{"id":13639,"date":"2024-01-22T07:54:35","date_gmt":"2024-01-22T07:54:35","guid":{"rendered":"https:\/\/naturalstarvina.com\/overtreatment-of-cod-in-wastewater\/"},"modified":"2025-08-01T03:19:26","modified_gmt":"2025-08-01T03:19:26","slug":"overtreatment-of-cod-in-wastewater","status":"publish","type":"page","link":"https:\/\/naturalstarvina.com\/en\/overtreatment-of-cod-in-wastewater\/","title":{"rendered":"Overtreatment of COD in Wastewater"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"13639\" class=\"elementor elementor-13639\">\n\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-2689eaf7 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"2689eaf7\" data-element_type=\"section\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;,&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-89ec24d\" data-id=\"89ec24d\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-294f3524 elementor-widget elementor-widget-elementskit-heading\" data-id=\"294f3524\" data-element_type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"elementskit-heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<div class=\"ekit-wid-con\" ><div class=\"ekit-heading elementskit-section-title-wraper center   ekit_heading_tablet-   ekit_heading_mobile-\"><div class=\"elementskit-section-subtitle  \">\n\t\t\t\t\t\tOur Services\n\t\t\t\t\t<\/div><h1 class=\"ekit-heading--title elementskit-section-title \"><span><span>Overtreatment of COD in Wastewater<\/span><\/span><\/h1><div class=\"ekit_heading_separetor_wraper ekit_heading_elementskit-border-divider elementskit-style-long\"><div class=\"elementskit-border-divider elementskit-style-long\"><\/div><\/div><\/div><\/div>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-52904b0e elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"52904b0e\" data-element_type=\"section\" data-settings=\"{&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-4cba03b1\" data-id=\"4cba03b1\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-1726bb66 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"1726bb66\" data-element_type=\"section\" data-settings=\"{&quot;ekit_has_onepagescroll_dot&quot;:&quot;yes&quot;}\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-2c3890cb\" data-id=\"2c3890cb\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-717b3efa elementor-widget elementor-widget-text-editor\" data-id=\"717b3efa\" data-element_type=\"widget\" data-settings=\"{&quot;ekit_we_effect_on&quot;:&quot;none&quot;}\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p><!-- wp:paragraph --><\/p>\n<div data-page-id=\"EdL4d49IdolK4Fx9cj4lYbOhgjg\" data-docx-has-block-data=\"false\">\n<div class=\"ace-line ace-line old-record-id-doxlgM0JwrENAvVVdRlu74hpe7b\">\n<div data-page-id=\"O3Egd3Xp7o8tvWxmgo4lsIP0gJg\" data-docx-has-block-data=\"false\">\n<div data-page-id=\"H7PcdSPtloARB4xLSPGlB8Uzgfl\" data-docx-has-block-data=\"false\">\n<h2 class=\"heading-3 ace-line old-record-id-doxlgRkbPHq74PX1j0zA0xx9Ltd\"><span style=\"color: #000000;\">What is COD in wastewater?<\/span><\/h2>\n<div class=\"ace-line ace-line old-record-id-doxlgQIL91alVeJDFoOdHJCGVxg\"><span style=\"color: #000000;\">COD (Chemical Oxygen Demand), also known as chemical oxygen demand, is an important parameter for evaluating wastewater quality. COD measures the amount of oxygen required to oxidize organic matter in wastewater with inorganic oxidants.<\/span><\/div>\n<div class=\"ace-line ace-line old-record-id-doxlg4CgfJP3LgvYgjNI3s1V39W\"><span style=\"color: #000000;\">The higher the COD content of wastewater, the greater the amount of organic matter in the water, the decomposition process needs more oxygen. Therefore, COD is an important indicator to assess the pollution of water.<\/span><\/div>\n<div class=\"ace-line ace-line old-record-id-doxlgQqQpgMc2xGX35XTrk0VSib\"><span style=\"color: #000000;\"><strong>The Impact of COD on the Environment<\/strong><\/span><\/div>\n<ul class=\"list-bullet1\">\n<li class=\"ace-line ace-line old-record-id-doxlgbZl934lE9wg5JlHBdXeBBb\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Wastewater with high COD content will reduce the amount of dissolved oxygen in the water. This adversely affects aquatic organisms, even causing hypoxia, killing fish.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlgIamUJgkepmTdWq4d9ibNde\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">High COD increases the activity of anaerobic bacteria, producing toxic decomposition products such as H2S, CH4 that pollute the environment.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlg34azLSrB2D4RSYrU53nD1y\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">High COD wastewater when discharged into rivers and lakes wastes oxygen in the receiving water, reducing the quality of surface water.<\/span><\/div>\n<\/li>\n<\/ul>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"aligncenter size-full wp-image-13652\" src=\"http:\/\/naturalstarvina.com\/wp-content\/uploads\/2024\/01\/Vuot-chi-so-COD-trong-nuoc-thai-cong-nghiep.jpg\" alt=\"V\u01b0\u1ee3t ch\u1ec9 s\u1ed1 COD trong n\u01b0\u1edbc th\u1ea3i c\u00f4ng nghi\u1ec7p\" width=\"1920\" height=\"1080\" srcset=\"https:\/\/naturalstarvina.com\/wp-content\/uploads\/2024\/01\/Vuot-chi-so-COD-trong-nuoc-thai-cong-nghiep.jpg 1920w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2024\/01\/Vuot-chi-so-COD-trong-nuoc-thai-cong-nghiep-300x169.jpg 300w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2024\/01\/Vuot-chi-so-COD-trong-nuoc-thai-cong-nghiep-1024x576.jpg 1024w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2024\/01\/Vuot-chi-so-COD-trong-nuoc-thai-cong-nghiep-768x432.jpg 768w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2024\/01\/Vuot-chi-so-COD-trong-nuoc-thai-cong-nghiep-1536x864.jpg 1536w\" sizes=\"(max-width: 1920px) 100vw, 1920px\" \/><\/p>\n<h2 class=\"heading-3 ace-line old-record-id-doxlg7hd1EMnVamuFWbGM24nppe\"><span style=\"color: #000000;\">COD analysis method in wastewater<\/span><\/h2>\n<ul class=\"list-bullet1\">\n<li class=\"ace-line ace-line old-record-id-doxlgxJkzbaF4srNaXhIMSoniAc\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">The method of using dichromate: based on the principle of oxidation of organic matter by potassium dichromate solution at high temperature (150 \u2103), in concentrated sulfuric acid medium containing silver ion as catalyst and mercury salt.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlgWTKhlV4sitkODM3Ta9zEMb\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">The method of COD analysis by the device: using a COD analysis device that automatically measures the light absorption of the solution after the reaction.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlglfFLeOgbSEFn4gwFkq2vIg\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">COD chemical method: using pre-packaged COD measuring chemicals with standardized ingredients.<\/span><\/div>\n<\/li>\n<\/ul>\n<div class=\"ace-line ace-line old-record-id-doxlgfsH9ryDmdRmsa8o1T7PqBB\"><span style=\"color: #000000;\"><strong>What causes increased cod in wastewater?<\/strong><\/span><\/div>\n<ul class=\"list-bullet1\">\n<li class=\"ace-line ace-line old-record-id-doxlgLXobRTTbms6afwKIpIg6Dc\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Domestic wastewater contains a lot of organic matter, grease, food waste is thrown away causing an increase in COD.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlgniifLV7vglIfRSC45F9npc\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Wastewater from factories and enterprises contains toxic organic substances such as phenol, ammonium, increasing COD.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlgnGXUeur2MfSIv69b1IbBfY\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">The anaerobic decomposition of organic matter in sewage sludge, landfill also produces high COD leachate.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlgyYWk6eBStrqlUej0zzuOLg\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Excessive occurrence of algae, plankton due to excess nutrient status also increases COD in water sources.<\/span><\/div>\n<\/li>\n<\/ul>\n<h2 class=\"heading-3 ace-line old-record-id-doxlg5fsEDIPMolgVRbL7EOedrT\"><span style=\"color: #000000;\">COD treatment technology in wastewater<\/span><\/h2>\n<ul class=\"list-bullet1\">\n<li class=\"ace-line ace-line old-record-id-doxlgNXZCnW1CSvAuLRf0Qgebeg\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Biological treatment (activated sludge, biofiltration methods, pond sedimentation&#8230;) helps bacteria break down organic matter efficiently.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlg1aGbKKqxrqdmRGSHigdpwb\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Chemical treatment with chlorine, ozone, advanced oxidation helps break down organic molecules.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlgV67P6j5qrkJSqsZNBNQlJb\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Membrane treatment, activated carbon adsorption removes organic matter.<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlg2Y4d4FOEo0brvT3LoXiB9c\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Combining multiple technologies to improve COD processing efficiency.<\/span><\/div>\n<\/li>\n<\/ul>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-10126 lazyload\" data-src=\"http:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1.png\" alt=\"V\u01b0\u1ee3t ch\u1ec9 s\u1ed1 COD trong n\u01b0\u1edbc th\u1ea3i c\u00f4ng nghi\u1ec7p\" width=\"1200\" height=\"1200\" data-srcset=\"https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1.png 1200w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1-300x300.png 300w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1-1024x1024.png 1024w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1-150x150.png 150w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1-768x768.png 768w\" data-sizes=\"(max-width: 1200px) 100vw, 1200px\" src=\"data:image\/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==\" style=\"--smush-placeholder-width: 1200px; --smush-placeholder-aspect-ratio: 1200\/1200;\" \/><noscript><img decoding=\"async\" class=\"aligncenter size-full wp-image-10126\" src=\"http:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1.png\" alt=\"V\u01b0\u1ee3t ch\u1ec9 s\u1ed1 COD trong n\u01b0\u1edbc th\u1ea3i c\u00f4ng nghi\u1ec7p\" width=\"1200\" height=\"1200\" srcset=\"https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1.png 1200w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1-300x300.png 300w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1-1024x1024.png 1024w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1-150x150.png 150w, https:\/\/naturalstarvina.com\/wp-content\/uploads\/2023\/11\/4-1-768x768.png 768w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/noscript><\/p>\n<h2 class=\"heading-3 ace-line old-record-id-doxlgjTUV8uo7OTFBn8Wm81BaHh\"><span style=\"color: #000000;\">COD regulation in wastewater according to QCVN<\/span><\/h2>\n<div class=\"ace-line ace-line old-record-id-doxlg8exaDue8efJyEOUfe3TYMb\"><span style=\"color: #000000;\">According to QCVN 40: 2011 \/ BTNMT, the allowable limit of COD in industrial wastewater is stipulated:<\/span><\/div>\n<ul class=\"list-bullet1\">\n<li class=\"ace-line ace-line old-record-id-doxlgVcfP5LXVc74lujoKQP44KQ\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Wastewater flows directly to the receiving source: 100-200 mg\/L<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlgrb5KVQpENYfHz2rvSbuCoe\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Wastewater flows into municipal sewer systems: 300-500 mg\/L<\/span><\/div>\n<\/li>\n<li class=\"ace-line ace-line old-record-id-doxlgmRQuur0Rm6mcqy21nBA78e\" data-list=\"bullet\">\n<div><span style=\"color: #000000;\">Wastewater discharged into the general sewer of production, business and service areas: 300-600 mg\/L<\/span><\/div>\n<\/li>\n<\/ul>\n<div class=\"ace-line ace-line old-record-id-doxlgFVFQfnaVuonRx6i1b1EWec\"><span style=\"color: #000000;\">Thus, the monitoring and treatment of COD in wastewater is essential to protect the water environment. Modern treatment technologies need to be applied to ensure that the COD concentration is up to standard before being discharged to the water source.<\/span><\/div>\n<h2 class=\"heading-3 ace-line old-record-id-doxlgjRFLU2UUr0ee7LgKy2wsic\"><span style=\"color: #000000;\">Excessive COD treatment unit in wastewater<\/span><\/h2>\n<div class=\"ace-line ace-line old-record-id-doxlgAguGrpoA6RrKAD7p8QZqef\"><span style=\"color: #000000;\">Natural Star Vina is a Korean company specializing in consulting, designing and constructing reputable wastewater treatment systems with many years of experience in deploying hundreds of different large and small projects. All systems that Natural Star designs and operates have reached the COD index in wastewater according to the Ministry of Natural Resources and Environment regulations QCVN 40: 2022 \/ BTNMT before discharging waste into licensed water sources.<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p><!-- \/wp:paragraph --><\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Our Services Overtreatment of COD in Wastewater What is COD in wastewater? COD (Chemical Oxygen Demand), also known as chemical oxygen demand, is an important parameter for evaluating wastewater quality. COD measures the amount of oxygen required to oxidize organic matter in wastewater with inorganic oxidants. The higher the COD content of wastewater, the greater [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_monsterinsights_skip_tracking":false,"footnotes":""},"class_list":["post-13639","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/naturalstarvina.com\/en\/wp-json\/wp\/v2\/pages\/13639","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/naturalstarvina.com\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/naturalstarvina.com\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/naturalstarvina.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/naturalstarvina.com\/en\/wp-json\/wp\/v2\/comments?post=13639"}],"version-history":[{"count":13,"href":"https:\/\/naturalstarvina.com\/en\/wp-json\/wp\/v2\/pages\/13639\/revisions"}],"predecessor-version":[{"id":19744,"href":"https:\/\/naturalstarvina.com\/en\/wp-json\/wp\/v2\/pages\/13639\/revisions\/19744"}],"wp:attachment":[{"href":"https:\/\/naturalstarvina.com\/en\/wp-json\/wp\/v2\/media?parent=13639"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}