KR20090052946A - Manufacture and procedure to make clean waste water containing oil and salt - Google Patents

Abstract

The present invention relates to a method for treating wastewater containing a large amount of an oil component (seawater and various cleaning water, etc. introduced into an oil and mixed with an oil, etc.) and to preventing odor generated from the wastewater. The present invention is a technology for treating wastewater containing a large amount of oil and salts generated in ships and marine facilities, oxidizing the emulsified oil using ozone, and oil and various pollution in the wastewater using a flocculating settling agent. By reducing materials (SS, BOD, COD, ABS, etc.), and to a wastewater treatment method and apparatus for environmentally safe discharge to the ocean.

According to the present invention, it is possible to preserve the marine environment and the safety of workers by discharging the bottom wastewater containing a large amount of oil components without the use of various pollutant removal devices environmentally safe and discharged without the external emission of odor.

Wastewater treatment, ozone treatment, flocculation sedimentation

Description

Wastewater treatment apparatus and wastewater treatment method including oil components and salts {Manufacture and procedure to make clean waste water containing oil and salt}

The present invention relates to a method for treating wastewater containing a large amount of an oil component (sea water and various cleaning water, etc. which have flowed into a ship and mixed with oil or the like).

Conventionally, various oil components and contaminant removal devices, such as emulsifiers, flotation devices, activated carbon filters, and odor adsorption systems, have been used for wastewater treatment.

Specifically, in order to remove the oil component on the surface of the waste water, the oil is removed by using a gravity type oil separator separating the skimmer, and an emulsion breaker is added to separate the fine oil component emulsified in the waste water. After removal, the oil is removed secondarily using a floating oil separator (IAF or DAF). In addition, in order to remove various contaminants dissolved / dispersed in the waste water, various devices such as flocculant input, reaction tank, precipitation tank, aeration tank, pH adjustment tank, activated carbon filtration device, and biological treatment method are installed and operated in combination.

The biological treatment method of the prior art is difficult to apply to the waste water (sea water, food treatment water, etc.) containing salt, and the treatment efficiency is also low. In addition, as described above, when using a plurality of devices, the operating cost is high, and it is not an appropriate treatment method in a small and medium-sized wastewater treatment plant.

That is, the conventional wastewater treatment method is expensive to install and maintain, and in particular, does not sufficiently remove oil and solids (SS), anionic surfactants (ABS), BOD, and COD, and remove odors and turbidity. There is also a low problem.

The present invention is to improve the conventional wastewater treatment method described above, and to provide a wastewater treatment method and apparatus for environmental treatment of wastewater containing a large amount of oil and containing salt.

Specifically, the present invention aims to simplify the wastewater treatment process, effectively reduce oil and various contaminants contained in the wastewater, and to remove odor generating sources from the wastewater.

The present invention provides a waste water treatment apparatus comprising: a gravity oil separation tank for removing suspended oil; An ozone input tank for oxidizing oil components and pollutants of waste water by directly adding and reacting ozone in the waste water; And it provides a waste water treatment apparatus comprising a precipitation tank for precipitating contaminants by inputting and stirring the flocculating settling agent.

The oil / water separation tank may include a supply pump for supplying wastewater.

A waste oil storage tank may be included in which oil suspended from the oil / oil separation tank is transferred.

It may include a transfer pump for transferring the wastewater from the oil-water separation tank to the ozone input tank and the coagulation sedimentation tank from the ozone input tank.

The ozone injection tank may include a pipe for supplying ozone to the wastewater.

The coagulation sedimentation tank may include a pipe for injecting coagulation sedimentation agent into the waste water surface.

The flocculation settling tank may include an agitator for stirring the flocculation settler.

A sludge storage tank for treating sludge generated in the ozone input tank and the coagulation sedimentation tank may be included.

The present invention also provides a wastewater treatment method comprising the steps of: (a) removing suspended oil; (b) oxidizing the oil components and contaminants of the wastewater by introducing and reacting ozone in the wastewater; And (C) precipitating contaminants by adding and stirring the flocculating precipitant.

In the step (a), the wastewater is preferably supplied at a flow rate of 0.5m / s ~ 1m / s.

The oil suspended in the step (a) is preferably collected, and periodically transported to the waste oil storage tank.

In step (b), ozone is preferably added at a concentration of 5 g to 20 g / hr.

In the step (b), ozone is preferably added directly into the waste water.

In step (c), the flocculent precipitation agent is preferably introduced into the waste water surface.

The present invention is an apparatus and method for removing odor generated early by oxidizing ozone directly in the wastewater containing a large amount of oil, and oxidizing contaminants to coagulate and settle.

Wastewater treatment method according to the present invention can be operated by shortening the wastewater treatment process containing a large amount of oil, it can be applied to wastewater containing salt that is difficult to biological treatment using microorganisms. According to the present invention, it is suitable for a small and medium-sized wastewater treatment plant by reducing the operating cost according to the simplification of the process, and it is possible to improve the wastewater treatment process without greatly changing or establishing an existing treatment facility. In addition, in terms of wastewater discharge, it is possible to minimize the impact on the water quality by lowering the emission concentration of the surfactant, which is a problem in using the conventional emulsifying agent, and in particular by lowering the emission concentration of BOD and COD.

The present invention is a method that can be applied to a small wastewater treatment plant by adopting a simple and inexpensive method.

In the wastewater treatment method of the present invention, the oil component floating on the surface of the wastewater is removed from the specific gravity difference to remove the oil component contained in the wastewater. Next, by oxidizing / removing the emulsified oil and various contaminants by adding / contacting and reacting ozone (O ₃ ) with strong oxidation in the wastewater. Thereafter, a method of precipitating the oxidized residual organic material with a coagulant precipitation agent is used.

The wastewater treatment apparatus of the present invention is a gravity oil-separation tank that removes oil components (oil) suspended in the wastewater firstly, and the ozone is directly injected into the wastewater including oil and salt as an oxidant exhibiting a strong effect on sterilization and deodorization. Ozone injection tank to oxidize oil and other contaminants contained in emulsion in waste water, and finally remove coagulation and precipitation of oxides and other contaminants generated from ozone injection. It consists of three stage treatment tank of flocculation settling tank.

In addition, the sludge generated from the waste oil storage tank, the secondary ozone input tank, and the third flocculation sedimentation tank, which are transported for recycling of the oil removed from the first gravity oil-water separation tank, is transferred, and the disposal process includes a storage tank.

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 is a view showing the configuration of a wastewater treatment apparatus using ozone and flocculation sedimentation agent according to the present invention.

First, the wastewater introduced into the wastewater storage tank 1 is introduced into the gravity type oil-water separation tank 3 through the supply pump 2. At this time, the inflow rate is composed of oil-water separation tank so that the average flow rate can be in the range of about 0.5m / s ~ 1m / s in consideration of the floating speed of oil. The floated oil is collected by the skimmer and is periodically transported to the waste oil storage tank 5.

Next, the waste oil from which the floating oil is removed is transferred to the ozone input tank 6 through the transfer pump 4. In the ozone injection tank 6, ozone generated from the ozone generator 7 is aerated using a pipe (or plastic hose) which is immersed under the water in the ozone injection tank 6. At this time, the concentration of ozone is 5 ~ 20g / hr. The input method is direct injection into the waste water, and the input time is determined according to the pollution level of the waste water, but usually 10 to 20 minutes, 6 to 12 hours are input at intervals of 30 minutes to 1 hour rest. A pause is necessary to prevent the ozone generator from overheating. The emulsified oil and contaminated organic substances contained in the waste water in the ozone input tank are oxidized / bleached by ozone, so that the color of the waste water becomes black to cloudy milky, and the odor generated from the waste water is also removed.

The ozonated wastewater is transferred to the coagulation sedimentation tank 9 through the transfer pump 8. Coagulant precipitant is introduced through the water surface using a powder chemical injection device, and uses a flexible pipe (or hose) equipped with a flotation device to prevent the powdered medicine from scattering. The flocculating precipitant is a mixture containing montmorillonite, activated clay, and activated carbon as the main raw materials.

If the agitator 10 is installed to stir the injected chemicals, the agitator 10 is sufficiently stirred for 10 minutes or more, and a precipitate is generated through the reaction of the contaminant and the flocculation chemical.

After stopping the stirring and settling for 30 minutes to 1 hour, the sludge is separated from the contaminated supernatant and the bottom of the coagulation sedimentation tank.

The sludge generated in the ozone input tank 6 and the coagulation sedimentation tank 9 is transferred to the sludge storage tank 13 through a pipe connected to the lower part of the water tank and is periodically processed.

As described above, the wastewater subjected to ozone treatment and sedimentation of pollutants is significantly improved in odor and turbidity, and low concentrations of various pollutants can be discharged to the ocean.

<Example>

Wastewater used in this experiment is bottom wastewater collected from merchant ships and fishing boats in Wando and Sokcho ports. The bottom wastewater is a mixture of engine cooling seawater, cleaning water, engine lubricating oil and fuel oil, and other domestic wastewater introduced into the vessel, and is usually taken out of the vessel every two to six months.

Experiments were carried out on a device of the same type as the accompanying drawings. In ozone was introduced at a concentration of 5g / 10 min. The concentration of hr In 50 minutes was added 12 times with an interval of rest (ozone input time 2 hours), flocculation agent is 2,000ppm (waste water 2kg per 1m ³⁾ against waste water . The flocculation sedimentation drug was used in the composition of Table 1 below.

Water quality analysis results are shown in Table 2 below.

(Unit: mg / ℓ)

As described in the table, the wastewater treatment method and apparatus according to the present invention showed an excellent effect on the removal of various contaminants.

In addition, in the case of odor, the odor was removed from 13 ppm before treatment to 0 ppm after treatment as a wastewater treatment according to the present invention.

1 is a block diagram of a wastewater treatment method including an oil component using ozone and flocculation sedimentation agent according to the present invention

2 is a wastewater photograph treated using the present invention

<Description of Drawing>

1: wastewater storage tank 2: supply pump

3: oil / water separation tank 4: transfer pump

5: waste oil storage tank 6: ozone injection tank

8: Transfer pump 9: Coagulation sedimentation tank

10: stirrer 13: sludge reservoir

Claims (14)

A wastewater treatment apparatus comprising: a gravity oil separation tank for removing suspended oil; An ozone input tank for oxidizing oil components and pollutants of waste water by directly adding and reacting ozone in the waste water; And a sedimentation tank for depositing contaminants by inputting and stirring the flocculating precipitant. The wastewater treatment apparatus according to claim 1, wherein the oil / water separation tank includes a supply pump for supplying wastewater. The wastewater treatment apparatus according to claim 1, further comprising a waste oil storage tank through which oil suspended from the oil / water separation tank is transferred. The wastewater treatment apparatus according to claim 1, further comprising a transfer pump for transferring wastewater from the oil / water separation tank to the ozone input tank and the coagulation sedimentation tank from the ozone input tank. The wastewater treatment apparatus according to claim 1, wherein the ozone injection tank includes a pipe for supplying ozone to the wastewater. The wastewater treatment apparatus according to claim 1, wherein the flocculation settling tank includes a pipe for injecting the flocculation settling agent into the wastewater surface. The wastewater treatment apparatus according to claim 1, wherein the coagulation sedimentation tank comprises a stirrer for stirring the coagulation sedimentation agent. The wastewater treatment apparatus according to claim 1, further comprising a sludge storage tank for treating sludge generated in the ozone input tank and the coagulation sedimentation tank. In the wastewater treatment method, (a) removing the suspended oil; (b) oxidizing the oil components and contaminants of the wastewater by introducing and reacting ozone in the wastewater; And (C) precipitating contaminants by inputting and stirring the flocculating precipitant. 10. The method of claim 9, wherein in the step (a), wastewater is supplied at a flow rate of 0.5 m / s to 1 m / s. 10. The method of claim 9, wherein the oil suspended in step (a) is collected and periodically transferred to a waste oil storage tank. 10. The method of claim 9, wherein in step (b), ozone is introduced at a concentration of 5 g to 20 g / hr. 10. The method of claim 9, wherein in step (b), ozone is introduced directly into the wastewater. 10. The method of claim 9, wherein in step (c), the flocculating sedimentant is introduced into the wastewater surface.

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