Study On Pretreatment Of The Dye Wastewater By Low-Temperature Plasma Combined With Ozone

We use the combination technology of ozone and low-temperature plasma to treat 7 kinds of simulated dyeing water making it meet recycling requirements. It utilizes the synergism of the two methods to produce more hydroxyl radicals. Hydroxyl radical can react lively with dye, which can increase the removal rate of pollutants.The pH maintain at 9.5～10.0, Comparing with the efficiency of different dyestuffs' CODcr degradation in the same reaction time, we confirm that the chemical structure of molecule, the property and position of the functional groups all obviously affect the efficiency of CODcr degradation. Typically, under the same number of aromatic ring, the efficiency of the CODcr degradation: anthraquinone dye > single azo dye > dual azo dye.Comparing with the efficiency of different dyestuffs' chroma degradation in the same reaction time, all the efficiency of chroma degradation are more than 99% after reacting 15 minutes. This technology has good applicability on dye wastewater treatment, and the degradation of chroma has little effect on the molecular structure of dyestuff. In other words, anthraquinone structure, the structure of the Single-azo and dual-azo dyes all achieve good effeciency of degradation.After the investigation of ozone available efficiency, it indicates that the most economical treatment time for disperse blue 2BLN is 10 minutes. It can be attained from the economical analysis that the advanced treatment of ozone technology can save cost of 2.97 RMB per stere water.This paper confirmed that the combination technology of ozone and low-temperature plasma could improve the biodegradability of dye wastewater, speed of degradation, high treatment efficiency, less energy consumption, no secondary pollution, good applicability and so on. So it is advantageous for the industrialization promotion and suitable in the pretreatment for dye waste water with hard degradation.