| Various biological and non biological particles form | | | | solids and inorganic solids. Most of this particles are |
| wastewater suspended solids. They play a vital part | | | | microorganisms. To get an estimate of the amount |
| during aeration methods commonly used for the | | | | of solids, a sample is taken from the aeration tank, |
| treatment of sludge. But it is important to estimate | | | | filtered through a filter paper to obtain the |
| their quantity to determine the time required for such | | | | suspended particles that get left behind on the filter |
| treatment. In this article I discuss a formula | | | | paper. These particles are then allowed to dry |
| commonly used to achieve this: | | | | completely and the weight of the filter paper is |
| MLSS | | | | noted. The weight of the filter paper prior to being |
| A mixed liquor is stored in an aeration basin where | | | | used for filtration is subtracted to find out the gain in |
| the thick liquid is a mixture of activated sludge and | | | | weight. The calculation used for this purpose is as |
| wastewater that is either a fresh load or that which | | | | follows: |
| has been settled. This water has a high concentration | | | | Total Suspended Solids Wastewater (TSS)/L = (A-B) |
| of solid particles in it. The concentration of these | | | | * 1000 mg / Sample Volume (ML) where |
| particles is known as MLSS. The unit used to express | | | | A represents the combined weight of the dried |
| this when measuring the quantity of these | | | | substance and the tissue filter paper written in mg |
| substances is mg/l. To put this simply it is the total | | | | and B represents the weight of the filter paper alone |
| amount of these substances in the aeration tank | | | | written in mg. The number of hours required for the |
| used during the activated sludge treatment. These | | | | aeration treatment depends somewhat on the results |
| wastewater suspended solids are a mix of organic | | | | of this test. |