Page 102 - Membranes for Industrial Wastewater Recovery and Re-Use

82 Membranes for Industrial Wastewater Recovery and Re-use

7500

5
a 5000
a
s
.h
2
s
'O 2500
0
Nonfired Water tube
0
0 40 80 120
Boiler outlet pressure, bar
Figure 3.3 Influence of boiler outlet pressure and type of boiler on recommended limits of conductivity in
boiler feedwater

150

7! I2O
ij 90
Y
6 60
3
7 30

0
0 5 10 15 20 25 30 35
Boiler pressure, MPa
-+Alkalinity *Silica + Iron -i- Manganese- Copper
Figure 3.4 Influence of boiler outlet pressure on recommended limits of alkalinity, silica, iron, manganese,
andcopper in boilerfeedwater

freshwater sources, such as surface water or groundwater, is dependent on the
local geohydrology, but would normally be similar to reclaimed water. As
shown, there are differences in the content of nutrients, organics, and salts
among the water sources. Seawater has higher levels of dissolved minerals than
estuarine water.
The suitability of a water source for use in recirculating water systems as
compared to once-through non-contact cooling is related to water quality and
water availability. High levels of dissolved minerals and/or can demand
additional treatment to prevent scale formation. For example, cooling systems
that rely on estuarine or seawater tend to be non-recirculating, unless it is
economical to provide on-site treatment for control of dissolved solids.