JPS5838229B2 - How to dispose of waste - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a waste treatment method for efficiently treating human waste and garbage.

Conventionally, human waste treatment facilities and garbage treatment facilities have often been installed on the same site or adjacent to each other, but each has its own treatment process, which poses the following problems.

First, in night soil treatment, raw human waste is treated with sediment removal, digestion, and aeration, and the final treated water is sterilized and then released. Digested sludge and surplus activated sludge generated during aeration treatment are dehydrated and then incinerated.

Therefore, human waste treatment requires incineration equipment for the dehydrated cake after sludge dewatering, and dehydrated cake generally has a high water content and low calorific value, so there is a problem that the water load is large and the amount of heavy oil used is large.

On the other hand, in garbage treatment, waste is incinerated, dust is removed from the exhaust gas, harmful gases are removed, and the exhaust gas is released into the atmosphere after being washed with water. However, if the quality of the garbage is poor, sump pit drainage with considerably high BOD and SS occurs. Since this cannot be incinerated, water treatment equipment is required.

In addition to garbage pit drainage, water treatment equipment is also required for cooling drainage, drainage generated during dust removal, harmful gas removal, and water washing.

In this way, conventional human waste treatment and garbage treatment both require water treatment equipment and incineration treatment equipment, which require management,
It took time and effort to maintain, increased construction costs, upkeep costs, maintenance costs, etc., and had drawbacks such as requiring a large site area.

The present invention focuses on the fact that some of the processing equipment in human waste treatment and garbage processing overlaps, and by integrating these processes, it can be processed rationally according to the properties of the objects to be treated, and the operation can be improved. Management and maintenance can be carried out economically,
Furthermore, it provides a waste disposal method that can reduce construction costs, maintenance costs, and site area.

That is, the present invention integrates and processes wastewater generated in the waste incineration process, such as wastewater from waste pits, cooling wastewater, dust collection, harmful gas removal, and water washing, in a water treatment facility, while treating septic tank sludge and wastewater. The digested sludge and activated sludge generated in the human waste water treatment process are treated in the waste incineration process.

An embodiment of the method of the present invention will be described below with reference to the drawings.

The drawing is a flowchart showing a waste treatment method. This treatment method organically integrates and combines the garbage incineration treatment process, the septic tank sludge treatment process, and the human waste treatment process. It is.

In the garbage incineration process, garbage 1 is transferred to garbage pit 2.
It is burned in an incinerator 3 and the ashes are put into an ash pit 4.

Further, the exhaust gas is passed through the boiler 5, and the heat of the exhaust gas is used to rotate the turbine 6, and the in-house power generation equipment 7 generates electricity to supply electricity.

The exhaust gas that has passed through the exhaust gas boiler 5 is transferred to an electrostatic precipitator 8.
After passing through a noxious gas removal device 9 to remove harmful gases such as HCl, SOx, NOx, etc., the gas is washed with water through a water washing tower 10 to dehumidify and remove odor, and then released into the atmosphere.

In the treatment process for septic tank sludge, septic tank sludge 11 is directly put into a dehydrator 13 from a storage tank 12 to produce a dehydrated cake, which is then put into a cake hopper 14 and then transferred to a dryer 15.
Put it in.

A part of the high temperature exhaust gas generated in the incinerator 3 passes through the dryer 15, and the dehydrated cake is dried using the heat of this exhaust gas.

Note that the exhaust gas after drying is returned to the incinerator 3 and deodorized.

The dried cake dried in the dryer 15 is placed in the garbage pit 2.
The waste is then incinerated in the waste incineration process.

In the raw human waste processing process, raw human waste 16 is transferred to a receiving tank 17.
and put it into the residue removal equipment 18.

The residue removed here is passed through a dehydrator 19 to be dehydrated and thrown into the garbage pit 2 as residue.

On the other hand, the removed human waste is put into a storage tank 20, further into a digestion tank 21 for digestion, and then into a settling tank 22 to be separated into a desorbed liquid and digested sludge.

The desorbed liquid is diluted in a dilution tank 23, then aerated in an aeration tank 24, and separated into sludge and treated water in a final settling tank 25.

Thereafter, this treated water is disinfected in a disinfection tank 26, and part of it is used for cleaning in the water washing tower 10, and the rest is discharged.

A part of the activated sludge separated in the final settling tank 25 is re-injected into the aeration tank 24 as return sludge, while the remainder is thrown into the sludge storage tank 28 after passing through the thickening tank 27 as surplus sludge.

This sludge storage tank 28 is charged with digested sludge separated in the settling tank 22. After the sludge in the sludge storage tank 28 is dehydrated in a dehydrator 29, it is put into the cake hopper 14 as a dehydrated cake. The material is dried in the dryer 15 and put into the comic pit 2, and then incinerated in the incineration process.

Further, the filtrate generated in the dehydrator 29 is charged into the dilution tank 23, and similarly, the filtrate generated in the dehydrator 13 of the septic tank sludge 11 is stored in the dewatered filtrate storage tank 30, and is input into the dilution tank 23. .

In addition, from garbage pit 2 in the garbage incineration process, BOD
, SS is produced, and this waste pit waste water 31 is fed into the sludge removal equipment 18 and treated in the human waste treatment process.

In addition, car wash wastewater from cleaning cars, cooling water 32 from incinerator 3,
Wet wastewater 33 generated when the electrostatic precipitator 8 is a wet type, absorption wastewater 34 used in the harmful gas removal device 9, and washing wastewater 35 used in the water washing tower 10 are all pretreated and then transferred to the dilution tank 22.
After that, it is processed in the raw human waste processing step (secondary processing step).

According to the above-mentioned treatment method, combustible materials such as dehydrated sludge, dehydrated cake of digested sludge and excess sludge, and dehydrated cake of septic tank sludge generated in the human waste treatment process are incinerated in the garbage incineration treatment process. Therefore, there is no need to provide separate incineration equipment in the human waste processing process.

Furthermore, since the dehydrated cake is dried in the dryer 15 using the exhaust gas from the incinerator 3, it can be incinerated without placing an excessive burden on the incinerator 3.

Further, garbage pit wastewater 31 generated in the garbage incineration process is input to the slag removal equipment 18 in the human waste treatment process, and is thereafter treated together with the human waste, cooling water 32 in the incineration process, wet sewage 33 in the electrostatic precipitator 8, and harmful gases. The absorption waste liquid 34 in the removal device 9 and the washing waste liquid 35 in the water washing tower 10 are pretreated and then input into the dilution tank 23, so that water treatment equipment can be installed separately in the waste incineration process. There is no need to provide one.

Furthermore, since the washing water used in the water washing tower 10 is a part of the treated water finally obtained in the human waste treatment process, it is economical.

In this embodiment, the septic tank sludge 11 is directly dehydrated and only the filtrate is fed into the dilution tank 23 (secondary treatment equipment side). The reason why we did not use a mixed treatment method is as follows.

In other words, in human waste treatment facilities, human waste and septic tank sludge have traditionally been mixed and treated, but the septic tank sludge has already undergone biological treatment in the septic tank.

Therefore, the concentration of BOD and organic matter is low, the balance of nutrients and substrates for microorganisms is disrupted, and there is a large qualitative variation range, and the properties are markedly different from raw human waste.For this reason, the average input ratio of septic tank sludge is operated at around 20%. It is normal to do so.

However, in facilities near cities, there are cases where the ratio of septic tank sludge input exceeds 50 cubic meters, and when septic tank sludge is input in large quantities and irregularly in this way, it poses a major hindrance to treatment functions and maintenance management.

In response to this, expansion or new construction of human waste treatment facilities may be considered.
It is difficult to secure land.

For this reason, in the above embodiment, by directly dewatering the septic tank sludge 11 without mixing it with raw human waste 16, the qualitative fluctuation range of the septic tank sludge is suppressed, and the primary treatment equipment such as the digestion tank 21 This makes it possible to reduce the load on equipment and make the equipment more compact.

In this case, the filtrate obtained by directly dewatering the septic tank sludge 11 contains, for example, 150 to 500 ■/l of SS (removal rate of about 98φ), BO
D can be removed to a removal rate of 1,500 to 4,500 μ/lc (approximately 73 parts), and this can be directly input into the dilution tank 23 of the secondary treatment facility.

In addition, when a gas cooling tower is used instead of the exhaust gas boiler 5, the filtrate obtained by dehydrating the septic tank sludge can be used as the cooling water, and in this case, the load on the secondary treatment equipment for human waste treatment can be reduced. .

Next, we will calculate the facility scale, material balance, and heat balance when the treatment method shown in the figure is implemented in a suburban area with a total population of 300,000 people, and compare the results with conventional treatment methods.

First, Table 1 shows the amount of septic tank sludge, human waste, and garbage processed by the method of the present invention, and Table 2 shows the properties of the incinerated material processed in the incinerator. Table 3 shows the equipment scale operating conditions for each equipment.

The material balance and heat balance in this example are as follows.

First, in the incineration process, combustible materials (20'CI400K!ult/
132.9 tons/day of combustion air (183°C) was input, and 3.9 8 7 XIO5 of preheated combustion air (183°C) was input
Blow air at Nml per day.

The incineration process generates exhaust gas at 850°C, but a portion of it, 1.323X104Nrrt/day, is sent to the dryer.
The remainder is sent to the waste heat boiler.

Exhaust gas after drying the cake through the dryer (160°
C) becomes 1.6 6 3 X 1 0'Nrri'7 days and is returned to the incinerator.

The heat balance around the incinerator is as follows.

1.8 7 0 X 1 by incinerating flammable materials
There is a heat generation of 0.08 Kd/day, and the amount of heat brought in by the combustion air is 2.698 x 107 Km/day.

The amount of heat carried away by the exhaust gas after combustion is 2,071.
X 1 08Km 7 days, heat loss due to heat radiation from the furnace, etc. is 6.
0 9 7 X 1 0'Kd/day, and the amount of heat carried away by the incinerated ash is 1.7 5 2 X 1 0'Km/day.

In addition, in the septic tank sludge treatment process, SS100 is used in the dehydrator.
8 septic tank sludge containing 00■/l, BOD6500■/l
0771"/day, and the dehydrated cake and filtrate are separated.

The dehydrated cake is produced at 2800 kg/day with a moisture content of 65% and a temperature of 20° C., and is fed into a dryer.

In addition, the filtrate obtained by dehydration is SS2oOTn9/l, B
OD1750TIv? /A, 80ml is produced per day and this is put into a dilution tank or sprayed and incinerated in an incinerator.

In addition, in the process of processing raw human waste, SS1000 is used in the digestion tank.
07V/l, BOD13000Tu? Inject 120 m of raw human urine containing 7 days a day.

Here, it is separated into digested sludge and desorbed liquid, and the digested sludge has a moisture content of about 97 mL and is produced in an amount of 19 ml per day and is then put into a dehydrator.

Also, the desorption liquid is SS2200m9/l, BOD2600
120 m'/l was produced for 7 days, and this was placed in a dilution tank.

Dilution water of 4000 m/mill is poured into this dilution tank.

Is the diluted desorption solution SS66rru? /l,BOD10
7m9/n, and 4200m7 days of diluted liquid is put into the aeration tank.

After being treated in the aeration tank, it is separated into activated sludge and supernatant water, and a portion of the activated sludge is extracted as surplus sludge (99% water content) at a rate of 7 m/day and fed into a dehydrator.

Digested sludge and excess sludge are separated into filtrate and dehydrated cake using a dehydrator L, SS200IV/A BOD5001V/6■
Liquid 26i/day power dilution tank Kff person 1 dehydration case 2
The moisture content is 70% at 0°C, and 2100 kg is put into a dryer for 7 days.

After drying a dehydrated cake such as digested sludge and a dehydrated cake of septic tank sludge in a dryer, 2010 kg/day of dry cake of 70'C and 2330 KcaVkg is obtained.

According to this method, garbage treatment and urine treatment are organically combined, so the administration building is reduced to one building, and the human waste treatment facility is reduced by about 40% compared to the conventional one, resulting in a total of approximately 30% % equipment scale can be reduced.

In addition, since less equipment is required than before, the construction cost can be reduced by about 15 mm and the maintenance cost by about 35 mm.

In addition, the waste treatment facility must incinerate the human waste and dried cake discharged from the human waste treatment facility, but the increase in maintenance costs for this is approximately 0 compared to the maintenance cost of the waste treatment facility with the conventional treatment system. .3 units, which is extremely small.

As explained above, according to the present invention, garbage treatment and urine treatment are integrated and treatment is carried out according to the properties of the object to be treated, so an economical operation management and maintenance system can be established, and the construction of the facility is possible. It has remarkable effects, such as lowering costs, maintenance costs, and reducing site area.

[Brief explanation of the drawing]

The drawing is a flow sheet diagram of a waste treatment method showing an embodiment of the present invention. 1...garbage, 2...garbage pit, 3.
...Incinerator, 8...Electrostatic precipitator, 9...
... Harmful gas removal device, 10 ... Water washing tower,
11...Septic tank sludge, 13,19.29...
...Dehydrator, 14...Cake hopper-15.
...Dryer, 16...Raw urine, 18...
...Silence removal equipment, 21...Digestion tank, 22...
... Sedimentation tank, 23 ... Dilution tank, 24 ...
...Aeration tank, 25...Final sedimentation tank, 27...
... Thickening tank, 31 ... Garbage pit drainage, 3
2...Cooling water, 33...Wet drainage, 3
4...Absorption and drainage liquid, 35...Cleaning drainage liquid.

Claims (1)

[Claims] 1. A waste incineration treatment process in which waste is incinerated, the exhaust gas is purified and released into the atmosphere, and human waste and human waste and solid matter are separated and removed, and the separated liquid is subjected to biological treatment and discharged. In a waste treatment method comprising a water treatment process for human waste, the human waste produced in the water treatment process is dehydrated, the sludge is dried with exhaust gas generated from waste incineration after dehydration, and then the waste is incinerated. A method for treating waste, characterized in that the waste is treated in a treatment step, and the waste liquid generated in the incineration treatment step is treated in a human waste water treatment step. 2. Claims characterized in that the sludge to be incinerated after dewatering consists of digested sludge produced by digesting septic tank sludge and human waste; and activated sludge produced by aerating digested liquid A method for treating waste as described in paragraph 1. 3. Claim 1, characterized in that the treated water obtained in the human waste water treatment process is used for cooling and purifying exhaust gas.
How to dispose of the waste described in Section 1. 4. The waste treatment method according to claim 2, characterized in that the septic tank sludge dewatering filtrate is spray-incinerated in an incinerator.