Industrial Wastewater Project Summary:

Wastewater type: High-salinity, high-organic-load non-ferrous industrial wastewater
Technology: Niobium substrate boron-doped diamond (BDD) anode-based electro-oxidation
Reported process context: Hazardous-waste salt recovery / resource recycling
Test duration: 6 hours
Primary targets: Total Organic Carbon (TOC) and Total Nitrogen (TN)
Streams tested:
1. Hazardous-waste salt dissolution brine
2. Evaporation-crystallization mother liquor

1. Treatment Challenge

High-salinity waste streams from non-ferrous industrial operations can contain both concentrated organic carbon and nitrogen. These streams are difficult because salinity can restrict biological treatment while the dissolved organic load can interfere with salt recovery, evaporation and reuse.

The supplied data evaluate niobium BDD anode-based electro-oxidation on two distinctly different high-salt matrices over six hours.

2. Stream 1: Hazardous-Waste Salt Dissolution Brine

Time       TOC (mg/L)                Cumulative TOC Removal              TN (mg/L)             Cumulative TN Removal
Influent  28,050                               —                                                       174                                   —
1 h            26,075                              7.04%                                                159                                  8.62%
2 h           23,775                              15.24%                                                146                                 16.09%
3 h           20,825                              25.76%                                               141                                 18.97%
4 h           17,700                               36.90%                                              129                                 25.86%
5 h           15,800                              43.67%                                               124                                 28.74%
6 h           13,200                              52.94%                                               119                                 31.61%

After six hours, TOC decreased by 14,850 mg/L and TN decreased by 55 mg/L.

3. STREAM 2: EVAPORATION-CRYSTALLIZATION MOTHER LIQUOR

Time       TOC (mg/L)             Cumulative TOC Removal         TN (mg/L)     Cumulative TN Removal
Influent   6,765                                      —                                          875                       —
1 h             4,538                                  32.92%                                   578                     33.94%
2 h             4,060                                 39.99%                                   508                    41.94%
3 h             2,755                                  59.28%                                   510                     41.71%
4 h             2,053                                 69.65%                                   488                     44.23%
5 h             1,590                                  76.50%                                   403                     53.94%
6 h             1,313                                   80.59%                                   345                    60.57%

After six hours, TOC decreased by 5,452 mg/L and TN decreased by 530 mg/L.

4. Performance Interpretation

Both high-salinity streams responded to electro oxidation, but their kinetics and final removal percentages were very different.

The hazardous-waste salt dissolution brine had an extremely high starting TOC of 28,050 mg/L. Electro oxidation trial module reduced this load by 52.94% over six hours, while TN removal reached 31.61%.

The evaporation-crystallization mother liquor started with lower TOC but much higher TN. It responded more rapidly and reached 80.59% TOC removal and 60.57% TN removal after six hours.

The contrast between the two streams shows that “high-salinity wastewater” is not a single treatability category. Organic composition, nitrogen species, salt chemistry and concentration can strongly affect electrochemical oxidation rates. The data support wastewater-specific treatability testing rather than assuming one universal residence time.

A small increase in TN from 508 to 510 mg/L occurred between hours 2 and 3 in the mother-liquor dataset. This is minor relative to the overall trend and may reflect analytical/sampling variation or transformation among nitrogen species; the worksheet does not provide enough information to determine the cause.

5. Industrial Relevance

For salt-recovery and resource-recycling systems, reducing TOC before evaporation/crystallization can help lower the organic burden carried into recovered salt or concentrated mother liquor.

Potential electro-oxidation roles include:
– Pre-treatment before salt crystallization or reuse.
– Destruction of dissolved organics in hazardous-waste salt recovery.
– TOC/TN polishing of concentrated mother liquor.
– Treatment of side streams where salinity limits biological processes.
– Integration with evaporation, crystallization and other zero-liquid-discharge operations.

6. Engineering Notes And Data Limitations

The source worksheet does not report electricity consumption, current/current density, electrode area, pH, conductivity, salt composition, chloride concentration, reactor volume, temperature or flow conditions. Consequently, this dataset demonstrates removal performance but does not by itself define full-scale energy cost or electrode sizing.

The reported percentages have been retained from the worksheet. No unreported process conditions have been inferred.

7. Key Takeaway

Electro-oxidation treated two challenging high-salinity non-ferrous wastewater streams. After six hours, TOC/TN removal reached 52.94%/31.61% in hazardous-waste salt dissolution brine and 80.59%/60.57% in evaporation-crystallization mother liquor, demonstrating strong but matrix-dependent performance.

Source: collected from on-site testing of the client’s facility, data evaluated and collected by Evoaeo’s engineering team.