Table 1.
Characteristics of membranes and operating parameters of the process
| Process | Membrane symbol | Membrane material | Limit molar mass, Da | Process pressure, MPa | Volume flow rate of deionized water Jw * , 105 m3/m2·s | Recovered permeate % |
|---|---|---|---|---|---|---|
| UF | MW | Polyacrylonitrile (PAN) | 200,000 -500,000 | 0.5 | 5.46 | 50 |
| V5 | Polyvinylidene difluoride (PVDF) | 200,000 | 0.2 | 2.06 | ||
| 0.5 | 1.24–1.46 | |||||
| NF | DK | Composite (epidermal layer - polyamide) | 150-300 | 3.0 | 3.03 | |
| HL | 3.03 |
Table 2.
Characteristics of post-process washings from swimming pool systems
| Parameter | Unit | System | |
|---|---|---|---|
| SP + RP (sports pool and recreational pool) | JB (jacuzzi bathtub) | ||
| Color | m-1 | 9.00 | 2.00 |
| Turbidity | NTU | 27.60 | 9.22 |
| pH | - | 7.37 | 7.65 |
| Conductivity (PVC) | µS/cm | 1,350 | 3,300 |
| m-1 | 20.90 | 6.80 | |
| Total chlorine | mgCl2/dm3 | 1.28 | 0.73 |
| Free chlorine | mgCl2/dm3 | 0.37 | 0.33 |
| Chlorine, combined | mgCl2/dm3 | 0.91 | 0.40 |
| Ammoniacal nitrogen | mgN-NH4/dm3 | 1.90 | 0.10 |
| Nitrate nitrogen | mgN-NO3/dm3 | 19.00 | 4.00 |
Figure 1.
Hydraulic performance of the MW and V5 ultrafiltration membranes (ΔP=0.5 MPa) during filtration of washings from SP and RP swimming pool systems
Figure 2.
Hydraulic performance of the V5 ultrafiltration membrane at ΔP = 0.2 and 0.5 MPa during filtration of washings from the JB system
Figure 3.
Hydraulic performance of nanofiltration membranes (DK and HL) at ΔP=3 MPa for washings from the SP and RP systems
Figure 4.
Separation properties of ultrafiltration membranes MW and V5 (ΔP=0.5 MPa) in relation to reduction of a) absorbance RUV254 b) turbidity Rturbidity of washings from the SP and RP systems
Figure 5.
Separation properties of the V5 membrane at different transmembrane pressure values (0.2 MPa and 0.5 MPa) defined by the values of the average retention coefficients a) absorbance RUV254 and b) turbidity Rturbidity of washings from the JB system
Figure 6.
Separation properties of nanofiltration membranes (DK and HL) defined by the retention average ratio for a) absorbance RUV254 b) turbidity Rturbidity of the washings from the SP and RP systems
Figure 7.
Changes in the value of inhibition of bioluminescence of samples of washings before and after a) ultrafiltration for the V5 and MW membranes (ΔP=0.5 MPa) and b) nanofiltration for the HL and DK membranes (ΔP=3 MPa)