RO/NFUFMBR

Chemicals

CASE STUDY

RO | UF | MBR |Wastewater Treatment
Wuxi, China

High-Surface Area Toray UF Modules Solve System Footprint Challenge
at Wuxi High-Tech Industrial Park
BACKGROUND
The Wuxi High-Tech Industrial Park began
enforcing discharge guidelines issued by China's
Ministr y of Environmental Protection that
require wastewater treatment plants to meet
the Surface Water III Class standard.
Th e s t a n d a rd wo u l d m a k e i t d i f f i c u l t fo r
conventional secondary treatment to meetthe criteria for discharge. One of the plants
in the industrial park, Wuxi Xingcheng Water
Reclamation Plant ( WRP), with a capacity of
170,000 cubic meters per day, could not meet
the water quality requirements and evaluatedimplementing new treatment technologies.
However, due to limited footprint and therequirement to reduce suspended solids,
the EPC contractor for Wuxi WRP, GreenTech
Environmental Co., Ltd (GreenTech), evaluatedultrafiltration (UF) membrane technology
the most effective treatment of the industrial
wastewater, as illustrated in Figure 2.

Figure 1: UF system at Wuxi installed with Toray HFUG-2020AN UF modules

Table 2 — Water Quality

Table 1 — Quick Facts
Capacity

34,000 m³/d UF outlet

No. of trains

4

No. of modules

520

Operating mode

as recommended by TorayTemperature

12–25 °C

CommissionedOctober 2019

unit: mg/L

Previous filtrate quality

Target filtrate quality

CODcr

20

18

BOD54

3.6

Suspended solids

121NH3-N

1

1

Total Nitrogen

55Total Phosphorus

0.2

0.1

Figure 2: industrial wastewater treatment design

Industrial effluent

Biological Aerated Filtration

Granular Activated Carbon

03-CN-MB2-XiwuI-202108Ultrafiltration

1 of 2Cloth Filter
DischargeOzone

High-Surface Area Toray UF Modules Solve System Footprint Challenge
at Wuxi High-Tech Industrial ParkC A S E S T U DY
RO | UF | MBR

PRODUCT ADVANTAGESTORAY UF hollow-fibers feature the following advantages(detailed comparison in Table 3):

degrees Celsius flux requirement and leave room for expansion under
the required operating conditions.

•S p u n u s i n g a p ro p r i e t a r y t h e r m a l l y - i n d u c e d p h a s eseparation (TIPS) spinning method that produces a uniform
and even distribution of pores with a nominal pore size of
0.01 µm for low fouling potential and high rejection;

The UF system also features TorayWise™, a software that provides
real-time visuals of the operation, which helps plants prepare formaintenance and other operational needs.

•Unique composite PVDF UF membrane with low foulingsurface layer on high flux and high strength support layer for
extended membrane lifetime with minimal fiber breakage
and fouling;•Outside-to-in flow of filtrate results in higher flux operationfor extended periods. This flow configuration effectively
removes suspended solids during air-scrubbing and makes it
ideal for treating high turbidity feeds.

Toray's UF membranes, valued for their membrane durability,
low-fouling, and high flux rates, continue to operate stably andefficiently, helping the Wuxi WRP meet stringent wastewater
discharge requirements.

HFU

HFUG

I.D.
0.9 mm

I.D.
0.7 mm

SELECTION PROCESS

O.D.
1.1 mmO.D.
1.4 mmGreenTech evaluated Toray's UF membranes for structural
integrity, fouling and flux rates, field data, and cost factors suchas membrane module lifetime, and selected Toray's new highsurface-area HFUG-2020AN UF membrane modules.
As illustrated in Figure 3, the thinner hollow-fibers of the HFUG2020AN allow for a 25% increase in membrane area per module
within the same dimensions as the previous model (HFU-2020N).
This feature enabled the end-user to work within existing footprint
parameters to exceed the target production rates of 45 lmh at 12

HFUG-2020AN
UF module
Figure 3: UF hollow-fiber diameter comparison

Table 3 — UF comparison
UF typeUnitMembrane modelPrevious model

New high-surface area model

HFU-2020N

HFUG-2020AN

Membrane material

PVDF (Polyvinylidene fluoride)

Nominal pore size

µm

Outer membrane surface area

m2

72

90

Innermm0.90.7

Outermm

1.41.1

Typical feedwater / filtrate flow

m3/h

2.6–8.0

4.5–12.3

Full of water

kg

11092

After draining

kg

6749

Diametermm

216

216

Lengthmm

2,160

2,160

Hollow-fiber
diameter

Weights

Dimensions

0.01

TORAY INDUSTRIES, INC.
Head Office: Nihonbashi Mitsui Tower 24th Floor, 1-1, Nihonbashi-Muromachi 2 chome, Chuo-ku,Tokyo, 103-8666, JAPANwww.water.toray+81 3 3245-4542

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All information presented herein is believed reliable and in accordance with accepted engineering practices. Toray makes nowarranties as to the completeness of this information. Users are responsible for evaluating individual product suitability forspecific applications. Toray assumes no liability whatsoever for any special, indirect or consequential damages arising from thesale, resale or misuse of its products. © 2021 Toray Industries, Inc. Subject to change without notice.
03-CN-MB2-XiwuI-202108

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