Retrofit waste vault system

A retrofit system for biological treatment sanitation vaults wherein evaporation of the liquid waste is accelerated by locating a conduit within the waste receptacle into which only liquid may flow and evaporate within the conduit in the air flowing therethrough. A double conduit system substantially connected in parallel may be used to evaporate liquids accumulating in vaults receiving heavy use for short durations as a float operated air control system permits the most effective utilization of the air movement through the conduit circuit as automatically controlled by the liquid level.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention pertains to a biological waste treating system accelerating 
the evaporation of liquids which may be retrofitted to existing waste 
receptacles. 
2. Description of the Related Art 
Biological waste treatment systems such as found in biological composting 
toilets are known wherein the apparatus of the waste treating system 
exposes the waste, which includes liquid and solid matter, to air to 
accelerate evaporation and decomposition. A number of patents directed to 
such biological treatment systems are shown in U.S. Pat. Nos. 1,567,414; 
3,136,608; 3,624,665; 3,808,609; 4,096,592; 4,313,234 and 4,343,051. Also, 
in my Patent 5,342,516, a biological waste conversion system is shown 
wherein the evaporation of the liquid within the waste matter is 
accelerated by exposure of the liquid to air flow. 
While existing apparatus accelerates the evaporation of liquid and 
decomposition of the solid waste, known biological waste treatment systems 
require specially constructed waste receiving vaults and containers, and 
the prior art apparatus is not suitable for use with existing waste 
receiving receptacles or vaults. As a great number of pre-existing 
receptacles and vaults are presently in use, it is highly desirable to 
utilize present technology to improve the decomposition and treatment of 
waste in such vaults but apparatus for doing so has not heretofore been 
available. 
OBJECTS OF THE INVENTION 
It is an object of the invention to provide a biological waste treatment 
system which may be retrofitted to existing waste receptacles and vaults 
to accelerate the evaporation of liquids therefrom. 
Another object of the invention is to provide a retrofitable liquid 
evaporation system for existing waste receiving vaults which is of 
economical construction and may be readily installed without requiring 
exceptional skills. 
Yet another object of the invention is to provide a waste treatment system 
for evaporating liquids from a waste receiving vault wherein the 
efficiency of evaporation of the system is not adversely affected under 
temporary high usage conditions and the evaporation system accommodates 
itself to the volume of liquid within the vault. 
SUMMARY OF THE INVENTION 
In the practice of the invention, an airflow conduit system is retrofitted 
within a conventional waste receiving vault. The conduit system includes 
an evaporation portion preferably substantially horizontally disposed 
which is located adjacent the bottom of the vault and the conduit system 
includes inlet and outlet portions whereby air may travel through the 
system. 
The evaporation portion includes a filter whereby liquids within the vault 
may flow into the conduit evaporation portion, the solids being excluded, 
and the flow of air through the conduit system evaporates the liquid 
therein. Preferably, the outlet portion of the conduit system includes a 
vertically oriented stack inducing the flow of air through the system as 
entering the inlet portion, and in the preferred arrangement, an electric 
blower or fan is located in the stack to insure a rapid flow of air 
through the conduit system to rapidly evaporate the liquid therein. 
In vaults periodically subjected to high usage wherein the liquid 
accumulation may be greater than the ability of the evaporation system to 
handle the liquid, a plurality of evaporation portions may be included in 
the conduit system vertically related to each other so as to handle 
temporary high usage conditions. In such event, liquid level float 
operated gates are located within the upper evaporation portions which 
automatically open as the liquid level increases, and close as the liquid 
level falls. The use of such float operated control gates assures high 
efficiency of operation in that maximum air flow takes place through the 
evaporation portion which is not "flooded" closed, and as the liquid level 
falls, the upper evaporation portions are closed to air flow so that the 
liquid level of the waste is reduced to its minimum depth.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The retrofitable biological waste treatment system constituting the 
invention will normally be employed in restroom and toilet facilities 
usually located in remote areas wherein sewers and septic tank systems are 
not available. Such facilities may include a roofed building 10, FIG. 1, 
having a vault or lower compartment 12 which may be of concrete, steel, 
glass fibre or plastic and is usually buried in the ground. The building 
10 includes the floor 14 which constitutes the top of the vault and a 
toilet stool 16 located within the building 10 upon floor 14 permits waste 
to enter the vault 12. As shown in FIGS. 1 and 2, the vault 12 includes a 
receptacle 18 for receiving the waste, and it is to be appreciated that 
the receptacle 18 is optional as the vault 12 also constitutes a waste 
receptacle and is so designated in the following description and claims. 
An access door 19 permits the receptacle 18 to be periodically cleaned, and 
the receptacle 18 includes a bottom 20, vertically oriented sides 22 and 
an open top 24 whereby the waste enters the receptacle. 
The invention includes a conduit system 26 located within the receptacle 
18. The conduit system 26 may be formed of synthetic plastic or metal 
tubular conduits and includes a substantially horizontal evaporation 
portion 28, an inlet portion 30 which communicates with the evaporation 
portion 28 and an outlet portion 32 also communicating with the portion 
28. A ventilation inducing tubular stack 34 is in communication with the 
outlet portion 32, and an electric blower or fan 36 is preferably mounted 
upon the upper end of the stack 34 and may be powered by an electric 
utility power line, or a battery system charged by a solar panel mounted 
upon the roof of the building 10. 
The conduit system evaporation portion 28 preferably rests upon the 
receptacle bottom 20, and straight portions of the evaporation portion 28 
include a plurality of holes 38, FIG. 1, whereby liquid within the 
receptacle 18 may enter the evaporation portion 28. To prevent solid waste 
from entering the evaporation portion 28, and to prevent clogging of the 
holes 38, a filter mesh 40 of a synthetic plastic type having small 
openings surrounds the evaporation portion in which the holes 38 are 
formed. This mesh may consist of a fiber material sold under the trademark 
Ceotextile. The evaporation portion 28 includes elbows 42 which permit the 
air flowing through the conduit system 26 to pass through a circuitous 
system located in the receptacle 18. 
In use, liquid and solid waste enters the receptacle 18 through the stool 
16. The liquid within the receptacle will pass through the mesh filter 40 
and the holes 38 into the horizontal evaporation portion 28 of the conduit 
system 26. While the stack 34, alone, will produce a flow of air through 
the conduit system 26 under certain temperature conditions, energizing of 
the fan 36 will produce a strong flow of air through the conduit system 26 
wherein the air will enter the inlet portion 30 as indicated by the 
arrows, the opening of the inlet portion 30 being located within the vault 
12, and after the air has flowed through the evaporation portion 28 and is 
exposed to the liquid within the horizontal evaporation portion 28 
evaporating the liquid, the air and vapor will pass out the outlet portion 
32 through the stack 34 and fan 36 to the atmosphere. 
The rapid flow of air through the conduit system 26 will rapidly evaporate 
liquid from the receptacle 18 permitting the dry solid material to 
biologically decompose, and it is only necessary to clean the solid 
material from the receptacle 18 through the access door 19 at widely 
spaced intervals. 
Of course, with the embodiment shown in FIG. 2, the most effective 
operation of the system occurs when the liquid level within the horizontal 
evaporation portion 28 is less than three-quarters the vertical height of 
the evaporation portion conduits. There must be enough air flow passage 
within the evaporation portion conduits to permit air to flow 
therethrough. As the liquid is evaporated from the receptacle 18, the 
liquid level diminishes, and under normal operating conditions, the liquid 
level within the receptacle 18 is only an inch or two and a high rate of 
air flow through the conduits system 26 is possible. 
The conduit system 26, by the use of linear portions and the elbows 42, may 
be easily retrofitted to existing vaults and receptacles, and as the 
conduit system is assembled of a plurality of linear and elbow parts, a 
conduit system of the configuration most apropos to the configuration of 
the associated receptacle is possible. In the practice of the invention, 
the liquid level within the receptacle 18 is minimized permitting optimum 
biological decomposition of the solid waste. Toilet facilities utilizing 
the concepts of the invention require very little maintenance and the 
receptacles only need to be cleaned on a six month or one year cycle. 
An embodiment utilizing the inventive concepts is illustrated in FIGS. 3 
and 4 wherein the apparatus is capable of handling short duration high 
volume usage. In the embodiment of FIGS. 3 and 4, cessation of air flow 
through the conduit system due to "flooding" is prevented and an air flow 
control system is employed regulated by the level of the liquid within the 
vault. 
In the embodiment of FIGS. 3 and 4, the receptacle or vault is indicated at 
44. The receptacle 44 is usually buried in the ground and a building, not 
shown, will be erected above the receptacle. The receptacle includes a 
bottom 46, vertically oriented sides 48 and a top 50 which serves as the 
floor of the building, not shown. Waste enters the receptacle 44 through a 
toilet stool, urine troughs and the like, not shown, and access to the 
receptacle 44 is through manhole 52. 
The conduit system within the receptacle 44 is generally indicated at 54 
and includes horizontally disposed lower evaporation portion 56 and upper 
evaporation portion 58. As illustrated, the upper portion 58 is mounted 
upon the lower portion 56. An inlet portion conduit 60 having an open end 
62 is located within the receptacle 44 and communicates with both 
evaporating portions 56 and 58. In a like manner, the conduit system 
outlet portion 64 communicates with both the lower and upper evaporation 
portions. A stack portion 66 is in communication with the outlet portion 
64, and a vertically oriented stack and electric motor, not shown, may be 
incorporated into the stack portion 66 as it extends vertically to the 
atmosphere. 
The evaporation portions 56 and 58 are provided with holes surrounded by 
filter mesh 68 and 70, respectively, and the evaporation portions include 
elbows 72 similar to the previously described embodiment. 
The upper evaporation portion 58 includes straight or linear portions 74 
and gates 76 are located within the portions 74. The gates 76 are capable 
of vertical adjustment relative to the associated portions 74 wherein 
raising of the gates 76 permits air flow through the upper evaporation 
portion 58, while lowering of the gates 76 prevents air flow through the 
upper evaporation portion 58. Vertical positioning of the gates 76 is by 
means of the floats 78 attached to the gates wherein as the liquid within 
the receptacle 44 increases, the liquid level will engage the floats 78 
raising the gates 76 permitting air flow through portion 58, while as the 
liquid level descends, the floats 78 will descend therewith lowering the 
gates 76 and prevent air flow through the evaporation portion 58. 
In use, air will flow through the conduit system 54 as indicated by the 
arrows due to induced air flow through the stack system, or operation of 
an electric fan, not shown. When liquid within the receptacle 44 of a 
depth less than the vertical height of the lower evaporation portion 56 it 
will flow into the portion 56 and be evaporated by the air flow thereover. 
Because the liquid level within receptacle 44 is less than the vertical 
height of the portion 56, the floats 78 and gates 76 will be in their 
lowermost position as shown in FIG. 3 and air flow through the upper 
evaporation portion 58 is prevented. 
Under high usage conditions, the liquid level within the receptacle 44 may 
temporarily rise above the vertical height of the lower evaporation 
portion 56 which causes the portion 56 to "flood" preventing air flow 
therethrough. Such an elevation in the liquid level will cause the floats 
78 to lift the gates 76 permitting air flow through the upper evaporation 
portion 58 so that air may flow through the portion 58 and evaporate the 
liquid therein. As the liquid level descends, the gates 76 will 
automatically descend, and the floats 78 will be so positioned relative to 
the gates 76 that the liquid level will be lower than the upper most 
portion of the evaporation portion 56 so that air flow through portion 56 
is possible before the gates 76 completely close and now shunt all of the 
air flow through conduit system 54 through the lower evaporation portion 
56. 
The aforedescribed automatic operation of the air flow through the conduit 
system 54 permits large temporary usage while still maintaining the 
efficiency and advantages of the invention. 
As with the embodiment of FIGS. 1 and 2, the conduit system shown in FIGS. 
3 and 4 may be readily retrofitted to existing biological waste systems, 
and of course, the conduit systems of both embodiments may also be 
installed in new units. 
It is appreciated that various modifications to the inventive concepts may 
be apparent to those skilled in the art without departing from the spirit 
and scope of the invention.