The Methods Of Cyanuric Acid Degradation And Its Industrial Application

Halogenated isocyanuric acid (salt) is one of widely used disinfectant internationally. There will produce large amounts of waste water containing sodium chloride in its production synthesis process. The general content of sodium chloride up to10%. Sodium chloride is the raw material of Chlor-alkali electrolytic. But heterocyclic compound cyanuric acid, exist in waste water also, is easy to generate three nitrogen trichloride in the electrolytic conditions, which can lead to explosion. If the cyanuric acid difficult to separate can broken ring into small molecule inorganic ammonia compounds, and use air blowing to remove it. Then the waste water containing sodium chloride can be used recycling to electrolytic system. It can form the green recycling production. It not only can achieve energy-saving and emission reduction, but also can reduce pollution to environment, It has good economic and social benefits.Cyanuric acid is difficult to decompose because its stability structure. As reported in the literature, the common methods are photochemical degrada-tion, electrochemical processes, γ-ray radiation, efficient bacterium processes, high pressure thermal hydrolysis process and catalytic decomposition. This paper studied the reaction of cyanuric acid broken ring under the influence of several oxidants and oxidation environment. The results show that sodium hypochlorite can decompose cyanuric acid ring because its oxidation. The decompose speed is faster within30minutes. Cyanuric acid residual can reach Smg·L-1. Equivalent to the total ammonium is about2mg·L-1. It suitable for the electrolytic production; The appropriate cyanuric acid concentration is about lOmg·L-1for oxidative decomposition by sodium hypochlorite. The rate of decomposition is more than90%; The mechanism is same for fenton reagent and reactive oxygen decompose cyanuric acid. The three triazine of cyanuric acid have damaged by them. But active oxygen has faster reaction. The concentration of residual cyanuric acid in30minutes the dosing can be close to60minutes the dosing by fenton reagent.Through the improvement of technology for wastewater pretreatment, the cyanuric acid content in the wastewater is greatly reduced. It can be suitable for decompose cyanuric acid using chemical method. The static mixer be introduced in the industrial production device. The wastewater and acid mixing and reaction better because enhancement of mass transfer. And the chlorine gas reacted in system is took out by air. So reaction positive promoted. Cyanuric acid concentration in wastewater reach1.46g·L-1before blowing and dechlorination tower through improved. It is close to the concentration which is1.68g·L-1after the blowing and dechlorination tower by original process. The number of stop production and cleaning is reduced because the cyanuric acid concentration is lower and less crystal. The dechlorination efficiency has enhanced greatly. At the blow-off tower outlet, cyanuric acid concentration decreased to780mg·L-1.The dilute brine which cyanuric acid concentration is less than SOmg·L-1can be gained after the reduction and adsorption process. Based on this, decomposition and deamination tower device increased in the process. It oxidative to damage the cyanuric acid ring and blowing off the ammonia produced. The average concentration of cyanuric acid in dilute brine reduced to4.26mg·L-1. It equivalent to the total ammonium is1.78mg·L-1.It suitable for the electrolytic norm,which is not exceed2mg-L-1. It is realized that the mother liquor wastewater of halogenated isocyanuric acid (salt) circular utilization.