US2315555A - Treatment of gas distribution systems - Google Patents

Description

TREATMENT OF GAS DISTRIBUTION SYSTEMS John R. Skeen, Philadelphia, Pa., assignor to The United Gas Improvement Company, a corporation of Pennsylvania Application July 22, 1939, Serial No. 285,942

6 Claims. (Cl. 48-190) Thls application is a continuation-inpart of my eopending application Serial Number 236,822, flled October 24, 1938, and pertains generally to the treetment of the interiors of gas mains or other gas enclosures with a lqud mixture containing a non-cyclic high bolling ali phatic alcohol and monophenyl ether of ethylene glycol.

Systems for the distribution of gas include conduits r mains which are usuaily laid underground, and which comprise sections of pipe Joined together by means of welding, by means of packed joints, by means of screw joints, or otherwise, I

'Ihe welded joint is a more recent development and is used chiefly to Jpn pipe sections of steel or ron, other than cast ron.

Older mains are usually made up of cast ron pipe sections joined by means of bel] and spigot or other similar joints. These joints are usually packeci with hemp, jute, flax or other cellulosic materie] which in turn is backed up with leed or cement or other material in a well known marmer.

Over a period of years the water condensed from wet gas together with other constituents of the gas such as carbon dioxide, hydrogen sulphide, hydrocyanic acid, naphthalene. and so forth, have in many nstances, caused extensive corroslon of the interior walls of the mains. The products of corrosion have accumulated on the walls of the mains and, in many instances, large quantities have become disconnected and have collected along the bottom.

Due to the presence of relatively large quanti tes of moisture, largely responsible for the corroson in the first instance, the products of corrosion Ware maintained in 21 Wet condition and dd hot: tend to form dust in any appreciable quantity.

T'herefore, until high pressure distribution came into practice, and while the use of natural gas or naturel gas mixtures vvere less wiclespread, very little clifficulty was experiencecl with the formation of dust in mains from the products of corrosion.

In ether words, as long as a man is uscd for distributing ordinary wet manufactured gas very little trouble With dust resulting from corrosion is experienced. However, when the servic is changed over to a manufactured gas of 1ovv moisture content, or over te natural gas or natural gas mixtures which are characterized by very low moistur content, the moisture on and in the corrosion products dries out and such products become a serious source of dust.

'I'he presence of conscierable quantities of dust in the gas flowing through the mains of a distribution system is very undesirable because dust tends to clog up customer service connec tions, interferes with the proper operation of meters, and tends to clog up burners and pilot outlets.

Under extreme conditions corrosion may be so severe as to form a serieus obstrueton in the man tself by reducing ts eflectlve cross-sectional area such as by the accumulation of dust in ples in the main.

A number of methods of correcting dust troubles have been proposed and used.

For instance, excavations have been made at suitably spaced points along the main, say, every 300 feet, the main severed at each excavation and the accumulation removed mechanicaly.

This has been done by drgging a ball of chan back and forth through the disconnected section and increasing the size of the hall as more and more of the produets of corroson have been removed. In some instances, a cutter has been substituted for the ball of 'chain.

In another method a compressor is conformed to function as a sucton device for sucking air through the disconnected man section, and the dust is collected in a bag in a marmer customary in the operation of the ordnary vacuum cleaner.

It will be apprecated that eitherof the foregoing methods of overcoming dust troubles is very expensve in view of the immense amount of labor involved. Furthermore, both methods put the main out of service durng the treatment.

The use of steam for dust laying has the disadvantage that the deposted moisture dries out as soon as steamng is stopped. As far as I am aware the same also applies to the fogging of oil nto the mains, since the oil whlch it has been necessary to use for successful foggng has had to be so light as to make t appreciably volatile.

Furtherrnore, since the corrosion products comprise not only ordnary ron rust but also a varety of other compounds resultng from the action of hvdrogen sulficle, hydrocyanic acid, naphthalcne, and other corrosive substances, the

problem of wetting down the dust, of wetting the and operate to exclude meny types of treating substances from contact with sources of dust end/or with joint packings where treatrnent of the letter is desireci such as with a lo uid capa.ble of swelling nemp and jute to the same extent as water.

A-eature of the invention is to provide en improved dust laying end/or joint sealing cornposition which possesses sufficent solvent power with respect to tar, resin anci gum to ceuse the treating oonstituent or constituents of the composition zo wet and be absorbed by accumulations of dust end/or cellulosie fiber packing Wth sufficient rapidity or praeticable purposes.

Another feature of the invention is to provide a dust laying end/or joint seaiing composition having improved wettng quelities not only or ter, resin end. gum, but also for the metal the main wells.

Another feature of the nvention is te provide a new article of manufacture and a process or makng the same.

Other features of the invention will become, more apparent to persom, skilled in the art as the specficetion proceeds.

I have diseovered that a liquid mixture cornprising a non-cyclic high boiling alphatic alcohol end monophenyl ether of ethylene glycol is excellently adapted (a) te wet, hold end/or bind dust particles end to coat dust sources; (b) to soften or dissolve ter, resin end/or gum Which may cover dust sources or form incrustations wr,h dust deposits; and (0) to spread and climb upon the walls of the gas main am:l throughout the sources of dus'r.

The non-cyclic high bolling alphatic alcohol may be 0ne which is capable of swelling cellulosc fiber paoking to the serne extent as water of. which ethylene glycol, dethylene glycol, mono methyl ether of ethylene glycol, mono methyl ether of diethylene glycol and glycerine ere outstending examples.

The tar resin and gum penetrating power of monophenyl ether of ethylene glycol and its wetting and elirnbing aeton greatly improve the action of such tieating lquids by dissolving or softening ter resins end gum en the pecking ami assisting the swellng agent to climb and wet the packing.

Any desired quantity of my mono phenyl ether of ethyene glycol may be aclrnixed with such dust 1aying end/or cellulosic fiber swelling iiquids according to the results desired, such as from 5 to 20% in the case of cellulosc fiber swelling liquids.

When more drastc treatrnent is required to penetrate incrustationg lerger percentages are recommended.

'I'he treating liquid mey be applecl to the interior surface of a pipe section during or after the assembly of the pipe sections to form the main. 'I'hs mey be accomplished in any desred marmer such as by spraying, brushing, or otherwise.

If the main is alreedy in service, sections of the main may be "blocked o by means of inflated bags or other means, and the sections then completely filled with the liquid after which the liquid een be dreWn off end re-useci.

On the other hand, the liquid may be sprayeci into the gas by the oggng procedure earlier mentioneci so that the dust sources a.bsorb the liquid from the ga stream or, in other words. so that the liqud is deposited from the gas stre;em onto the sources of dust.

In another method of applicetion the liquicl is introduced. into the man at high ponts and allowed to run by gravity to 10W ponts where the excess can be drawn 01. An examination of mains treated in this marmer shows that my composition has greatly improved elirnbing properties.

Another method comprses inserting a, long length of hose into the main with a spray at its end, or with a plurality of sprays distributed along its length, and pumpng the treeting liquid nto the hose while withdrawing the hose either continuously or ntermittently orother- Wise, or while the hose remans stetibnary.

In the last three methods of application service on the line need not be interrupted Dustsources become coated with the treating liquid. 'I'he wet- Figure 2 is a cross-section on line 2-2 of Figure 1.

In the drawing the g.s main i 6 is shown with 2. joint comprising bell li and spigot l2 fitting wthn said bel1 and spaced therefrom. In -the space between the bell and the spigot is celluloslc fiber pecking I'3 which may be terrecl or untarred, and a, seel M of leed or other suitable meterial or holding the paokng in place. The treating lquid i4 as illustrated is bing run through the main by gravty. It contacts the bottom of the rnan and any deposits accumuleted thereon. It also contacts the paeking at space i which space is left between the spigot and the shoulder of the bell to provide for expanson and eontraction due to temperature changes. "Ihe packing absorbs the liquid at I 6 and the liquid climbs and is carried up in the packing as shown by the outer group of arrows in Figure 2. If one or more substance capable of swelling the packing such as ethylene glycoldiethylene glycol, mono methyl ether ofethS/lene glycol, mono methyl ether of diethylene glyl and glycerine is present thepackin is swoll to substantially the same extent as with water. 'I'he treatng liquid also climbs up the metal walls of the main as illustrated by the inner group of arrows in Figure 2 to coat dust sources in additon to those along the bottom of the main.

The bulk of the treatng liquid, of course, remains in the main only during the time that.its flow from the point of introducton to the point of removal Which usually is the nearest drip.

Any ether means for applying the 'treating liquid to the packing end/or to the interor of the conciuit may be employed. For instance, in the case of large diameter mains the level of the liquid i5 inay be raised or may be made to fill the entire main if desired, or the spray or fogging methods may be employed.

In the case of a. welded main, or ether main havng jonts in whch cellulosie fiber packing is not present, the treatment becomesprimarily one of clust leying. Likewise, whenmy mono phenyl ether of ethylene glycol is employed with these non-cyclic high boiling aliphatic alcohols which are ncapable of swelling the paokin such as certain of those dsclosed in my parent applica# tion, the treatment becomes more essentally one lected from a group consisting of ethylene glycol,

of dust layng regardless of the type of main treated, except in so far as a 1qud seal is formed in the interstices of the packng.

Whi1e the inventon has been described in connecton with gas mains it is to be understood that it is applicable to any part of a gas distribution system wherein similar problems may arse. It is also to be understood that the various agents referred to herein may be used ether In the pure or commercially pure form, or in any other suitab1e form including the commercial and crude forrns.

It is to be understood that the above particu- 1ar descripton is by way of illustration and that changes, omssons, addtions, substtutions, end/or modiflcatons might be made within the scope of the claims without departing fromthe spirit of the invention.

For instance, other tar penetratng agents or other sutable material may be added in addition to my monophenyl ether of ethylene glycol.

The terms comprises and comprising are used in the claims in their usually accepted meanings which do not exclude other steps or the presence of substances other than these specifica1ly rected.

I claim:

1. A method for reducing gas lea.kage through cellulosic fibrous packing in a joint of a gas distributon system, comprising impregnatng said packing with a cellulosic fiber swellng agent seleeted from a group consistlng of ethylene g1ycol, diethylene g1ycol, mono methyl ether of ethylene glycol, mono methyl ether of diethylene glycol, and glycerine by bringing said agent nto contact with said packing in the presence of mono phenyl ether of ethylene glycol.

2. A method for laying dust in the interlor of a gas distributon conduit havng dust dposits along the bottom therecf, comprsng envelopng said dust deposts with a dust laying liquid sedethylene glycol, mono methyl ether of ethylene glycoi, mono methyl ether of dethylene glycol, and glycerine by brngng said 1iqud nto contact with said dust sources in the presence of mono phenyl ether of ethylene g1ycol.

3. A joint in a gas distributon systern comprisng spaced cooperating elements, cellulosc fibrous packing such as jute and hemp between said cooperating elements, positioned to form a sca1, and a liqud mixture absorbed by said packing, said liquid mixture comprising mono phenyl ether of ethylene glyco1 and at least one of a group consisting of ethylene glycol, diethylene glycol, mono methyl ether of ethylene g1ycoi, mono methyl ether of dethylene glycol, and glycerine.

4. A joint in a gas distribution system comprsng a be1l, a spgot Positioned within and spaced from said bel1 to form en annular space, an annu 1ar ring o cellulosc fibrous packing in said annular space and continuo1sly contacting said be1l and spigot on its outer and inner peripheries respectively, and a. liquid mixture absorbed by said packing said liqud mixture comprising mono phenyl ether of ethylene glycol and at least one of a group conssting of ethylene glycol, diethylene glycol, mono methYl ether of ethylene glyc0l, mono methyl ether of diethylene glycol,

s.nd glycerine.

5. A method for trezting th interior of a gas distribution system whch comprises applying to the interor of said system a lqud mixture comprsing a non-cyclic high boilng aliphatic alcoho1, and monophenyl ether of ethylene glycol.

6. A gas condut having interor dust sources wetted down with a liquid mixture comprising a non-cyclic high boiling aliphatie. alcohol, and monophenyl ether of ethylene giycol.

JOHN R. SICEEN.

Images