Division BAT 13 When further removal of organic substances or nitrogen is needed, BAT is to use an additional treatment step as described in Section 1.21.2.
United Kingdom
Table 3
BAT-associated emission levels for direct waste water discharges from the refining of mineral oil and gas and monitoring frequencies associated with BAT f1
| Not all parameters and sampling frequencies are applicable to effluent from gas refining sites. | |||
| Refers to a flow-proportional composite sample taken over a period of 24 hours or, provided that sufficient flow stability is demonstrated, a time-proportional sample. | |||
| Moving from the current method to EN 9377-2 may require an adaptation period. | |||
| Where on-site correlation is available, COD may be replaced by TOC. The correlation between COD and TOC should be elaborated on a case-by-case basis. TOC monitoring would be the preferred option because it does not rely on the use of very toxic compounds. | |||
| Where total-nitrogen is the sum of total Kjeldahl nitrogen (TKN), nitrates and nitrites. | |||
| When nitrification/denitrification is used, levels below 15 mg/l can be achieved. | |||
| Parameter | Unit | BAT-AEL(yearly average) | Monitoringf2 frequency and analytical method (standard) |
|---|---|---|---|
| Hydrocarbon oil index (HOI) | mg/l | 0,1-2,5 | Daily EN 9377- 2f3 |
| Total suspended solids (TSS) | mg/l | 5-25 | Daily |
| Chemical oxygen demand (COD)f4 | mg/l | 30-125 | Daily |
| BOD5 | mg/l | No BAT-AEL | Weekly |
| Total nitrogenf5, expressed as N | mg/l | 1-25f6 | Daily |
| Lead, expressed as Pb | mg/l | 0,005-0,030 | Quarterly |
| Cadmium, expressed as Cd | mg/l | 0,002-0,008 | Quarterly |
| Nickel, expressed as Ni | mg/l | 0,005-0,100 | Quarterly |
| Mercury, expressed as Hg | mg/l | 0,0001-0,001 | Quarterly |
| Vanadium | mg/l | No BAT-AEL | Quarterly |
| Phenol Index | mg/l | No BAT-AEL | Monthly EN 14402 |
| Benzene, toluene, ethyl benzene, xylene (BTEX) | mg/l | Benzene: 0,001-0,050 No BAT-AEL for T, E, X | Monthly |
Annotations
Footnotes
- f1
-
Not all parameters and sampling frequencies are applicable to effluent from gas refining sites.
- f2
-
Refers to a flow-proportional composite sample taken over a period of 24 hours or, provided that sufficient flow stability is demonstrated, a time-proportional sample.
- f3
-
Moving from the current method to EN 9377-2 may require an adaptation period.
- f4
-
Where on-site correlation is available, COD may be replaced by TOC. The correlation between COD and TOC should be elaborated on a case-by-case basis. TOC monitoring would be the preferred option because it does not rely on the use of very toxic compounds.
- f5
-
Where total-nitrogen is the sum of total Kjeldahl nitrogen (TKN), nitrates and nitrites.
- f6
-
When nitrification/denitrification is used, levels below 15 mg/l can be achieved.