JPS596993A - Biological treatment of waste water containing organic substance - Google Patents

Abstract

PURPOSE:To contrive to make various devices for water disposal small in size, by making waste water of medium high concentation composed of similar pollutants in waste water of medium low concentration having passed through the second conditioning anaerobic tank, and sending the mixture from a separator through the second aerobic tank to a precipitation-separating tank. CONSTITUTION:Waste water of medium low concentration is sent from the first condition anaerobic tank 1 to the first aerobic tank 2, a separator 3, the second aerobic tank 4 and a precipitation-separating tank 4, while waste water of medium high concentration composed of pollutants equal or similar to those of the waste water of medium low concentration is discharged from the second conditioning anaerobic tank 5, mixed with the waste water of medium low concentration flowing out of the first aerobic tank 2 and sent to the separator 3, the second aerobic tank 4 and the precipitation tank 5. The waste water contg. the activated anaerobic sludge flowing out of the first conditioning anaerobic tank 1 is charged together with a newly formed aerobic sludge returned from the precipitation-separation tank 5 by a sludge pump 8 in the first aerobic tank 2 in which aerobes are activated but anaerobes are latent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for biological treatment of wastewater containing organic substances, which is capable of treating medium-high concentration wastewater without dilution.

As mentioned in Shukan, concentrated wastewater with extremely high pollutant concentration, such as raw human urine, boiled broth and blood juice from seafood processing, has always been difficult to dispose of.
After being retained for around 0 days to generate methane gas and collecting it, all of this desorbed liquid is treated using the activated sludge method. Since it is not suitable for treating high-concentration wastewater ((Usually, the undiluted wastewater is diluted with diluted water several tens of times before being treated with the viscous sludge method), biological treatment is first performed. The general process of the activated sludge method is as shown in Figure 1.
The diluted activated sludge process wastewater is temporarily stored in the adjustment tank AVC, and after performing operations such as homogenizing the liquid, adding nutrients, and adjusting the pH as necessary, a certain amount of it is continuously aerated. Water is supplied to tank B, and the water is allowed to stay in this aeration tank B for a certain period of time, and the waste water is decomposed by acid f and arsenic by aerobic bacteria activated by the air sent from blower C, resulting in sludge (
After forming 70 ng), the wastewater is sent together with this sludge to a sedimentation separation tank to separate the settled sludge and supernatant liquid,
The supernatant liquid is discharged outside the system as treated water, a portion of the sludge is returned to the aeration tank B by the sludge pump E for circulation, and the remaining sludge (d) is passed through the sludge dehydrator FK and then discharged from the system. In such a conventional activated sludge method, the amount of raw wastewater in the activated sludge method increases due to the addition of dilution water, which increases the size of equipment such as aeration tank B and complicates operation. Moreover, since a large amount of aeration is required in the aeration tank B, there is a drawback that the power cost of the blower C increases and the operating cost increases.

This blueprint was made in view of our own circumstances, and it is important to dilute medium-high concentration wastewater. The purpose of this method is to reduce the size of various devices used in the processing process, simplify operation, and further reduce operating costs and processing time by making the process easier.

The feature of this invention is that after the medium-low concentration wastewater is sequentially sent from the first adjustment anaerobic tank to the first aerobic tank, the same or similar medium-to-low concentration wastewater is passed through the second adjustment anaerobic tank. Mixed with medium and high concentration wastewater consisting of pollutants, the mixture is sent from the separator to a zero-sedimentation tank via a second aerobic tank, and all aerobic sludge separated after inspection of the settling vessel is discharged from the first adjustment anaerobic tank. It is biologically treated in the wastewater treatment circulation system where it is mixed with medium and high concentration wastewater and returned to the first aerobic tank, and mixed with the liquid part from the separation device and returned to the second aerobic tank. .

The method of this invention will be explained in detail below with reference to FIG.

14f. In this invention, medium-high concentration wastewater and medium-low concentration wastewater consisting of the same or similar pollutant components are, for example, medium-high concentration wastewater such as boiling liquid, blood, etc. in the marine product processing process of mackerel and sardines, and general process wastewater. Wastewater is referred to as medium- and low-concentration wastewater.

In addition, if raw human waste is considered medium-high concentration wastewater, general city sewage and diluted human waste fall under medium-low concentration wastewater. Furthermore, the middle and high concentration wastewater 1 includes methane fermentation desorbed liquid in addition to the untreated undiluted solution wastewater as mentioned above.

Wastewater includes seafood processing wastewater, stocked raw wastewater, agricultural processing wastewater,
All wastewater containing other organic substances can be treated by the 2U method of the present invention, regardless of its type.

Among the bacteria that act in the wastewater treatment circulation system of this invention, aerobic bacteria include Zoogloea bacteria and other yeasts, and anaerobic bacteria include oily anaerobic bacteria that have some aerobic properties. Bacteria belonging to the genus Lactobacillus, Pediococcus, Streptococcus, Bacillus, etc. are essential, and other lateral anaerobic bacteria are essential. It may also be included. When facultative anaerobic bacteria contain bacteria belonging to the genus Lactobacillus, specific effects described below are produced. These aerobic bacteria and anaerobic bacteria are injected into the science department in advance at the start of operation of the wastewater treatment circulation system (1111), and from then on, those that have grown naturally in the science department are used. 〇Medium and low concentration wastewater is sent from the first adjustment anaerobic tank 1 to the first aerobic tank 2, the separation device 3, the second aerobic tank 4, and the sedimentation separation tank 115, and is composed of the same or similar pollutant components as the medium-low concentration wastewater. The medium-high concentration wastewater is mixed with the wastewater that has exited the first aerobic tank 2 from the second adjustment anaerobic tank 6 and then sent to the separation device 3 and the second
It is sent to an aerobic tank 4 and a sedimentation separation tank 5.

The medium- and low-concentration wastewater is collected in the first adjustment anaerobic tank l, where necessary operations such as equalization of liquid properties, addition of nutrients, and pH adjustment are performed, as well as air sent from the blower 7. is aerated and stirred by This aeration agitation causes the anaerobic bacteria including facultative anaerobic bacteria living in the first adjusted anaerobic tank 1 to proliferate, and the anaerobic sludge in which these anaerobic bacteria are exposed is completely generated. Since it provides even and rapid dissolved oxygen in the wastewater, the aeration per unit pollutant can be reduced to a weak aeration that is usually about one-tenth or less of the aeration mass in the first aerobic tank 2. It has been proven empirically and experimentally. This is because if a larger amount of aeration is performed, although the wastewater is sufficiently agitated, the oily anaerobic bacteria become inactive and anaerobic sludge is produced h fx .

The medium and high concentration wastewater is collected in the second adjustment anaerobic tank 6, where, like the medium and low concentration wastewater, the wastewater is adjusted as necessary and aerated and agitated, and the anaerobic bacteria including facultative anaerobic bacteria are removed. Explicit anaerobic sludge is produced.

The wastewater containing anaerobic sludge in which anaerobic bacteria have become apparent, leaving the first adjustment anaerobic tank 1, is transferred from the sedimentation separation tank 5 to the sludge pump 8.
1: The sludge is mixed with the returned aerobic sludge in which the aerobic bacteria have become apparent and the anaerobic bacteria have become latent, and the sludge is mixed with the new sludge and put into the first aerobic tank 2. The mixing ratio of the two is such that the solids concentration is equal or slightly higher than the aerobic sludge gold. What are these two different types of sludge? Lzotr
Among these contradictory physicochemical properties, Kulonka and Noah/Derwalska showed an increase in affinity between aerobic and anaerobic sludge, as well as a species difference between the two sludges. A strong cohesive force between the two sludges results from the additive effects such as the formation of inter-polymer bonding reactions and the adhesive force due to the mucous membrane formed by the aerobic bacteria. Due to the effect of taking in dissolved components due to the progress of flocculation in this strong flocculation mountain range, new sludge containing both aerobic and anaerobic bacteria is generated, and the purification effect of wastewater is promoted. be. Incidentally, aerobic sludge and anaerobic sludge generated from wastewater containing the same or similar pollutant components either have a strong flocculation rate as shown in L, or, on the contrary, have a strong flocculation rate as shown in L. It has been experimentally determined that there is no cohesive force between aerobic sludge and anaerobic sludge. This is not a cohesive reaction or simply due to Coulomba and van ter Waals forces, but also indicates the existence of a bonding reaction between polymers in certain persimmons.

The newly generated sludge is transferred to the first aerobic tank 2.
By aeration and agitation, aerobic sludge becomes aerobic sludge in which aerobic bacteria are exposed and anaerobic bacteria are latent.
The sludge is mixed with wastewater containing anaerobic sludge from the second regulating anaerobic tank 6, and is then input into the separation device 3 together with the sludge produced for the same reason as described above. Ru. The mixing ratio of the two is such that the solids concentration is equal or a little more aerobic sludge is mixed. The generation of this new sludge promotes the purification effect of the wastewater containing anaerobic sludge discharged from the second regulating anaerobic tank 6. In addition to the above-mentioned microorganism flocculating operation, if necessary, an organic or inorganic flocculant may be added to the separation device 3 in order to further improve the processing efficiency. Further, this new sludge is separated from the liquid part in the separator 3, and then separated into solid and liquid by the sludge dehydrator 9, the solid part is discharged outside this wastewater treatment circulation system, and the liquid part is separated into the sedimentation separation tank 5. The aerobic sludge returned by the sludge pump 8 is mixed and then introduced into the second aerobic tank 4.

Note that the separation device 3 is not limited to the illustrated sedimentation tank type, but also includes devices using other physical or mechanical means. Due to aeration and agitation in the second aerobic tank 4,
In the second aerobic tank 4, the aerobic bacteria become apparent and the aerobic sludge with latent anaerobic bacteria becomes active and is then sent to the sedimentation separation tank 5 where it is separated into 10M liquid and aerobic sludge. . This supernatant liquid is discharged as treated water to the outside of this wastewater treatment circulation system, and the aerobic sludge is returned to the first aerobic tank 2 and the second aerobic tank 4 by the sludge pump 8 as described above.

In addition, the aerobic sludge in the above explanation contains aerobic bacteria, including 1 box of Zoogloea bacteria, which were introduced into the science system before the start of operation of this wastewater treatment circulation system, or which naturally multiplied afterwards. , in which anaerobic bacteria including facultative anaerobic bacteria are latent, in the first aerobic tank 2, second aerobic tank 4, and second adjusted anaerobic tank 6, as well as in the first adjusted anaerobic tank 1. The aeration and agitation is also carried out by the air that is sent in by the blower 7, but it goes without saying that aeration and agitation by other means may be used in place of this.Furthermore, the first Adjusted anaerobic tank 1 and 21st i!l adjusted anaerobic tank 6
In this case, anaerobic bacteria, including anaerobic bacteria, introduced before the start of operation, are introduced into the inflow and outflow of wastewater through aeration and agitation.
They continue to grow and produce anaerobic sludge,
It is possible to provide a wastewater treatment circulation system in which aerobic sludge separated due to various reasons of wastewater pollution level a is returned to the 1st:A regulating anaerobic tank 1 and the second regulating anaerobic tank 6. In the case of this system, the anaerobic bacteria that are latent in the aerobic sludge can become apparent and multiply in the first adjustment anaerobic tank 1 and the second adjustment anaerobic tank 6 by the aeration and agitation described above. be. Therefore, in this system, the first key [114! l and second
The wastewater discharged from the adjusted anaerobic tank 6 contains anaerobic sludge in which anaerobic bacteria inhabit, in which anaerobic bacteria have become manifest and aerobic bacteria have become latent. Similar to the system described above, the aerobic sludge returned from the sedimentation separation tank 5, in which aerobic bacteria are exposed and anaerobic bacteria are latent, is mixed to form a solid sludge.

In the two wastewater treatment circulation systems mentioned above, when facultative anaerobic bacteria and lactic acid bacteria are included, the action of the lactic acid bacteria further increases the strong sludge flocculation effect, and at the same time The production of sludge is promoted, and the progress of the putrid state accompanied by the proliferation of rotting fine teeth under anaerobic conditions in the first and second adjusted anaerobic tanks 1 and 6 is delayed, and therefore, the generation of putrid odor is also prevented. It has the effect of being

As is clear from the following explanation, the method of this invention is effective in treating aerobic bacteria contained in medium and low concentration wastewater treated under aerobic conditions, which become apparent, and anaerobic sludge that is latent. Wr sludge produced by mixing sludge with anaerobic sludge in which anaerobic atomization contained in medium-high concentration wastewater consisting of the same or similar pollutant composition as the medium-low concentration wastewater has become evident, The pollutant components contained in medium-high concentration wastewater are rapidly purified. Therefore, when treating medium- and high-concentration wastewater as in the past, it is no longer necessary to dilute it several tens of times, making it possible to downsize each device and simplifying operation. Furthermore, since the amount of aeration in each aerobic tank and each adjusted anaerobic tank can be significantly smaller than in the conventional activated sludge method, operating costs can be reduced. Furthermore, the sludge produced by the separator 3 can be effectively used for various feed fertilizers.

Examples of this invention will be described below.

Wastewater: Medium and low concentration wastewater (general process wastewater in mackerel and rockfish processing processes, low BOD concentration 6000ppm, 450t/day.

Medium and high concentration wastewater (boiled liquid from mackerel and sardine processing processes) BOD concentration 50,000 ppm, l Ot/day.

Medium and high concentration wastewater (liquid removed from methane fermentation of straight needles in the mackerel and sardine processing process) BOD concentration 12,000
ppm, 10 t/day.

The amount of air required to treat the BOD concentration IKg in the conventional activated sludge method has been reduced to 50m/
As BODKg, (450tX6Kg+10tX50Kg+10tX12
Kg)
The number of blowers required for this aeration amount is 30KW x 5 units.In the method of this invention, the aeration amount in the second anaerobic tank is aerated air volume and the inlet BOD concentration of the first aerobic tank is 11,000 pp.

However, 50% of the sludge will be returned to the first aerobic tank and the second aerobic tank.

Therefore, the required air volume in the first aerobic tank is 690tx.
1. OKgX50m3 + 24 hours ÷ 60 minutes - 24,0m
3/min.

The required air flow M in the first adjusted anaerobic tank C is 1/10 of the air volume in the first aerobic tank, so it is 2.4 r + d'min.O The BOD concentration at the inlet of the second aerobic tank is 450 ppm. The required air volume in the air tank is 920tX0.45Kg
X50m3+-24 hours ÷ 60 minutes = 14.4 m/min O
Total aeration amount = 2.2 m, /min + 24.0 m 4 min + 2.4 m
/min 14, 4m/min = 43. The air blast required for this aeration amount was 30 KW x 2 units, and in this example, a flocculant consisting of 10 ppm of liquid sulfuric acid was used in the separator.

As is clear from the above examples, the amount of aeration in this starting method is less than half that of the conventional activated sludge method. Wastewater cannot be treated as it is, so it must be diluted several tens of times.To do this, it is necessary to install dilution water supply equipment, increase the cost of dilution water, and increase the size of each device due to the increase in wastewater. However, the method of this invention has been able to eliminate all of these drawbacks.

[Brief explanation of the drawing]

FIG. 1 shows a general flow sheet for the conventional activated sludge method, and FIGS. 2 and 3 show examples of flow sheets for the method of the present invention. 1. First adjustment anaerobic tank, 2. First aerobic tank, 3. Separation device, 4. Second aerobic tank, 5. Sedimentation separation tank, 6. Second adjustment anaerobic tank. Patent applicant: Mizu Uchimizu, attorney Mizuhiko Watanabe Procedural amendment (voluntary) May 23, 1980 Commissioner of the Japan Patent Office Kazuo Wakasugi1, Indication of the case, Patent Application No. 115716, 1982, Title of the invention Biological Treatment Method for Wastewater Containing Organic Substances 3, Relationship with the Amendment Case Patent Applicant Name Oshinotsu Food Industry Co., Ltd. 4, Agent Address: Osaka 530 Tel: 06 (361) 38
31 Address 2-21 Tayu-cho, Kita-ku, Osaka (1) Detailed explanation of the invention in the specification column 6, Contents of amendment (11 Detailed explanation of the invention column ■ Page 15, line 3 of the specification Correct “anaerobic lη mud” to “anaerobic bacteria”.

Claims (1)

[Scope of Claims] 1 Between - or (-1 Among medium-high concentration wastewater and medium-low concentration wastewater consisting of similar pollutant components, NFJ medium-low concentration wastewater 1 adjustment anaerobic tank to first aerobic tank in order After the water is sent, it is mixed with the medium-high concentration wastewater that has passed through the second adjustment anaerobic tank and sent from the separation device to the sedimentation separation tank via the second aerobic tank, and the aerobic sludge separated in the sedimentation separation tank is This is a wastewater treatment circulation system that mixes with medium and low concentration wastewater discharged from the first regulating anaerobic tank and returns it to the first aerobic tank, and also mixes it with the liquid part from the separation device and returns it to the second aerobic tank. Then, the first adjustment 1111i
In the aeration tank, aeration and agitation suitable for producing anaerobic sludge in which anaerobic bacteria including facultative anaerobic bacteria are exposed is performed, and the waste water containing this anaerobic sludge is returned from the sedimentation separation tank. Aerobic sludge in which aerobic bacteria including Zoo-gloea bacteria have become apparent and anaerobic bacteria have become latent is mixed to produce sludge, and aerobic bacteria are removed by aeration and agitation in the first aerobic tank. The anaerobic sludge is made into an aerobic sludge in which anaerobic bacteria have become apparent, and the wastewater containing this aerobic sludge is aerated and stirred in a second adjustment anaerobic tank. New sludge is generated by mixing wastewater containing sludge, and the liquid part is separated using a separator. This new sludge is discharged outside the wastewater treatment circulation system, and the liquid part is returned from the sedimentation separation tank. After activating aerobic bacteria by mixing with the aerobic sludge and aerating it in the second aerobic tank, the wastewater containing this aerobic sludge is sent to the sedimentation tank to separate the aerobic sludge. The supernatant liquid and all treated water are discharged to the outside of the wastewater treatment circulation system, and the aerobic sludge is returned to the first aerobic tank and the second aerobic tank as described above. 2. A method for biological treatment of wastewater containing organic substances. 2. Wastewater containing organic substances according to claim 1, wherein the facultative anaerobic bacteria are facultative anaerobic bacteria belonging to the genus Lactobacillus. Biological treatment method. 3 Among medium-high concentration wastewater and medium-low concentration wastewater consisting of the same or similar pollutant components, the medium-low concentration wastewater is divided into the first adjustment anaerobic tank and the first aerobic tank. After the water is sent in sequence, it is mixed with the medium-high concentration wastewater that has passed through the 2A anaerobic tank, and sent from the separation device to the sedimentation separation tank via the second aerobic tank, and all the aerobic sludge separated in the sedimentation separation tank is The medium and low concentration wastewater discharged from the first regulating anaerobic tank is mixed with the wastewater and returned to the first aerobic tank, and the liquid part from the separation device is also mixed and returned to the second aerobic tank, and the liquid is mixed with the wastewater and returned to the second regulating anaerobic tank. and a wastewater treatment circulation system that also returns the wastewater to a second regulating anaerobic tank, wherein the first regulating anaerobic tank is suitable for producing anaerobic sludge in which anaerobic bacteria including facultative anaerobic bacteria are exposed. At the same time, the aerobic sludge containing this anaerobic sludge and the aerobic sludge in which aerobic bacteria including Zooglaea (200-gloea) bacteria become apparent and anaerobic bacteria become latent are returned from the wastewater containing this anaerobic sludge and the sedimentation separation tank. The mixture is mixed to produce sludge, which is then aerated and agitated in the first aerobic tank to produce aerobic sludge in which aerobic bacteria are exposed and anaerobic bacteria are latent. Anaerobic sludge, in which anaerobic bacteria including facultative anaerobic bacteria have become apparent, is generated by aeration and agitation in the tank.All of the collected wastewater is mixed to form a new sludge, and the liquid portion is separated by a separation device. The new sludge is separated and discharged to the outside of the wastewater treatment circulation system, and the liquid portion is mixed with the aerobic sludge returned from the sedimentation separation tank and aerated and stirred in the second aerobic tank to produce aerobic bacteria. After the aerobic sludge is fully activated, the aerobic sludge and gold-containing wastewater are sent to the sedimentation separation tank, and the aerobic sludge and lIJ@shiichihi liquid are discharged as treated water to the outside of the wastewater treatment circulation system. The sludge is returned to the first aerobic tank and the second aerobic tank, and is also distributed and returned to the first adjustment anaerobic tank and the second conditioning anaerobic tank. Biological treatment methods for wastewater, including; 4. The biological treatment method for wastewater containing organic substances according to claim 3, wherein the facultative anaerobic bacteria are oily anaerobic bacteria including bacteria of the genus Lactobacillus.