comparison of poly aluminum chloride and chlorinated cuprous for chemical oxygen demand and color removal from kashan textile industries company wastewater

aims: textile wastewaters are the most important health and environmental problems in kashan. this research was aimed to compare the poly aluminum chloride and chlorinated cuprous efficiency for removal of chemical oxygen demand (cod) and color from kashan textile industries company wastewater. materials & methods: this experimental bench scale study in a batch system was conducted on 20 composed wastewater samples collected from kashan textile industries company raw wastewater. during 5 months, in the beginning of every week a day was selected randomly and in the day a composed sample was taken and studied. pac at the doses of 10, 20, 30, 40 and 50mg.l-1 and chlorinated cuprous at the doses of 100, 200, 300, 400 and 500mg.l-1 were applied. the optimum ph also optimum concentration of pac and chlorinated cuprous were determined using jar test. the data was analyzed by spss 16 using descriptive statistics and fisher exact test. findings: the average concentration of cod in the raw textile wastewater was 2801 .56 ± 1398 .29 mg.l-1 . the average cod concentration has been decreased to 1125.47 ± 797.55 mg.l-1 . there was a significant difference between the effects of these two coagulants efficiency (p<0.05). the average cod removal efficiency for chlorinated cuprous and pac was 58.52% and 72.56%, respectively. also, the average color removal efficiency by chlorinated cuprous and pac were 17.23 and 64.45%, respectively. conclusion: pac is more efficient than chlorinated cuprous for both cod and color removal from ktic wastewater.