Raw sewage disposal apparatus

A raw sewage disposal apparatus, such as a portable toilet. The apparatus has a vessel with a first introduction pipe for feeding raw sewage into the vessel. The vessel is externally heated and contains heat holding bodies and an agitator so that the sewage can be heated to evaporate liquid therefrom while being agitated to break down nonevaporable substances into powder. A second introduction pipe is provided to circulate air through the vessel to remove the vapor and later the power therefrom. A deodorizing means including a catalyst, and a preheater for preheating the catalyst, are provided to treat the vapor to make it substantially odorless. A third introduction pipe is provided for supplying fresh air to the preheater. A dust collector is provided to collect the powder.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a raw sewage disposal apparatus for 
disposing of raw sewage, which apparatus can be utilized in the outdoors, 
in a transportation means, such as a vessel or train, or in a tunnel 
through which a tank truck used for collecting raw sewage (hereinafter 
referred to as a vacuum truck) cannot go and, more particularly, to an 
apparatus provided with a dust collector capable of removing the dust that 
remains in the apparatus after drying the raw sewage and a heating means 
for heating catalyst means, said apparatus being capable of withstanding 
long use and facilitating maintenance and inspection thereof. 
2. Description of the Prior Art 
The raw sewage discharged from a human body is typically discharged into a 
sewage system by use of a flush toilet and the like, and thence into a 
river, after being temporarily stored in a holding tank and purified 
therein. However, at events, such as festivals, athletic events, fairs, 
meetings and the like, temporary toilet facilities must be provided to 
dispose of raw sewage. 
Employed conventionally are movable (portable) temporary toilets, most of 
which have a tank for temporarily storing the raw sewage therein. However, 
the temporary toilets have a problem in that the raw sewage stored in the 
tank is sucked into a vacuum truck for collection, which is laborious and 
maintenance of them, after they are used, is time consuming and is 
nonhygienic. 
Transportation vehicles, such as buses, trains, vessels, etc. which operate 
over long distances are provided with a tank exclusively used for storing 
and holding the raw sewage. The raw sewage in this tank is subjected to a 
deodorizing treatment by chemicals, and thereafter is collected by a 
vacuum truck. 
As mentioned above, the raw sewage in the conventional temporary toilets or 
the movable transportation facilities is at first stored as it is 
discharged from the human body and then is collected thereafter. 
Accordingly, the storing method, the collection method and the disposal 
method all are not modern and very nonhygienic. 
In an attempt to ameliorate the above problems, there have been proposed 
several hygienic disposal methods. In one method, for example, chemicals 
are introduced into the tank where the raw sewage is stored to thereby 
prevent the bad smell and to effect sterilization of the raw sewage. This 
is mainly employed in the transportation industry, such as on trains like 
the Shinkansen Express in Japan. This method, however, cannot be used for 
a long period of time because the chemicals become diluted and the costs 
are high. 
In another method, the raw sewage is stored in a bag made of vinyl and the 
like to prevent diffusion of the bad smell. This method, however, requires 
a vinyl bag of large size and involves high cost for disposal thereof, and 
it is troublesome to separate the raw sewage from the bag. 
In still another method, the discharged raw sewage is directly dried by use 
of heat from a burner, etc. Since the primary component of raw sewage is 
liquid, a large amount of heat energy is required to remove the liquid and 
it takes a long time to effect disposal of the raw sewage. 
In view of the drawbacks of the conventional methods for disposing of raw 
sewage, the present inventor proposed a drying apparatus having a casing 
provided with stirring blades and heat holding bodies therein in which the 
raw sewage is stirred by the rotation of the stirring blades and heated by 
heat generated by the heat holding bodies whereby the raw sewage is dried 
in a short period of time. This is disclosed in Japanese Patent Laid-Open 
Publication Nos. 63-124150, 63-172852, 63-190857, 63-292789 and 
Application No. 63-198858, corresponding to U.S. patent application Ser. 
No. 351,029, filed May 12, 1989, now U.S. Pat. No. 4,999,930, issued Mar. 
19, 1991. Another related application is U.S. Ser. No. 575,910, filed Aug. 
29, 1990. According to the proposed disposal methods, the raw sewage is 
heated in a casing and the liquid component of the raw sewage is vaporized 
and diffused into the ambieht atmosphere. Before the vaporized liquid 
component is diffused, components which cause a bad smell are treated by 
the catalyst and then the vaporized liquid component is diffused into the 
atmosphere as an odorless vapor. It is preferable to employ such a method 
in view of environmental hygiene and preservation even if such method is 
employed around crowded buildings and occasions having throngs of people. 
The elimination of the bad smell has been effected in an airtight casing. 
In the airtight casing, nonflammable residual substances, which are small 
portions of the total liquid component, remain in the casing, although 
most of the liquid component can be vaporized. It was necessary to remove 
the residual substances or dusts present in the casing. To remove such 
residual substances and clean the casing, the casing was disassembled so 
that the inside of the casing was exposed. There was a problem in that it 
was laborious to disassemble, clean and reassemble the casing, and the 
temporary toilet could not be used while the casing was undergoing 
disassembly, cleaning and assembly operations. 
Furthermore, it was necessary that the vapor should pass through the 
catalyst to eliminate the odor-causing substances, such as ammonia, urea 
and the like, which are generated during heating of the liquid component 
of the raw sewage. Bad smell generating components were subjected to 
oxidation-reduction and were thereby rendered odorless and then they were 
diffused in the atmosphere. As the catalyst, precious metals, such as 
platinum, have been typically employed. Such a catalyst should be always 
kept at a constant temperature exceeding a predetermined value for 
subjecting the bad smell generating components to oxidation-reduction. In 
my companion application U.S. Ser. No. 07/784595 corresponding to 
Japanese-Serial Nos. 164594/90, 411577/90, 67538/91 and 189280/91, a 
secondary heater is disposed in a passage between an evaporation cauldron 
and the catalyst means and always heats the catalyst to keep the 
temperature of the catalyst constant. When the temperature of the vapor 
evaporated from the evaporation cauldron is reduced during the flow 
thereof and contacts the catalyst at such a lower temperature, the 
catalyst cannot effectively perform the oxidation-reduction. Accordingly, 
the vapor evaporated from the evaporation cauldron is reheated by the 
secondary heater, its temperature is increased and thereafter it contacts 
the catalyst. 
If the vapor, including ammonia and urea, directly contacts the secondary 
heater, the secondary heater is oxidized by the components of the vapor 
which causes breakage and erosion of the secondary heater. These 
disadvantages are not desired because they increase the required 
maintenance of the heater. It is necessary that the secondary heater can 
be used for a long time. 
SUMMARY OF THE INVENTION 
It is a first object of the present invention to provide a raw sewage 
disposal apparatus capable of eliminating residual substances and cleaning 
the casing without disassembling the casing. 
It is a second object of the present invention to provide a raw sewage 
disposal apparatus capable of preventing the secondary heater from being 
oxidized or deteriorated by the components of the vapor and assuring that 
the secondary heater can be used for a long time. 
A first aspect of the present invention provides a raw sewage disposal 
apparatus comprising a heat-resistant casing for containing raw sewage, a 
heating means for heating the casing, a drive means provided over the 
casing and having a stirring means fixed thereto and extending into the 
casing, a plurality of heat holding bodies which are heated and contained 
in the casing, an air introduction pipe connected to a part of the casing 
for introducing fresh air into the casing, an air discharge pipe connected 
at one end thereof to a part of the casing for discharging air from the 
casing, a cyclone dust collector connected to another end of the discharge 
pipe for separating air from the dust and a catalyst means connected to 
the discharge pipe. 
A second aspect of the present invention provides a raw sewage disposal 
apparatus comprising a heat-resistant casing for storing raw sewage, a 
heating means for heating the casing, a drive means provided over the 
casing and having a stirring means fixed thereto and extending into the 
casing, a plurality of heat holding bodies which are heated and contained 
in the casing, an air introduction pipe connected to a part of the casing 
for introducing fresh air into the casing, an air discharge pipe connected 
at one end thereof to a part of the casing for discharging air from the 
casing, a cyclone dust collector connected to another end of the discharge 
pipe for separating air from the dust, a reheating means including a 
secondary heater connected to the air introduction pipe, an ejector 
connected at one end to an output of the secondary heater means for 
generating negative pressure and connected at the other end to the 
catalyst means and a bypass path having a closing valve and provided 
between a negative pressure side of the ejector and the discharge pipe.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
First Embodiment (FIGS. 1 to 6) 
A raw sewage disposal apparatus according to a first embodiment will be 
described with reference to FIGS. 1 to 6. 
The raw sewage disposal apparatus can be suspended by a crane and the like 
and is movable by a truck and the like. 
The raw sewage disposal apparatus (hereinafter referred to simply as the 
apparatus) has the external shape of a cube, it is formed by bending a 
steel plate and its interior is hollow. The apparatus 1 can carry out a 
series of raw sewage processing steps, such as storing, evaporating and 
deodorizing of the liquid component of the raw sewage. The apparatus 1 
comprises a single unit which can be conveyed to a construction site, a 
sports event and the like and operated independently. 
The apparatus 1 has a stool 2 at one side thereof for receiving urine 
discharged from the human body. An introduction pipe 3 is connected at one 
end thereof to the lower side of the stool 2 and at the other end thereof 
to a liquid evaporator 11, to be described later. A plurality of vents 5 
and 6 are defined on side surfaces of the apparatus 1 at the upper and 
lower portions thereof for ventilation of the interior thereof. Hooks 7 
are fixed to the upper surface thereof at the four corners thereof so that 
the apparatus 1 can be hung by a crane and can be moved to the appropriate 
location. 
The apparatus 1 comprises the cylindrical liquid evaporator 11, a 
cylindrical collection box 12 connected to the liquid evaporator 11 by 
means of a discharge pipe 15, a cyclone dust collector 13 (hereinafter 
referred to as simply dust collector) disposed over the collection box 12 
and a deodorizing unit 14. An air blower 16 is disposed in association 
with the liquid evaporator 11 and an air introduction pipe 17 is connected 
to the air blower 16. The air introduction pipe 17 is branched to provide 
a first pipe connected to a first control valve 18 and a second pipe 
connected to a second control valve 19. The first control valve 18 is 
connected to a cleaning pipe 20 which in turn is connected to the liquid 
evaporator 11 while the second control valve 19 is connected to a 
preheating pipe 21 which in turn is connected to the deodorizing unit 14. 
Referring to FIG. 3, a tank chamber 25 is provided in the middle portion of 
the introduction pipe 3 for storing overflow liquid in said chamber. The 
tank chamber 25 has a liquid sensor 26 therein for detecting the overflow 
of the liquid. A third control valve 27 is provided in the pipe 3 between 
the tank chamber 25 and the liquid evaporator 11. 
The liquid evaporator 11 has an evaporation cauldron 28 at the lower half 
thereof. The cauldron 28 is formed of a heat-resistant material, such as 
stainless steel and the like. The evaporation cauldron 28 is connected to 
the introduction pipe 3 at the central side surface thereof and is 
connected to the discharge pipe 15 at the upper side surface thereof. 
Heating coils 29 are wound around the side surfaces and the bottom of the 
evaporation cauldron 28. A heat insulating member 30 surrounds the heating 
coils 29 at the periphery of the evaporator cauldron 28 for preventing 
heat from dissipating outside the evaporation cauldron 28. A temperature 
sensor 63 is embedded in the heat insulting material at a location close 
to the side surface of the evaporation cauldron 28 for detecting the 
temperature in the evaporation cauldron 28. A drain pipe 31 is connected 
to the bottom of the evaporation cauldron 28. A cock 32 is attached to the 
drain pipe 31 for temporarily discharging urine stored in the evaporation 
cauldron 28. 
A cylindrical joint portion 35 is attached to an upper portion of the 
evaporation cauldron 28. A motor retainer 36 having a closed upper end and 
an open lower end covers the upper portion of the joint portion 35. With 
such an arrangement, the inside of the evaporation cauldron 28 is 
hermetically sealed from the outside. Bearings 37 and 38 are provided at 
the upper and lower portions of the joint portion 35 for rotatably 
supporting a vertical rotary shaft 39. The rotary shaft 39 is elongated 
and cylindrical and extends to a location close to the bottom of the 
evaporation cauldron 28. The rotary shaft 39 has stirring blades 40 fixed 
to the lower circumference thereof at two diametrically opposed portions 
thereof. A plurality of freely and independently movable heat holding 
bodies 41 are placed in the evaporation cauldron 28 and are movable 
therein by rotation of the stirring blades 40. The heat holding bodies 21 
are made of a high heat holding material, such as alumina (Al.sub.2 
O.sub.3), pumice and the like. 
A motor 42 is fixed to the upper surface of the motor retainer 36 and has 
an output shaft 43 which extends inside the motor retainer 36 and is 
connected to the upper end of the rotary shaft 39 by means of a joint 44. 
With this arrangement, the output of the motor 42 is transmitted to the 
rotary shaft 39 by means of the output shaft 43, thereby rotating the 
stirring blades 40 inside the evaporation cauldron 28. 
Housed in the air blower 16 are a motor 47 and a fan 48, which is rotated 
by the motor 47. One of the branches of the air introduction pipe 17 is 
connected to the cleaning pipe 20 by way of the first control valve 18. 
The tip end of the cleaning pipe 20 enters inside the evaporation cauldron 
28 by way of the joint portion 35 and forms a nozzle 49 directed toward 
the bottom of the evaporation cauldron 28. The other branch of the air 
introduction pipe 17 is connected to the preheating pipe 21 by way of the 
second control valve 19. The tip end of the preheating pipe 21 is 
connected to the lower portion of the deodorizing unit 14. 
The tip end of the discharge pipe 15 is connected to the side surface of 
the dust collector 13. The dust collector 13 is connected to the collector 
box 12 which temporarily stores only the dust that has been separated from 
the air. The collector box 12 has a metallic dust box 50 on the inside 
thereof. The dust box 50 has an open upper end and a closed lower end 
forming the bottom thereof. A heater 51 is wound around the periphery of 
the dust box 50. Both the heater 51 and the dust box 50 are surrounded by 
a heat-insulating material 52 for preventing the heat from dissipating 
outside the dust box 50. A cover 53 is brought into contact with the upper 
open end of the dust box 50 for closing same. The lower open end of the 
dust collector 13 is connected to the cover 53. A vertical separation pipe 
54 is provided in the dust collector 13 at the central portion thereof for 
flowing the separated air, alone, upwardly therethrough. The tip end of 
the separation pipe 54 is connected to the bottom of the deodorizing unit 
14. 
The deodorizing unit 14 oxidizes the bad smell components, such as ammonia, 
urea and bromine, contained in the discharged vapor, thereby eliminating 
the bad smell. The deodorizing unit 14 is cylindrical and hollow inside 
thereof and has a secondary heater 57 at the lower portion thereof. The 
deodorizing unit 14 further includes a honeycomb catalyst bed 58 which 
fills the middle portion thereof and is disposed above the secondary 
heater 57. Rectifier plates 59 and 60 are provided above and below the 
upper and lower ends of the catalyst 58. An L-shaped duct 61 is attached 
to the upper portion of the deodorizing unit 14 for diffusing air outside 
the deodorizing unit 14. 
The detailed structure of the evaporation cauldron 28, the joint portion 35 
and the motor retainer 36 is illustrated in FIG. 4. 
FIG. 5 shows a circuit diagram of the control system of the first 
embodiment. 
An input circuit 66 for receiving control signals has its input terminals 
connected to a main switch 64, an evaporation switch 65 and a liquid level 
sensor 26 and its output terminal is connected to a control circuit 67. An 
input terminal of the control circuit 67 is connected to a temperature 
sensor 63 and its output terminals are connected to a standby operation 
circuit 68, a valve operation circuit 69, a dry operation circuit 70 and a 
lamp or a press button 8 for indicating nonuse of the apparatus 1. 
The output terminals of the standby operation circuit 68 are connected to 
the secondary heater 57 and the motor 47 of the air blower 16. The output 
terminals of the valve operation circuit 69 are connected to the first, 
second and third control valves 18, 19, 27. The output terminals of the 
dry operation circuit 70 are connected to an inverter circuit 72, the 
motor 42 and the heaters 29 and 51. An output terminal of the inverter 
circuit 72 is connected to the motor 47. 
The operation of the raw sewage disposal apparatus, according to the first 
embodiment of the present invention, will be described hereinafter. 
The apparatus 1 should be in standby status before operation thereof. 
The main switch 64 is pressed to give instruction to the control circuit 67 
for operating the apparatus 1. 
The control circuit 67, upon reception of the instruction from the main 
switch 64, issues a signal to the standby operation circuit 68 so that the 
secondary heater 57 is energized and the motor 47 is driven. At the same 
time, the control circuit 67 issues a signal to the valve operation 
circuit 69 for opening the second control valve 19 and closing the first 
control valve 18 and the third control valve 27. If the press button 71 is 
operated at the time when the stool 2 is used, the third control valve 27 
is opened for a short period of time so that urine can flow into the 
cauldron 28. 
In this state, air is supplied by the fan 48, which is rotated by the motor 
47, into the deodorizing unit 14 by way of the air introduction pipe 17 
and the preheat pipe 21. Hot air generated by the secondary heater 57 
flows toward the catalyst 58 together with air from the preheat pipe 21 to 
thereby heat the catalyst 58 when the same air is supplied into the 
deodorizing unit 14. At this time, the motor 47 is rotated at a low speed. 
The catalyst 58 is heated because the catalyst 58, such as platinum and 
the like, does not subject ammonia, bromine and the like to oxidation 
unless the catalyst is maintained at a temperature exceeding a 
predetermined temperature. When ammonia, bromine and the like pass through 
the catalyst at a low temperature, air having a bad smell is diffused from 
the duct 61. To prevent the bad smell from diffusing from the duct 61, air 
is supplied from the air blower 16 to the deodorizing unit 14 through the 
preheat pipe 21 so that the catalyst 58 is always kept warm and in standby 
status. 
The third control valve 27 is temporarily opened when the presser button 71 
(or the evaporation switch 65) is pressed in case of using the stool 2 so 
that the urine discharged into the stool 2 is introduced into the 
evaporation cauldron 28 by way of the introduction pipe 3. 
Since the first control valve 18 is closed, air from the air blower 16 does 
not flow into the evaporation cauldron 28 so that the bad smell from the 
evaporation cauldron 28 is not diffused outside from the introduction pipe 
3. 
The cock 32 connected to the evaporation cauldron 28 is manually closed. 
The cock 32 is opened when the urine present in the evaporation cauldron 
28 is discharged in case of improper operation of the apparatus 1. The 
cock 32 is not used normally. 
Use of the apparatus in the standby state is made first by discharging the 
urine into the stool 2. The urine received in the stool 2 is introduced 
into the evaporation cauldron 28 and stored successively in the 
evaporation cauldron 28. 
When the amount of urine stored in the evaporation cauldron 28 exceeds a 
predetermined amount, the thus-stored urine should be processed. The 
process is started by pressing the evaporation switch 65 (or the press 
button 71) for instructing the input circuit 66 to dry the urine. Although 
the evaporation switch 65 (or the press button 71) is manually pressed 
according to the first embodiment, an evaporation operation signal may 
also be supplied into the control circuit 67, by way of the input circuit 
66, by means of a timer which supplies a signal for starting the 
evaporation operation at fixed time intervals, for example, hourly. Also, 
an infrared ray sensor can be provided at the front surface of the stool 2 
for counting the number of uses of the stool 2 whereby the evaporation 
operation instruction is supplied into the input circuit 66 in case the 
actually counted number exceeds a preselected number. 
When the evaporation switch 65 is pressed or the evaporation operation 
signal is given in some different way, the evaporation operation signal is 
supplied to the control circuit 67 by way of the input circuit 66. At this 
time, the secondary heater 57 and the motor 47 operate in the same way as 
they operate before the evaporation operation signal is issued. However, 
the evaporation operation signal is supplied from the control circuit 67 
to the valve operation circuit 69 and the dry operation circuit 70. 
The valve operation circuit 69, upon reception of the evaporation operation 
signal, opens the first control valve 18 and closes the second control 
valve 19 and the third control valve 27. Air flowing into the preheat pipe 
21 is switched to the cleaning pipe 20 and is introduced into the 
evaporation cauldron 28 through the nozzle 49. Air is introduced into the 
upper end of the evaporation cauldron 28 for pushing vapor remaining in 
the evaporation cauldron 28 out of the evaporation cauldron 28 and 
facilitating the oxidation of the vapor. The third control valve 27 is 
closed for preventing the bad smell in the vapor from flowing out of the 
stool 2 by way of the introduction pipe 3. At the same time, the 
evaporation operation circuit 70 actuates the motor 42 and energizes the 
heaters 29 and 51. 
When the heater 29 is energized, the heater generates heat to heat the 
evaporation cauldron 28 from the outside of the evaporation cauldron 28 to 
evaporate the stored urine. 
When the motor 42 is actuated, the rotation of the output shaft 43 is 
transmitted to the rotary shaft 39 by way of a coupling 44 whereby the 
rotary shaft 39 and the stirring blades 40 ar rotated. By the rotation of 
the stirring blades 40, the heat holding bodies 41 accommodated in the 
evaporation cauldron 28 are simultaneously agitated in order to stir the 
urine stored in the evaporation cauldron 28 so that the temperature of the 
urine rises uniformly. Since the heat holding bodies 41 store the heat 
from the heater 29, the urine is mixed with the heat holding bodies 41 and 
contacts the surfaces of the heat holding bodies 41 so that the heat of 
the heat holding bodies 41 is smoothly transmitted to the urine to 
expedite the rise of the temperature of the urine. 
The urine in the evaporation cauldron 28, heated by the heater 29, starts 
evaporation when the temperature exceeds a given value. Inasmuch as the 
fresh air is supplied from the atmosphere through the cleaning pipe 20 and 
is introduced successively into the evaporation cauldron 28 through the 
nozzle 49, the vapor formed in the evaporation cauldron flows toward the 
dust collector 13 through the discharge pipe 15. The air including the 
vapor introduced into the dust collector 13 flows toward the deodorizing 
unit 14 by way of the separation pipe 54 (at this time, the air is jetted 
gently from the nozzle 49 so that a cyclonic flow of the air is not 
generated in the dust collector 13 whereby a fully effective dust 
separation operation does not yet occur). 
Since the secondary heater 57 is heated as set forth above, the vapor 
including the bad smell component is reheated and flows toward the 
catalyst 58. The hot vapor reheated by the heater 57 contacts the catalyst 
58, such as platinum, whereby the bad smell components, such as ammonia 
and bromine, are oxidized and become odorless and then are discharged 
outside from the duct 61. With the continuance of these operations, the 
vaporizable component of the urine in the evaporation cauldron 28 is 
successively evaporated, rendered odorless and is discharged outside. 
When urine is discharged from the stool 2 while the third closing valve 27 
remains closed, the urine is temporarily stored in the tank chamber 25. 
When the tank chamber 25 is filled with the urine, the liquid level sensor 
26 is actuated to thereby supply a signal indicating that there is no 
capacity to store more liquid. The signal is supplied to the input circuit 
66. When the signal is supplied to both the input circuit 66 and the 
control circuit 67, the lamp 8 provided at the front portion of the 
apparatus 1 is lighted to inform the user that the apparatus 1 is not 
usable at present. 
When the evaporation operation continues for a predetermined time, the 
vaporizable component of the urine stored in the evaporation cauldron 28 
is completely evaporated. The residual substances, such as waste matter 
and ash, which are not evaporated with the liquid component, remain in the 
cauldron in the form of powder. Since the heat holding bodies 41 are 
agitated by the stirring blades 40 the nonevaporable components are 
crushed into a fine powder. When the liquid component no longer remains in 
the evaporation cauldron 28, the temperature of the evaporation cauldron 
28 rises sharply. The temperature sensor 63 detects the sharp rise of the 
temperature of the evaporation cauldron 28 and informs the control circuit 
67 that no liquid component remains in the evaporation cauldron 28. The 
cleaning operation starts when the temperature sensor 63 detects the sharp 
rise of the temperature of the evaporation cauldron 28. 
The standby operation circuit 68 stops supplying a low speed signal to the 
motor 47 while at the same time the dry circuit 70 supplies a signal to 
the inverter circuit 72 and also supplies a high speed signal to the motor 
47. The rpm of the motor 47, upon reception of the high speed signal, is 
increased compared with that in the drying operation so that the motor 47 
rotates the fan 48 at a high speed. As a result, the amount of air 
introduced by the air blower 16 is increased whereby the fresh air is 
forced into the air introduction pipe 17 and the cleaning pipe 20. 
Consequently, a large amount of air is jetted from the nozzle 49 which 
blows up the dust in the evaporation cauldron 28 and discharges the dust, 
together with air, from the discharge pipe 15. The dust-laden air 
discharged from the discharge pipe 15 is introduced into the dust 
collector 13 at a high speed wherein the air flows in a cyclonic or 
vertical path, as is conventional in cyclone dust collectors. The minute 
dust particles drop into the dust box 50 and accumulate therein. The air, 
having little or no dust suspended therein, passes through the separation 
pipe 54 and the deodorizing unit 14, and thereafter is diffused outside 
from the duct 61. 
Since the thus-separated dust that remains in the dust box 50 contains a 
liquid component, more or less, the liquid component is evaporated by the 
heater 51 to form a vapor. The vapor is introduced into the deodorizing 
unit 14 by way of the separation pipe 54, is oxidized by the catalyst 58 
and thereafter is discharged from the duct 61. Inasmuch as a large amount 
of air is introduced into the evaporation cauldron 28 by way of the 
cleaning pipe 20, the dust is moved together with the air and is 
discharged outside the evaporation cauldron 28. As a result, the cleaning 
operation is completed. 
When a series of steps composed of evaporation and cleaning operations is 
completed, the apparatus 1 should be in a standby state for the next user. 
When the control circuit 67 judges that the cleaning operation is 
completed, the control circuit 67 issues a signal to the standby operation 
circuit 68 so that the motor 47 is rotated at a low speed. As a result, a 
small amount of the fresh air is introduced into the discharge pipe 17. At 
the same time, the valve operation circuit 69 closes the first closing 
valve 18 and opens the second and third closing valves 19 and 27. The dry 
operation circuit 70 stops its operation, thereby stopping the inverter 
circuit 72 and the motor 42 and both the heaters 29 and 51 are 
deenergized. By this operation, the apparatus 1 is placed in the standby 
state. 
With the arrangement of the first embodiment, the cleaning of the dust, 
such as the waste matter, the ash and the like, which remains in the 
evaporation cauldron after the liquid component is evaporated, can be 
automatically carried out. Accordingly, it is not necessary to deassemble 
and clean the apparatus regularly so that the apparatus serves for a long 
time of use. Since the evaporation cauldron can be cleaned every time the 
evaporation operation of the urine is carried out, the inner portion of 
the evaporation cauldron can be always kept clean, thereby preventing 
trouble from occurring. 
Second Embodiment (FIGS. 7 to 12) 
A raw sewage disposing apparatus according to the second embodiment will be 
described with reference to FIGS. 7 to 12. 
The raw sewage disposing apparatus 101 comprises a cylindrical evaporation 
cauldron 111 and a dust collector 113 disposed alongside the evaporation 
cauldron 111. The cyclone dust collector 113 (hereinafter referred to as 
simply dust collector) is mounted on the upper surface of the dust box 112 
and a cylindrical catalyst box 114 is disposed above the dust collector 
113. A urine introduction pipe 103 is connected between the central side 
surface of the evaporation cauldron 111 and a stool 102. A discharge pipe 
116 is connected to a side surface of the evaporation cauldron 111 
opposite to the urine introduction pipe 103 and extends toward the dust 
collector 113. The discharge pipe 116 has a tip end connected to the dust 
collector 113 by way of a first closing valve 117. The apparatus 101 has 
an air blower 118 at the lower portion thereof. The air blower 118 has an 
air introduction pipe 119 which is branched into a first part provided 
with a second closing valve 120 and a second part provided with a third 
closing valve 121. The second closing valve 120 is connected to a cleaning 
pipe 122 which has a tip end connected to the side surface of the 
evaporation cauldron 111. A restriction pipe 123 is interposed in the 
cleaning pipe 122 so as to bypass the second closing valve 120 for 
controlling the amount of air that flows into pipe 122 to an appropriate 
value. A connection pipe 124 is connected to the third closing valve 121 
and has a tip end connected to a secondary heat box 125. The secondary 
heat box 125 has a heated output side connected to a preheat pipe 127. The 
preheat pipe 127 has a tip end connected to an ejector 128 which is 
restricted inside thereof. A pipe 129 is connected to an output side of 
the ejector 128 and has a tip end connected to the lower side surface of 
the catalyst box 114. A bypass 137 is connected between a part of the 
discharge pipe 116 upstream of the valve 117 and a negative pressure side 
on the ejector 128. A fourth closing valve 130 is interposed midway in the 
bypass pipe 137. 
FIG. 8 shows the piping system including the connections between the 
evaporation cauldron 111, the dust box 112 and the catalyst box 114. 
A fifth closing valve 131 is provided midway in the urine introduction pipe 
103 connected to the stool 102 while the tip end of the urine introduction 
pipe 103, downstream of the fifth closing valve 131, is connected to a 
substantially central side surface of the evaporation cauldron 111. The 
evaporation cauldron 111 is cylindrical and is closed at the lower portion 
thereof and is formed of a metallic heat-resistant material. The discharge 
pipe 116 is connected to the upper side surface of the evaporation 
cauldron 111 and has a tip end connected to the dust collector 113 by way 
of the first closing valve 117. Heating coils 135 are wound around the 
bottom surface and lower periphery of the evaporation cauldron 111. A 
temperature sensor 136 is connected to the side surface of the evaporation 
cauldron 111 for detecting the change of temperature of the evaporation 
cauldron 111. A drive mechanism 115 housing a motor and the like therein 
is placed on the evaporation cauldron 111 so that the upper opening of the 
evaporation cauldron 111 is closed. Accordingly, there is defined a 
chamber in the evaporation cauldron 111 which is shut off from the outside 
and is airtight. A long cylindrical rotary shaft 132 extends downwardly 
from the central portion of drive mechanism 115 and has stirring blades 
133 fixed at the lower portion thereof which blades are located close to, 
but spaced upwardly of the inner surface of the bottom of the evaporation 
cauldron 111. A plurality of spherical, freely movable, heat holding 
bodies 134 are stored in the evaporation cauldron 111 and are agitatable 
therein by the stirring blades 133. The heat holding bodies 134 are formed 
of materials having high heat holding property, such as alumina (Al.sub.2 
O.sub.3), pumice and the like. 
The air blower 118 has inside thereof a motor 142 and a fan 143 which is 
rotatable by the motor 142. The cleaning pipe 122 connected to the second 
closing valve 120 extends inside the evaporation cauldron 111 and has a 
tip end defining a nozzle 144 which opens downwardly. The restriction pipe 
123 is disposed around the section of the cleaning pipe 122 containing the 
valve 120 and has a small cross sectional area so that the restriction 
pipe serves as a bypass of the second closing valve 120. The connection 
pipe 124 has a tip end connected to the secondary heat box 125 which has a 
hollow inside. The secondary heat box 125 houses a secondary heater 145 
for heating the air supplied from the air blower 118. The preheat pipe 127 
is connected between the output side of the secondary heat box 125 and the 
input side of the ejector 128. 
The discharge pipe 116 and the suction side of the ejector 128 are 
connected by the bypass pipe 137. The fourth closing valve 130 is located 
in the bypass pipe 137. 
The air supplied to the dust collector 113 when the valve 117 is open, 
flows in a cyclonic path, so that any dust in the air supply is separated 
from the air. The dust collector 113 has a separation pipe 138 disposed at 
the central portion thereof and the pipe extends upwardly and communicates 
with the bottom of the catalyst box 114. The catalyst box 114 has a filter 
139 disposed at the lower portion thereof and a catalyst bed 140, such as 
platinum and/or palladium, which catalyst is disposed in the space above 
the filter 139. 
A control system according to the second embodiment will be described with 
reference to FIG. 9. 
An instruction switch 108 provided at the front portion of the apparatus 
101 has an output connected to a dry instruction circuit 152 which has an 
output connected to a central processing unit (hereinafter referred to as 
CPU) 151. An output of the temperature sensor 136 is connected to a 
temperature discrimination circuit 153 which has an output connected to 
the CPU 151. A power switch 150 is connected to the CPU 151 for starting 
the whole operation of the apparatus 101. The CPU 151 has outputs 
connected to a lamp 104, a motor control circuit 154, a valve control 
circuit 155 and a heater control circuit 156. The lamp 104, the motor 
control circuit 154, the valve control circuit 155 and the heater control 
156, respectively, receive instructions from the CPU 151 to thereby 
control each component thereof. The drive mechanism 115 and a motor 142 
are connected to the motor control circuit 154. The first to fifth closing 
valves 117, 120, 121, 130 and 131 are respectively connected to the valve 
control circuit 155. The heater 135 and the secondary heater 145 are 
respectively connected to the heater control circuit 156. 
The operation of the second embodiment will be described hereinafter. 
First, to establish the standby status of the apparatus, the power switch 
150 is turned on to enable the CPU 151 to instruct each component of the 
apparatus 101. The instruction is supplied to the lamp 104, the motor 
control circuit 154, the valve control circuit 155 and the heater control 
circuit 156. The motor control circuit 154, upon reception of the 
instruction from the CPU 151, actuates the motor 142 to thereby rotate the 
fan 143 and introduce the fresh air into the air introduction pipe 119. 
The valve control circuit 155, upon reception of the instruction from the 
CPU 151, opens the third and fifth closing valves 121 and 131 and closes 
the second, first and fourth closing valves 120, 117 and 130. The heater 
control circuit 156, upon reception of the instruction from the CPU 151, 
energizes the secondary heater 145 which heats the air passing through the 
secondary heat box 125. At this state, the fresh air is drawn from the 
atmosphere by the fan 143 and supplied to the ejector 128 by way of the 
air introduction pipe 119, the third closing valve 121, the connection 
pipe 124, the secondary heat box 125 and the preheat pipe 127 and further 
passes through the catalyst box 114 and finally is discharged toward the 
atmosphere whereby an air flow route is formed between the inlet from the 
air blower 118 to the outlet of the catalyst box 114. At this time, the 
secondary heater 145 is energized and heated so that the flowing air can 
be heated by the secondary heater 145. The heated air heats the catalyst 
140 when it passes through the catalyst box 114 to thereby maintain the 
temperature of the catalyst so that the catalyst 140 can subject the vapor 
to the oxidation-reduction. 
The apparatus 101 can be used while it is in the standby state described 
above. The apparatus 101 can store the discharged urine in such a manner 
that the discharged urine is first received by the stool 102 and stored, 
then passed through the urine introduction pipe 103, the fifth closing 
valve 131 and finally is stored in the evaporation cauldron 111. The one 
time disposing capacity of urine in the apparatus 101 is determined by the 
volume of the evaporation cauldron 111. 
When the evaporation and drying operation is to be carried out, the 
instruction switch 108 is pressed so that the urine in the evaporation 
cauldron 111 can be evaporated when it is judged that the predetermined 
amount of urine is stored in the evaporation cauldron 111 and no more 
urine can be stored. An instruction signal issued by the instruction 
switch 108 is supplied to the dry instruction circuit 152. The dry 
instruction circuit 152, upon reception of the instruction from the switch 
108, issues a signal that the evaporation can be effected because the 
predetermined amount of urine is stored in the cauldron 111. This signal 
is supplied to the CPU 151. The CPU 151, upon reception of the signal from 
the dry instruction circuit 152, supplies a signal to the motor control 
circuit 154, the valve control circuit 155 and the heater control circuit 
156 so that they can start the drying operation. 
Firstly, the motor control circuit 154 actuates the drive mechanism 115 so 
that the motor 142 is driven whereby the rotary shaft 132 and the stirring 
blades 133 are respectively rotated in the evaporation cauldron 111, which 
also involves the agitation of the heat holding bodies 134. The 
temperature of the stored urine is kept constant because of the rotation 
of the stirring blades 133 and agitation of the heat holding bodies 134 in 
the evaporation cauldron 111. At the same time, the valve control circuit 
155 opens the fourth closing valve 130 and closes the fifth closing valve 
131 while the third closing valve 121 is kept opened (at this time, the 
first closing valve 117 and the second closing valve 120 are kept closed). 
The fresh air from the air blower 118 passes through the air introduction 
pipe 119, the third closing valve 121, the connection pipe 124, the 
secondary heat box 125, the preheat pipe 127, the ejector 128 and the 
supply pipe 129 and is introduced into the catalyst box 114, and then is 
diffused to the atmosphere. At this time, a negative pressure is generated 
at the side of the bypass pipe 137, caused by the air that passes through 
the ejector 128, so that the air in the discharge pipe 116 is drawn into 
the ejector 128 by way of the fourth valve 130. Accordingly, drawn into 
the ejector 128 is the fresh air which passes through the air introduction 
pipe 119, the restriction pipe 123 and the cleaning pipe 122 and is 
introduced into the evaporation cauldron 111, so that a second air flow 
route is provided in addition to the first air flow route provided by the 
connection pipe 124. Inasmuch as the inner diameter of the restriction 
pipe 123 is small in the second air flow route, the amount of air flowing 
in the second air flow route is less than that of the first air flow 
route. When the fresh air is introduced by way of the air blower 118, the 
oxidation of the urine stored in the evaporation cauldron 111 is 
facilitated. When the heater 135 is energized by the heater control 
circuit 156, the evaporation cauldron 111 is heated at the side and bottom 
thereof so that the urine stored in the evaporation cauldron 111 is 
boiled. 
The urine stored in the evaporation cauldron 111 is heated and boiled by 
the heater 135 when the heater control circuit 156 receives the 
instruction from the CPU 151 so that the liquid component of the urine is 
evaporated so as to be changed into a vapor. The vapor passes through the 
discharge pipe 116, the fourth closing valve 130, the bypass pipe 137 and 
is drawn into the ejector 128 by the air flow through the ejector 128 and 
then passes through the catalyst box 114. After passing through the 
catalyst box 114, the vapor is diffused into the atmosphere. Since the air 
heated by the secondary heater 145 flows within the secondary heat box 
125, the vapor flowing from the bypass pipe 137 is mixed with the heated 
air and is reheated. As a result, although the temperature of the vapor 
formed in the evaporation cauldron 111 is reduced as it flows through the 
discharge pipe 116, the fourth closing valve 130 and the bypass pipe 137, 
the temperature of the vapor is increased when it is mixed with the hot 
air in the ejector 128. Accordingly, the vapor formed in the evaporation 
cauldron 111 contacts the catalyst 140 in the catalyst box 114 and is 
subjected to oxidation-reduction because it is heated to a sufficiently 
high temperature for the reaction to take place effectively. The vapor 
including the bad smell component, such as ammonia and bromine, contacts 
the catalyst 140 and is subjected to the oxidation-reduction reaction 
whereby it is changed into an odorless vapor and then is diffused into the 
atmosphere. 
The rotary shaft 132 and the stirring blades 133 are rotated in the 
evaporation cauldron 111 by the drive mechanism 115 whereby the heat 
holding bodies 134 housed in the evaporation cauldron 111 at the bottom 
portion thereof are agitated by the stirring blades 133. The temperature 
of the urine stored in the evaporation cauldron 111 rises uniformly as a 
whole since the urine is stirred by the rotation of the stirring blades 
133 and the heat holding bodies 134. Likewise, since the heat holding 
bodies 134 hold the heat therein, the urine contacts the surfaces of the 
heat holding bodies 134 by the rotation of the stirring blades 133 so that 
the heat held by the heat holding bodies 134 is transmitted to the urine 
which involves an increase of the temperature of the urine. 
The liquid component constituting the main portion of the urine stored in 
the evaporation cauldron 111 is evaporated due to the heating operation by 
the heater 135 and the stirring operation by the stirring blades 133 and 
the heat holding bodies 134. There remains in the evaporation cauldron 111 
solid residual substances, such as cellulose fibers. The residual 
substance is liable to adhere to the bottom of the evaporation cauldron 
111 during long term usage thereof, which would hinder the drying 
operation. Accordingly, when the drying operation is completed, the 
residual substance remaining in the evaporation cauldron 111 and the dust 
must be removed so that the cauldron is cleaned. The cleaning operation is 
automatically made in succession when it is judged that all the urine in 
the evaporation cauldron 111 has been dried. 
When the urine in the evaporation cauldron 111 is completely evaporated and 
dried, the temperature of the evaporation cauldron 111 at the side thereof 
rises. The rise of the temperature is detected by the temperature sensor 
136 which issues a detection signal to the temperature discrimination 
circuit 153. The temperature discrimination circuit 153 issues a cleaning 
start operation signal to the CPU 151. The CpU 151, upon reception of the 
signal from the temperature discrimination circuit 153, lights the lamp 
104 which indicates that the evaporation cauldron 111 is ready for a 
cleaning operation. The CPU 151 also issues the signal respectively to the 
motor control circuit 154, the valve control circuit 155 and the heater 
control circuit 156. The motor control circuit 154 supplies high frequency 
power to the motor 142 by way of an inverter whereby the rpm of the motor 
142 is increased. The increase of rpm of the motor 142 rotates the fan 143 
at a higher speed so that the amount of air introduced by the air blower 
118 is increased. The valve control circuit 155 closes the fourth closing 
valve 130 and opens the second valve 120 and the first closing valve 117 
(at this time, the third closing valve 121 remains open while the fifth 
closing valve 131 remains closed). As a result, the second air flow route 
is formed by the air introduction pipe 119, the second closing valve 120, 
the cleaning pipe 122 and the nozzle 144 whereby the air is forced to jet 
from the nozzle 144. The residual substance stored in the evaporation 
cauldron 111 is blown away by the high speed air jet introduced through 
nozzle 144. The residual substance and the dust blown up by the air jetted 
by the nozzle 144 passes through the discharge pipe 116 and the first 
closing valve 117 and thereafter is introduced into the dust collector 
113. Since the outer casing of the dust collector 113 is restricted in a 
downward direction, the air flow is turned like a cyclone or vortex at 
high speed so that the particles of residual substance, which particles 
are heavier than the air, drop into the dust box 112 and air alone flows 
upwardly toward catalyst box 114 from the separation pipe 138 and 
thereafter is diffused into the atmosphere. As a result, the particles of 
residual substance are separated from the vapor by the dust collector 113. 
During this time, the drive mechanism 115 is operated continuously, 
thereby agitating the heat holding bodies 134 at the bottom of the 
evaporation cauldron 111. As a result, any residual substance that is 
adhered to the bottom and the inside portion of the evaporation cauldron 
111 is crushed to become minute particles. There is also provided the 
first air flow route through which the fresh air flows by way of the third 
closing valve 121, the connection pipe 124, the secondary heat box 125, 
the preheat pipe 127 and the ejector 128. Because of the existence of the 
first air flow route, the temperature of the secondary heater 145 is 
prevented from rising sharply and from becoming damaged. After the 
cleaning operation has been carried out for a given time, the CPU 151 
makes the judgment that the residual substance in the evaporation cauldron 
111 has been eliminated and stops the cleaning operation. 
As described above, the air is jetted from the nozzle 144 when the motor 
142 is driven by the high frequency current from the inverter so that the 
residual substance in the evaporation cauldron 111 is blown out of the 
cauldron. Thereafter, the apparatus 101 is returned to the standby state 
for the next user. The CPU 151 supplies the signal to the motor control 
circuit 154, the valve control circuit 155 and the heater control circuit 
156 so that all these circuits are switched to the standby state. The 
motor control circuit 154 returns the rpm of the motor 142 to the normal 
rpm, i.e., to the decreased rpm. Simultaneously, the rotation of the 
rotary shaft 132 by the drive mechanism 115 is stopped. The valve control 
circuit 155 closes the first, the second and the fourth closing valves 
117, 120 and 130 and at the same time opens the fifth closing valve 131. 
Consequently, the stool 102 communicates with the inside of the 
evaporation cauldron 111 so that urine discharged toward the stool 102 is 
introduced into the evaporation cauldron 111. The heater control circuit 
156 deenergizes the heater 135 while energizing the secondary heater 145. 
The cycle of operations comprising the drying operation, the cleaning 
operation and the standby state operation can be repeated. Repetition of 
the cycle of operations enables the apparatus 101 to provide a long time 
period of usage. When the apparatus 101 is not to be used anymore or is to 
be stopped temporarily, the power switch 150 is operated to supply an 
instruction signal to the CPU 151. The CPU 151, upon reception of the 
instruction signal, stops the power supply to all the mechanisms, which 
causes termination of operation of the apparatus. The series of operations 
are illustrated in the flowcharts in FIGS. 10 to 12. 
As mentioned above, according to the second embodiment, the air evaporated 
at the evaporation cauldron is drawn by the ejector, mixed with the hot 
air heated by the secondary heater at the ejector and is reheated by the 
hot air. The thus-heated hot air contacts the catalyst whereby the bad 
smell component is favorably subjected to the oxidation-reduction 
reaction. As a result, the bad smell component is rendered odorless and is 
diffused into the atmosphere. The secondary heater for heating the 
catalyst does not directly contact the vapor from the evaporation cauldron 
and is not provided at the vapor flow route. As a result, the secondary 
heater is neither oxidized nor deteriorated by the various components 
included in the vapor which assures the long time use of the secondary 
heater.