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COD(Chemical oxygen Demand)��ˮ�|(zh��)�O(ji��n)�y�бز��ٵ��Ŀ��京�xָ��һ��l��Ï��̎��ˮ�ӕr��,��mg/L��ʾ,��W��ӳ��ˮ��߀ԭ��|(zh��)��Ⱦ�ĳ̶ȡ��ڙz�y��^��,��ˮ��Cl-�O�ױ��,��Cl-ʹ�Üy��Y(ji��)��ƫ�ߣ��ȵ�COD�Uˮ�Ĝy��ǬF(xi��n)��R��һ��y�},��ڌ��H�O(ji��n)�y�аl(f��)�F(xi��n),��ܶ�N�Uˮ�绯��Uˮ��ζ��Uˮ,��a(ch��n)Ʒ�ӹ��Uˮ��Cl-��ܸ�,��COD�y��Ҫ��Cl-�M��κ��M�Мy��V��h(hu��n)��O(ji��n)�y��Cl-��COD�y��ɔ_��˴��,��Cl-Ӱ푷�ʽ�ͬF(xi��n)�е�Cl-�ɔ_��ɷ��M��U��,��

1 Cl-��COD�y��ĸɔ_

��GB11914-89��ˮ�|(zh��)��W��Ĝy��-��t��⛷��У��_ָ��ˮ��Cl-��^�ߕr��Ҫ��ṯ��΄��,��Ӱ��Ҫ��F(xi��n)��c��

1.1 Cl-��,��(d��o)�y��Y(ji��)��ƫ�ߣ��w��(y��ng)��ʽ�飺

6Cl-+Cr2O72-+14H+→3Cl2+2Cr3-+7H2O

1.2 ��(y��ng)�wϵ�м��y�}��߻��,��Cl-�c�y��(y��ng)��AgCl��ʹ�߻��ж�,��Ӱ표y��Y(ji��)��

2 COD�y��Cl-�ɔ_�ķ��(y��ng)��

��ˮ��M��ϡ��Ǻ��Ч�ķ��֮һ,��Ҳ�ᵽ��Cl-��^1000mg/Lˮ��M��ϡ�,��ڸ��ȵ�COD��ˮ��ϡጱ��(sh��)�^�ߕ�Ӱ표y��ȡ�Ŀǰ,��Cl-�ĸɔ_��ӿ�F(xi��n),��Ҫ�й��}��y�}��˜��У��,��Ț�У��,��]��ⷨ��͝��,��KI-KMnO4��,��G��Մ��ȷ��ȡ�

2.1 ��}��

��}��Ҳ��ṯ�j(lu��)�Ϸ�,��Ǉ��Cl-�ķ��,��HgSO4��Cl-�ڱ΄��HgSO4�cCl-��|(zh��)��10��1��,��˷��Cl-�|(zh��)��С��200mg/L�rЧ��@��,��Cl-��Ⱥܸߕr�y��Y(ji��)��߀��ƫ�ߣ��`��S��Cl-��Ӷ��,��HgSO4��Є��,��ҏUҺ�еĹ��}��y̎��ҕ��h(hu��n)��a(ch��n)��Ⱦ,��ʹ�V��W�ߌ��o��o��Ⱦ�y��о�,��

2.2 �y�}��

�y�}��AgNO3��AgCl��ȥ��Cl-Ӱ푵ķ��m��Cl-�|(zh��)��ȳ��^10000mg/L��ˮ��,��ԓ��ͨ��ЃɷN��ʽ��һ�N��A(y��)̎��r��AgNO3,��ȡ��Һ�y��CODֵ��˷��ҪAgNO3��m��,��ʹCl-��ȫ��Ҳ��^��,��P[1]��ژ˜ʷ��Ļ��A(ch��)��y�к�Cl-��˷��(y��ng)�wϵ��,��ұ��˹��}��Ⱦ,��Y(ji��)��˝M�⡣��һ�N��AgNO3��KCr(SO4)2��Cl-��ڱ΄�,��KCr(SO4)2��^��Cl-�l(f��)��(y��ng),��

�y�}��ʹ��F�ص��y�}��ʹ�y��ɱ��,��ˌ��y�Ļ��Ǻ��б�Ҫ�Ե�,��һ��ȱ�c��AgCl��r��ͨ�^��ʹˮ��ЙC��pʧһ��֣�ʹ�y��Y(ji��)��ƫ��,��

2.3 �˜��У��

�˜��У��Ĳ��E��Ʋ�ͬCl-��ȵ��Ȼ��c�˜��y��CODֵ,��L��COD-Cl-�˜��Ȼ��ȡ�ɷ��ͬˮ��,��һ�݌�Cl-��M��ڱΜy��CODֵ,��ӛ��COD��,��һ�ݜy��x�Ӻ��ژ˜��ϲ��(y��ng)��CODֵ,��ӛ��CODCl-��tCOD��cCODCl-��ֵ��ԓ��Ʒ��挍CODֵ,��

�˜��У��ʹ�ù��}��y�},��Эh(hu��n)��Ժ͹�(ji��)�s�ԣ��ǌ��x�ķ��,��ϼ[2]��ͨ�^��C��@�N��ȫ��ķ��,�c��ՓCl-��ȫ��r��ĵ��ஔ,��Cl-��99%��ϣ�COD�Č��yֵ�c��Hֵ��õ�һ��,��ڸ��Ҳ��õķ��,��l��Ĳ�ͬ��ʹ��Cl-��̶Ȳ�ͬ,��˲�ͬ��L�ƵĘ˜��M��ͬ,��ʹ��@�úܷ��2.4 �Ț�У��

��r��һ��b��,��ɵ�Cl2��(d��o)��NaOH��Һ��,��ʹ��Na2S2O3�˜��Һ�ζ��ĵ�Na2S2O3��Q��,��Cl-��У��ֵ,��H�UˮCODֵ��COD��^ֵ�cCl-��У��ֵ�Ĳ�ֵ��ԓ��m��x�Ӻ��С��20000mg/L,��COD��30mg/L�ĸ��ȏUˮ�Ĝy��,��о��Y(ji��)��10��Ҍ�COD75.5mg/L��208mg/L,��x�ӝ�Ȟ�3000mg/L��16000mg/��Ă��y(t��ng)һ��Ʒ�M�Мy��,��҃�(n��i)��˜�ƫ��2.8%��3.6%֮�g;��g��˜�ƫ��3.2%��7.8%֮�g[3]��ԓ��Ҫ��r�ǳ��м�,��t��`��,��

2.5 �ܷ��ⷨ

��ԭ��]��y��COD��ˮ�е�Cl-��Cl2��_��Һƽ��r,��Cl-�㲻��ٱ��,��ʹ��m��?sh��)��ڱ΄��t��Ԝy��Ʒ��CODֵ,��c�˜ʷ��,��ԓ��ĽY(ji��)��и��ߵĜʴ_�Ⱥ;��ܶȡ��־��[4]�Ȍ��͌��Hˮ�ӵĜy��Y(ji��)��,��ܷ��ⷨ��ȏUˮ��COD�ʴ_��^��,��COD��100mg/L��1000mg/L,��x�ӝ��С��10000mg/L�r��ԓ��`��≤4.2%,��ܷ��ĕr��,��ԓ��һ��Σ�U�ԣ��һ��Ҫ�_��İ�ȫ,��

2.6 KI-KMnO4��

�ډA�ԗl��,��KMnO4��Uˮ�е��|(zh��)��ʣ��KMnO4��KI߀ԭ,��Na2S2O3�˜��Һ�ζ�,��Na2S2O3��ĵ��Q��,��Ķ��õ�һ��CODֵ��Ǒ�(y��ng)��ԓ��cK2Cr2O7��Ĝy��ֵ��ͬ,��һ��ֵK,��ֻ��֪��@��ֵK��Ɍ��KI-KMnO4��y�õ�CODֵ�M�ГQ�㼴��,��ԓ��m��Cl-��ڎ��f��ʮ�f��ÿ��ďUˮ,��Ҫ�y��Kֵ��˺ܷ��,��

2.7 �G��Մ��ȷ�

ˮ��е�Cl-��Һ�w��HCl��w��ʽጷų��,��G��Մ��ճ�ȥ��Ȼ��y��CODֵ,��ԓ��Ĝʴ_�Ⱥ;��_��c�˜ʷ��ȟo�@��,��ⷽʽ��ͬ��΢��,��

3 �Y(ji��)Փ

�C�Ͽ�֪,��Cl-��ˮCODӰ푵ķ��Էփ��:ˎ��μ��͜y��V��W��ڷ��ĸ��M��˺ܶ๤��,��o��o��Ⱦ,��ݜʴ_�ķ��l(f��)չ��N��ڌ��H��(y��ng)�Õr��һ��m�÷��;��,��߀�д��Mһ��ĸ��M��,��ӏ��N��֮�g�Ľ��B͸��̽��µ��Cl-�ɔ_�ķ��һ��x��

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