US 1055334 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
W. G. LAIRD.
PROCESS OF MAKING GAS.
APPLICATION IILED AUG. 23, 1911.
1,055,334; 1 Patented Mar. 11, 1913.
3 SHEETS-SHEET 1.
WITNESSES}. 4/424 & 1M4 uwmron 1 p 1 BY gum/7 r 7I/d4E/( 7 /8 ATTORNEYS W. G. LAIRD.
PROCESS OF MAKING GAS.
APPLICATION IILBD AUG. 23, 1911.
1,055,334. Patented Mar. 11, 1913.
M 3 SHEETS-SHEET 2.
G F FIG. 2
W. G. LAIRD.
Pnocsss or MAKING GAS, APPLICATION IILBD AUG. 23, 1911,
Patented M 11'. 11, i913.
3 BHEETB-BKEET 3.
J2 D A; 3 4,
WITH/E8858. INVENTOR his wzromvsrs UNITED STATES rrnnr OFFICE.
WILBUR G. LAIRD, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR TO TH E IMPROVED EQUIPMENT COMPANY, OF NEW YORK, N. Y., A CORPORATION OF COLORADO.
PROCESS OF MAKING GAS.
Specification of Letters Patent. Patented luau 11, 1913,
Application filed August 23, 1911. Serial No. 645.558.
To all whom it may concern:
Be it known that I, WILBUR G. LAIRD, acitizen of the United States, and a resident of Washington, District of Columbia, have invented certain new and useful Improvements in Processes of Making Gas, of which the following is a specification.
The invention relates particularly to processes of producing gas by the distillationof coal and similarly distillable carbonaceous material.
In its most preferred and complete form, the objects of the invention are to produce by distillation from coal, peat, oil, wood or similar carbonaceous material or a combination of two or more such materials, a large yield of gas of a rich nature and of high light and heat-giving quality, and to accomplishthis with a small amount of fuel used .in supplying heat in the process and a small amount of labor and expense. These objects are carried out by the process in its most preferred form, in a manner to heat the material to be distilled very uniformly while in a finely divided and distributed condition, to a suitable temperature for distillation and fixation, and to maintain a small temperature range above the theoretical minimum, by such an even distribution and application of heat to all portions of the material undergoing treatment, that the I maximum temperature reached by any of the distilled products shall be insufiicient to break up the gases to any great extent, into compounds of lower order or less heat and light-giving power. a
The very even distribution of heat and of the fine material is effected by imparting to the material a spiral, whirling or centrifugal motion during its fall through the heated retort by injecting heated gas at several points into the stream of falling material whereby a regulated path of travel is insured, and the particles very uniformly acted upon and heated by their near approach to the' heated walls of the retort caused by the centrifugal eflect.
In the most preferred embodiment of the invention, solid material to bedistilled, is ground or otherwise reduced to a small granular condition and mechanically fed into a heated carbonizing chamber through which it falls by gravity through a vertical distance which may, for example, be twenty or thirty feet. If Oll, instead of solid material, is used, it is sprayed into the upper end of the distillation chamber. In the chamber the finely divided material is acted upon transversely by jetsof gases injected tangentially to the inner periphery of the chamber with sufficient velocity to produce a whirling motion of the 'falling p==rticles. This whirling motion, through centrifugal force causes the particles to be thrown away from the axis of the vortex and close to the heated walls of the retort chamber where they become heated by radiation from the walls and by coming in contact with currents of heated non-oxidizing gas whereby they are subjected to a temperature sufficient for distillation and the fixation of the evolved gases to the extent required. For example, with Westmoreland coal, a temperature of eleven hundred degrees F. for the outgoing gas and also for the in'ected gas is suitable for a high yield of fixe gas with good light and heat-giving power. With any particular carbonaceous material selected the best practice is to regulate the heat of the chamber and rate of feeding the material with regard to the temperature of the out-going gases and to select and maintain the temperature at which the gases prove to be best suited to the various requirements of yield, candle power or calorific power; the current commercial values of the by-products and residuals being also considered.
Inasmuch as all portions of the evolved gases are subjected to very nearly even conditions of time and temperature by theprocess there will be a substantial uniformity in the products produced. Each portion will have been subjected to substantially the same temperatures and no port-ion will have been heated materially in excess of the rest, avoiding the danger that part of the products evolved will reach too low a maximum v temperature to give adequate yield of fixed gas while simultaneouslyv other parts are too highly heated to give sufliciently rich gas,
both of which results may occur where large massesof .earlminu-eons material are heated rapidly and not evenly in a body by contact or radiation and \vhere'the evolved products are not i|nil'orinl heated.
Preferably (are is taken to admit as little air as possible with the material to be distilled. Preferably also gas heated to the temperature of thatleaving is forced into the chamber in jets tangentially directed either horizontally or slightly upward along the chamber walls so as to give a whirling or vortex motion to the falling material and the gaseous contents increasing the length of the path of travel of the particles, imparting centrifugal force and producing uniformity of action. The entering gases may be more or less inclined upward to delay or retard the falling velocity of the particles.
At the axis of the vortex the evolved products are edncted through a central offtake pipe. This location of the off-take tends by reason of the vortical and centrifugal effect to prevent the solid residuals from entering such elf-take with the evolved products. These solid residuals which in the case of a coking coal will be small particles of coke fall finally to the bottom of the chamber where they collect and are withdrawn at intervals or continuously.
Preferably the heating of the walls of the retort chamber is effected by means of a surrounding combustion chamber in which gas (for example producer gas) is burned to supply the heat. The temperature of the retort chamber walls in order to rapidly impart heat should preferably be considerably higher than that reached by the falling particles or by either the gases evolved or the gases forced into the retort chamber to cause the vortical motion. The injected gases may be drawn from the off-take pipe leading from the retort chamber and blown directly back into it by means of suitable fans or blowers.
It will be seen that by reason of the distribution of the material in this process into finely divided grains or particles separated and falling through a heated chamber the heat very quickly reaches all portions. Gas coal is a verypoor conductor ofheat and the time and differential temperature necessary for the heat to penetrate to the center of each mass is greatly lessened by finely dividing the coal and exposing the surfaces of the particles to. the application of heat separately in a cloud or shower as described. Coal offers a surface favorable for the absorption of radiated heat. The whirling motion produced by the tangentially entering gases maintains the particles by centrifugal force in .close proximity to the heated retort walls. The gases driven along the walls of the retort also absorb heat from the hotwalls and thus form a heat carrying medium through which the material is distributed thereby greatly aiding the 'application of heatas well as producing a localized stirring action close to the heated walls which substantially prevents the formation of bodies of superheated gases and insures a substantial uniformity of temperature distribution at each stage of progress of the material through the retort.
Preferably the retort chamber is vertical and of uniform circular cross section from the top to the gas-educting month.
In the accompanying drawings one simple form of apparatus suitable for carrying out the process is illustrated.
In these drawings, Figure 1 shows a side elevation partly in central section of such apparatus. Fig. 2 shows an exterior side elevation from the right hand side of Fig.
1. Fig. 3 shows a sectional plan view of Fig. 1, the section being taken on line WXYZ as shown.
The form of apparatus shown and which is suitable for carrying out the process herein described, consists of a vertical retort chamber A, composed of any suitable material such as fire clay, surrounded by a combustion chamber B, suitably equipped with checker brick B Surrounding the combustion chamber B is the outside wall B At the bottom of the combustion chamber B is the fine or conduit H, which opens into the combustion chamber B, through the openings H This flue H, isequipped with pipes J and valves J for supplying the suitable combustible gas to the combustion chamber. At the top of the combustion chamber B, is the flue L, which opens into the stack or chimney M. At the top of the retort chamber A, is arranged the feeder 0, containing the fixed apron C and the revolving cone C driven by the spindle C attached to the gear C, which is driven by the pinion C Passing through the outside wall B and the combustion chamber B', and entering the retort chamber A, tangentially to its inner periphery are the pipes A terminating in the very narrow twyer openings A for giving high velocity to the gases as they lssue into the retort chamber A. These pipes A v are equipped with valves A and connect with the pipe lines A and A which lead from a blower N which has its inlet connected through the pipe N from the discharge line F the retort chamber A and substantially on its central vertical axis is the gas off-take pipe D terminating at its upper end in a hood orcover D which leaves an annular Extending through the bottom of open space D beneath it for the entrance of the gases into the off-take pipe D. This .ofi-
- take ipe D is connected by means of the' pipe 3 to the tar extractor or cleanser E which is connected by the pipe E to the exhauster F discharging through the pipe 1 to an other cleansing apparatus or storage cham )er as may be required. At the base of the off-take pipe D is the extension pot orsump D for the collection of small particles of solid material or tarry matter which may 7 enter the off-take with the entering gases. At the lower end of the retort A are the inclined openings G terminating in the doors; G which ermit the removal of the solid residuals. he air inlets K leading into the T combustion chamber B are equipped with suitable dampers K which are for the pur pose of admitting the necessary air for combustion in the combustion chamber.
The process is carried out in the form of apparatus shown as follows: Combustible gas is admitted to the combustion chamber B through the pipes J, the flue H and the openings H and controlled by valves J 2 and suflicient air for combustion, secondary air, is admitted through the dampers K and the openings K to produce combustion within the chamber B and heat the retort A to the required temperature. The gases risin in the combustion chamber B are deflecte by the checker brick B and finally reach the flue L from which they are conducted to the stack or chimney M and thence to waste. It will be understood that by a proper adjustment of the valves J and dampers K the rate of combustion in the combustion chamber B and consequently the temperature of the retort A can be easily regulated.
The feeder C is filled with the material to be distilled for example coal which has previously been reduced to a granular condition. By means of the revolving pinion C which drives the gear C* the spindle C and the cone C the fine coal is fed through the annular opening G into the retort chamber A in a uniform and continuous stream close to and entirely around its inner periphery. The coal particlestend by the force of gravity to fall directly to the bottom of the retort ghamber A. By means of the blower N, however, a portion of the gases passing throu h the pipe F are conducted by the pipe 1 to the blower N and discharged through the pipes A, A, valves A and pipes A and into the retort A through the narrow openings A at high velocity imparting to the falling coal particles and gaseous medium a lateral motion along the wall of the retort and resulting in giving a rapid whirling or vortical motion to the entire contents of the retort except at the bottom where the residuals collect. The solid residuals are withdrawn through the openings G and the doors G at intervals and the gases pass out through the off-take opening D the heated walls of the retort facilitating 1 their being quickly and uniformly heated by the gases and by radiation from the walls before their final deposit at the bottom of the retort. The centrifugal action which controls their path of travel also prevents.
them from entering the off-take pi e which is located on substantially the axis of the 1 vortical movement. The injected gases are conveniently composed of a portion of those distilled within the retort and they are preferably introduced at a temperature substantially the same as those leaving at the offtake and any heat loss caused in the course of their return may be restored to them during their passage through the pipes A which may be of thin material and consequently heated by the hot gases in the combustion chamber B through which they pass. These hot injected gases mingling with the heated products evolved from the coal particles form a heated gaseous medium in which the coal particles are distributed in a cloud or shower of separated particles with a very large aggregate exposed surface for the reception and absorption of heat radiated from the hot walls of the retort and also for the absorption of heat by direct contact with the heated gaseous medium surrounding them.
Through the vortical motion produced, the injected gases are also very uniformly stirred with the evolved gases and this results in a more even distribution of temperature throughout the gaseous medium in any one horizontal zone or plane than would otherwise occur. The ases themselves in their movement along t e interior hot surface of the retort are heated by contact therewith thus acting as a heat conveying medium for the transfer of heat from the retort walls to those coal articles which may be more remote from tie retort walls and therefore less heated by radiation therefrom.
It is obvious that in carrying out the process the form of apparatus used is capable of wide variation. For example the retort may be heated in any suitable manner and may be arranged at any suitable form. The material to be distilled may be introduced in other ways. Any suitable means may be employed for the removal of'the deposited solids.
The injected gases may be composed of a x trifugal force produced and educting the &
portion of the gases distilled within the retort or mayv be taken from any suitable source. The tar extractor or cleanser shown may or may not be employed and the injected gases may be secured from the educted gases without previous cleansing if desired.
I'am aware that it has been proposed to inject pulverized coal into gas retorts with steam with the object of scattering the particles instantaneously over the heated interior of the retort and so causing the evolution of gas; my process on the contrary sub-- jects the particles to distillation while passing relatively slowly and through a relatively prolonged pathway between the heated walls of the retort and only the residual solids are designed to come to rest on the bottom of the retort.
Another more elaborate form of apparatus for carrying out my process is shown in my application #480,614, filed March 1, 1909. This present application is for the process as an invention separate and distinct from any particular apparatus.
I claim the following 1. Process of making gas by distillation comprising passing the gas making material between heated walls ina finely divided condition and while separated and distributed in a substantially non-oxidizing medium and distilling the material during such passage and regulating the motion of the material and said medium by imparting thereto a vortical motion by jets of heated gas directed along the heated walls transversely to the direction of passage.
2. Process of making gas by distillation comprising passing the gas making material between heated walls in a finely divided condition and while separated and distributed in a substantially non-oxidizing medium and distilling the material during such passage and regulating the temperature of said walls with respect to the length and time of passage to impart to the passlng material the desired temperature and aiding the application and distribution of the heat by introducing at successive points during the passage streams of hot gas.
3. Process of making gas by distillation comprising subjecting gas making material to radiant heat in a heated chamber in a finely divided state while distributed in a whirling and substantially non-oxidizing gaseous medium and separating the aseous products from the solid residuals by t e cengaseous products. 0
4. Process of making gas by distillation comprising passing the carbonaceous gas .maklng material between heated walls in a I finely divided state and distributed in a substantially non-oxidizing gaseous medium,-
and progressively raising the temperature of the material to a distillation temperature 5. Process of making gas comprising feeding finely divided gas making material in a stream between heated walls and making gas While in transit and while subjecting the material to a centrifugal action by introduc-' ing a gaseous stream transversely in a direction to set up a vortical motion.
"6. Process of making coal gas by distillation comprising subjecting distillable carbonaceous fuel in a finely divided state to radiant heat in a heated chamber while floating and slowly falling in a path sufliciently long for the substantial completion of the distillation and in a substantially non-oxidizing carbonaceous gaseous medium.
7. Process of making coalgas by distillation comprising subjecting distillable carbonaceous fuel in a finely divided state to radiant heat in a heated chamber While floating and slowly falling in a path sufiiciently long for the substantial completion of the distillation and in a substantially non-oxidizing carbonaceous gaseous medium and introducing jets of heated carbonaceous gas into said chamber transversely to the general progress of the said fuel therein.
8. Process of making coal gas by distillation comprising subjecting distillable carbonaceous fuel in a finely divided state to radiant heat in a heated chamber while floating and'slowly falling in a path sufliciently long for the substantial completion of the distillation and in a substantially non-oxidizing carbonaceous gaseous medium, and passing some of the heated gaseous medium 1n a closed circuit back into said chamber in a direction to stir and increase the length of paths of the fuel particles.
9. Process of making gas comprising passing distillable carbonaceous fuel in a finely divided floating or falling state through a heated chamber and subject-ing it therein to jets of gaseous fluid transverse to the direction of general progress of the fuel and thereby subjecting the fuel to radiant heat while so passing in a prolonged path .of progress.
10. Process of making gas comprising passing downward by gravitation finely divided fuel through a: hot chamber, and at intervals during its passage directing into it'transversely to its passage jets of gaseous fluid and thereby prolonging the paths of passage and inducing a circulation .of the falling fuel to and from the walls of the chamber.
11. Process of making gas by distillation comprising passing the carbonaceous gas making material between heated walls in a finely divided state and distributed in a substantially' non-oxidizing gaseous mediu and progressively raising the temperature 0 the material to a distillation temperature, In testimonywhereof I have signed this and injecting substantially non-oxidizing specification in the presence of two subscribgas into said medium transversely to its ing witnesses.
passage and substantially parallel with and WILBUR G. LAIRD. 5 along the heated walls whereby the medium Witnesses:
is brought into intimate contact with the K. G. LE ARD,
heated walls and absorbs heat therefrom. JOHN HERE.