煤制烯烃废水中苯乙烯的UV/O_3处理技术研究

Study on wastewater treatment technology of styrene from coal to olefin treated by UV/O_3

为考察基于紫外(UV)、臭氧(O_3)氧化处理工艺对苯乙烯和COD的去除效果,以甲醇制烯烃(MTO)装置废水中的苯乙烯为研究对象,分析了初始pH、臭氧投加量、苯乙烯初始浓度以及Al_2O_3-Mn、Al_2O_3-Ti对臭氧氧化苯乙烯去除效果的影响。试验结果表明:在pH=9、臭氧投加量为9 mg/min、苯乙烯初始质量浓度为30 mg/L,单独臭氧氧化降解苯乙烯效果最好,反应60 min后苯乙烯和COD的去除率分别为96.5%和48.1%,Al_2O_3-Mn催化剂催化作用下,臭氧催化氧化苯乙烯废水效果优于单独臭氧,45 min后苯乙烯去除率为99.4%,60 min后苯乙烯去除率达到100%,COD去除率为55.4%。初始pH、苯乙烯初始浓度、过硫酸钠对紫外降解苯乙烯、COD效果的影响试验结果表明:单独紫外在pH=3、苯乙烯初始质量浓度为35 mg/L时去除苯乙烯效果最好,反应120 min去除率达到94%,COD去除率为28%;紫外+过硫酸钠氧化效果优于单独紫外,在pH=7、苯乙烯初始质量浓度为35 mg/L时,反应90 min苯乙烯去除率为99.4%,反应120 min去除率达到100%,COD去除率为30%。臭氧催化氧化工艺较其他3种处理工艺对煤化工废水中苯乙烯的去除具有一定优势。

Taking styrene in coal to olefin MTO process wastewater as the research object,the removal effects of styrene and COD using ultraviolet（ UV） and ozone（ O3） oxidation treatment process were studied.The effects of pH,ozone dosage,styrene initial concentration,Al2O3-Mn and Al2O3-Ti on ozone oxidation of styrene were carried out.The experimental results showed that under the optimal conditions as pH = 9,ozone dosage 9 mg/min,styrene initial concentration 30 mg/L,reaction time 60 min,the removal rates of styrene and COD oxidation by ozone were 96.5% and 48.1% respectively.With the catalysis of Al2O3-Mn catalyst,styrene removal rate of ozone catalyzed oxidation for styrene wastewater was better than ozone only,which reached 99.4% after 45 min,the styrene removal rate could be high to 100% after 60 min,meanwhile,the COD removal rate was 55.4%.The effects of initial pH,styrene initial concentration,sodium persulfate on UV degradation of styrene and COD were studied.The experimental results showed that under the condition as pH = 3,styrene initial concentration 35 mg/L,the removal rate of the styrene and COD removal rate were 94% and 28% after 120 min respectively treated by UV.With the same conditions,the effect of UV＋sodium persulfate was better,as pH = 7 and styrene initial concentration 35 mg/L,the styrene removal rate was 99.4% after 90 min,it could be up to 100% after 120 min,meanwhile,the COD removal rate was 30%.Compared with the other three treatment processes,ozone catalyzed oxidation process had some advantages on treatment of styrene from coal chemical wastewater.