Michael D Hawkins

US Patent:

6672751, Jan 6, 2004

Filed:

Jan 18, 2001

Appl. No.:

09/764687

Inventors:

Michael R. Hawkins - Kansas City MO 64157

International Classification:

B28C 546

US Classification:

366 25, 366 58, 34137, 432111

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.

US Patent:

7044630, May 16, 2006

Filed:

Jan 2, 2004

Appl. No.:

10/750927

Inventors:

Michael R. Hawkins - Kansas City MO, US

International Classification:

B28C 5/20
B28C 5/46

US Classification:

366 7, 366 25, 34137, 432111

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.

US Patent:

7357562, Apr 15, 2008

Filed:

Mar 11, 2003

Appl. No.:

10/386070

Inventors:

Michael R. Hawkins - Kansas City MO, US

International Classification:

B28C 5/46

US Classification:

366 23, 366 25

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. An optional secondary burner in the exhaust housing elevates the temperature of the exhaust gas above its dew point temperature before delivery to the baghouse.

US Patent:

7472877, Jan 6, 2009

Filed:

Feb 2, 2005

Appl. No.:

11/049100

Inventors:

Michael R Hawkins - Kansas City MO, US
William L Walkington - Peculiar MO, US
Lonnie D. Greene - Kansas City MO, US

International Classification:

A47F 5/00

US Classification:

24828831, 248 49

Abstract:

A multi-point support system with self-aligning trunnions to carry, on a cradle frame, a rotatable cylindrical drum having a pair of trunnion rings spaced along a central longitudinal axis. A thrust bearing connected to the frame engages a trunnion ring to accommodate any horizontal thrust load for an inclined cylindrical drum. Each self-aligning trunnion includes a base plate on which is mounted a trunnion roller with an axis of rotation substantially parallel to the central longitudinal axis of the cylindrical drum. A pair of bearing supports are connected to the base plate transversely with respect to the longitudinal axis of the drum in order to permit arcuate movement of the base plate about one bearing support and to permit tilting movement of the base plate about a transverse axis through the bearing supports. The arcuate and tilting movements of the base plate permit the trunnion roller to maintain full tangential contact with the trunnion ring.

US Patent:

7581871, Sep 1, 2009

Filed:

Jun 18, 2007

Appl. No.:

11/764727

Inventors:

Michael R Hawkins - Kansas City MO, US

International Classification:

B28C 5/46

US Classification:

366 7, 366 23

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. An optional secondary burner in the exhaust housing elevates the temperature of the exhaust gas above its dew point temperature before delivery to the baghouse.

US Patent:

61648094, Dec 26, 2000

Filed:

Nov 30, 1998

Appl. No.:

9/201687

Inventors:

Michael R. Hawkins - Kansas City MO

International Classification:

B28C 526

US Classification:

366 7

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. The dryer 50 and mixer 52 are arranged so that the longitudinal dryer axis and the longitudinal mixer axis lie in a common vertical plane where the mixer angle of declination may be adjustably varied to be less than, greater than or equal to the dryer angle of declination. A recycle feeder assembly 120 feeds recycle material to the mixer 52 between the discharge end of the dryer 50 and the first end of the mixer 52.

US Patent:

47879386, Nov 29, 1988

Filed:

Jun 30, 1986

Appl. No.:

6/879996

Inventors:

Michael R. Hawkins - Prairie Village KS

Assignee:

Standard Havens, Inc. - Kansas City MO

International Classification:

C09D 324
C08L 9500

US Classification:

1062811

Abstract:

A drum mixer asphalt plant is provided with a rotatable cylinder 10 in which virgin aggregate, recycle material and liquid asphalt are mixed to produce an asphaltic composition and the hot gas stream for heating and drying the materials flow in countercurrent relation. In a first zone within the cylinder 10, aggregates are heated and dried by heat radiation and a hot gas stream generated at a burner head 46 of a combustion assembly 40. In a second zone within the drum cylinder 10 isolated from the burner flame and hot gas stream by the combustion assembly 40, liquid asphalt is sprayed from an injection tube 76 to mix with aggregate materials. A recycle feed assembly 60 delivers recycle asphalt material to the second zone also for mixing with the aggregate and liquid asphalt.

US Patent:

56648812, Sep 9, 1997

Filed:

Nov 14, 1994

Appl. No.:

8/338333

Inventors:

Michael Hawkins - Kansas City MO
Robert E. Schreter - Roswell GA

Assignee:

Maxam Equipment, Inc. - Kansas City MO

International Classification:

B28C 122
B28C 546

US Classification:

366 4

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. The hot gas stream is withdrawn from the drum cylinder at the upstream or inlet end thereof and delivered by ductwork to air pollution control equipment.