US1412642A - Pulverized-fuel-feeding system - Google Patents

Description

w. 0. SAMSLER.

PULVERIZED FUEL FEEDING SYSTEM. APPLICATION FILED APR. 19. I918.

1A1 2 642., Patented p 11, 1922.

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4- a? w L I 5 5 6 I W & la 1 232 29 M A 7 2 8 L I S w WITNESSES w. 0. AMSLER. PULVERIZED FUEL FEEDING SYSTEM.

APPLICATION FILED APR. 19; 1918.

1,4111 2,6420 Patented p 11, 1922.

2 SHEETSSHEET 2.

WITNESSES I ferred to application,

. United States t rtar caries.

WALTER O. AMSLER, 0F

EDGEWOOD, PENNSYLVANIA.

PULVERIZED-FUEL-FEEDING SYSTEM.

Application filed April 19,

To all whom it may concern? Be it known that I, WALTER O. AMsLER, acitizen of the .United States, residing at 'Edgewood, in the county of Allegheny and State of Pennsylvania, have invented certain new -and useful Improvements in Pulverized-Fuel-Feeding Systems, of which the following is a specification.

My invention relates to new and improved means for feeding pulverized fuel to a furnace or other fuel consuming device, or to a plurality of fuel consuming devices, and the present invention more particularly relates to means of the character set forth in Letters Patent granted to me March. 8, 1921,N 1,370,872. In the invention disclosed in the above reas well as in the present invention, ll employ means designed to supply a constant and uniform fuel supply to a single or to a plurality of fuel consuming devices; means for maintaining a uniform fuel density at each furnace or consuming device; and means for maintaining, at a point in the system, an excess of powdered fuel in suspension sufficient to saturate an air stream or fluid carrier passed through the fuel while in suspension.

The present invention includes certain. modified forms of means for accomplishing the ends abovespecified, and, further, includes means for preventing clogging of the system and means for treating the air or fluid carrier before it is introduced to the system.

In the accompanying drawings, which illustrate applications of my invention,

Fig. 1 1s a diagrammatic elevational view of a powdered fuel system embodying my invention and showing in section a portlon of a fuel consuming device;

Fig. 2 is a View similar to Fig. 1 showing the air admission means arranged at a different point in the system; A

Fig. 3, an enlarged detail view partly in section and partly in elevation particularly showing the means for introducing the fuel to the closed circuit;

Fig. 4, a vertical sectional view taken on line fr-4C of Fig. 3; and

Fig. 5. a view similar tine 5--5 of Fig. 3.

Referring to the drawings, 1 designates a bin designed to contain the powdered fuel to be introduced to the system, said fuel beto Fig. 4 taken on Specification of Letters Patent.

Patented Apr. ilil, 1922..

191a. Serial no. 229,633.

ing supplied to the bin through a pipe 2 connected with the pulveriz'ing apparatus,

not shown.

As shown by Figs. 1 and 2, my invention contemplates supplying one or more fuel consuming devices with fuel carried thereto by a constantly circulating fluid stream, and while the drawings (Fig. 1) show only a single fuel consuming device 3, a plurality of furnaces or devices designed to be connected with the main feed pipe 4 by branches 5 may be employed. The branches 5 are each provided with a valve 5 adapted to control the passage of the fuel therethrough.

The circulation of the fluid stream and the fuel carried thereby is effected by a fan or blower of any suitable type. In thedrawings, 6 indicates the fan. In the form of Fig. 1, the return pipe 7 communicates with the inlet side of the fan 6 through a fuel feed measuring and mixing structure 8, an

outlet therefrom and a pipe connection 10.

In the construction of Fig. 2, the return pipe 7 leads directly to the inlet side of the fan or into the connection 10 beyond the structure 8.

The construction of Fig. 1 further differs from that of Fig. 2 in that the former admits air to the system at a point in the return pipe in advance of the fuel admitting and mixing structure'8, while the latter form admits the air at a point adjacent to the structure 8 and not directly into the return p1pe.

For the purpose of providing for and maintaining a constant circulation of a fluid carrier and the fuel carried thereby in the forms shown by Figs. 1 and 2, 1 form a closed circuit including, as illustrated, pipe 4:, return pipe 7, structure 8, fan structure 6, and connections between the structure 8 and fan 6. Air or other fuel carrier to take the place of that fed to the fuel consuming device or devices -is automatically introduced into the closed circuit at any convenient point beyond the fuel consuming devices and for the purpose of introducing this air or other fluid, I employ an inwardly operable valve 11 designed to be operated by the partial vacuum created in the closed circuit due to the discharge therefrom of the fluid and fuel. This valve 11 may be located as shown in Fig. 1, or it may be located as in Fig. 2, or at some other point in the system.

Prior to the introduction of the fluid carwithin chamber 17 I rier, particularly where atmospheric air is employed as the carrier, I preferably dry the air by passing it through a cooling or refrigerating device 12.

' To successfully operate powdered fuel feeding systems of the class of the present invention, and to provide the desired uniform fuel density at a furnace or at each.

furnace throughout the system, I consider it essential to create and maintain at a point in the system an amount of powdered fuel in suspension of sufficient quantity to saturate a stream or fluid carrier passed through the suspended 'fuel. This is to be distinguished from the practice of passing or dropping a quantity of pulverized fuel into an air or other moving stream.

As the quantity of powdered fuel or fuel dust carried by an air stream is proportional to the square of the speed of the air stream, it will be evident that with a constant speed and an excess of powdered fuel maintained in suspension, the density of the fuel in the stream as it leaves the point where the fuel is introduced to the system will be constant. Further, the density of the fuel will remain uniform throughout the closed circuit regardless of the quantity of fuel taken from the stream while in transit, up to some point in the circuit Where additional air is introduced to replace the air utilized.

The means for introducing the fuel to the fluid carrier as illustrated, includes a casing 13 having an inlet nozzle 14 designed to be coupled with the bin 1 by a coupling member 15. Casing 13 has its interior divided into a rotor chamber 16, chamber 17, and a lowerchamber 18. Mounted within chamber 16 is a rotor 19 having pockets 20 and provide agitating means 21. Both the pocketed rotor and the agitating means are driven by a shaft 22, which latter is driven by a motor 23 and the intermediate gearing 24 and 25. 26 designates a baflie plate for preventing the feed of fuel directly from the fuel inlet to the interior of the casing. Bafiie plate 26 is carried by an end cover member 27 adapted to be secured to the casing 13 byany suitable .means. Said cover is also provided with a nozzle 28 adapted, in the form of Fig. 1, to be connected with the inner end of the return pipe The agitating chamber 17 which is preferably of considerable area communicates with an outlet nozzle 29 formed on an end cover member 30,, and said nozzle is in communication with the inlet side of the fan 6 by means of pipe 10.

Chamber 17 having its positively driven agitating means 21, provides simple and eflicient means for maintaining an excess. of fuel in suspension. The fluid ,ca'rrier pass ing through this chamber becomes saturated an excess p pe connection between In order to prevent an -undesirable ac-' cumulation of fuel in the interior of the casing 13, I provide means for carrying the surplus fuel from the chamber 18 to the bin 1. These means, as illustrated, include a pivotally mounted plate or shelf 31 having a shaft 32; a counterbalanced arm 33 being secured to and rotatable with the shaft, said arm carrying a weight 34. Weighted arm 33 functions to first maintain shelf 31 in position to catch the surplus fuel and then, when moved, due to the weight of the fuel overbalancing the weight 34, to actuate a valve mechanism. These means are designed, after a predetermined load has accumulated on the shelf, to automatically operate a valve structure 35 which latter controls the passage of air under pressure through pipe 36. The air may be supplied from any suitable source, not shown, and is introduced to chamber 18 as particularly shown by Fig. 3. This air, or other fluid, meeting the surplus fuel in chamber 18, carries said fuel through pipe 37 up to and into the bin 1. 38 designates a turn buckle construction connecting the weighted arm 33 and the valve operating lever.

What I claim is 1. In a system for feeding pulverized fuel to one or more furnaces, the combination with a furnace branch pipe and a fuel supply bin, of a closed conveyor circuit in which a continuously circulating stream is maintained, said closed circuit provided with a blower, a pipe connection from the ..blower to the branch pipe, 9. return pipeconnection from the branch pipe in communication with the blower, and a fuel supply device having means for maintaining an excess quantity of fuel in suspension; means associated and cooperating with the fuel supplying device for passing a surplus of fuel from said device to the supply bin, and means for admitting fuel free fluid to that portion of the stream flowing from the branch pipe toward the blower.

2. In a system for feeding pulverized fuel to one or more furnaces, the combination with a furnace branch pipe and a fuel supply b1n, of a closed conveyor circuit in which a continuously circulating stream is maintained, said closed circuit including a blower, a pipe connection from the blower to the branch pipe, a return pipe connection from the branch pipe to the blower, a fuel supplylng devicehaving means for'maintaining quantity of fuel in suspension, a

the supplying device and the return pipe;

means associated emme I Q and cooperating with the fuel supplying desuspension therein, and automatically opervice for passing a surplus of fuel from said. able means associated with the fuel supplydevice to the supply bin, and means for passing device for passinga surplus of fuel from ing fuel free fluid to the supplying device the supplying device to the fuel supply bin,

5 and through the fuel suspended therein. In testimony whereof I afi'ix my signature 15 3. In a system for feeding pulverized fuel, in presence of two Witnesses. the combination with a fuel supply bin and WALTER O. AMSLER. a closed conveyor circuit including a fuel. 7 Witnesses: supply device, said device having means for J. M. GEOGHEGAN,

'1-0 maintaining an excess quantity of fuel in Low WINEMAN.

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