JPH074598B2 - Human waste system treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to human waste or human waste as well as human waste sewage such as septic tank sludge generated from domestic septic tanks (hereinafter simply referred to as “human waste”). To a device for processing.

[Prior Art] Conventionally, the normally used human waste treatment is a biological nitrification denitrification treatment of the waste urine obtained by removing the waste with a screen having an opening of about 3 to 5 mm, and after the coagulation sedimentation treatment. Those that undergo tertiary treatment such as filtration, activated carbon adsorption treatment, etc.

A method in which human waste is directly dehydrated to remove most of the solids, the separated water is biologically treated, and the treated liquid is subjected to coagulation sedimentation treatment, filtration, and activated carbon adsorption.

A biological treatment of human waste followed by membrane separation.

Etc.

[Problems to be Solved by the Invention] However, none of the above-mentioned conventional methods can perform good urine treatment. That is, in the method of biological nitrification denitrification treatment of the decontaminating urine, which is subjected to coagulation sedimentation treatment, filtration and activated carbon adsorption treatment, due to SS contained in human waste, in the nitrification denitrification tank. Foaming is remarkable and undecomposed substances remain in the nitrifying denitrification treated water,
There are problems such as high COD _Mn and high chromaticity of the treated water, which further has a drawback that the coagulation-sedimentation treatment and the activated carbon adsorption treatment in the subsequent process are adversely affected. Moreover, in this case, a coagulation sedimentation tank, a filtration tower, an activated carbon adsorption tower and a backwash drainage tank are required, which causes a problem that the site area becomes large.

Also, the above requires a tertiary treatment facility similar to the above, and in the above, SS contained in the human waste
Due to the problem caused by, the membrane is significantly clogged and the amount of permeated water is significantly reduced. Therefore, there is a problem that the membrane must be frequently washed and the life of the membrane is shortened.

[Means for Solving Problems] The present invention solves the above-mentioned conventional problems, and when treating human waste sewage using a membrane separator, the membrane is less clogged and the amount of permeated liquid is reduced. It is an object of the present invention to provide a treatment apparatus for human wastewater that can improve the quality of treated water without lowering it and can significantly extend the operating life of the membrane.

In order to achieve this object, the treatment apparatus for night soil sewage according to the present invention comprises means for dehydrating night soil sewage, means for biologically nitrifying and denitrifying the water separated from the dehydrating means, and the nitrification and denitrification. The biological treatment liquid from the means is directly separated into a membrane without solid-liquid separation.

[Operation] In the device of the present invention, a means for directly dehydrating human waste is provided, and most of the solid content in human waste is previously removed. Therefore, in the subsequent biological nitrification denitrification means, foaming due to SS is generated. In addition to being suppressed, COD _Mn and chromaticity of the biological treatment liquid are low and a favorable treatment liquid can be obtained. Further, since the treatment liquid is subjected to a membrane treatment, clogging of the membrane is reduced, the quality of treated water and the amount of permeated liquid can be improved, and the operating life is remarkably extended.

Embodiments Embodiments will be described below with reference to the drawings. FIG. 1 is a system diagram of an apparatus according to an embodiment of the present invention. In FIG.
The decontamination urine from which contaminants have been removed by a screen or the like having an opening of 3 to 5 mm is sent to the dehydrating means A without being subjected to biological treatment, and is dehydrated. In this example, the agglutination reaction tank 1 was provided before the dehydration treatment,
A coagulant such as a cation polymer is added from the pipe 11 to remove the residue and coagulate the urine.

In addition, in the present embodiment, the human waste sent to the agglutination reaction tank 1 is decontamination urine, but in the present invention, raw human urine may be introduced into the agglutination reaction tank 1.

Hereinafter, a case of processing decontamination urine will be described. First
In the figure, the coagulation reaction treated product is sent from a pipe 12 to a dewatering means A composed of a rotary screen 2 (opening of about 0.3 to 1 mm) and a screw press 3, and most of solid matter is dewatered and removed. The cake obtained by being sufficiently dehydrated by the rotary screen 2 and the screw press 3 is discharged by the cake extracting means 13 and disposed of by incineration or soil reduction.

On the other hand, the fractionated water separated by the dehydration treatment means A is sent to the biological nitrification / denitrification means B through the pipe 14.

In the biological nitrification and denitrification means B, in the nitrification and denitrification tank 4,
BOD components, decomposition, and nitrification and denitrification of nitrogen components are applied.
An excess sludge content due to the nitrification denitrification treatment is sent to the coagulation reaction tank 1 through a pipe 15. The treatment liquid is sent to the membrane separating means C as it is without solid-liquid separation through the pipe 19.

The membrane separation means C is preferably a multistage membrane separation of an ultrafiltration (UF) membrane or a reverse osmosis (RO) membrane.

In the illustrated embodiment, the biological treatment liquid is first sent to the ultrafiltration membrane separation device 7 through the pipe 19. In the ultrafiltration membrane separation device 7, the high molecular weight substance in the liquid (for example, the molecular weight 2
80 to 90% is excluded, the membrane contamination in the reverse osmosis membrane in the subsequent step is reduced, and the decrease in the amount of permeated water is prevented. The concentrated liquid of the ultrafiltration membrane separation device 7 is returned to the nitrification denitrification tank 4 through the pipe 20, and the permeated liquid is supplied through the pipe 21 to the reverse osmosis membrane separation device 8.
Sent to.

In the reverse osmosis membrane separation device 8, the permeate of the ultrafiltration membrane separation device 7 is further subjected to reverse osmosis treatment to be highly purified treated water.

The reverse osmosis membrane permeate is taken out as treated water from the pipe 22 and sent to the discharge step.

On the other hand, the concentrated liquid of the reverse osmosis membrane separation device 8 is taken out of the system through the pipe 23 and appropriately treated.

According to the apparatus of this embodiment, COD _{Mn is} generally 20 mg / l or less, chromaticity is 20 or less, T-P is 1 mg / l or less, T-N is 10 mg / l or less, and BOD is 10 mg.
Treated water of extremely excellent water quality of less than / l can be obtained.

The shape of the ultrafiltration membrane and the reverse osmosis membrane in the membrane separation means C may be any of a flat plate type membrane, a tubular type membrane, a spiral wound type membrane, a hollow type membrane and a fold type membrane, and the material of the membrane is In the case of the ultrafiltration membrane, polysulfone, polyacrylonitrile, polyolefin, etc. may be mentioned. Then,
As the reverse osmosis membrane, a loose reverse osmosis membrane having a salt removal rate of about 30 to 50% is preferable, and as its material, a material mainly composed of cellulose acetate and a synthetic polymer mainly composed of aromatic polyamide Although any of these types can be used, synthetic polymer type is preferable because of its excellent chemical resistance.

Experimental Example 1 (Example of the present invention) The apparatus of the present invention shown in FIG.

That is, a cationic polymer flocculant was added to the waste urine at a rate of 1.4% / ds in the flocculation reaction tank 1 to cause flocculation, and then solid-liquid separation was performed with a rotary screen 2 and a screw press 3. The water quality of the separated liquid is shown in Table 1 as raw water. Next, this raw water was treated in the nitrification denitrification tank 4. The water quality is shown as a biological treatment liquid.

This biological treatment liquid was subjected to membrane separation treatment by an ultrafiltration membrane separation device 7 and a reverse osmosis membrane separation device 8 to obtain treated water. The concentrated liquid of the reverse osmosis membrane separation device 8 was incinerated.

The permeated liquid of the ultrafiltration membrane separation device and the permeated liquid of the reverse osmosis membrane separation device are shown in Table 1 for the quality of the treated water and the amount of permeated water.

In addition, the ultrafiltration membrane separator (UF) is used once every two days with NaOH (0.
5%) and reverse osmosis membrane separator (RO) daily with NaOH (0.1%).
%) For 30 minutes each. Then, the amount of permeated water after cleaning the membrane was measured at the initial stage and after the lapse of 3 months. For the measurement of the amount of permeated water, UF is pure water and RO is NaCl.
(0.2%). The measurement results are shown in Table 1.
The NaCl removal rate of RO is also shown in Table 1.

Experimental Example 2 (Comparative Example) In Experimental Example 1, the decontaminated urine was introduced into the nitrification denitrification tank 4 without solid-liquid separation treatment and treated. (Table 1 shows the water quality of the decontaminated urine at that time. Further, Table 1 shows the water quality of the nitrification denitrification treated water as a biological treatment liquid.) This biological treatment liquid is used for the ultrafiltration membrane separation device 7 And the permeated liquid was subjected to a membrane separation treatment by a reverse osmosis membrane separation device 8.
The water quality of each permeate was as shown in Table 1.

Further, Table 1 shows the permeated water amount after the membrane washing and the NaCl removal rate of RO measured in the same manner as in Experimental Example 1.

From Table 1, according to the present invention in which most solids in human waste are subjected to solid-liquid separation, the COD of the liquid introduced into the biological treatment means, as compared with the conventional one which does not perform solid-liquid separation, BOD,
It is recognized that the SS concentration is extremely low. It is recognized that, by thus reducing the load on the biological treatment, the treatment efficiency in the biological treatment means is improved and the treated water quality becomes excellent.

Further, from Table 1, it is recognized that the amount of permeated water obtained by the membrane separation treatment is large in the device of the present invention. Furthermore, in the device of the present invention, the decrease in the amount of permeated water of the membrane separation device after three months of operation is small, and in particular, it is recognized that the operating life of the ultrafiltration membrane separation device is significantly extended.

[Effects] As described above in detail, the present invention is configured to include the means for dehydrating human urine, the means for biological nitrification and denitrification, and the means for membrane separation, and the load on biological treatment is reduced and treatment is efficiently performed. In both cases, the permeated liquid amount of the membrane separation device is less reduced, and the membrane life is greatly extended. Further, nitrogen, phosphorus, COD, BOD, SS and the like contained in human waste can be efficiently removed, and treated water of extremely excellent water quality can be stably obtained.

[Brief description of drawings]

FIG. 1 is a system diagram of an apparatus according to an embodiment of the present invention. A ... Dehydration means, B ... Biological nitrification and denitrification means, C ... Membrane separation means, 1 ... Aggregation reaction tank, 2 ... Rotary screen, 3
... screw press, 4 ... nitrification denitrification tank, 7 ... ultrafiltration membrane separator, 8 ... reverse osmosis membrane separator.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location C02F 9/00 503 D 7446-4D (72) Inventor Mitsuharu Furuichi 1723 Houkagai-cho, Hodogaya-ku, Yokohama-shi, Kanagawa Address Kurita Industry Co., Ltd. General Research Institute (72) Inventor Naoto Ichiyanagi 1723, Homukaicho, Hodogaya-ku, Yokohama-shi, Kanagawa Inside Kurita Industry Co., Ltd. (56) Reference JP-A-55-155798 (JP, A) JP Showa 54-132353 (JP, A)

Claims (2)

[Claims] 1. A means for dehydrating human waste sewage, a means for biologically nitrifying and denitrifying the separated water from said dehydrating means, and a biological treatment liquid from said nitrifying and denitrifying means without solid-liquid separation. A treatment device for human waste water, comprising a means for membrane separation. 2. The apparatus according to claim 1, wherein the membrane separation means is a combination of ultrafiltration membranes and / or reverse osmosis membranes in multiple stages.