Theoretical models for construction of re-use systems
Mass flow in the system
To understand more about what is happening in a re-use system, a theoretical approach can be taken. In re-use systems is it important to have control over the different water flows (Q), amount of substances added and removed from the system (M) and, based on this, the concentration of sub-stances at different stages in the system (C):
C = M/Q
Q =water flow (l/min)
M =mass flow of substances (mg/min) C =concentration of substances (mg/l).
Based on this, a total picture of the re-use system, including the fish tanks, the water treatment system and water transport system can be drawn up as shown in (Fig. 10.4). Here the following indices are used:
i = new water into the tank
o = out from the tank to outlet (= Qi +Qri)
ri= out from the tank and into the re-use circuit ro = out of the re-use circuit and into the tank (Qri)
f= amount of substances produced or consumed by the fish
r= amount of substances removed from the re-use system.