Dairy PW Series
February 18, 2020 - Nathan Olszak
Dairy PW Series
Ultrafiltration – Protein Concentration
The Dairy PW Series family of polyethersulfone ultrafiltration membrane elements are characterized by a 20,000 molecular weight cut-off. Dairy PW Elements are typically used for protein concentrate up to 20% either from milk and sweet whey (not suitable for acid whey).
These elements feature a Durasan* Cage patented outer wrap, a selection of feed spacers, and polysulfone parts.
The Dairy PW elements comply with:
- FDA Regulations relevant sections of 21CFR
- EU Framework 1935/2004/EC
Table 1: Element Specification
Membrane P-Series, Polyethersulfone
| Model | Spacer mil(mm) | Active area ft2 (m2) | Outer wrap | Part Number |
|---|---|---|---|---|
| DAIRY PW3838C30 | 30 (0.76) | 69 (6.4) | Cage | 1228024 |
| DAIRY PW3838C50 | 50 (1.27) | 55 (5.1) | Cage | 1229303 |
| DAIRY PW6338C30 | 30 (0.76) | 217 (20.2) | Cage | 1207392 |
| DAIRY PW6338C50 | 50 (1.27) | 168 (15.6) | Cage | 1207393 |
| DAIRY PW6338C65 | 65 (1.65) | 129 (12.0) | Cage | 1223985 |
| DAIRY PW8038C30 | 30 (0.76) | 345 (32.0) | Cage | 1230789 |
| DAIRY PW8038C50 | 50 (1.27) | 263 (24.4) | Cage | 1230680 |
Figure 1: Element Dimensions Diagram
Table 2: Dimensions and Weight
| Model | A | B | C | Boxed Weight lbs (kg) |
|---|---|---|---|---|
| DAIRY PW3838 | 38.0 (96.5) | 0.833 (2.12) | 3.79 (9.6) | 7 (3.2) |
| DAIRY PW5838 | 38.0 (96.5) | 1.138 (2.89) | 5.71 (14.5) | 18 (8.2) |
| DAIRY PW6338 | 38.0 (96.5) | 1.138 (2.89) | 6.34 (16.1) | 18 (8.2) |
| DAIRY PW8038 | 38.0 (96.5) | 1.125 (2.86) | 7.91 (20.1) | 29 (13.2) |
- These elements are bagged dry before shipping.
- Internal diameter unless specified OD (outside diameter).
- The element diameter (dimension C) is designed for optimum performance in GE pressure vessels. Other pressure vessel dimension and tolerance may result in excessive bypass and loss of capacity.
Table 3: Operating and CIP parameters
| Typical Operating Pressure | 80-135 psig (555 – 931 kPa) |
| Typical Operating Flux | 10-25GFD (15-40LMH) |
| Clean Water Flux (CWF)1 | 59GFD (100LMH) @ 30psi and 50°C |
| Maximum Temperature | Continuous operation: 122°F (50°C) Clean In Place (CIP): 122°F (50°C) |
| pH Range | Continuous operation: 2.0-10.0 Clean In Place (CIP): 2.0-11.5 |
| Maximum Pressure Drop | Over an element: 12 psig (83 kPa) Per housing: 50 psig (345 kPa) |
| Chlorine Tolerance | 5,000+ ppm-days |
1. Clean water flux (CWF) is the rate of water permeability through the membrane after cleaning (CIP) at reproducible temperature and pressure. It is important to monitor CWF after each cleaning cycle to determine if the system is being cleaned effectively. CWF can vary ± 25%.