Environmental Engineering FOURTH EDITION

96 ENVIRONMENTAL ENGINEERING

Filter

I

I Holes

6

Figure 5-7. The Gooch crucible, with filter, for determining suspended solids, and the
evaporating dish used for determining total solids.

EXAMPLE 5.3. Given the following data:

-Weight of a dish (such as shown in Fig. 5-7) = 48.6212 g,

-100mL of sample is placed in the dish and evaporated. New weight of dish and

--The dish is placed in a 550°C furnace, then cooled. New weight = 48.6300 g.

dry solids = 48.6432 g.

Find the total, volatile, and fixed solids.

(dish + dry solids) - (dish)

Total solids =

sample volume

48.6432 - 48.6212

100

= (220) 10-6 g/mL

= (220) 10-~ mg/d

= 220 mgL.

(dish + unburned solids) - (dish)

sample volume

Fixed solids =

48.6300 - 48.6212

100

= 88 mg/L

Total volatile solids = Total solids - Total fixed solids

= 220 - 88

= 132mgL