{"id":247084,"date":"2026-06-24T17:27:46","date_gmt":"2026-06-24T17:27:46","guid":{"rendered":"https:\/\/swefc.unm.edu\/home\/centralized_resource\/calculating-chlorine-dosage-feed-rate-and-residual-chlorination-estimator\/"},"modified":"2026-06-24T17:27:46","modified_gmt":"2026-06-24T17:27:46","slug":"calculating-chlorine-dosage-feed-rate-and-residual-chlorination-estimator","status":"publish","type":"centralized_resource","link":"https:\/\/swefc.unm.edu\/home\/centralized_resource\/calculating-chlorine-dosage-feed-rate-and-residual-chlorination-estimator\/","title":{"rendered":"Calculating Chlorine Dosage, Feed Rate, and Residual &#8211; Chlorination Estimator"},"content":{"rendered":"\n<p id=\"isPasted\"><strong>Calculating Chlorine Dosage, Feed Rate, and Residual<\/strong><\/p><p>Chlorine is a useful disinfectant for wastewater treatment and can be introduced in liquid, gas, or solid form. The required chlorine dosage for wastewater treatment depends on a variety of factors including the chlorine demand of the wastewater, the availability of de-chlorination, detention time, and regulatory limits for chlorine residuals in a systems wastewater discharge. To calculate the chlorine demand of your system, a system needs to record their feed rates of chlorine and analyze the residual chlorine in their system after chlorine treatment. The chlorine residual (mg\/L) is subtracted from the chlorine dosage (mg\/L) to determine the chlorine demand (mg\/L). Chlorine residuals can be measured utilizing a simple colorimetry test. De-chlorination is typically required when using chlorine for disinfection due to the hazard chlorine presents to wildlife and public health. Dechlorination is accomplished through a variety of processes, including aeration and sulfur dioxide, which is often favorable, because a 1:1 ratio is often sufficient for dechlorination. A chlorine residual of 0.1 mg\/L can be hazardous to fish, and a chlorine residual of 0.3 mg\/L can be fatal to fish. Wastewater operators typically determine their required chlorine dosage\/ feed rate by continuously testing their chlorine residual using a colorimetry test and adjusting their feed rate as needed. The SWEFC has created a spreadsheet to assist operators in estimating their required feed rate, required chlorine&nbsp;dosage, and likely chlorine residual.<\/p><p><strong>Chlorination Estimator<\/strong><\/p><p>The Chlorination Estimator is a simple excel tool that operators can use to calculate their chlorine needs. By inputing a few simple wastewater parameters operators can calculate the chlorine feed rate needed to achieve a desired chlorine dosage, the required chlorine dosage required based on the desired chlorine residual and known chlorine demand, and likely chlorine residual.<\/p><p><br><\/p><p><a href=\"https:\/\/swefc.unm.edu\/home\/wp-content\/uploads\/2024\/12\/Chlorination-Estimator.xlsx\"><strong>Download the Chlorine Estimator Here<\/strong><\/a><\/p><p><a href=\"https:\/\/swefc.unm.edu\/home\/wp-content\/uploads\/2024\/12\/Calculating-Chlorine-Dosage-Feed-Rate-and-Residual.pdf\"><strong>Download Calculating Chlorine Dosage, Feed Rate, and Residual Here<\/strong><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Calculating Chlorine Dosage, Feed Rate, and Residual Chlorine is a useful disinfectant for wastewater treatment and can be introduced in liquid, gas, or solid form. The required chlorine dosage for wastewater treatment depends on a variety of factors including the chlorine demand of the wastewater, the availability of de-chlorination, detention time, and regulatory limits for [&hellip;]<\/p>\n","protected":false},"featured_media":247085,"template":"","centralized_category":[265],"centralized_topic":[310],"ww_resource_type":[331],"class_list":["post-247084","centralized_resource","type-centralized_resource","status-publish","has-post-thumbnail","hentry","centralized_category-treatment","centralized_topic-treatment","ww_resource_type-excel"],"acf":[],"_links":{"self":[{"href":"https:\/\/swefc.unm.edu\/home\/wp-json\/wp\/v2\/centralized_resource\/247084","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/swefc.unm.edu\/home\/wp-json\/wp\/v2\/centralized_resource"}],"about":[{"href":"https:\/\/swefc.unm.edu\/home\/wp-json\/wp\/v2\/types\/centralized_resource"}],"version-history":[{"count":0,"href":"https:\/\/swefc.unm.edu\/home\/wp-json\/wp\/v2\/centralized_resource\/247084\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/swefc.unm.edu\/home\/wp-json\/wp\/v2\/media\/247085"}],"wp:attachment":[{"href":"https:\/\/swefc.unm.edu\/home\/wp-json\/wp\/v2\/media?parent=247084"}],"wp:term":[{"taxonomy":"centralized_category","embeddable":true,"href":"https:\/\/swefc.unm.edu\/home\/wp-json\/wp\/v2\/centralized_category?post=247084"},{"taxonomy":"centralized_topic","embeddable":true,"href":"https:\/\/swefc.unm.edu\/home\/wp-json\/wp\/v2\/centralized_topic?post=247084"},{"taxonomy":"ww_resource_type","embeddable":true,"href":"https:\/\/swefc.unm.edu\/home\/wp-json\/wp\/v2\/ww_resource_type?post=247084"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}