Apparatus for producing gas

Aug. 8, 1939.

JU. MCDONALD

2,168,652

APPARATUS FOR PRODUCING GAS

Filed July 9, 1937

<img file="US2168652A_D0001.tif" />

<img file="US2168652A_D0002.tif" />

<img file="US2168652A_D0003.tif" />

Patented Aug. 8, 1939

2,168,652

UNITED STATES PATENT OFFICE

2,168,652 APPARATUS FOR PRODUCING GAS John U. McDonald, Clinton, Mo.

Application July 9, 1937, Serial No. 152,726

Claims.

This invention relates to an apparatus for producing gas from various materials as desired such as from any kind of carbonaceous material, solid or liquid, including vegetable and S animal matter, including any of the various types of coals, peat, saw-mill refuse, wood, garbage, and oil.

It is a primary object of this invention to provide an apparatus for the production of a 10 clean, fixed and permanent gas to have a high calorific value, in a steady, rapid, and continuous operation with a complete gasification of all of the combustible constituents as well as of the moisture and tarry substances of the fuel acted W upon so as to leave nothing but an ash con. tent as a residue.

It is a further object of this invention to provide apparatus which will heat the gas producing material in such a manner that the steam and 20 gases produced are retained and forced down through a bed of incandescent carbon so as to crack the volatile constituents to a fixed permanent gas. A still further important object of the invention is to remove the ash residue from the 25 generating chamber and also to remove the flyash from the gas and then wash and condense the gas without causing a precipitation of some of the constituents thereof.

Reference is made to my co-pending process 30 application, Serial Number 152,725, as filed in the United States Patent Office July 9, 1937.

These and other objects and advantages of the invention will become apparent to those versed in the art in the following description 35 of one particular form of the invention which is more or less diagrammatically illustrated in the accompanying drawing in which—

Fig. 1 is a diagram in side elevation and partial section of the apparatus embodying the in40 vention, and

Fig. 2, a transverse horizontal section on the line 2·—2 through the generator in Fig. 1.

Like characters of reference indicate like parts , in the two views in the drawing.

A generator generally designated by thehu-. meral 10 is formed to have a lower inverted frusto-conical section II, the outer wall of which may be made of steel and lined sufficiently with a suitable refractory wall 12. On the upper end of this lower section II is fitted in a gas tight manner a cylindrical mid section 13 likewise lined with a refractory material. On the upper end of the mid section 13 is fitted in gas tight relation the conical section 14 which carries a head ' 55 15 on its upper end.

(Cl. 48—76)

This head 15 has a side entering pipe 16 which is provided to conduct the fuel into the generator by any suitable means such as by the screw conveyor 17 as herein indicated. The head 15 is further provided with a cap or valve 18 of the g quick-detachable nature, ordinarily held in a closed sealed position by means of the screw shaft 19 carried through the bar 20' supported above the head 15. In order to prevent loss of gas from the generator 10 on admitting fuel through the ]0 pipe 16, any suitable means for feeding the fuel without escape of gas may be employed, such as by employing a fuel hopper 20 through the lower portion of which passes the screw conveyor 17, the drive shaft 21 of the conveyor^u being IS carried through a suitable packing gland 22 externally of the hopper. The fuel hopper may be loaded with the desired fuel through its top which is normally closed by the quickly detachable valve or cover plate 23. The fuel hopper may be made 20 of such depth and capacity as will permit a sufficient amount of fuel being carried therein as will prevent any material escape of gas upwardly therethrough when additional fuel is being added to the hopper. 25

The lower end of the generator section 11 opens into a receiving chamber 24 which is here shown · as having a horizontally disposed floor 2S through which vertically extends a shaft 26 in gas tight manner. It is understood that the chamber 24 30 is fitted to the open end of the generator section I I in a gas tight manner.

Placed centrally within the lower end of the generator section II is a conical grate 27 which is provided with slots 28 therearound through 35 which the residue ash may fall. The larger particles of the residue which may not pass through these slot openings 28 may travel down the inclined face of the grate 27 to be engaged by projections 29' extending outwardly from the 40 lower pgrtioh of the grate so that as the grate 21 may be revolved, these larger particles will be ^:ground up or at least reduced in size sufficiently as will permit them to fall through the annular opening left around the lower end of the grate 4s and the throat or opening end of the generating section II. In order to resist wear under this grinding action the throat of the section II is preferably provided with a metal ring 38, here shown as extending in the upper portion of the M chamber 24. The shaft 26 may be revolved in any suitable manner such as through a drive shaft 31, a worm 32 and a worm wheel 33 mounted on the shaft 26.

The generator mid section 13 carries a conduit 85

2,168,652 or pipe 34 diametrically thereacross to have the conduit extend outwardly therefrom by its ends. This pipe 34, in the form herein shown, is provided with a surrounding jacket 35 through which ₆ water may be circulated for the purpose of keeping the pipe 34 cooled to within working limits and to prevent distortion thereof by undue heating. In the form herein shown, the jacket 35 is provided with a water inlet connection 36 10 and a water discharge pipe 37.

The pipe 34 is provided with a central upwardly directed discharge jet or nozzle 38 opening into the generator within the mid section i 3. The pipe 34 is provided with suitable fittings 15 on its outer ends for the selective admission of air, oil, or steam.

In placing the generator in operation, fuel is admitted to the generator and ignited in any suitable manner such as by dropping incandescent 20 coals therein. Air may be initially supplied through the upper pipe 39 in the head 15 . and the lower ports 40 in the lower section 11, it being understood that the pipe 39 and the ports 40 are normally closed after the initial starting of the 25 operation. Fuel is added to the generator to completely fill it up to the head 15 and combustion is maintained after being initiated by air escaping through the jet 38 into the central portion of the fuel within the mid section 13. 30 The combustion zone then extends from slightly above the grate 27 to a short distance above the jet 38 within the midsection 13 with the raw fuel thereabove and being heated thereby.

Thus, by burning part of the fuel, the upper 35 portion is initially heated to drive out first the more volatile portions which set up a slight pressure tending to drive the gas produced downwardly and out through the lower throat of the generator to the chamber 24. Tars and other liquids 40 driven off by the heat pass downwardly through the incandescent zone and are thereby converted into a fixed and permanent gas. Also by admitting the air centrally into the combustion zone, all the oxygen is used up in that zone and 45 hence the gas is not subject to oxidation or burning by that air. The residue as above indicated is in the form of an ash which likewise is dropped into the chamber 24. Hie pressure of the gas in the generator carries the gas through the slots 50 21 in the grate and thereby carries out the accumulation of fine dust. IMs residue is removed from the chamber 24 by means of a vane 41 which hangs downwardly from the grate 27 so as to scrape the ash around to drop into the discharge 55 Pipe 42. Both the ash and the gases from the generator travel outwardly through this pipe 42 ) into the ash receptacle 43 which is sufficiently large to receive and retain the ash over a rather long period of operation before the receptacle oo has to be cleaned. The ash may be removed through the lower valve 44'. The incoming residue is directed toward the bottom of the receptacle by the slope of the pipe 42. Gas is conducted from the receptacle 43 by the pipe 44 leading 65 from near the top of the receptacle 43 into the lower end &lt;?f the gas washer. This gas entering the washer 45 will convey with it some fly-ash. This material is removed from the gas in the washer 45 by water discharged from the pipe 49 70 through a central hole 47 provided in the upper cover 41 of the washer.

Within the washer 45 is a. lower Inverted cone 49 secured by its upper end in substantially gas tight relation around the inner side of the wall 75 of the washer. The lower end or apex of the cone 49 is provided with an opening through which the gas coming from the pipe 44 may escape upwardly. Above the inverted cone 49 is mounted a cone 50 which has its lower end spaced inwardly from the wall of the washer a sufficient distance 5 to leave a rather narrow annular opening therearound.

As the water comes through the opening 47, it drops onto the apex of the cone 59 and thus flows down in a continuous sheet over the entire surface 10 of the cone 50 to discharge through the annular opening about its base into the cone 49 to flow in a more or less continuous sheet thereover and discharge from the lower opening into the bottom of the washer. Thus, it is to be seen that the wa- 15 ter is flowing downwardly against the upwardly rising gas over the same path that the gas must travel to escape.

The discharge water from the washer flows through the pipe 51 into the trap 52 and out the 20 discharge 53. As indicated by the drawing, the discharge 53 is provided at a sufficient elevation above the lower end of the entering pipe 51 to form a seal so as to prevent the escape of gas.

From the washer 45, the gas flows through the 25 opening 47 into a receiving chamber 54 from which the gas is conducted .through the pipe 55 to the upper end of a. condenser 56 which is herein shown as being mounted directly above the washer. In this condenser the gas enters a re- 30 ceiving chamber 57 from which the gas may flow downwardly through a plurality of tubes 55 into a cooling chamber 59 from which the gas may be taken for the use desired. The condenser is formed to have the tubes 51 surrounded by wa- 35 ter which enters from a water inlet pipe 60 to flow upwardly around the tubes 53 and then discharge through the' pipe 46 into the washer. Since,the gas coming from the generator II is carrying volatile matter that might otherwise be 40 condensed by sudden chilling, the water entering the washer 45 is pre-heated by being initially parried through the condenser as above indicated so that the temperature of the gas is not suddenly reduced by being brought into contact with cool 45 water. By conducting the gas through the washer and the condenser with the water flow as indicated, there is no precipitation produced and the gas thereby retains all of its constituents in the gasified state although eventually reduced In tem- 50 perature.

It is thus to be seen that the generator II may be operated in a continuous manner without interruptions for the admission of fuel. It is also to be seen that the travel of the volatile matter 55 and gases produced is always downwardly through the incandescent fiiel bed and that the incandescent zone is maintained and limited by the transversely extending pipe 34 and its single central jet 38. This pipe further serves as a means eo for admitting steam and oil to secure the proper calorific values. It is further to be noted that in the form herein shown and described, no water seals are required. In further reference to the introduction of the air in the central part of the 65 mid section 13, this mode of introduction provides for the uniform combustion of the fuel through the central portion and prevents the heretofore occasioned difficulty of by-passes being formed through the fuel bed when the air was 70 introduced from above or a vacuum applied at the base of the generator.

While I have herein shown and described my InVention in the one particular form, it is obvious that structural variations may be employed 75

2,168,682 3 without departing from the spirit of the invention, such as varying the position of the air discharge jet 38 from the vertical center to any suitable workable position intermediate the top and bot_s tom of the. generator, and I therefore do not desire to be limited to that precise form beyond the limitations as may be imposed by the following claims.