Total Suspended Solids (TSS) is a measurement of the total solids in a water or wastewater sample that are retained by filtration.
WHY IS IT IMPORTANT?
TSS is an important water quality parameter measure for wastewater treatment operations and environmental health. Wastewater contains large quantities of suspended organic and inorganic material that must be removed through screening, filtration or settling/flotation methods prior to environmental discharge. TSS will also have adverse affects on UV disinfection blocking/scattering UV light bound for pathogen disinfection or alternatively requiring higher intensity for proper disinfection, increasing energy costs. If TSS is not removed properly through treatment, high concentrations can lower the water quality in the receiving environment. The suspended solids absorb light, causing increased water temperature and decreased oxygen which creates an unfavorable environment for aquatic life. It is also advantageous to monitor TSS in conjunction with BOD and COD as part of the BOD/COD is in the TSS form.
TSS is measured in laboratory by filtering a known volume of sample through a pre-weighed glass fiber filter of ~ 0.45 µm pore size to capture solids, although pore sizes of the filters used may vary and can be as large as 2 µm. The filter is then dried at 103-105 °C and weighed. The total process takes approximately 2 hours in laboratory to obtain results. TSS is determined using the formula below:
TSS (mg/L) = (weight of filter with solids – weight of filter) / sample volume