TORAY MBR
Instruction Manual
06-G-MB2-NHPAF-220801
37 of 63
VII. OPERATION CONTROL
1. Standard Operating Conditions
Table VII-1 shows standard operating conditions for “NHPA Series".
To ensure stable operation, operating parameters such as MLSS, sludge viscosity, DO
(dissolved oxygen concentration), and pH should be kept in the range of recommended
standard operation conditions listed in Table VII-1 below. All wastewater should pass through
a 3mm (or less) screening device before introducing into the membrane tank. Large solids
may damage the membrane surfaces.
If anti-foaming agents are to be added to the membrane tank, use only alcohol based
anti-foaming products. Do not use silicone-based anti-foaming agent which may
cause choking of membrane pores.
* Recommended:
Kurita Water Industries “Kuriless 653”
Schill & Seilacher “Structol SB2032”
The operating conditions may deviate from these standard conditions, depending on
condition of the sludge, raw water quality, and/or other given operating conditions.
Table VII-1 Standard Operating Conditions for “NHPA Series”
Parameter
Unit
Operating condition
MLSS
mg/L
7,000 - 18,000
Sludge viscosity*
mPa
⋅
s
Not higher than 100 **
Not higher than 250 ***
DO
mg/L
1.0 or more
pH
-
6 - 8
Liquid temperature
deg C
15 - 40
Scouring air
flow rate
NHPA050-1F
NL/min/Module
(Cubic feet/min/
Module)
430 (15)
NHPA100-1F
870 (31)
NHPA150-1F, 2F
1,300 (46)
NHPA150-3F, 4F
1,300 (46)
* Measured by single cylinder rotary viscometer.
** B type viscometer, e.g. VT-03F by Rion Co., Ltd at 62.5 rpm.
*** C type viscometer, e.g. TVC-10 by Toki Sangyo Co., Ltd at 20 rpm.
