Combined spray drier
US 1782822 A
Description (OCR text may contain errors)
Now 25, 1930. s. HECHENBLEIKVNER 1,732,822
COMBINED SPRAY DRIER AND un'lmn Filed may 1a, 19?
` BY 21 y AT RNEYS l v Patented Nov. 25,1930
d, A UNITED STATES PATENT OFFICE INGENUIN HECHENBLEIKNER, OF CHARLOTTE, NORTH CAROLINA, ASSIG-NOR, BY MSN'E ASSIGNMENTS, TO CHEMICAL CONSTRUCTION CORPORATION, A CORPORATION OF DELAWARE COMBINED SPRAY DRIER-AND BURNER Application led May 18, 1927. Serial No. 192,463.
This invention relates to a spray drying apparatus, and more particularly to a combined spray drier and burner.
Heretofore it has been the common practice 5 in the art to place a spray forming device l centrally of a large drying chamber and preferably near the ceiling wall of said chamber, the spray forming apparatusbeing operated to forml a mist or a spray which substantially The ceiling wall of the chamber is provided with passages or openings through which hot gases are introduced into the chamber to dry the spray or mist formed within the chamber. It has been the ractice hitherto to heat the drying gases in urnaces or other heating apparatus at points removed'from the drying chamber and to conduct the hot gases from said furnace to the drying chamber. This is always accompanied by large heat losses and in addition thereto it .necessitates av plurality of installations occupying considerable space. It is the object of the present invention to provide a unitary apparatus which is compact in construction and simple in operation to accomplish both the heating of the gases and the drying of the spray with the resulting elimination of the greater portion of the heat losses and resulting in a greater eiciency of operation of the entire system.
These objects are accomplished by rovid'- ing an enclosure which is partitions into a 'combustion chamber' and a drying chamber, the partition being made of fire brick and being provided with a large number of passages to permit the passage of the `hot gases formed in the combustion chamber intov the drying chamber.
In the drawings, Fig. 1 is a sectional view of yan installation embodying the present invention, Fig. 2 is a side view of said installation,
Fig. 3 is a top view of the apparatus, and Fig. 4 is a sectional view of a modified form of the apparatus.
Referring to Fig. 1, 10 represents a large cylindrical enclosure made of heat resisting .material and provided with an opening 11 in the bottom thereof. 12 is a. rotating scraper which serves to feed the dry `powder formed fills at least the upper half of the chamber.v
in the drying chamber to the screw conveyor 13.
The enclosure 10 is provided with an arched ceiling 14 made of fire brick and is additionally provided with a partition 15 also made of fire brick which is disposed a short distance below the ceiling 14. The partition 15 thus divides the enclosure 10 into a dryin cham-i ber 16 and a combustion chamber 1 The cylindrical casing 18 is mounted centrally of the walls 14 and 15 and projects into.- the 'drying chamber 16 and is insulated from the combustion chamber by means of the layers of heat insulating material 19. The spraying device 20 which is operated by the motor' 21 is supported within the casing 18. The pipe 22 feeds the liquid to the spraying device 20.A The casing 18 is open at its top and forms a cold air inlet for the spraying apparatus which passes through the gas heating chamber or combustion chamber. This casing 18 is heat insulated from the combustion chamber by the aforesaid heat insulating material 19. With this construction cold air may be drawn into the spray head and this is utilizable for 'purposes as describedA by me in my copending application Serial No. 192,464 filed of even ldate herewith. A A platform 23 surroundsthe enclosure 1'0 at approximately the level of the partitioning wall 15 and supports a plurality 0f fuel burners 24 which enter the apertures 25 in the outer wall of the combustion chamber 17. The platform 23 also supports the distributing pipe 26 which substantially surrounds the enclosure 10 and is connected to any source of fuel supply which may be of any nature but is preferably a generators. The short vertical conduits 27 serve to connect the fuel distributing conduit 26 with each of the fuel thereto. d
The air conduit 28 is disposed over the top of the enclosure 10 and has connected thereto air feed pipes 29 which serve to lfeed air from 28 is also connected by means of a plurality of conduits 31 to openings 41 in the ceiling gaseous .fuel obtained from gasburners 24 and supply` K wall 14 of the combustion chamber to supply cold air thereto which is to be heated by the heat of combustion. A blower 32 serves to maintain a predetermined pressure of air in the conduit 28 so as to maintain the necessary flow of air through the feed pipes 29v for the burners as Well as to maintain a suithe drying chamber 16 to dry the spray formed therein and to cause the precipitation of the dry powder.
In addition to the heat resisting material which constitutes the wall of the enclosure 10, the outer wall of the combustion chamber 17 is additionally provided with another layer of heat resisting material 34.
In operation, the blower 32 maintains a predetermined pressure of air in the conduit 28 and causes the distribution of that air through the burners 24 to support combustion of the fuel that enters said burners by way of the fuel distributing conduit 26 and also serves to supply the necessary amount of air which enters the combustion chamber 17 by way of the conduits 31. The hot air as well as the combustion products pass into the drying chamber 16 by way of the passages 33 and perform the function of vaporizing and drying the fine spray or mist and causing the precipitation of a dry, finely divided powder which is carried out by means of the scraper 12 and the screw conveyor 13. y
If desired, instead of causing the apparatus to be operated under super-atmospheric pressure, the apparatus may be operated by suction, as shown in Fig. 4. Under these conditions the air conduit 28 is eliminated and a suction blower 40 is connected at a point near the bottom of the drying chamber 16 which serves to draw air from this atmosphere surrounding the enclosure 10 through the burners 24 as well as through the openings 41 in the ceiling wall 14 of the combustion chamber.
A number of advantages result from the apparatus above described, among which may be mentioned the following:
1. By means of the apparatus described herein, a very uniform distribution of the hot air and gas mixture thoroughout the drying chamber is obtained which leads to a higher drying capacity for a chamber of given size and to a higher heat eiiciency of the entire apparatus. v
2. An installation designed in acordance with the embodiment of the invention disclosed herein results in a saving of the original installation and in a saving of space occupied by the installation.
3. The heat losses are reduced to a minimum and the operation costs of the apparatus are substantially reduced.
4. The construction is simple and the cost of repairs is thereby reduced.
It will also be apparent that While I have shown and described my invention in the preferred form, many changes and modifications may be made in the structure disclosed without departing from the splrit of the invention, delinedvin the following claims.
I claim: i
1. A combined spray drying and gas combustion apparatus built into a unitary structure comprising a spray drying chamber having an apertured upper wall, and a combustion chamber disposed immediately thereover for generating and supplying hot gases to said drying chamber through said apertured upper wall.
2. A combined spray drying and gas combustion apparatus built into a unitary structure comprising a spray drying chamber having an apertured upper wall, a combustion chamber disposed immediately thereover for enerating and supplying hot gases to said rying chamber through said apertured upper wall, and a spraying apparatus disposed centrally of said wall and projecting into said drying chamber.
3. A combined spray drying and gas combustion apparatus built into a unitary structure comprising a spray drying chamber having an apertured upper wall, and a combustion chamber disposed immediately thereover for supplying hot gases to said drying chamber through said apertured upper wall, said combustion chamber being provided with gas inlets, and a cold air inlet for said spraylng apparatus passing through said combustion chamber.
4. A combined spray drying and gas combustion apparatus built into a unitary structure comprising a spray chamber having an apertured upper wall, a casing mounted centrally of said wall, a spraying apparatus mounted in said casing and projecting into the spray chamber, and an annular combustion chamber surrounding said casing for generating hot gases and for supplying the same to said spray chamber through said apertured wall.
5. A combined spra drying and gas combust-ion apparatus bui t into a unitary structure comprising. a spray drying chamber having an upper wall having a plurality of apertures distributed over a large area thereof, an air heating chamber disposed immediately thereover for generating hot ases and supplying the same to said drying c amber, and a spraying apparatus disposed centrally of said wall and pro'ecting into said drying chamber through sai apertured wall.
6. A comb-ined spra drying and gas combustion apparatus ui t into a unita structure comprising a spray drying cham r having an' apertured upper wall, an annular gas heatin chamber disposed immediately thereoveror supplying hot gas to said dry-l ingchamber, said gas heating chamber being lprovided with gas inlets, and a cold air inlet for said s raying apparatus passing centrally throng said annular gas heating chamber. Y 7. A combined spra drying and gas comu -bustion apparatus bui t into a unitary structure comprlslng a spray chamber having an upper wall having a plurality of a rtures distributed over a large area thereo a casing mounted centrally of said'wall, a spraying apparatus mounted in said casing and projecting into the spray chamber, and an annular gasproducing chamber surrounding said casing to supply hot gas to said spra chamber through said apertured u per wal lzo 8. A combined s ra drying an gas combustion apparatus ui t into a unitary structure comprising a fuel supply pipe, an air supply ipe, a combustion chamber, aburner dispose 1n said combustion chamber, means for supplying fuel and air under ressure to said burner, a spray drying cham r, a wall having passages thereinpermitting the hot gases to pass from said"combustion chamber t'o said spray chamber disposed between@ said i A chambers, and a spray 'drier located at said chamber.
9. A combined spra drying and gas combustion apparatus bu` t into a unitary strucwall and extending into said spray drying I 35, ture comprising an enclosure, a wall separating said enclosure into a combustion chamber v and a drying chamber, said wall havin a plurality of passages therein burners ',sposed in said vcombustion chamber, means for o supplying air and-fuel under pressure to said burners, and a spray drier located at said wall and extending into said spray drying chamber.
Signed at Charlotte, in the county of Mecklenburg and State of North Carolina,
this 16th dav of MaHyA. D. 1927. A INGENUIN CHENBLEIKNER.