Figure 1
(a) Examples of mixing zone for river discharges: (A) a traditional shoreline discharge, (B) a submerged offshore single-port discharge, (C) a regular perpendicular diffuser design and (D) a diffuser design for navigating rivers or rivers with other cross-sectional limitations. BMZ – the width of mixing zone, LMZ – the length of the mixing zone downstream. BMZ at distance LMZ must be greater than BMZ specified in the water legislation [4]. (b) Photo of a fragment of the discharge installation damaged by sediment (after disassembly).
Figure 2
A diagram of the flow of the KGHM mine water [13].
Figure 3
The discharge system during construction.
Figure 4
Cross section of the discharge installation, dimensions in mm [14].
Figure 5
The relationship between the flow of the Odra River and its natural salinity.
Figure 6
Three-dimensional model of the Odra riverbed, with the brine outflow zone marked.
Table 1
The results of the maximum concentration value and the component values of velocity vector ux.
| Distance | Case | (i) | (ii) | (iii) | Error (ii) - (i), % | Error (iii) - (ii), % |
|---|---|---|---|---|---|---|
| X = 250 m | Cs (kg m−3) | 0.991 | 0.999 | 0.997 | 0.80 | −0.14 |
| X = 250 m | ux (m s−1) | 0.999 | 1.000 | 1.000 | 0.12 | −0.13 |
| X = 500 m | Cs (kg m−3) | 2.022 | 2.140 | 2.173 | 5.52 | 1.52 |
| X = 500 m | ux (m s−1) | 1.442 | 1.448 | 1.437 | 0.43 | −0.71 |
Figure 7
Image of the brine concentration in the cross section at the end of the model: (a) grid 1 × 1 × 0.5 – 500,000 elements, (b) grid 0.67 × 0.67 × 0.31 – 1,912,500 elements and (c) grid 0.5 × 0.5 × 0.25 – 4,400,000 elements.
Table 2
Measured values of the brine concentration at selected depths in the Odra River upstream and downstream the discharge.
| Location | Salinity of the Odra River at selected depths | ||||
|---|---|---|---|---|---|
| kg m−3 | kg m−3 | kg m−3 | kg m−3 | ||
| m | m | m | m | ||
| 80 m upstream the discharge | 0.188 | 0.188 | 0.181 | 0.185 | |
| 2.2 | 1.5 | 0.6 | 0.0 | ||
| 420 m downstream the discharge | Left riverbank | 0.614 | 0.594 | 0.594 | 0.565 |
| 2.5 | 2.0 | 0.6 | 0.0 | ||
| Middle of the river's current | 0.549 | 0.566 | 0.565 | 0.565 | |
| 2.5 | 1.5 | 0.5 | 0.0 | ||
| Right riverbank | 0.266 | 0.246 | 0.263 | 0.257 | |
| 1.5 | 1.0 | 0.5 | 0.0 | ||
Table 3
Brine propagation simulation results (Cs) compared with the measurements of chloride content (Cm) at the end of the model section.
| Left riverbank | Middle of the river's current | Right riverbank | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| h | Cs | Cm | Δ | H | Cs | Cm | Δ | h | Cs | Cm | Δ |
| m | kg m−3 | kg m−3 | kg m−3 | m | kg m−3 | kg m−3 | kg m−3 | m | kg m−3 | kg m−3 | kg m−3 |
| 0.0 | 0.400 | 0.380 | 0.020 | 0.0 | 0.287 | 0.380 | −0.093 | 0.0 | 0.218 | 0.072 | 0.146 |
| 0.5 | 0.401 | 0.413 | −0.012 | 0.5 | 0.287 | 0.384 | −0.097 | 0.5 | 0.219 | 0.082 | 0.137 |
| 1.5 | 0.407 | 0.406 | 0.001 | 1.5 | 0.290 | 0.379 | −0.089 | 1.0 | 0.220 | 0.059 | 0.161 |
| 2.5 | 0.410 | 0.426 | −0.016 | 2.5 | 0.292 | 0.361 | −0.069 | 1.5 | 0.224 | 0.078 | 0.146 |
Table 4
Input data and results.
| No. | Qi | Ai | uxi | qd | uzd | Cd | Cavg | Cmax |
|---|---|---|---|---|---|---|---|---|
| m3 s−1 | m2 | m s−1 | m3 s−1 | m s−1 | kg m−3 | kg m−3 | kg m−3 | |
| 1 | 41 | 63.58 | 0.645 | 0.282 | 0.0007 | 40 | 0.2729 | 0.341 |
| 2 | 51 | 75.25 | 0.678 | 0.425 | 0.0010 | 40 | 0.3306 | 0.341 |
| 3 | 77.2 | 106.11 | 0.728 | 0.767 | 0.0018 | 40 | 0.3933 | 0.497 |
| 4 | 113 | 139.07 | 0.813 | 1.467 | 0.0035 | 40 | 0.5125 | 0.632 |
| 5 | 169 | 173.75 | 0.973 | 2.000 | 0.0047 | 40 | 0.4678 | 0.560 |
| 6 | 318 | 246.77 | 1.289 | 2.000 | 0.0047 | 40 | 0.2500 | 0.340 |
Figure 8
Spatial distribution of chloride for low flow 41 m3 s−1 at elevation (a) 68.45, (c) 69.08, (e) 69.38 m asl and for high flow 318 m3 s−1 at elevation (b) 68.45, (d) 69.08, (f) 72.13 m asl.
Figure 9
Distribution of chloride in the cross section at the end of the model for flow values: (a) Qi = 41 m3 s−1, (b) Qi = 51 m3 s−1, (c) Qi = 77.2 m3 s−1, (d) Qi = 113 m3 s−1, (e) Qi = 169 m3 s−1 and (f) Qi = 318 m3 s−1.
Figure 10
Distribution of the concentration of brine in the outlet cross section for (a) Qi = 41 m3 s−1 and (b) Qi=318 m3 s−1.