Treatment Technology On Production Wastewater Of Efficient Non-Sulfur Polymerization Inhibitor

As a polymerization inhibitor,2-sec-butyl4,6-dinitrophenol (DNBP) is widely used in pesticides, herbicides and olefin-based aromatic compounds. A mass of highly toxic and less degradable nitro phenol wastewater are generated in the process of DNBP production; it has caused not only serious damage to the environment, but also inhibits the sustainable development of enterprises. Currently there is little research on DNBP wastewater treatment. In this paper, extraction and distillation was used for treatment, initial understanding about the power of entire process was achieved in experiments in order to determine the conditions, it provides scientific basis for the following pilot experiment and industrial treatment.Extraction was used to treat DNBP wastewater. Recycling organic matter of wastewater using extraction may reduce the loss of raw materials; on the other hand, it may reduce the organic matter content, such as the COD, the chromaticity. In the extract process, many aspects’influence can be reviewed such as the extractant, the diluents, the extract time, the phase ratio and the initial pH value. By that, the best extraction condition of wastewater can be ascertained. This method is described as following:taking tributyl phosphate as extractant, coal oil as diluent, the extractant content being70%, the extract time being30min; the extract phase ratio(oil-water ratio)is controlled as1:5; using the raw water pH as the extract value directly, choosing two levels. After the extraction the waste water COD elimination rate reaches80%, the chromaticity from10000falls to2000, and the apparent color from the reddish brown discolored to the shallow yellowish brown. In this paper, the experiment process of extractant regeneration and the stripextraction process are also studied. The basic parameters are determined. If the content of NaOH is20%and the oil-water ratio is3:1, the stripextraction effect is best. The extracting agent performance is perfectly in this experiment. According8times stripextraction, it is proved that the technique has well anti-fatigue strength.In this paper, electrochemical oxidation of DNBP wastewater was studied. In the experiment, the main factor of degradation, such as oxidation time, current density, temperature were investigated to optimize the better electrolysis condition. It obtained that electrolysis time of7h, the current density of80mA/cm2, initial pH=1. Stable COD removal rate reached59.2%. DNBP wastewater was degraded effectively in Ta/BDD electocode oxidation process, current density and electrolysis time have important influence on oxidation process, and temperature effect is smaller.Distillation was also studied for wastewater treatment. Separating and recycling organic matter of wastewater by the different boiling point may reduce the content of COD and chromaticity. By atmospheric distillation and vacuum distillation experiments, the optimal distillation conditions for wastewater treatment are ascertained. In distillation process, firstly atmospheric distillation is carried out; adjust the pH of effluent to7by alkalizing, and then carry on the vacuum distillation, reflux ratio is controlled as2, alkali content being2.6g/L. The COD of effluent is below60mg/L, it has reached the secondary discharge standards of "Integrated Wastewater Discharge Standard"(DB12/356-2008) of Tianjin. It proves that distillation is feasible to such wastewater; it can be promoted to nitrophenol wastewater.