5. Introduction of practical example

5-1 Seawater circulation process in exhibition tank of aquarium

(Practical example of Special AOP device)
The water in an aquarium tank that is used to raise different species of fish is highly important and it would cost a lots of money and need a lot of efforts to keep it clean and safe. It is especially very costly because the high quality water of the sea has been transported from a long distance.
A unique AOP device (Brand name, Uzon) uses ozone gas that is generated by Ultraviolet lamp in an ultraviolet water sterilizer. In another word, it is a UV/AOP device that uses a combination of UV + Ozone. It is a unique device because it consists of a single UV lamp as it is shown in the Fig 2.

In 2004, one of the aquariums in Japan, carried a cross examination of the UV water sterilizers and this unique Uzon AOP device equipped with the same type of lamps on a well admired water in the aquarium thank. . The results revealed that while the UV sterilizer showed an anticipated result it failed to prevent the water turning yellow due to fish secretion. On the other hand, Uzon prevented the sea water from coloring and maintained limpid and sterilized water.
That particular aquarium has gained great advantages by adopting this unique AOP device (Uzon) in the existing process line regarding:
1) Sterilization of pathogenic bacteria
2) Maintenance of clear water
3) Reduction of supply water

The water in most of the aquarium tanks range from few to several tens of cubic meter, and the largest one up to 50m3  , but in any of them a device with a single 95W UV lamp is efficient enough to maintain the sea water both the chromatically and limpidly.
In future, the use of UZON in other aquariums is expected.

Fig.�]2 Internal Structure of UZON	Photo 4 Exhibition tank purification process state

5-2 Examples of advanced oxidation treatment for groundwater

In many cases, iron, manganese component, ammonium nitrogen and organic matter are dissolved into groundwater.
Usually the methods of filtration, addition of sodium hypochlorite and activated carbon adsorption are used. However, depending on pollution concentration density the quantity of active carbon must be increased and sometimes the running cost becomes so high that these methods cannot be used.
In such cases, UV/AOP can reduce the quantity of activated carbon as well as improving the quality of treated water. Also successfully reduces the running cost.
Fig. 3 shows the process flow. Ground water is pumped up, pass through pre-process sand elimination prior to UV and sodium hypochlorite process. First, filter tower is used to eliminate the separated iron and manganese components, and then activated carbon to remove the final residual.
The data on processed water quality of example given in this descript are shown in table 2.treatment data of this example is given in table 2 and resulting water from these processes are shown in Fig 5.
In this regard, the life span of activated carbon without UV/AOP was only 3 months while using AOP increased it to 12 month.

Photo 5 Treatment of Water in Well	Photo 6 Ground Water Purification Device, External Appearance

		Running cost			Reduced cost per year 20 million yen
		Before installing the photo-oxidation device	After installation
	Water rent	About 24 million yen	About 12 million yen
	Activated carbon	2 million yen X 3 times/year = 6 million yen	2 million X 1 time/year		The cost can be recovered within approximately one year from the date of installation
	Hypochlorous acid	600,000 yen X 12 months = 7.2 million yen	350,000 yen X 12 months = 4.2 million yen
	Administration cost	Replacement of activated carbon, etc. = 1.8 million yen	Replacement of activated carbon, etc. = 1 million yen

6. Summary

This article explains the characteristic and practical examples of using UV light in advanced oxidation process (UV/AOP). It is expected to develop into an indispensable technology by applying the effective characteristics of UV/AOP,
(1) Advanced treatment
(2) Energy and space saving
(3) Controlling the inhibition of secondary waste during processing. (Sludge free)
results, from environmental point of view, energy saving recycling and from production point of view, for an era of enhanced water process conformity.