Jar Tests Fine‐Tune Your Plant's Performance

Jar tests are used to show the effectiveness of chemical treatment in a water treatment facility. They are also useful for evaluating new coagulants or polymers for use on a plant scale. This article presents jar test procedures for water treatment plant operators. The following factors related to the coagulation process and jar tests that operators need to be aware of are discussed: chemical selection, detention times, alkalinity, and polymers. Guidelines for conducting accurate jar tests are presented. Steps in performing jar tests are outlined, and the evaluation of jar test results is discussed. Variations and improvements to the standard jar test are described.