeds the aggregate material into the pre-heating/blending section of the drum for movement of the aggregate material sequentially through the pre-heating/blending section, the heating/drying/mixing section and the heating/mixing section. A burner assembly extends from the second end of the drum into the heating/drying/mixing section of the drum.

Abstract: A tireless rotatable asphalt mixer. The mixer is provided with a rotatable tubular cylindrical section that is suspended along an axis of rotation at bearing mounts. The apparatus is allowed to expand by way of fixing one bearing mount and allowing the other mount to float with respect to longitudinal elongation resulting from thermal expansion. In the mixer, heated aggregate, liquid asphalt cement, and aggregate dust are mixed to produce an asphalt composition. The asphalt cement injection point is adjustable longitudinally along the centerline of the mixer, by way of replacement of an asphalt cement injection tube with a substitute injection tube of a different length. Further, multiple asphalt cements of different compositions may be introduced into the mixer by means of additional injection pipes at the inlet end of the mixer. Recycled Asphalt Pavement (“RAP”) may be added to the mixer with heated aggregate through the inlet chute.

Abstract: A rotary aggregate elevator for use in an asphalt plant comprising a rotating dryer drum for drying aggregate having an inlet end and an outlet end, a rotating mixing drum having an inlet end and an outlet end, and further having an inlet for dried aggregate at its inlet end for receiving dried aggregate, an annular collar attached to the inlet end of the mixing drum for receiving aggregate discharged from the outlet end of the dryer drum, the annular collar having flights attached to its inner wall to lift dried aggregate to the inlet of the mixing drum as it rotates.

Abstract: A drum mixer for heating, mixing and drying an aggregate material, such as a mixture of recycled asphaltic pavement and virgin aggregate. The drum mixer includes an inclined drum having a first end and a second end. The drum forms a pre-heating/blending section adjacent the first end, a heating/mixing section adjacent the second end, and a heating/drying/mixing section therebetween. A feed assembly for feeding aggregate material, preferably having a high ratio of RAP material to virgin aggregate, is provided. The feed assembly feeds the aggregate material into the pre-heating/blending section of the drum for movement of the aggregate material sequentially through the pre-heating/blending section, the heating/drying/mixing section and the heating/mixing section. A burner assembly extends from the second end of the drum into the heating/drying/mixing section of the drum.

Abstract: An apparatus for making asphalt paving material includes a dust collection and distribution system by which aggregate dust that is collected during the heating and drying of aggregate may be introduced into the mixing chamber and distributed over a substantial portion of the area of the mixing chamber. By distributing the aggregate dust over a broader area of the mixing chamber than has been previously known, the mixing effort required to achieve a thorough blending of the dust into the mixture is reduced, and the quality of the asphalt paving composition is improved.

Abstract: A counter-flow asphalt plant with a separately controlled and operated dryer 50 and mixer 52 in which virgin aggregate, recycle material and liquid asphalt are mixed to produce an asphaltic composition. The dryer 50 is rotated by a variable dryer drive 58 about a central longitudinal dryer axis disposed at a dryer angle of declination. Within the dryer 50, aggregates are dried and heated by heat radiation and a hot gas stream generated at a burner head 112 of a combustion assembly 106 positioned inside the downstream end of the dryer 50. The downstream end of the dryer 50 is inserted within the first end of the mixer 52 for delivery of the heated aggregate. The mixer 52 is carried on a tiltable frame 54 and is rotated by a variable mixer drive 88 about a central longitudinal mixer axis disposed at a mixer angle of declination.

Abstract: An asphalt plant including a plurality of asphalt processing components, with a selected first set of the components producing volatile emissions and a selected second set requiring process heat energy. A central burner assembly is connected to the selected second set of components by an insulated duct system for providing heat energy to the second component set. A first duct system is adapted to capture a portion of the volatile emissions produced by the first component set and convey the captured emissions into the central burner for mitigation. The central burner is preferably a media burner incorporating flameless combustion technology as well as an adjustable internal fuel injection system, which results in safer and more controllable combustion. Even with captured fugitive emissions in the inlet air, the fuel injection system keeps the concentration of combustible materials well below the lower flammability limit.

Abstract: A method and apparatus for disposing of paper in an asphalt plant. The asphalt plant comprises a container for stone aggregate to be heated, a burner for producing a burner flame to provide thermal energy for heating the stone aggregate in the container, the burner being positioned relative to the container so that an open space is defined therebetween, and a supplementary burner positioned in the open space between the burner and the container. The supplementary burner includes a supplementary burner member for producing a supplementary burner flame to provide thermal energy for heating the stone aggregate in the container, an air supply connected to the supplementary burner member for providing a stream of air to the supplementary burner member, and a supply of paper connected to the air supply for introducing paper into the stream of air. The paper is introduced into the stream of air such that the paper is entrained in the stream of air and is substantially incinerated in the container.

Abstract: Portable-to-site apparatus is operative to produce ready-to-lay traffic-wear surfacing and/or road etc course materials. A drum-like container is supported for axial rotation within insulation walling of a heating chamber allowing front access to one end closure of the rotatable container and affording operative association with heating means for raising temperature of contents of the container by heat transfer through side walling of the container. Normal operation is with the container sealed and under appropriate control as to time, heating, even rotation. The container is frame-mounted for tilting to aid loading and/or unloading.

Abstract: An asphalt plant includes a rotary dryer, a rotary mixer, a conduit for transferring gas from the mixer to the dryer, and a flame arrester in the conduit adjacent to the dryer to prevent a fire from propagating from the dryer back through the conduit.

Abstract: An apparatus for the treatment of 100% reclaimed asphaltic pavement (RAP) uses low temperatures and no direct radiation from a burner flame to the RAP. The RAP is first heated in a counter flow drum which is supplied with hot combusting gases generated by a remote low NOx burner. The temperature of the drum input gases is preferably around 1100 degrees F and the output temperature of the gases may be 100 degrees F or less greater than the input temperature of the RAP. The RAP may be heated with a microwave oven to raise the RAP to a final temperature, although this step is not absolutely necessary in the counterflow design of this invention.

Abstract: The counterflow drum mixer includes an elevated virgin aggregate inlet end and an opposite asphaltic product discharge end. A burner lies intermediate the ends and defines a combustion volume. Shield flights surround the combustion volume defining an annular chamber with the drum wall. Recycle material is supplied to the annular chamber at the upstream end of the combustion volume for heating by convection and conduction in the annular chamber. The virgin aggregate material flows through a drying zone, into the combustion volume and between the shield flights into the annular chamber for contact with and conductive heating of the recycle material. Radiant heat transfer from the combustion volume along radii of the drum to the annular chamber is prevented.

Abstract: A recycled asphalt product (RAP) drying apparatus comprising a three-zone counterflow RAP dryer and a duct system to recycle essentially all of the hot gases back through the system. The three-zone RAP dryer has a combustion zone at one end, a drying zone at the other end, and a buffer zone between the combustion and drying zones. A RAP inlet to introduce RAP into the dryer is included at one end of the drying zone, and a RAP outlet to remove RAP from the dryer is included at the other end of the drying zone. A duct pathway routes hot air from the drying zone back to the buffer zone so that hot air may be recycled through the apparatus.

Abstract: An asphalt plant for producing asphalt paving, the asphalt plant including: a) a dryer unit for heating stone aggregate, the dryer unit including a container and a burner for producing a flame to provide thermal energy for heating the stone aggregate in the container; b) a supply of burner fuel for providing fuel for the burner flame; c) a supply of burner air for providing oxygen to the burner flame; and d) the dryer unit including a grate which is spaced from the burner, the grate defining a plurality of openings, such that the burner flame extends through the openings, and such that the grate improves the thermal efficiency of the dryer unit for heating the stone aggregate.

Abstract: A drum mixer is provided with a rotatable cylinder in which aggregates, reclaimed asphalt pavement and liquid asphalt are mixed to produce an asphaltic composition. The drum cylinder includes a first region, in which virgin aggregate is heated and dried by heat radiation and the stream of hot gases produced by a burner flame flowing in countercurrent flow to the aggregate itself to establish a highly beneficial heat transfer relationship. A second region doubles as combustion and mixing zones. In the mixing zone the reclaimed asphalt pavement and liquid asphalt is added and mixed with the aggregates. The combustion zone is formed along the center of the mixing zone by an elongated combustion assembly disposed along the central axis thereof. The combustion assembly and chamber extend from the discharge end of the drum through the mixing zone to the heating and drying zone to segregate the hot gases from the asphalt, thereby preventing degradation of the final product.

Abstract: A system for concurrently remediating contaminated soil and producing hot mix asphalt includes a single inclined rotary drum; a burner assembly with a burner head spaced intermediately within the drum and oriented to direct a flame and hot gas stream upstream therefrom; a secondary air tube for providing atmospheric air to the burner head for supporting combustion; a drying zone with veiling flights upstream from the burner head for receiving, drying and heating virgin aggregate; a combustion zone with combustion flights downstream from the drying zone and upstream from the burner head for receiving and remediating contaminated soil by heat transfer from the virgin aggregate, the flame and the hot gas stream and for oxidizing volatile contaminants vaporized from the contaminated soil; an isolated mixing zone for receiving various materials including the virgin aggregate, the remediated soil, recycle asphalt, and certain constituents for producing hot mix asphalt therein from thermal energy contained within th