JPS5889992A - Treatment for night soil - Google Patents

Abstract

PURPOSE:To remove colloidal components in night soil and to reduce foaming by subjecting the night soil and the sludge subjected to a secondary treatment to solid-liquid sepn. after mixing and agitating, subjecting the supernatant liquid thereof to the secondary treatment then to the solid-liquid sepn. and returning part of the settled sludge. CONSTITUTION:Night soil is introduced together with the sludge which is settled in a secondary treatment and is returned from a settling tank 5 into a mixing and agitating tank 1, where the colloidal parts which are frothing substrates are adsorbed on the sludge. The liquid mixture in the tank 1 is introduced into a settling tank 2 where the same is subjected to solid-liquid sepn., whereby the mixture is separated to an upper layer part and a lower layer part. The supernatant liquid in said upper layer part is supplied to a secondary treating tank 4 performing essentially of an aerating treatment for the purpose of the secondary treatment. The colloidal components in the night soil are already removed by the treatments thus far and the frothing is decreased considerably. The secondarily treated liquid from the part 4 is supplied to the tank 5 where the liquid is subjected to solid-liquid sepn., and part of the precipitate of the secondary treatment is returned as the sludge of the secondary treatment to the tank 1.

Description

[Detailed description of the invention] This -193Fi human waste no 11! 1171 method of treating raw human waste to reduce foaming in the tank &: 7+ method for treating raw human waste in SS, after passing the generated urine through a drum screen etc. as a pre-treatment, aerobic treatment is performed. One 10- to 20-fold dilution is performed using the digestion method, activated sludge method, etc.

By the way, in recent years, due to the prevention of wasteful water resources and the implementation of dormitory regulations to regulate the total amount of water, the dilution water saved in human waste treatment Brosene is 111g, and in recent years, non-dilution treatment has become an essential technology.

However, if the dilution water is reduced due to force, there are problems such as decolorization and difficulty in solid-liquid separation, as well as foaming in the aeration tank, which seriously impairs the appearance of the potash. Currently, the solution to this problem of absenteeism is to use expensive antifoaming agents.

This invention solves the problem of the upper age group by eliminating the 1st component of the foaming matrix. The human waste and secondary treatment sludge are mixed and stirred in the pre-treatment RWI, the colloid components are removed, and the foam tube is reduced (9 human waste treatment method t*
The purpose is to provide

Hereinafter, one embodiment of the present invention will be described with reference to Figure No.

The process of an embodiment of the present invention includes a mixing tank 1 for mixing and stirring raw human waste and secondary treatment sludge to improve adsorption of colloids, and a solid-liquid mixture of this mixing tank 1. Separation tank 2 that rots the separation and precipitates the coro 1 component, and this separation tank 2
a sludge thickening tank 3 for concentrating the settled sludge; and the separation tank 2.
A secondary treatment section 4 for treating the supernatant liquid of the upper layer, and a settling tank 5 for precipitating the secondary treatment liquid from the secondary treatment section 4 are arranged.

Next 1: Operation of this invention (I will explain it in two parts.

The raw human waste to be treated is introduced into a mixing agitation tank 1 together with secondary treatment settled sludge (drawn sludge) returned from a settling tank 5, which will be described later. The sludge is mixed with adsorption (colloid component adsorption step). In order to effectively adsorb the colloid components, the residence time of the human waste in the mixing stirring tank 1 is set to 30 minutes to 2 hours. 0 The mixed liquid in the mixing and stirring tank 1 is partially separated in a separation tank 24:4 and divided into an upper layer and a layer containing precipitates such as sludge that have adsorbed colloidal components. (Color 1 component precipitation step) The analytical values of the upper and lower layers are shown in Table 1 below.

Here, in order to effectively achieve the solid-liquid separation effect of the separation tank 2, methane fermentation occurs, and a long residence time is required, resulting in methane fermentation and agitation due to generation of scum.
In order to efficiently precipitate colloidal components, etc., it is recommended to take about 2 to 5 days (if necessary, sludge incineration ash may be added as a sedimentation aid).

Further, a wall 6 is provided in the upper part of the separation tank 2 at the secondary treatment outlet to prevent outflow of scum, short-circuit flow of mixed human waste, and outflow of SS due to upflow.

Next, the first layer of separation tank 2 m&: precipitates and adsorbs 9 colloidal components, and the 9 precipitated sludge is sent to sludge thickening tank 3. I
It also has the safety valve function of the IJII tank 3tf separation tank 2, and the residence time is approximately 12 hours.The culm content is contained, and the settled sludge is separated from the separated liquid and the colloidal components are adsorbed and the 9 surplus sludge is separated.
sludge thickening process). The palm χ is the mixing tank 1 above.
1, and excess sludge is discharged outside.

On the other hand, the supernatant liquid in the upper layer of the separation tank 2 is sent to the secondary processing section 4, which mainly performs secondary treatment of toramenobori air treatment (Secondary Riko S).

When being supplied to the secondary treatment section 4, the colloidal components in the night soil, which is the internal substrate for foaming, are removed from the precipitation process 1 through the adsorption process as described above. Since most of the carbon dioxide is removed during the process, it is a non-dilution process and the C% foaming is significantly reduced. Moreover,
SS in human waste is also removed during the above series of steps, and the amount of organic matter to be treated is reduced, and the colloidal component BO
Since the amount of sludge transferred to D is extremely small, the amount of sludge produced in the secondary treatment section 4 is also reduced. Furthermore, since the SS* input amount and the sludge production amount are reduced, catalytic oxidation is also possible in the secondary treatment s4.Finally, the secondary treatment liquid from the secondary treatment section 4 is further supplied to the settling tank 51, Solid-liquid separation is carried out in this settling tank 5.
Then, a part of the secondary treatment sediment is returned to the mixing and stirring tank 1 as Fi secondary treatment sludge (drawn sludge) (secondary treatment sludge return process) 1, and the rest of the sediment is sent to the secondary treatment section 4. Sent back
Ru. Otherwise, the supernatant liquid is discharged as treated water.

As mentioned above, if the sea urchin sewage treatment method of the present invention is modified, it has extremely excellent effects such as reducing treatment odor and foaming, and reducing the amount of sludge produced.

[Brief explanation of drawings]

The figure shows a flow sheet illustrating one example of the method of the invention. 1... Mixing stirring tank, 2... Separation tank, 3... Sludge thickening tank, 4... Secondary treatment section, 5... Sedimentation tank.

Claims (1)

[Claims] Level 1 human waste to be treated and secondary treatment sewage I described below
i! The COLO 1 component adsorption step involves mixing and stirring the #2 secondary treatment sludge, adsorbing the COLO 1 component in the urine, and solidly separating the COLO 1 component from the mixing machine*. , a colloidal component precipitation step in which the Collo 1F component is precipitated, and a sludge [1] in which the precipitate from this colloidal component precipitation step is
The supernatant Im from the coro 1 component precipitation step was subjected to secondary treatment. A method for treating human waste comprising a secondary treatment sludge return step in which a portion of the secondary treatment sludge is returned to the colloid component adsorption step.