Chapter 3 Decision Support Model (IUWS-DSM) - Tubdok

Chapter 3 · Decision Support Model (IUWS-DSM) 53
Calculation: direct non-potable reuse. It needs to be proved whether the reclaimed water
amount is bigger than the real needed amount. Maximal only the real needed amount is
supplied.
( c ⋅Q
; Q )
Q drct.reu.
= Min used . wa. used . wa. demand . B / C
where: Qdrct.reu. – water amount of direct non-potable reuse, m 3 /d
cused.wa. – coefficient of used water reclamation, -
Qused.wa. – collected used water or greywater, m 3 /d
Qdemand.B/C – water demand with Quality B or C, m 3 /d
Stage Two. In this stage, the costs and energy consumption of WIS are evaluated
followed by the comparison betweendifferent system options.
Step 5. The sizes of water intake and treatment facilities, and conveying system are
determined based on the information obtained from Stage One. The determination methods
are given in § 3.4.1.
Step 6. and Step 7. The costs and energy consumption of water system are hereby
calculated. The corresponding evaluation methods are described and discussed in § 3.4.2
and § 3.4.3.
Step 8. Based on the costs and energy consumption, the system options are compared,
and then the optimal or appropriate options are advised to system planners and decision
makers.
This is the general planning procedure. Since different types of water entities have their
particular attributes, the individual planning procedure varies, whereby it is further developed
and discussed.
3.2.2 Planning of water entity of GROUP type
As discussed in § 2.2.1, the water usage of WUU and WUC is obtained based on
EUWUP, where two types of EUWUP can be used. If local data are not available at all, the
information of adjacent area or similar projects can be used as references.
The main water sources of WUU and WUC are the external source, i.e. from their
superior water entities. The possible local sources are roof-water utilisation and direct nonpotable
water reuse, which can be calculated by Eq. (2) and Eq. (4).
Concerning the water infrastructure, it is not considered in WUC, as WUC has mostly
indoor water facilities. Therefore, only Stage One in Figure 25 is executed for WUC. Whether
the water infrastructure of WUU is involved in IUWS is not fixed, as it can either belong to the
local municipality or be the private properties. If the water infrastructure of WUU is included,
Stage TWO in Figure 25 is performed. Having small dimensions, all treatment facilities in
WUU are considered only as package plants. The information of their cost and energy
consumption can be obtained from the manufacturers. The information of pipe systems can
be directly obtained from either the statistical data, or modified data from the similar WUU, or
actual design.
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