US3767591A - Container of a malodorous warning liquid for malfunctioning mine ventilation - Google Patents

Abstract

THE MALODOROUS WARNING COMPOSITION OF MATTER INCLUDES THE INGREDIENTS OF A LIQUID MERCAPTAN MIXED WITH A NONFLAMMABLE SOLVENT HAVING A RELATIVELY LOW VAPOR PRESSURE, SUCH AS TRICHLOROMONOFLUOROMETHANE, AND AN INERT GAS SUCH AS NITROGEN UNDER PRESSURE, TO FORM A MALODOROUS MIXTURE FOR INTRODUCTION INTO PRESSURIZED AIR BREATHING SYSTEMS, SUCH AS FOR MINES, TO WARN A PERSON OF DANGER BY THE ODOR. THIS NEW COMPOSITION OF MATTER HAS NO NEED FOR EXTERNAL MEANS OF HEATING OR COOLING THE MIXTURE FOR INTRODUCING IT INTO THE PRESSURIZED AIRE BREATHING SYSTEM. THE PROCESS FOR ITS PREPARATION INCLUDES THE STEPS OF INTRODUCING AN INERT GAS UNDER PRESSURE INTO A SUITABLE CONTAINER IN WHICH THE MERCAPTAN AND SOLVENT HAVE BEEN PREVIOUSLY PLACED, AND PRODUCING A PRESSURE INTERNALLY OF ABOUT 250 TO 300 POUNDS PER SQUARE INCH, AND SEALING THE CONTAINER BY A NEEDLE VALVE OR OTHER SUITABLE MEANS.

THE WARNING DEVICE INCLUDES THE MALODOROUS COMPOSITION OF MATTER TOGETHER WITH A SUITABLE HIGH PRESSURE CONTAINER EQUIPPED WITH A HIGH PRESSURE NEEDLE VALVE. THE WARNING SYSTEM INCLUDES THE WARNING DEVICE TOGETHER WITH AN ADAPTER ON THE END OF THE NEEDLE VALVE, TO WHICH IS CONNECTED A FEEDER TUBE MEANS HAVING A FITTING OR COUPLING FOR CONNECTION OF ITS OUTER END TO A VALVE OF ITS OUTER END TO A VALVE OF A PRESSURED AIR BREATHING SYSTEM OF A FACILTIY SUCH AS A MINE.

Description

OCL 1973 A. B. SELLECK CONTAINER OF A MALODOROUS WARNING LIQUID FOR MALFUNCTIONING MINE VENTILATION Filed July 23, 1971 f/vvEA/Tofie.

945527 B. SELLECK 3 9 H 99 IQTTO/QNEV- United States Patent 3,767,591 CONTAINER OF A MALODOROUS WARNING LIQUID FOR MALFUNCIIONING MINE VENTILATION Albert B. Selleck, 19310 Caladero St., Tarzana, Calif. 91356 Filed July 23, 1971, Ser. No. 165,537 Int. Cl. C09k 3/30 US. Cl. 252-408 2 Claims ABSTRACT OF THE DISCLOSURE The malodorous warning composition of matter includes the ingredients of a liquid mercaptan mixed with a nonfiammable solvent having a relatively low vapor pressure, such as trichloromonofluoromethane, and an inert gas such as nitrogen under pressure, to form a malodorous mixture for introduction into pressurized air breathing systems, such as for mines, to Warn a person of danger by the odor. This new composition of matter has no need for external means of heating or cooling the mixture for introducing it into the pressurized air breathing system.

The process for its preparation includes the steps of introducing an inert gas under pressure into a suitable container in which the mercaptan and solvent have been previously placed, and producing a pressure internally of about 250 to 300 pounds per square inch, and sealing the container by a needle valve or other suitable means.

The warning device includes the malodorous composition of matter together with a suitable high pressure container equipped with a high pressure needle valve. The warning system includes the Warning device together with an adapter on the end of the needle valve, to which is connected a feeder tube means having a fitting or coupling for connection of its outer end to a valve of its outer end to a valve of a pressured air breathing system of a facility such as a mine.

BACKGROUND OF THE INVENTION (1) Field of the invention This invention relates to a malodorous composition of matter for introduction into a pressurized air breathing system, such as those used for mines, to warn a person of danger by the malodorous smell. The process for its preparation involves the mixing of a mercaptan with a nonflammable solvent with a relatively low vapor pressure over a wide range of temperatures and subjecting the resulting mixture with an inert gas under pressure for expelling the composition of matter into a pressurized air breathing system.

The invention also includes the combination of a malodorous composition of matter with a suitable high pressure container equipped with a high pressure needle valve, to form a warning device. The invention also includes a mine warning system when the warning device is equipped with an adapter connected to a tube means leading to a valve of a pressurized air breathing system of the desired facility.

(2) Prior art Applicant knows of no prior art making use of the particular combination of ingredients disclosed in this application, or of a process for its preparation as described herein, or of a combination of such ingredients together with a high pressure container and needle valve, or additionally of an adapter and feeder tube means.

SUMMARY OF THE INVENTION The malodorous composition of matter has three basic ingredient: a mercaptan, to produce the warning odor; a solvent for the mercaptan, which serves to reduce the 3,767,591 Patented Oct. 23, 1973 flammability and explosive qualities of the mercaptan by acting as a diluent and nonflammable solvent medium; and an inert gas under pressure to force the composition of matter from a high pressure container into the pressurized air breathing system. 7

For relative ease in preparing the malodorous composition of matter, a liquid mercaptan at ambient temperatures is preferred. Such mercaptans include methyl mercaptan, ethyl mercaptan, both n-propyl and iso-propyl mercaptan, referred to hereinafter as propyl mercaptan, both secondary and tertiary butyl mercaptan, both referred to hereinafter as butyl mercaptan, and tetrahydrothiophene, referred to hereinafter as thiophane.

Other suitable malodorous compounds for this composition of matter include dimethyl sulfide, and ethyl iso-propyl sulfide.

Since all of these compounds are flammable or explosive or both, it is highly desirable to incorporate them into a nonfiammable solvent for safety and ease in handling and application. Such a solvent must also have a relatively low vapor pressure over a relatively wide temperature range, which may be defined as a maximum vapor pressure of not over 40 pounds per square inch at 1 atmosphere, i.e. sea level, at a maximum temperature of degrees Fahrenheit. Such suitable solvents are trichloromonofluoromethane, trichlorotrifluoroethane, 1,1,l-trich'loroethane, also known as methylchloroform, methylene chloride, trichloroethylene, and perchloroethylene.

Since the vapor pressure at sea level of these solvents is lowered as the temperature is decreased below the maximum temperature of 130 degrees Fahrenheit, the only limitation as to cold temperatures is the elfectiveness of the inert gas under pressure to expel the composition of matter from the container into the pressurized air breathing system.

The usual pressurized air breathing system for mines in the United States averages about pounds per square inch, With respect to the amount of pressure used. So long as the internal pressure in the container holding the malodorous composition of matter exceeds 150 pounds per square inch, no difiiculty exists in using the warning mixture.

Nitrogen gas is a particularly suitable inert gas for use in preparing the malodorous composition of matter. When the container has been charged with nitrogen gas to an internal pressure of about 275 pounds per square inch at room temperatures, sufficient pressure exists to expel the contents of the container at temperatures as low as 30 F. into pressurized air breathing systems maintained at a pressure of 150 pounds per square inch. Also, the increase in internal pressure of such a container, thus charged with nitrogen gas, at a temperature of 130 is insufiicient to burst the standard high pressure cylinder used as a container for the malodorous composition of matter.

Various other inert gases having similar characteristics as nitrogen gas may also be used. For example, carbon dioxide gas or nitrous oxide gas may be used without adversely aifecting the results obtained by my invention.

Once the malodorous composition of matter has been prepared under the desired pressure in a high pressure container, the container may be stored for an indefinite period of time Without adversely affecting the operation of my invention. Moreover, when the container is to be employed, it may be used without any other preparation of heating or cooling of the contents, before introducing the contents into a pressurized air breathing system.

The container is preferably a high pressure cylinder capable of withstanding up to 375 pounds per square inch pressure or more at sea level, and equipped with a high pressure needle valve having a corrosion resistant seat of Teflon or other suitable material. The container and valve,

3. together with the malodorous composition of matter, make up the mine warning device.

When the warning device is equipped further with an adapter and feedertube means, for attachment to a valve of a pressurized air breathing system for a facility such as a mine, the invention then becomes a warning system.

It is, therefore, an object of this invention to provide a malodorous warning composition of matter which is relatively easy to prepare and to store for long periods of time without deterioration or special handling.

Another object of this invention is to provide 21 malodorous warning composition of matter which can be contained in a high pressure cylinder and used immediately over a range of temperatures from about F. to about 130 F. without the necessity for heating or cooling the container or its contents.

A further object of this invention is to provide a malodorous warning composition of matter which can be prepared from readily available materials and at a relatively inexpensive cost.

A still further object of this invention is to provide a malodorous warning composition of matter which is relatively safe to use both from the aspect of being relatively nontoxic and relatively nonflammable.

A yet another object of this invention is to provide a warning device capable of containing said malodorous composition of matter under pressure and of permitting said composition of matter to escape through a valve means.

A yet further object of this invention is to provide a warning system having the capability of containing and delivering said malodorous composition of matter under pressure when desired into a pressurized air breathing system of a facility such as a mine, over a range of temperatures from about 10 F. to about 130 F., without the necessity for heating or cooling the container of the warning system or its contents.

These and other objects will be more readily understood by reference to the following specification and claims, taken in conjunction with the accompanying drawing, in which FIG. 1 is a side elevational view of the invention in position for introducing the malodorous composition of matter into a pressurized air breathing system of a facility, said air breathing system being shown in part and by dotted lines.

DESCRIPTION OF PREFERRED EMBODIMENTS The warning device 10 has a high pressure cylinder 12 with an internal capacity of about 75 cubic inches. One end of the cylinder 12 is equipped with a high pressure needle valve 14 with a handle 15 to open and close the valve 14. Preferably, the valve 14 is equipped with a corrosion resistant seat made of Teflon or other corrosion resistant material. An adapter 16 is attached to the outer end of the valve 14.

The malodorous warning composition of matter 18 included and contained in the warning device 10 occupies only part of the interior of the cylinder 12, the rest being taken up by the compressed inert gas 20.

Warning system 22 includes warning device 10 with malodorous composition of matter 18 and compressed inert gas 20, together with feeder tube 24 having a flared threaded fitting 26 connected to adapter 16 at one end, and having a similar flared threaded fitting 27 at its other end connected to adapter 28 threaded on pipe nipple 29 of valve 30 opening into the pressurized air breathing system 32 of the facility, shown in part and by dotted lines in the drawing. Various alternative connecting means may be used.

The same general procedure is used in the preparation of the malodorous warning composition of matter, regardless of the various ingredients used in each of the three categories making up the malodorous warning composition of matter-the substance producing the warning 4, odor, the solvent, and the inert gas. Although not essen? tial, I have found it preferable to add an additional step in the preparation of the malodorous composition of matter of agitating the contents of the container after being charged with the inert gas, and then re-charging the container to allow for a decrease in internal pressure due to the partial absorption of the inert gas under pressure by the liquid contents. In this matter, a uniform internal pressure may be achieved and maintained inside the container.

EXAMPLEl The preparation of the malodorous composition of matter may be accomplished at ambient temperatures such as room temperature of about 70 F. or at other convenient ambient temperatures.

About grams of ethyl mercaptan is placed inside a cylinder 12 capable of withstanding relatively high internal pressure such as 300 to 350 pounds per square iiich at sea level and equipped with a high pressure needle valve 14. A suitable internal capacity of the cylinder is about 75 cubic inches.

Next, about 450 grams of solvent, trichloromonofluoromethane is added to the 100 grams of ethyl mercaptan inside the cylinder.

Then, sufiicient nitrogen gas under pressure is introduced through the needle valve 14 into the cylinder .12 to produce an internal pressure of about 275 pounds per square inch inside the cylinder 12 at ambient "temperatures.

Optionally, and preferably, the cylinder 12 is then agitated for a minimum period of time of about 30 seconds to mix the liquid contents thoroughly inside the cylinder 12 and to complete whatever absorption may occur of the inert nitrogen gas by the mixture of ethyl mercaptan and trichloromonofluoromethane solvent. su'c'h absor'ption may vary from 3 to 6 percent by weight of the nitro gen gas and may lower the initial internal pressure of the cylinder 12 from about 275 pounds per squareinch" to about 240 to 245 pounds per square inch. Since siich lower pressures are more than ample for introduction of the malodorous composition of matter into conventional pressurized air breathing systems of about pounds per square inch in the United States, rercharging of the cylinder 12 with nitrogen gas back up to the initial internal pressure of about 275 pounds per square inch' is not actually necessary.

To maintain uniformity of pressure, however, additional nitrogen gas under pressure is introduced through the needle valve 14 of the cylinder 12 until the initial internal pressure of 275 pounds per square inch is restored, as indicated by the pressure neutralization gauge -of a nitrogen gas reservoir tank.

The needle valve 14 is then closed and capped with a safety cap for storage purposes. The charged cylinder may then be stored as needed without any special precautions of locations or of ambient temperatures.

In the example given above, the amount of nitrogen gas by weight to maintain an internal pressure of about 275 pounds per square inch after agitation of the cylinder 12, is about 30 grams by weight at ambient temperatures.

In use, the warning device 10 is placed in a vertical" position with its needle valve 14 at the bottom. The

safety cap (not shown), if on the needle valve 14, is

removed. Fitting 26 of feeder tube 24 is connected to the adapter 16 on the outer end of the needle valve 14 and (fitting 27 on the other end of feeder tube 24 is connected;

substantial part of the inert gas 20 are exhausted into the pressurized air breathing system 32 in about 5 seconds, until the remaining inert gas in the cylinder 12 reaches an equilibrium pressure with the pressure of the pressurized air breathing system 32.

Valve 30 of the pressurized air breathing system 32 is then closed, and the warning system 22 is then removed from its connection with the pressurized air breathing system 32.

If desired, the cylinder 12 may be disposed of, or reused as part of another warning device and warning system 22. Due to the novel features of my invention, the warning system 22 is fully effective at ambient temperatures ranging from a minimum of about 10 F. to about 130 F. without any heating or cooling of the cylinder 12, and without any special preparation, where the pressurized air breathing system of the mine or other facility is at a pressure of about 150 pounds per square inch.

EXAMPLE 2 The steps of Example 1 are repeated with the substitution of about 100 grams of methyl mercaptan instead of ethyl mercaptan and the same results are obtained.

EXAMPLE 3 The steps of Example 1 are repeated with the substitution of about 450 grams of trichlorotrifiuoroethane instead of the trichloromonofiuoromethane and the same results are obtained.

EXAMPLE 4 The steps of Example 2 are repeated with the substitution of about 450 grams of trichlorotrifiuoroethane instead of the trichloromonofluoromethane and the same results are obtained.

The ratio of parts by weight of the liquid malodorous substance and the solvent may vary from 1 part of the former to 2 parts of the latter, as a maximum, to about 1 part of the former to about 6 parts of the latter, without adversely affecting the results. Also, the amount of inert gas may vary from .2 to .4 parts by weight Where the ratio of liquid malodorous substance and solvent is 1:2 and 1:6 respectively, thereby producing a variance in internal pressure of a 75 cubic inch high pressure cylinder from about 200 pounds per square inch to about 430 pounds per square inch at room temperatures of about 70 F. without adversely afiecting the results. Of course, for the higher pressures, suitable high pressure cylinders must be used that are capable of withstanding such higher pressures.

If it is desired to use high pressure cylinders of greater or lesser capacity than 75 cubic inches internally, the various amounts of ingredients can be adjusted in proportion to the increased or diminished capacity of the cylinder so that effective operating pressures may be obtained internally over the temperature range of 10 F. to 130 F. The higher internal pressures, i.e. over 275 pounds per square inch, may be elfectively used where the expected operating temperatures are below 30 F. The only essential requirement for operation of my invention is that the internal pressure of the charged cylinder be in excess of the pressures used in the pressurized air breathing system of the particular facility where the malodorous warning composition of matter is to be introduced.

Although I have described preferred embodiments of my invention, it is understood that the scope of the invention is not limited thereby, but numerous variations in ingredients and procedures are possible without departing from the spirit and scope of the invention as claimed hereinafter.

What is claimed is:

1. In combination, a high pressure closed container capable of withstanding internal pressure containing therein about 1 part by weight of a liquid malodorous substance selected from the group consisting of methyl mercaptan, ethyl mercaptan, propyl mercaptan, butyl mercaptan, thiophane, dimethyl sulfide, and ethyl iso-prop'yl sulfide, from about 2 to 6 parts by weight of a nonflammable solvent for said liquid malodorous substance, said solvent having a maximum vapor pressure of less than 40 lbs. per sq. inch at sea level at a temperature of about F., said solvent being selected from the group consisting of trichloromonofluoromethane, trichlorotrifluoroethane, 1,1,1-trichloroethane, methylene chloride, and trichloroethylene, and from about 0.2 to about 0.4 part by weight of an inert gas under pressure, said inert gas being selected from the group consisting of nitrogen, carbon dioxide, and nitrous oxide.

2. The combination of claim 1 wherein the liquid malodorous substance is methyl mercaptan or ethyl mercaptan, the solvent is trichloromonofiuoromethane or trichlorotrifluoroethane and the inert gas is nitrogen.

References Cited UNITED STATES PATENTS 3,475,146 10/1969 Olund 252-408 3,099,603 7/1963 Banker et al. 42447 OTHER REFERENCES 'Aerosol Review, 1966, p. 4 and 23, TP 244.

Eckton, J. of the Soc. of Cosmetic Chemists, pp. 389 and 390, August 1963, 424/47.

Herzka, 'International Encyclopedia of Pressurized Packing (aerosol), pp. 265-266 and 510, pub. 1968, by Pergamon Press, New York, N.Y., TP 244.

Herzka, Pressurized Packing (aerosol), pub. 1958, pp. 93-96, QD549 H47.

DONALD LEVY, Primary Examiner US. Cl X.R.

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