JPH0819424B2 - Waste oil reuse device and method - Google Patents

Abstract

An apparatus and a method are provided for reclaiming a useful oil product from waste oil, such as used lubricating oil. The apparatus comprises an oil feed means (19), a boiler (18), a heater (17) and separating means (18,48). The heater (17) is used to heat the waste oil in the boiler (18) to a temperature such that lighter hydrocarbons of the waste oil volatilize, but such that heavier hydrocarbons remain unvolatilized, trapping contaminants therewith. The separating means separates the volatilized lighter hydrocarbons from the unvolatilized heavier hydrocarbons and contaminants.

Description

The present invention relates to a device and method for reusing waste oil, and more particularly to a device and method for removing various contaminants present in waste oil that are unsuitable for reuse as heating fuel, diesel fuel and the like.

As used herein, the term "waste oil" refers to oils used as motor oils or other lubricating oils, or as pressure oils or in other such applications. In use, these oils are considered regularly. The oil discharged and collected typically contains impurities, metal particles (including heavy metals such as molybdenum, chromium, cadmium and copper), oxides and salts, gasoline and gasoline additives (such as tetraethyl lead), As well as a substantial amount of contaminants which may include detergents and performance additives.

Millions of gallons of such waste oil are generated each year in North America. In the past, waste oil was either used on dirty roads for dust control or simply dumped in sewers or landfills. However, such devolatilization methods are increasingly understood as an unacceptable cause of hydrocarbons to the environment. Refining of waste oil has been used to some extent. However, known methods for refining waste oil require complex chemical treatments and generally do not yield high quality products. Transportation costs further impair the economic potential of this method of treating waste oil.

In the past, it has also been proposed that waste oil be used as heating fuel. However, known types of furnaces for burning such oils have had limited success. Residues build up in the burner during conventional waste oil combustion.
Residues are formed from various contaminants and heavier hydrocarbons that form hard binder resins. As a result, the burner must typically clean the hard residue that has accumulated twice daily. To clean the burner, the furnace must be turned off and cooled. This is very inconvenient and shows a large inefficiency. Further, removal of cooled and hardened residues from burners is a difficult task that typically requires heavy manual labor.

The object of the present invention is to eliminate or reduce the drawbacks of the prior art in this field.

According to a first aspect of the present invention, there is provided an apparatus for recycling useful oil products from waste oil. This device comprises an oil supply means, a boiler, a heater and a separation means. The oil supply means is used to supply waste oil to the device. The boiler is adapted to be fluidly connected to the refueling means and to receive waste oil therefrom. The heater is used to heat the waste oil in the boiler to a temperature at which the lighter hydrocarbons of the waste oil will volatilize but the heavier hydrocarbons will not, and will trap contaminants with it. Separation means separates the lighter volatilized hydrocarbons from the non-volatile heavier hydrocarbons and contaminants. Surprisingly, such a device is simple and easy to produce clean oil products suitable for removing pollutants from waste oil and recycling for various applications, especially as heating fuel or as diesel fuel. And it has been found to provide effective means.

Preferably, the heater of such a device is from an oil burner fluidly connected to the separating means and adapted to receive from the separating means a recycled portion of waste oil drawn from volatilized lighter hydrocarbons and burn it. Become. Conveniently, said separating means is integral to the boiler, said boiler being designed to release a lighter hydrocarbon which has been volatilized, and a heavier hydrocarbon and contaminants which have not been volatilized. A second release conduit made. Most preferably, the apparatus further comprises a condenser for condensing lighter hydrocarbons that have volatilized to produce liquid petroleum products for reuse and also a recycle oil container for storing and storing recycle oil. , And a sludge tank for accumulating heavier non-volatile hydrocarbons and contaminants separated to facilitate periodic removal.

According to a second aspect of the present invention, the lighter hydrocarbons of the waste oil are volatilized, but the heavier hydrocarbons are not, and the waste oil is heated in the boiler to a temperature that traps contaminants therewith, and Subsequently, there is provided a waste oil treatment process comprising the step of separating the volatilized lighter hydrocarbons from non-volatile heavier hydrocarbons and contaminants. Preferably, the temperature is in the range of about 600-800 ° F. Conveniently, the temperature is about 650 ° F. Most conveniently, the volatilized lighter hydrocarbons are subsequently condensed to yield a recycled liquid oil product, at least a portion of which is then combusted in the boiler to further heat the waste oil.

The present invention provides a safe, effective and versatile means for treating waste oil from which useful petroleum products that can be used in many ways, especially as heating fuels or diesel fuels, are then reused. . Sludge by-products derived from heavier hydrocarbons and pollutants must be further discarded. However, it typically represents only about 1/10 of the amount of waste oil fed to the unit. In some cases it is also possible to reuse valuable metals from the sludge product.

The apparatus of the present invention can be manufactured and operated at a small portion of the cost of the refining plant. Thus, industrial and commercial factories (such as car service stations)
And locations where large amounts of waste oil accumulate can be utilized as a valuable by-product rather than having to pay to dispose of it.

In order that the present invention may be more clearly understood,
Reference is made to the accompanying drawings which illustrate the invention.

Referring first to FIG. 1, the apparatus comprises a containment structure 10 having a substantially enclosed first chamber 11 and a substantially enclosed second chamber 12, the first chamber 11 and the second chamber 12 having a common wall. Although substantially separated from each other by 13, they are common walls 13
Are in fluid communication with each other through openings 14 in. The flame chamber 15 in the first chamber 11 consists of a separate flame chamber 16 containing a burner 17 and a distillation boiler 18 in which the waste oil is heated. Waste oil is supplied from the storage tank 19 to the boiler 18 via the float chamber 20. The oil level in the boiler 18 is controlled by the float chamber 20. Float chamber 20 is sealed but vent pipe 21
Pass between the boiler 18 and the float chamber 20 to balance the pressure. The boiler 18 is placed above the flame chamber 16 and the flame chamber 15
The spacing between them is such that the temperature at the height of the boiler 18 is approximately 650 ° F. while the system is operating (ie, burning oil). At this temperature, the lighter hydrocarbons are volatilized and decomposed and they exit the boiler 18 through the discharge pipe 25. The sludge, which is composed of heavier hydrocarbons and contaminants that are not volatilized, gradually accumulates in the bottom portion 23 of the boiler 18. This sludge is emptied into a sludge tank 24 via a discharge pipe 22 and finally discarded. If the sludge is not emptied, the sludge and boiler levels in the boiler 18 will rise to the shut-off level of the float chamber 20 and will eventually be shut off automatically.

Volatilized lighter hydrocarbons from the boiler 18 are discharged from the pipe 25
Through a heat exchanger 26 positioned in front of the blower 27 where they are cooled and condensed. The heat released by the heat exchanger 26 is transferred to the second chamber 12 along the air flow created by the blower 27 and to the first through the opening 14.
Enters chamber 11 and is thus caught again for heating.

The lighter hydrocarbons condensed are thus holding tank 28
Form a recycled liquid oil product that passes through. Recycled oil is then emptied for use somewhere or burner
Is transmitted to 17 via pump 30. The flame chamber 16 is the same as the flame chamber of a conventional oil furnace. Flame chamber 15
The heat from is transferred through the first chamber 11 to a heating conduit 31 which connects to the building heating device. Burning smoke exits through flame tube 32.

The furnace burner 17 may be a simple pot type burner.
Alternatively, a gun-type burner can be used. If a gun-type burner is used, the reclaimed oil must be supplied by a hydraulic pump that is maintained at a temperature of about 650 ° F in a heated water bath, and an in-line heater is used depending on the viscosity of the reclaimed oil. , Must be used to maintain a nozzle temperature of approximately 130 ° F.

FIG. 1 shows a simple embodiment of the device according to the invention in order to illustrate the basic working principle. 2 and 3,
A preferred embodiment of the device of the present invention will be described. For simplicity and brevity, like parts are provided with the same reference numerals used in the simple embodiment of FIG. 1 and the description of those parts is not repeated.

In this embodiment, the supply storage tank 19 is mounted within the containment structure 10. When the level of waste oil in the supply storage tank 19 drops below the preset level, the float switch 40 activates the motorized pump to supply more waste oil from the external receiving storage tank. When power is applied to start the device, solenoid valve 43 is opened to allow flow from supply storage tank 19 and motorized supply pump 45 is activated. Supply storage tank 19
Waste oil from the first passes through a "Y" strainer 41 which removes dirt particles and entrained water. Most of the water carried with a typical waste oil can be removed, but the oil is retained in an external receiving and storage tank. The remaining carried water that is diverted by the "Y" strainer 41 drains to a water trap tank 42 from which water is periodically removed via a water conduit 35 by opening to a valve 36. You can

When the solenoid valve 43 is opened, waste oil is pumped
It is fed to the preheater tank 46 via 45 and also through the needle valve 44. Needle valve 44 can supply waste oil in amounts up to 6 gallons / hour. The supply pump supplies waste oil in an amount of about 4 gallons / hour regardless of the flow rate through the needle valve 44. Thus, throughout operation, the waste oil feed rate varies from about 4 to about 10 gallons per hour.

During operation, the preheater tank 46 will contain about 200-300 of waste oil.
Heat to ゜ F. Waste oil is transmitted from the preheater tank 46 to the boiler 18. In this embodiment, the boiler 18 has an inclined base that rests on a slider 47 so that the boiler 18 can be removed from the flame chamber 15 such as a drawer to facilitate periodic cleaning and the like. Two inclined barriers 48
The sludge that accumulates at the bottom 23 of the boiler 18 extends upwardly from the inclined base and inward from the opposite side of the boiler 18 so that it flows laterally around the barrier 48 below the inclined base. Volatilized lighter hydrocarbons are in the ascending section 49 and hence the discharge tube.
Exit through 25.

When the level of waste oil in the boiler 18 reaches the preset height determined by the bottom level float 72 in the float chamber 20, the switch is activated to turn on the burner 17 and the fuel pump 30. The burner 17 thus ignites and heats the flame chamber 15 containing the boiler 18. The burner 17 is supported within a fire resistant fire pot 57 which is supported by a fire pot support 58. Burner 17 is holding tank 28
Recycled oils from or from external storage of conventional fuel oils can be burned. The recycle valve 51 and the conventional fuel oil valve 52 are manually opened and closed to select the fuel. The pump 30 is held in a water immersion tank 53 which is heated by an electric heating coil 54 to maintain the temperature in the immersion tank at about 165 ° F. Power to the in-line heater near the heating coil 54 and nozzle of the burner 17 is sufficient to process the inherent recycle oil of the equipment where the temperature of the fuel supply line, pump and burner has a higher viscosity than normal furnace fuel oil. It is supplied by an independent power source so that it remains high all the way. The fuel line pressure can be regulated by the pressure relief valve 56 and monitored by the pressure gauge 55. It has been found that operating pressures of 120 psi and 120 psi are desirable.

When the burner 17 and the fuel pump 30 are activated by the low level flow switch 72, the coil relay also automatically shuts off the supply pump 45 and closes the solenoid valve 43. Therefore, no further waste oil is supplied to the device for the time being. The waste oil already in the boiler 18 is gradually heated by the heat from the burner 17 until it reaches a distillation temperature of about 650 ° F. At this temperature, the lighter hydrocarbons are volatilized and pass through the discharge pipe 25 to the heat exchanger 26, while the sludge collects at the bottom 23 of the boiler 18 and gradually exits through the conduit 22. Volatilized lighter hydrocarbons are released and heat exchanger
Upon entering 26, the temperature of the heat exchanger 26 rises. Heat exchanger
The temperature increase of 26 indicates that the waste oil in the boiler 18 has reached the volatilization temperature. This is used as a signal to indicate that the device is ready for steady state operation. The thermocouple mounted in the middle of the heat exchanger 26 responds when the temperature reaches 130 ° F by activating the coil relays and is different in power to the burner 17 and fuel pump 30 for steady state operation. Transmit to the passage. This passage is blower 27
Includes a sail switch that will turn off power if the unit stops working for any reason. The thermocouple also opens solenoid valve 43 and starts feed pump 45 so that waste oil begins to flow from preheater 46 and into boiler 18 from feed storage tank 19. The oil level in the boiler 18 rises to the level preset by the float 70 in the float chamber 20. The float 70 controls the operating level in the boiler 18 by opening and closing the needle valve 44 so as to adjust the entire supply amount. Typically, the device operates in a stable condition of about 6-10 gallons / hour. Thermocouple or sludge removal on heat exchanger 26 turns on pump 66.

The holding tank 28 has a pan 50 underneath its top where the lighter condensed hydrocarbons collect. A second tube extends from this area and connects to the flame tube 32 so that the remaining uncondensed volatiles entering the holding tank 28 are sucked up with the flame tube gas. In operation, only fine traces of volatiles were found. Float switch in holding tank 28
29 activates an electric pump that drains a portion of the reclaimed liquid oil from the holding tank 28 to the external storage tank if the depth in the holding tank 28 exceeds the preset level.

The sludge passes from conduit 22 into process cooling tank 60 and then through heat exchanger 64 and solenoid valve 65 to sludge pump 66. The sludge pump 66 discharges the sludge to an external sludge storage tank at a rate of about 0.5 to 0.7 gallons / hour. Solenoid valve 65 directs flow through one of the two discharge branches. Solenoid valve 65 is biased to direct flow normally through a branch leading to sludge pump 66.
However, solenoid valve 65 may instead be actuated to direct flow to shutoff pump 67. "T" connects to the sludge discharge line between the process cooling tank 60 and the heat exchanger 64 and to the transfer tank 61 and hence to the float chamber.
Up to 20. The transfer tank 61 has an air release tube 62 with a valve 63 for releasing trapped air and is included to reduce heat transfer to the float chamber.

When the device is manually turned off, power to the feed pump 45 and sludge pump 66 is cut off and the solenoid valve 43
Is closed. However, the system will continue to operate until the oil level in the boiler 18 is reduced to the level of the low level float switch 72. At this point, the low level float switch shuts off power to burner 17 and fuel pump 30. The device is then cooled for about 2 hours. The temperature of the sludge in the conduit 22 immediately upstream of the process cooling tank 60 is 14
When cooled to 0 ° F, the thermocouple actuates solenoid valve 65 that closes the branch leading to sludge pump 66 and opens the branch leading to shutoff pump 67 and turns on shutoff pump 67.
The sludge and remaining oil is then completely drained from the system by the shutoff pump 67 to the external sludge storage tank. The sludge conduit immediately upstream from the first treatment cooling tank 60
When the temperature at 22 cools to 100 ° F, indicating the line is empty, the thermocouple reverses solenoid valve 65 and turns off the shutoff pump.

If the system runs out of waste oil or creates an interruption in the supply line, the oil level in the boiler 18 will be reduced to the level of the low level float switch 72. This is burner 17
And shut off power to fuel pump 30, turn off supply pump 45 and close solenoid valve 43. The device cools and is discharged in the manner previously described.

If disturbance occurs downstream, the oil in boiler 18 will reach the level of high level float switch 71. It also shuts off power to burner 17 and fuel pump 30, and turns off feed pump 45 and closes solenoid valve 43. Again, the device is cooled and then discharges itself.

High limit control in the flame chamber 15 and the heat exchanger 26 may also occur if the local temperature is accidentally added to the feed storage tank 19 with an unsuitable petroleum product, such as gasoline. If no preset limit is exceeded, the device will automatically shut off.

Example 1 This example illustrates the feasibility and efficiency of the present invention.

A prototype device, substantially similar to that shown in FIG. 1, with a pot burner was tested in the following procedure. A 25-gallon sample of a typical used Mortao obtained from an automotive service station was installed in a supply storage tank, float chamber and boiler. The unit was started using two cups (16 ounces) of conventional No. 1 fuel oil (kerosene). The flame chamber was heated to reach a boiler temperature of 650 ° F and the system was operated continuously for 24 hours. During operation, the unit consumed about 4.25 imperial gallons of waste oil / hour. This is about 0.75 imperial gallons /
The time generated about 150,000 BTU / hour due to heating and was consumed by the combustion in the flame chamber. Approximately 3.1 imperial gallons / hour of additional recycled oil were accumulated in the holding tank and approximately 0.4 imperial gallons / hour of sludge were accumulated in the sludge tank.

Example 2 This example further demonstrates the feasibility and efficiency of the present invention.

A prototype device substantially similar to that shown in FIG. 1 was tested under the conditions shown in Table I and by the same procedure as described in Example I. Chemical and physical analyzes were performed on waste oil feedstocks, recycled oils and sludges and the results are shown in Table II.

The yield of recycled oil was about 90%. The product compares favorably with commercial light fuel oils in terms of base composition and calorific value. However, the viscosity, pour point and flash point were significantly different from the corresponding values for commercial light fuels. This was due to a clear difference in composition. Commercial light fuels consist essentially of saturated paraffinic aliphatic hydrocarbons with a relatively narrow boiling range, while analysis of recycle oils has a very broad range of generally higher boiling points. It was shown to contain a mixture of saturated and unsaturated paraffinic aliphatic hydrocarbons. However, it should be noted that the cetane number of recycled oil was very high, about 56, compared to the typical range of 40-45 for diesel fuel in North America.

Of course, it will be appreciated that many variations of the device and method of the present invention are possible.

Table I Operating Conditions for Example 2 Time: Start to Recycled Oil Production Start = about 4 hours 35 gallons of recycled oil Production time = about 6 hours Total = 10 hours Production = about 3.6 gallons / hour Temperature: Production Inside boiler = 635 ° F (335 ° C) At the end of production boiler = 645 ° F (340 ° C) Stack during production = 595 ° F (313 ° C) Material balance: Waste oil Raw material oil amount = 40 gallons Total amount of oil used = 36 gallons Efficiency (percentage recovery of recycled oil) = 90% Amount of recycled oil burned to suppress operation = approx. 0.7 gallons / hour Sludge = 3 gallons Loss due to leakage and volatilization = approx. 1 gallon TD = too dark to observe ^{* The} ash is very high for the oil sample and the ash component is present as an oxide, which severely distorts the equation used to obtain the "oxygen by difference". ^** Pensche Martens Closed Cup

[Brief description of drawings]

1 is a schematic view showing an embodiment of the device of the present invention, FIG. 2 is a sectional side view showing another embodiment of the device of the present invention, and FIG. 3 is a line 3-3 of the device of FIG. It is a top view which shows one part along the plane shown by. In the figure, reference numeral 10 is a confinement structure, 11 is a first chamber, and 12 is a second chamber.
Chamber, 13 common wall, 14 opening, 15 flame chamber, 17 burner, 18
Is a boiler, 19 is a storage tank, 20 is a float chamber, 24 is a sludge tank, 26 is a heat exchanger, 27 is a blower, 40 is a float switch, 44 is a needle valve, 45 is a supply pump, and 66 is a sludge pump.

Claims (18)

[Claims] Claim: What is claimed is: 1. A waste oil recycling device for recycling useful oil products from waste oil, the oil supply means by which waste oil is supplied to the device; the waste oil fluidly connected to the oil supply means For heating waste oil in the boiler to a temperature at which lighter hydrocarbons of the waste oil volatilize but heavier hydrocarbons do not, thereby trapping contaminants with it. A first discharge conduit for lighter hydrocarbons that are fluidly connected to and volatilized to the boiler to separate heavy hydrocarbons that do not volatilize less volatile hydrocarbons and pollutants and for heavy hydrocarbons that do not volatilize A waste oil recycling device comprising a separation means including a second discharge conduit of 2. The heater comprises an oil burner fluidly connected to the separating means and adapted to receive and burn the lighter volatilized hydrocarbons from the separating means. The waste oil reuse device according to claim 1. 3. The waste oil reusing apparatus according to claim 2, wherein the separating means is provided by the boiler. 4. The boiler of claim 3, wherein in operation, the boiler is positioned above the oil burner at intervals such that the temperature of the boiler is in the range of about 600-800 ° F. Waste oil recycling equipment. 5. Further comprising: fluidly connected to said separation means and adapted to receive said lighter volatilized hydrocarbons from said separation means, and fluidly connected to said oil burner and to said il burner. A waste oil recycling device according to claim 4, characterized in that it comprises a condenser for condensing the volatilized lighter hydrocarbons, which is adapted to supply the recondensed lighter volatilized hydrocarbons. 6. The waste oil reusing apparatus according to claim 5, further comprising valve means for controlling a flow of waste oil from the oil supply means to the boiler. 7. A heavier hydrocarbon further comprising a recycle oil container fluidly connected to and between the condenser and the oil burner, and further fluidly connected to the separating means. And a sludge container adapted to receive the sludge product of contaminants. 8. The waste oil reuse device according to claim 7, wherein the valve means comprises a float chamber. 9. The condensing means comprises a heat exchange conduit having heat transfer fins extending outwardly therefrom, and further a blower means for blowing cooling air over the heat exchange conduit. 8. The waste oil reuse device according to item 8. 10. A substantially enclosed first chamber within which the float chamber, the heat exchange conduit and the blower means are located, and substantially enclosed within which the oil burner and the boiler are located. A confinement structure having an open second chamber, the first and second chambers being substantially separated by a common wall, but in fluid communication with each other through a vent in the common wall, And further, a heating conduit fluidly connected to the first chamber for releasing heated air, a fire chamber in which the oil burner is disposed, and a fire chamber for exhausting combustion smoke from the fire chamber. 10. A flame tube fluidly connected to the firebox.
The waste oil reuse device described in. 11. The boiler has a sloping base, the base comprising a barrier extending upwardly from the barrier, wherein the non-volatile heavy hydrocarbons flow around the barrier below the sloping base while volatilizing. 11. The waste oil recycling device according to claim 3, 4 or 10, wherein said lighter hydrocarbon is adapted to pass above the barrier. 12. The float chamber has a first operating level float operating on the valve means, a second low level float operating on the valve means and the oil burner, and on the valve means and the oil burner. 11. A waste oil recycling device as claimed in claim 8, 9 or 10 comprising a third high level float in operation. 13. Further extending between and fluidly connecting the recycle oil container and an upper portion of the flame tube for discharging non-condensable volatiles entering the recycle oil container. 11. The waste oil reuse device according to claim 10, which is composed of a pipe. 14. The oil burner is a gun-type burner with an in-line heater for heating its nozzle, and further from a hydraulic pump maintained in a water bath heated to feed the oil burner. 11. The waste oil reuse device according to claim 2, 5 or 10, wherein 15. The oil supply means includes a supply pump for supplying waste oil to the boiler in a substantially constant amount, and also permits the supply of additional waste oil to the boiler in a variable amount corresponding to the float chamber. 11. The waste oil reuse device according to claim 8, 9 or 10, wherein the waste oil reuse device comprises a needle valve. 16. A lighter hydrocarbon of waste oil is produced,
Heating the waste oil in a boiler to a temperature in the range of about 600-800 ° F such that the heavier hydrocarbons do not volatilize, thereby trapping contaminants with the heavier hydrocarbons, and then the lighter volatilized hydrocarbons. A method for treating waste oil, which comprises the step of separating volatile matter from heavier hydrocarbons and contaminants that have not volatilized. 17. A method according to claim 11, wherein the temperature is about 650 ° F. 18. The method further comprises the step of condensing the volatilized lighter hydrocarbons and combusting at least a portion of the condensed volatilized lighter hydrocarbons, the heat of combustion of which causes the waste oil to be burned in the boiler. The method for treating waste oil according to claim 16, which is used for heating.