KR19990050101A - Zeolite-Containing Continuous Batch Reactor - Google Patents

Abstract

The present invention relates to a continuous batch reactor to which a granular zeolite is added and a wastewater treatment method using the reactor. Using the zeolite-containing continuous batch reactor according to the present invention can reduce the amount of scum generated in the initial stage of operation compared to the conventional reactor, it is possible to improve the removal rate of organic matter. In addition, due to the adsorption of ammonia nitrogen, nitrification proceeds rapidly, and the total nitrogen removal rate can be improved. Suspended solids also continued to exhibit excellent removal rates due to the stability of the microorganisms attached to the zeolite.

Description

Zeolite-Containing Continuous Batch Reactor

The present invention relates to a continuous batch reactor to which granular zeolites are added and to a wastewater treatment method using the reactor, in particular a wastewater treatment method containing nitrogen and toxic substances.

Continuous batch reactors have recently been known as efficient reactors capable of rapidly evolving with the automation of control equipment to remove organics and nitrogen components from waste water. In particular, this reactor has the advantages of low facility cost, easy operation, etc. can be carried out reaction and precipitation separation in one reactor, the application to various wastewater treatment is being studied. In addition, continuous batch reactors are being used in biological treatment processes that can efficiently remove nitrogen and organics present in wastewater, and studies to increase the retention of microorganisms in order to speed up the removal of contaminants in the wastewater have been conducted. . As part of this, studies have been conducted to increase the activity of adherent microorganisms by adding a medium such as polyurethane in a continuous batch reactor. Further, in order to remove nitrogenous components present in the wastewater, studies have been carried out such as first adsorbing ammonia nitrogen with zeolite and then introducing the wastewater into the biological reactor.

However, biological treatment is a technique for treating wastewater using microorganisms, so when toxic substances and high concentrations of contaminants are introduced, treatment efficiency rapidly deteriorates and it takes a long time to recover. In particular, when biological wastewater treatment technology is applied to industrial wastewater in which various toxic substances exist, the initial operation period for reaching normal operation is lengthened. Therefore, there is a need for an improvement in biological wastewater treatment technology using a continuous batch reactor that overcomes the above disadvantages.

The present invention provides a continuous batch reactor capable of efficiently treating biologically high concentrations of organic matter and wastewater containing nitrogen. The present invention also provides a wastewater treatment method using the continuous batch reactor.

1 is a schematic diagram of addition of zeolite to a continuous batch reactor.

2 is a schematic representation of a zeolite network deposited in a continuous batch reactor.

3 is a schematic view showing a continuous batch reactor used in this example.

Figure 4 is a schematic diagram showing the operating cycle of the continuous batch reactor carried out in this embodiment.

<Explanation of symbols for main parts of the drawings>

11: stirrer

12: diffuser

13: zeolite net

14: granular zeolite

The continuous batch reactor according to the invention is characterized in that it comprises a zeolite network of granular zeolites in the reactor.

1 is a form of a continuous batch reactor with zeolite added according to the present invention. The continuous batch reactor according to the invention comprises a zeolite network 13 in a reactor equipped with a stirrer 11 and an aeration device 12. According to the present invention, the agitator 11 is used to create anoxic and anaerobic conditions to induce a denitrification reaction, thereby removing organic matter, and using the aeration device 12 to cause residual organic matter removal and nitrification. The zeolite network 13 can reduce scum generation by adsorbing ammonia nitrogen and adsorbing toxic organic substances during initial operation, and can quickly induce organic matter removal and nitrification.

Therefore, when treating wastewater containing biologically high concentrations of organic matter and nitrogen, nitrogen can be efficiently removed by increasing the rate of nitrification which is first required and promoting denitrification. In particular, when the biological treatment process is applied to industrial wastewater, it is reported that nitrification is greatly inhibited by various toxic substances present in industrial wastewater, but zeolite which is capable of adsorbing ammonia nitrogen and various toxic substances is added at the beginning of operation. This can increase the efficiency of the bioreactor.

Hereinafter, the present invention will be described in more detail with reference to Examples. In this example, the process of treating petrochemical wastewater containing organic matter and nitrogen using a continuous batch reactor was exemplified, and the removal rate of organic matter and the nitrogen removal rate were investigated by comparing the reactor with and without zeolite. .

<Example>

A cylindrical reactor made of acrylic material (see Fig. 3) with a height of 30 cm and an effective volume of 2.5 liters was used, and the chemical oxygen demand was 450 mg / L, total nitrogen content 95 mg / L, pH 8.0 , Wastewater containing 400 mg / L alkalinity was tested.

The wastewater was poured into the reactor and air was injected at 2 liters / minute using an air pump and acidic rocks. The wastewater in the reactor was mixed using a stirrer (150 rpm) and the temperature in the reactor was maintained at 25 ° C. using a constant temperature water circulator. As shown in FIG. 4, the operating conditions of the reactor were 12 hours / cycle using an automatic control device, 2 hours of total anoxic inflow, 6 hours of preaerobic reaction, 1.5 hours of post anoxic condition, 0.5 hours of post-aerobic reaction, 1 hour of precipitation, Discharge and settling were performed for 1 hour, and 0.83 liters per cycle were discharged and operated with a hydraulic retention time of 1.5 days.

The sample collected in the reactor was analyzed by filtration with filter paper (TOYO, 5A, 110 mm). As for the analysis items, concentrations of COD and nitrogen sources such as TKN, NO ₂ -N, and NO ₃ -N were measured according to standard methods. In addition, the concentration of dissolved oxygen in the reactor was measured in the reactor using an oxygen electrode (YSI model 58).

In the same manner as described above, the results of treating the petrochemical wastewater using the continuous batch reactor to which the zeolite was added according to the present invention are shown in Table 1 in comparison with the case of the conventional continuous batch reactor without the zeolite. As can be seen from these results, the continuous batch reactor according to the present invention showed excellent removal rate of organic matter such as chemical oxygen demand, biochemical oxygen demand and nitrogen removal rate. In particular, ammonia nitrogen was removed almost completely in zeolite-containing continuous batch reactors to improve the subsequent removal of total nitrogen. In addition, in the case of the suspended solids, the zeolite-containing continuous batch reactor showed better removal rate due to the stability of the microorganisms adsorbed on the zeolite.

On the other hand, as a result of operating two laboratory-scale continuous batch reactors for petrochemical wastewater containing hardly decomposable substances, the zeolite-containing continuous batch reactor according to the present invention showed excellent organic and nitrogen removal rates even during the initial acclimation period. There was little generation. In addition, even after several months of operation after addition to the reactor, excellent organic matter, color, and nitrogen removal rate were shown.

According to the present invention, the reactor in which the zeolite was added to the continuous batch reactor showed excellent organic and nitrogen removal rates, especially in the initial operation, compared to the conventional continuous batch reactor, and the organic and nitrogen were continuously excellent by biological regeneration without regenerating the zeolite. The removal rate is shown.

Operation Results of Zeolite-Containing Continuous Batch Reactors and Comparative Reactors Analysis item characteristic Influent Zeo continuous batch reactor treated water Conventional Continuous Batch Reactor Treated Water Chemical oxygen demand Concentration (mg / ml) 450 50 75 Removal rate (%) 89 83 Biochemical Oxygen Demand Concentration (mg / ml) 110 5 8 Removal rate (%) 95 2.5 Ammonia nitrogen Concentration (mg / ml) 90 0.2 or less 93 Removal rate (%) 99.8 97.2 Total nitrogen Concentration (mg / ml) 95 14 30 Removal rate (%) 85.3 68.4 Suspended solids Concentration (mg / ml) 50 3 5 Removal rate (%) 90 80

In addition to the efficient initial adsorption of ammonia nitrogen present in the wastewater, the continuous batch reactor according to the present invention is biologically regenerated by nitrification-denitrification to exhibit a continuous pollutant removal effect.

Claims (2)

A continuous batch reactor for wastewater treatment comprising a stirrer, an aeration device, and a zeolite network containing granular zeolites. A method of biologically treating wastewater containing nitrogen and toxic substances using a continuous batch reactor, wherein the zeolite is introduced into the reactor at the beginning of the treatment.