Solids are referring to matter or dissolved in water or waste water. Solids may affect water and effluent quality adversely in a number of ways. Water with high dissolved solids generally is not potable, and may induce unfavorable physiological reactions in the consumer. For these reasons, a limit of 500mg dissolved solids per liter is desirable for drinking water. Highly mineralized water also is unsuitable for many industrial applications. Water high in suspended solids may not be suitable for bathing. Solids analysis is important in the control of biological and physical wastewater treatment processes.
ESTIMATION OF TOTAL SOLIDS (TS)
A well-mixed sample is evaporated in a weighed dish and dried to constant weigh in an oven at 105OC. The increase in weigh over that of the empty dish represents the total solids.
· Evaporating dishes (100 ml capacity)
· Weighing balance
· Measuring cylinders
· Heat clean dish to 103OC to 105OC for 1 hour. Store and cool dish in desiccators until needed. Weigh immediately before use.
· Shake the water sample very well add 100 ml of it in an evaporating Petriplate.
· Put evaporating dish in to oven at 103OC to 105 OC for overnight.
· Next day take out it from the oven and cool in tin desiccators dish would be having dried residues in it.
· Measure the weight of evaporating dish.
· Put the data of pre weight and post weight of the dish in the following equation and calculate the amount of total solids present in the sample
mg total solidD/L = (A-B) x100
mL of sample
where, A = post weight of dish (weight of dried residues + dish)
B = pre weight (weight of dish)