**4.6 Effect of the distribution of airlift pipes on oxygen supply efficiency 4.6.1 Experimental conditions and methods**

Using highly oxygen-transfer-efficient airlift part with a pipe diameter of 4 cm and effective height of 1 cm, as shown in Fig. 21, we examine the effect of airlift part configuration by arranging 1, 2 and 3 pipes inside. To keep aeration flux constant, air flow rate normalized to each piece of airlift pipe is set at 6 L/min. The detailed experimental conditions are tabulated in Table 5.

Fig. 21. The configuration of airlift part

Side view of apparatus Top view of apparatus


Table 5. Experimental conditions relating to the configuration of the airlift part
