System and method for removing organic compounds from waste water by oxidation

Abstract

The present invention relates to a process and a system for processing waste water containing organic compounds. The system includes a UV / ozone oxidation removal module, or one or more removal modules connected in series whereas such a serial connection can be continuous or discontinuous. A UV / ozone oxidation removal module mainly includes an ozone generator, an ozone injector, an ozone dissolution tank, an ozone decomposition device, a UV reaction tank, a recycling pipeline. The efficiency of the UV / ozone oxidation removal module is controlled by the recycling ratio, the ozone concentration, and the intensity of UV light.

Description

FIELD OF THE INVENTION [0001] The present invention relates to the oxidation removal of organic compounds from the waste water generated by industrial processes related to the fabrication of semiconductor devices, LCDs, etc., particularly to a process and a device for removing organic compounds from a waste water by oxidation by injecting ozone into the waste water and irradiating the water with UV light. BACKGROUND OF THE INVENTION [0002] Due to its geographical environment, Taiwan area has an insufficient amount of water and has difficulty in developing new water resources. In the mean time, the amount of water use in different sectors increases continuously by the year. Particularly, the expansion in the semiconductor production capacity increases the water consumption in multiples. As a result, the companies in the Science Parks in the Taiwan area face a severe pressure on water shortage and water restriction. This makes the maladjustment of water resources become a noticeable p...

AI Technical Summary

Benefits of technology

[0008] an ozone dissolution tank for receiving a resulting ozone / waste water mixture from said ozone injector and providing a residence time for ozone to perform an oxidation reaction with the organic compounds in said to-be-treated water;

Problems solved by technology

Due to its geographical environment, Taiwan area has an insufficient amount of water and has difficulty in developing new water resources.

Particularly, the expansion in the semiconductor production capacity increases the water consumption in multiples.

As a result, the companies in the Science Parks in the Taiwan area face a severe pressure on water shortage and water restriction.

This makes the maladjustment of water resources become a noticeable problem.

However, at this limit, the plants face a problem of a recovery ratio lower than 70%.

However, if the TOC recovery threshold is increased, the organic removal techniques (e.g. activated carbon adsorption, reverse osmosis filtration, bio-bed filtration, etc.) used by the industry will lose their functions due to the limits of the techniques which are in the range of 0.5˜5 ppm.

In an activated carbon adsorption technique, the competitive adsorption / desorption reactions of the active carbon will cause the processed water having a too wide variation of the water quality.

In a reverse osmosis filtration technique, the TOC removal ratio is low and bacteria are liable to grow.

And in a bio-bed filtration technique, functions of the bio-bed are liable to be lost due to a large fluctuation of the water quality.

Having their existing technical bottlenecks in need of being solved, the abovementioned techniques are helpless in the treatment of waste water with a higher content of organic compounds, and can not achieve the demand of increasing the process recovery ratio.

This is a huge blow to an industry which faces an ever increasing water consumption due to the construction of new plants to achieve an economical production scale while facing a tight domestic water supply and difficulties in creating new water resources.

So far UV / Ozone has not been successfully and effectively applied on the removal of high concentration of organic compounds from waste water of the semiconductor and LCD processes.

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