US1167149A - Method of treating coal-gas. - Google Patents

Description

H. A. CARPENTER.

METHOD OF TREATING'COAL GAS.

APPLICATION FILED MAY 6, 19M

Patented Jan. 4, 1916.

2 SHEETSSHEET l- INVENTOR H. A. CARPENTER.

METHOD OF TREATING COAL GAS.

APPLICATION mm WW6, 1914.

1,167,149. Paim'ated Jim. 4, i916.

2 SHEETS SHEET 2 UNITED STATES PATENT OFFICE.

HENRY A. CARPENTER, OF SEWICKLEY, PENNSYLVANIA, .ASSIGNOR TO RITEB-CONLEY MANUFACTURING COMPANY. OF PITTSBURGH PENNSYLVANIA, A CORPORATION OF NEW JERSEY.

METHOD OF TREATIN E- GOAL-GAS.

Application filed May 6, 1914.

T 0 all whom it may concern Be it known that I, HENRY A. Gnarnx 'rnR a citizen of the United, States, residing at Sewickley. in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Methods of Treating Coal-Gas, of whichthe following is a specification.

One object of this invention is to provide for the removal of the heavier hydrocar bons, such as tar and naphthalene, from coal gas immediately upon discharging the product of gas generating retorts from the stand"- pipes and before these substances have had opportunity to pass to the take-oil main and to the apparatus beyond, thereby eliminating most of the stoppages heretofore experienced and at the same time decreasing the work of those portions of the apparatus or system to which the gas is delivered from the main.

A further feature and object is to accomplish this separation after the gaseous flu d has attained such temperature as results in fixing some of the lighter and enriching hydrocarbons into a permanent gaseous state which in the absence ofsuch temperature would condense and be carried away with the tar. Approximatel 1000 F. is an ethcient temperature for fixing the lighter hvdrocarbons into a permanent gaseous state, although it may be higher, and even lower temperatures may sullice.

In order that the quality of the gas delivered'to the take-oil main may be substantially uniform. the gaseous fluid discharging -from .t-he stand-pipe should be maintained at "Ia. r-'i ilati\el v constant temperature. and till.- .e accomplished by alloting a proper nmnber of retorts to each stand-pipe and bvso alternating or arranging the retort charging periods that the resultant of the low temperature of the product of freshly char-gird retorts and the maximum temperature ol the product of other rctorls will be an ellicient lifting tenuicrature. 'lhe requisite high temperature having been attained and the lighter lrvdrocarbmis thereby iixed into permanent gaseous state beforpv (llS- chargingfromthe stand-pipe. reduction of the temperature of the gaseous fluid im 'i'nediately upon issuing from the stand-pipe is of prime importance t9 avoid the accumulation of solid deposits 1n the take-otlmeans lhe temperature should be reduced to from Specification of Letters Patent.

Patented Jan. 4, 1916.

Serial No. 836,677.

110 to 125 F. for the best results, and it therefore becomes a further object of the invention to interpose means between the standpipes and the take-off main for accomplisl'iing this immediate temperature reduction. The apparatus is constructed to provide ready access to the stand-pipes for clearing them of stoppages, and provision is also had for disposing of the precipitated tar and other hydrocarbons, keeping the latter clear of the stand-pipes and of course preventing them from gaining access to the take-oil. The net result is that enriched and relatively clean gas passes to the apparatus beyond, thereby minimizing such ap paratus, and otherwise reducing the expense incident to the treatment of foul gas which, under present practices, is delivered to the system through the hydraulic main.

\Vhile the present invention does not accomplish the removal of all naphthalene, only a small percentage is carried forward. This is due to the fact that full saturation of the gas at 110 F. is accomplished by a small amount of naphthalene, whereas at higher temperatures, the absorption is proportionately greater. Heretofore, due to the relatively high temperature at which the enters the system much naphthalene carried forward and is subsequently thrown down at points where no tar is to absorb it, causing serious stop- A further advantageous result is a relatively large number of retorts may boqconnected to one stand-pipe, as here shown the benches being eight-high, so that a single pipe handles the product of sixteen retorts. ,This results in economy in space and in The cost of constructing the benches. It may'bepossible tolincrease the number of retorts for each stand-pipe, but even an eight-high construction is a substantial advance over present practice.

In the :u-rompanying drawings, which are large diagranunatic.., Figure 1 is a front elevation of apparatus for practising the invention; Fig. 2 is a iew in top plan of the same; Fig. is an end view; and Fig. 4. is a view in cross section of one of the cooling chambers or receivers inter- 105 designates the front of a bench. and 3 are retorts of 110 usual construction arranged one above the other, in the present adaptation, the retorts being arranged in tiers of eight high and with a stand-pipe 4 connected to the retorts of two adjacent tiers, and thereby taking care of the product of sixteen retorts.

5 designates the take-ofi' main which is connected at 6 to the twin exhausters -T which may be utilized alternately, in accordance with present. practice, for' deliye'ring the gas to scrubbers or other portions of the apparatus beyond, not shown.

Interposed between the take-ofi' main 5 i and the stand-pipes4 are the cooling chambers or receivers 8 into 'which the stand pipes discharge, as clearly shown in Fig. 4.-

In the preferred construction, the bottom 9 jof each chamber is inclined to form the trough or valley, 10, with the stand-pipes 4 projecting through and above the inclined bottom to exclude the liquid accumulation in the trough. At the top of chamber 8 are valves 11 for closing openings l1','thelatter.

being'in line vertically with the stand-pipes for the introduction of pipe cleaning devices or for gaining access to the .stand-.

pipes for any other purpose.

The cooling means for each chamber 8 consists of a suitable number of liquid Sprayers 12 depending thereinto from the chamber top and arrangedout of vertical line with the stand-pipes to minimize the amount of liquid entering the latter. A closed circulating system is preferably employed, for which no novelty per se is claimed herein, as thereby much ammonia is saved as compared with a fresh water circulation for the reason that after the a cooling medium has become saturated, no additional ammonia is extratcted from the gaseous fluid being treated. The circulation system includes a drain 13 for conducting the tar and cooling liquor from trough 10 to a conventional form of tar separator 14, the tar discharging from the with the product thereof at maximum temperature.. And the manipulation is preferably such that the gaseous product discharges from the stand-pipe at approximately 1000 Egffjfand as heretofore explained, this tempefature results in fixing into permanent gaseous state the lighter hydrocarbons, there- 'y materially enriching the ultimate cleansed gas, retaining in the latter valuable products w h1ch, d ue to the absence of a sufiiciently hlgh fixlng temperature, have heretofore been dissociated from the mafn body of gas and virtually lost. Immediate cooling of the stand-pipe output is necessary toprevent accumulation of solids in the take-ofi' main and apparatus beyond, and this is accomplished by the liquid sprays which the gaseous fluid encounters immediately upon emerging from the stand-pipes, the operation being preferably such that its temperature is reduced to from 110 to 125 F. This temperature reduction results in precipitating the major portion of the tar and also nearly all of the naphthalene, the latter combining with the tar, and the condensates and the cooling liquid draining into trough 10 and discharging to separator 14 through outlet 13, as above explained. Chambers 8 are designed with special reference to accomplishing the described cooling operation with maximum efliciency, and also for the purpose of obtaining a proper withdrawal therefrom of the cleansed and cooled gas. \Vith these considerations in view, relatively short chambers are employed, as thereby the cooling and withdrawing of the gas may be more effectually controlled and greater uniformity attained than though a single continuous chamber for all the benches were provided. In practice, each chamber is preferably arranged to accommodate three stand-pipes, and with such arrangement, no difiiculty has been experienced in maintaining the desired highly eflicient conditions above described.

And this arrangement provides for more accurately controlling the withdrawal of the cleansed and cooled gas through the valved outlets '21 to the take-ofi' main 5, the valves of these connections being so adjusted as to subject all of the cooled and cleansed gas to uniform exit force with the result that no portion of the gas is retained within the chamber for. an appreciably longer period than any other portion thereof.

What I claim is .1. The method herein described of treatmg coal gas consisting in maintaining a stream of gas within a stand-pipe at a gas- 115 fixing temperature, discharging the stream from the stand-pipe immediately into a gas container and subjecting the gas within the container to a substantially uniform temperature reduction, and withdrawing the re- .duced temperature gas from the container.

2. The method herein described of treatmg coal gas consisting in discharging gas" from a plurality of retorts into a stand-pipe .and thereby producing a continuous stream of gas in the pipe, maintaining such stream at a substantiallyuniform gas-fixing temperature, discharging the high temperature stream from the stand-pipe immediately into a gas contamer and subjecting the gas within the oontainer'to a Substantially uniform temcontainer to a Substantially uniform .tem-

perat ure. reduction and thereby removing imperature reduction, and subjecting the cooled purities therefrOm,-and withdrawing the and cleansed gas within said feoi tainer to .qpurified 'reducedl-temperature 'gas from the exit force that acts equally on a-llpbrtions of; 1 5' container, 1 thegas, I I

3; The method herein described ofvtreat- In testimony wh e "Q'f I aflix my signature-5;.

ing coal gasgepn'sistging. i nf maintaining n inpresence of two witnesses.

streem'ofgas' fa'stand-pipexat a gas-'- HENBY'-{A :OARPENTER.; temperature, the stream Witnesses: 10 from the stai1d -pi-pe. 'immedmte y into. a'gas .J. M. NEsBrr, Y

'- container and "subjecting the-gas within the F. E. GAITHER.

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