US2047448A - Process and apparatus for reclaiming oily waste packing - Google Patents

Description

5 Sheets-Sheet 1 July 14, 1936. 1.. s. WILBUR PROCESS AND APPARATUS FOR RECLAIMING OILY WASTE PACKING Filed Feb. 6, 1933 JURY 14, 1936. L 5 WILBUR 2,047,448

PROCESS AND APPARATUS FOR RECLAIMING OILY WASTE PACKING Filed FPhv 6, 1933 5 Sheets-Sheet 2 ZL7V 5.572 U5 .5 wa /70196.7)? 2h July 14, 1936. a... s. WILBUR PROCESS AND APPARATUS FOR RECLAIMING OILY WASTE PACKING 3 Sheets-Sheet 3 Filed Feb 6, 1935 Patented July 14, 1936 UNITED STATES PATENT OFFICE PROCESS AND APPARATUS FOR RECLAIM- ING OILY WASTE PACKING 8 Claims.

This invention relates to a process and an apparatus for reclaiming oil from dirty, oil soaked fibrous materials and for cleaning the fibrous material so as to render it fit for reuse.

More specifically this invention relates to a method of reclaiming both the Waste and oil from oil soaked waste, such as the packings used in journal boxes of railroad rolling stock to lubricate the journal bearings. The invention also includes a preferred type of apparatus for carrying out the process.

The journal boxes on railroad rolling stock are generally packed with a fibrous material consisting of a mixture of cotton waste and wool waste to which may be added coconut and other vegetable fibers to maintain the waste in a resillent, flurry condition. The waste is soaked with a lubricating oil generally referred to as car oil and acts as a wick for supplying oil to the journal bearings.

The lubricating waste or packing in the journal boxes accumulates large amounts of foreign matters which become imbedded and entangled in the fibrous material. The foreign materials greatly decrease the efficacy of the lubrication to the bearings and frequently are the cause of hot boxes.

The lubricating or car oil with which the packing is soaked also picks up foreign matters.

All types of solid and liquid particles which may be picked up in the loading and unloading of railroad cars and during their transportation over the railroad right of way are found in the lubricatin packings in the journal boxes.

Examples of some of the foreign materials found in the lubricating waste after use in jourrial boxes are particles of coal, cinders, sand and other siliceous matters, carbon, metals, such as hearing metal and clays. The used packings also contain moisture in appreciable amounts and. frequently contain free water.

The moisture and free water which finds its way into the journal boxes form emulsions with the lubricating oil. These emulsions are of a slimy nature and prevent proper lubrication of the journal bearings.

Railroad specifications require that the journal boxes of all rolling stock be cleaned and repacked definite intervals notexceeding 15 months. The tremendous quantities of oil and. packing used make the replacement costa considerable item in the maintenance of railroad rolling stock and has invited considerable experimentation on methods of reclaiming the lubricating oil and renovating the packing material to renderthe same fit for repacking and relubricating the journal boxes.

'The cleaning and reclaiming of both the fibrous waste and the lubricating oil represents a very difficult task which must be done at a very low cost for commercial success. Furthermore the American Railway Association requires that the reclaimed or renovated packing should not contain strands less than three inches in length and that the dirt and foreign matter shall not exceed 10 5% while the moisture shall not exceed 7%. It is therefore necessary that any reclaiming and renovating process be very efficient.

In my prior application Serial No. 356,972 filed April 22, 1929 (now U. S. Patent NO. 1,896,267,

dated February 7, 1933), of which this is acontinuation-in-part, I have described and claimed a method for cleaning and reclaiming oily fibrous materials, such as dirty waste from journal boxes of railroad rolling stock by washing the waste 20.

in an oil bath, preferably heated to temperatures of 170 to 200 F. The waste and the upper part of the oil bath are agitated during the washing operation by means of compressed air to cause a separation of the foreign matters from the 2 fibers.

I have found in this process that the oil bath could not be heated substantially beyond 200 F. because as the oil approached the boiling point of water (212 F.) a violent foaming occurred. This was due to the presence of water in the waste and oil being treated. The water and oil mixture present always foamed considerably'at the higher temperatures and it was therefore necessary to limit my prior process to temperatures below about 200 F.

It is nevertheless desirable to wash thewaste in hot oil baths to decrease the viscosity of the oil and melt the waxes and other thermoplastic materials which may be contained in the dirty 40 waste. Frequently the waste packing is admixed with very heavy greases, such as pin greases, which are used in the treatment of hot boxes. Because of foaming, however, it has not heretofore been possible to heat the oil above the boiling point of water and, therefore, it has been difficult to reduce the viscosity of the oil mixture sufiiciently to free the dirt, waxes and heavy grease particles.

I have now provided a process for cleaning journal box packings and reclaiming the oil therefrom which is carried out at temperatures considerably above 212 F. Because of the fire hazards the maximum temperature is limited only by the flash' point of the oil.

My new process is operable at higher speeds and yields superior results than prior art processes carried out at lower temperatures.

According to my invention the wash oil in the oil bath is supplied in a dry state or is dried during the washing operation, by means of air, at temperatures below 212 F. and then heated to temperatures substantially above the boiling point of water so that any incoming moist waste will be quickly dried upon contacting with the hot oil. Temperatures from 240 F. to 270 F. and up to 320 F. have been used and found to be desirable, although any temperature above 212 F. is operable. The maintenance of the wash oil at high temperatures prevents the formation of a foaming water and oil mixture, since any water which is introduced during the washing operation is removed in the form of vapor as soon as it contacts the hot oil.

The preferred form of my process also includes agitating the portion of the hot oil bath in contact with the waste material to aid in the separation of the solid particles from the waste. The specific form of my improved process includes agitation with compressed air with or without additional mechanical or fluid agitation. The compressed air greatly aids the volatilization of any water in the waste and aids to prevent the formation of foaming oil-water mixtures.

It is therefore an object of this invention to provide a process for the cleaning of oil soaked fibrous materials which is efficiently operable at high temperatures and at low cost.

Another object of this invention is to remove moisture from the oil contained in dirty oil soaked waste and to dry the waste. Another important object is to remove moisture from the oil and waste being treated before separating the oil from the waste. Another object of this invention is to provide a process for reclaiming oil from waste and renovating dirty oil impregnated waste materials by subjecting the dirty waste to the action of a hot oil bath preferably while agitating the waste and the portion of the bath adjacent the waste.

Another object of this invention is to provide a process for reclaiming oil and renovating dirty oil impregnated journal box packings in a hot oil bath maintained at temperatures above the boiling point of water.

Another object of this invention is to provide a cheap and emcient method for reclaiming journal box packing materials in relatively short washing operations carried out at temperatures substantially above the boiling point of water.

Another important object of this invention is to prepare a renovated waste material by washing dirty waste in an oil bath maintained at high temperatures to prevent foaming and to lower the viscosity of the oil thereby reducing the amount of wash oil in the renovated waste.

Another object of this invention is to provide an apparatus suitable for carrying out the process.

Another object of this invention is to provide a system of apparatus arranged in such a manner as to impart maximum efficiency to the process.

Other and further objects of this invention will be apparent from the accompanying drawings and disclosures in the specification.

This invention (in a preferred form) is illustrated in the drawings and hereinafter more fully described.

On the drawings:

Figure 1 is a side elevational diagrammatic view of apparatus used in a process according to this invention which, if desired, may involve a plurality of washing operations.

Figure 2 is a cross-sectional view of a wash tank according to this invention showing the manner in which the waste material is supported near the top of the oil bath above the heating coils for the oil bath.

Figure 3 is a broken top view of a wash tank showing a mechanically agitated supporting means for the waste material.

Figure 4 is a top view of a wash tank according to this invention showing a stationary supporting rack for the waste material.

Figure 5 is a cross-sectional view of a wash tank showing heating coils and perforated air pipes for heating and agitating the oil beneath the fibrous material supported by a rack as shown in Figures 3 or 4.

Figure 6 is a cross-sectional View, with parts in elevation, of another form of wash tank in which oil is pumped from the tank through perforated pipes situated beneath the waste supporting rack for creating additional agitation of the oil around the waste.

Figure '7 is a broken cross-sectional view taken substantially along the line VIIVII of Figure 6.

Figure 8 is a broken detail view of a type of agitating finger that may be used in the mechanically agitated supporting rack shown in Figure 3.

Figure 9 is a diagrammatic View, partly in cross-section, showing another hookup of the apparatus whereby the oil from a wash tank may be circulated to a heating and/or drying means located outside of the wash tank.

As shown on the drawings:

In Figure 1, the reference numeral l indicates a relatively deep wash tank for containing the Wash oil and for receiving the dirty waste material near the top thereof. After a treatment with hot oil in the wash tank at temperatures preferably above 212 F. for a predetermined length of time the cleaned waste is collected on a drain board 3 allowing the excess oil to run back into the tank. The waste is then inserted into a basket type centrifugal extractor 2. Oil is thus extracted from the waste and allowed to drain back into the wash tank I through a pipe 3a in the bottom of the extractor.

Because of the hot condition of the oil in the waste it is in a very fluid condition and is readily removable from the waste. Consequently the waste after a treatment in the extractor is substantially free from oil.

The fibrous waste material from the centrifugal extractor 2 may. if desired, be inserted into a second wash tank 4 where it undergoes an additional washing treatment with hot oil.

From the wash tank 4. the waste is collected on a drainboard 6 and placed in another centrifugal extractor 5, where the wash oil is removed therefrom and allowed to drain back into the wash tank 4 through the pipe 6a.

The washed waste is now freed from foreign materials and contains only from to lb. of oil per lb. of dry waste. It has not, heretofore, been possible under similar conditions to reduce the waste oil content below 1 lb. per lb. of dry waste but because of the high temperatures used in my process the capillary attraction of the waste for the oil is reduced with the reduction in viscosity of the oil. Therefore the centrifuges remove more oil from the waste than was heretofore possible. This, obviously, aids the quick removal of dirt from the waste since any dirty oil present is more thoroughly removed before the next washing step is effected on the waste. The clean dry waste is next preferably saturated with clean lubricating oil in tank I. The oil in this tank may be heated to about 160 F. and agitated to insure quick saturation of the waste. After a treatment in tank I the waste is placed on a drainboard 8 where the free oil is allowed to drain back intothe tank. The waste is then passed through a wringer 9 for removing excess oil therefrom. The product now contains from 2 to 4 lbs. of lubricating oil per lb. of dry waste and may be directly packed in journal boxes or stored.

The tanks I, 4, and I are heated by means of steam coils fed from a main steam line It through branch lines II, I2, and I3 respectively. The exhaust steam from the steam coils is removed through a discharge line I4.

Compressed air is supplied to perforated coils in the tanks by a pipe line I5. The amount of air fed to each tank may be regulated by valved branch pipes I6, I1 and I8.

Excess oil, introduced into the tanks from the dirty waste inserted therein, may be removed through pipeline 2| to prevent the tanks from overflowing. Valved branch pipes I9, 23 and 28 control the discharge of the oil from tanks 4, I and 1 respectively.

As shown in Figures 2 and 5, the oil wash tank I is provided with heating coils 22 beneath a perforated rack 23 for supporting the waste material 24 near the top of the oil bath. Perforated air coils 25 fed with compressed air from pipeline I5 are disposed between the steam coils 22 for blowing air through the fibrous material 24 to agitate the hot wash oil therethrough and accelerate the separation of dirt therefrom. The air also aids the evaporation of water from the waste to prevent formation of foaming water-oil mixtures.

As shown in Figures 2 and 5 wash oil 30 fills the tank I well above the rack 23 to totally immerse the waste supported thereon. A thermometer 3| inserted in the tank may be used to control a thermostatic valve 32 to regulate the amount of steam fed to the steam coils 22 and thereby control the temperature of the oil bath.

The foreign matters in the fibrous material 24 are washed therefrom and are allowed to settle through the relatively deep wash oil bath 30 to the bottom 33 of the tank. The bottom 33 is preferably at an incline to permit a removal of the settled matter through a port 34 (Figure 2).

The platform or rack 23 supporting the dirty waste near the top of the wash tank I is preferably built up from a plurality of longitudinally extending bars or rods 35 (Figures 4 and 5) supported by rods 36 secured to the walls of the tank I at their ends thereof. The bars 35 are in spaced parallel position thereby forming a grilled rack allowing the free passage of oil, air, undesirable short fibers and solid foreign matter therethrough. As shown in Figures 2 and 5 the waste material 24 is spread in a layer of uniform depth over the rack 23.

The dirty oil impregnated waste material, directly from the journal boxes, and containing the foreign matters described above is thus treated in a hot oil bath at temperatures above 212, preferably above 240 F. while being agitated with compressed air. The waxes and other thermoplastic bodies are rendered fluid by the hot oil and are thus washed out of the waste.

The solid matter in the waste is loosened therefrom by the air agitation and settles through the oil bath to the bottom of the tank where it may be removed as described above. Excess oil may be removed through the pipeline 2| to purifying apparatus where it may be either chemically treated, distilledor filtered to render it fit for lubricating oil. The oil, being in a dry condition, may be readily filtered.

Tank 4 may be identical with tank I or, as shown it may contain a reciprocally mounted rake type of supporting rack such as is shown in Figure 3. Tank likewise may contain this type of rack if desired. As shown in Figure 3, tank 4 is provided with a pair of longitudinally extending fingers 42 and 43 respectively. Said arms 42 and 43 are in spaced parallel relation and loosely fit into the spaces between the arms of the opposing rake so as to leave spaces 44 therebetween.

The rakes 4!! and 4| may be supported on transverse rods 45 anchored in the walls of the tank similar to rods 36 used in tank I to support the rack 23. Each rake and 4| is provided with an arm extending through the wall of the tank 4 and connected with an eccentric device 41. When the eccentric devices 41 are actuated, an alternative reciprocating action is imparted to the rakes 40 and 4| so as to pull apart the fibrous material without tearing the same and thus restore its original fiuffiness. The agitation produced by the rakes greatly aids the loosening of foreign material embedded in the waste and speeds up the cleaning operation.

If desired each rake finger 42 and 43 may be designed as shown in Figure 8. As therein illustrated the rake finger is provided with a plurality of rounded teeth 48 which engage the fibrous material and impart the action of the reciprocating rakes to the material. The combined mechanical agitation and agitation by the compressed air from the air coils 25 quickly removes foreign material from the waste.

The process described above is a batch process for treating predetermined amounts of waste in each tank. When each washing operation is finished the waste is transferred to a centrifugal dryer or wringer and then into the next tank for further treatment.

In Figure 6, there is disclosed an alternative arrangement in which the fibrous material 24 on a rack 23 is subjected to additional agitation by pumping some of the oil from the oil bath 39 through a pipeline 5% by means of a pump 5| and into a perforated coil 52 having perforations opening beneath the rack 23. Gil is thus ejected upwards through the rack 23 to impart additional agitation to the fibrous material.

This fluid agitation may be combined with mechanical agitation such as by using rakes shown in Figure 3 and may also be combined with the air agitation as shown in Figure 7. Three sets of coils are thus positioned beneath the rack 23. Coils 52 are for carrying oil from the pump 55 to eject it through the rack 23 to agitate the fibrous material 24 thereon. Coils 22 are the heating coils described in Figure 2 while the smaller coils 25 between the steam and fluid coils are for conducting compressed air as described in Figure 5.

As shown in Figure 6, the temperature of the oil bath is controlled by a thermostatically operated valve 32 which has been described above.

In Figure 9 I have disclosed another arrangement for drying the oil from a bath in the Wash tank. Oil 30 from a wash tank 55 is pumped through a pipeline 56 into an open tank 51 by means of a pump 58. If desired a perforated coil 59 may be used to feed the oil to the tank in comminuted form. A steam coil 60 is provided to heat the oil 30 in tank 51. A perforated coil Bl for compressed air aids the evaporating of moisture from the oil. The hot dry oil from tank 51 is circulated to the wash tank 55 through a pipe 62. The wash tank 55, like tank I may be heated with steam through pipe 1 I. Likewise the tank may also contain coils for compressed air from pipe I 8, and means for fluid and mechanical agitation.

It is evident from the above description that my invention in its broader sense, includes both the cleaning and renovating of dirty oil impregnated fibrous materials such as packings from journal boxes and the reclaiming of the oil in the fibrous material. The reclaimed oil is readily purified by filtration alone making it suitable for reuse as a lubricant. The fibrous material has its original colors restored as well as its original fiufiiness and soft texture. Its moisture content is below 1% while the foreign matter or dirt content is below 2%. The renovated cotton waste furthermore has an ash content below 0.2%. These properties are far superior to those required by railroad specifications as pointed out above.

The invention comprises washing in any oil at temperatures above the boiling point of water so as to maintain the oil in a dry condition. I have found that the dry oil may be readily filtered free from foreign materials and directly used as a lubricant whereas heretofore the oil from the wash tanks was in a slimy unfiltrable condition necessitating distillation or chemical treatment before it could be reused as a lubricant.

As an aid to maintaining the oil in the wash tanks in a dry state, I have provided means for drying the oil such as the heating means, the fluid agitation by recirculation of part of the oil, and the compressed air feed means. As illustrated in Figure 9 of the drawings, the drying operation may be carried out in a tank outside of the wash tanks.

My process includes an agitation of the waste being washed with mechanical means which may also be combined with an air or fluid agitation as well as all three means in combination. The maintenance of the oil at temperatures about 240 F. or above while blowing dry air through the oil will remove moisture at a rapid rate. The high temperature melts any waxes or greases in the waste and reduces the viscosity of the wash oil sothat it washes like gasoline.

I have found in actual commercial operation that the original flufiiness of the dirty waste may be restored in two minutes of boiling in a wash tank such as is shown in Figure 1. The wash oil used is preferably the same oil as is used in lubricating the journals.

The air agitation may be carried out at lower pressures than heretofore used because of the higher temperatures maintained in the oil bath. Thus where pressures of from 25 to 50 pounds per square inch have heretofore been used I may use pressures from 2 to 10 pounds. If desired, the air may be heated before blowing it into the Wash tanks.

While the washing operations such as are carried out in the first tank are maintained at temperatures preferably between 240 and the flash point of the oil, the subsequent operations after the waste has been substantially dried may be carried out at lower temperatures. Thus the washing operations in the second step and the oil saturation step may be eifected at temperatures between 160 to 200 F. However, it is to be understood that the subsequent rinsing and washing operations may be carried out at the higher temperatures if desired.

I am aware that many changes may be made and numerous details may be varied through a wide range without departing from the principles of this invention and I, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior art.

I claim as my invention:

1. The process of renovating the waste and reclaiming the oil from journal box packings which comprises subjecting the dirty oil impregnated waste to the action of a pond of hot oil at temperatures above 240 F., allowing the foreign materials to settle out from the waste to the bottom of the oil pond, removing the waste material from the oil pond after a treatment therein for a predetermined length of time, removing free oil from the waste material, returning said oil to the oil pond, subjecting the partially cleaned waste materials to another hot oil treatment, removing the oil from the waste after the second treatment, rinsing the cleaned waste in another hot oil pond and removing the excess oil from the thoroughly cleaned waste to produce a product useful for repacking the journal boxes.

2. The process of cleaning dirty oil impregnated waste which comprises immersing the dirty waste in a pond of hot oil maintained at temperatures substantially above the boiling point of water but below the flash point of the oil, simultaneously blowing air through the upper portion of the oil pond and through the waste to aid in maintaining the oil dry and in the removal of foreign materials imbedded in the waste, allowing the foreign materials to settle to the bottom of the oil pond and subjecting the so treated waste to additional washing operations to remove further quantities of foreign materials therefrom.

3. The process of renovating dirty oil impregnated waste material which comprises spreading a layer of the dirty waste material in the upper portion of a hot oil bath, maintaining the oil at temperatures substantially above 212 F. and

simultaneously bubbling dry oil under pressure into the oil bath beneath the waste material to agitate said waste and effect a precipitation of foreign materials therefrom.

4. The process of reclaiming and renovating dirty oil impregnated waste which comprises washing the waste in a pond of hot oil, maintaining the oil at temperatures substantially above 212 F. but below the flash point of the oil, drying the oil at temperatures below the distilling point of the oil by circulation through a dryer and recirculating the dried oil back to the washing pond to prevent the formation of a foaming oil-water mixture therein.

5. In the process of cleaning and renovating dirty oil impregnated waste material by washing the dirty waste in a hot oil bath maintained at temperatures above the boiling point of water, the steps which comprise agitating the waste material with compressed air, further agitating the waste material with mechanical means and producing additional agitation by propelling oil through the waste.

6. In the process of cleaning dirty oil impregnated waste material by washing the dirty waste in a hot oil bath, the step which comprises maintaining the oil bath in a substantially dry condition to prevent the formation of water-oil emulsions by circulating the oil from the oil pond through a dryer heated at temperatures above the boiling point of Water but below the distilling point of the oil to remove therefrom any Water collected from the Waste and recirculating the dried oil back to the oil pond.

7. Apparatus for cleaning and renovating dirty oil impregnated waste material which comprises, in combination, a tank for containing an oil bath, a perforated rack in said tank near the top thereof for receiving the dirty waste thereon, a steam coil in said tank beneath said rack, means for removing dirt from the bottom of said tank, and a perforated air supply coil adjacent said steam coil for agitating the oil and waste near the top of the tank.

8. Apparatus for washing dirty oil impregnated waste which comprises, in combination, a tank for receiving a body of oil, means for heating said tank, perforated pipes for ejecting air into the tank near the top thereof, a movably mounted grilled rack for supporting the waste material 10 near the top of the tank and means for agitating said rack.

LAWRENCE S. WILBUR.

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