|
| Biological Cleaning Trial |
Unlike traditional cleaning chemicals Biological degreasers clean and also digest unwanted oil emulsions.
Oily water effluent captured within a separator can be further bioremediated by use of our Patented Bio Tubes, which digest up to 6 kg of oil per week for 6 − 8 months!
This strategy cleaning was recently tested at a busy 5 island Petrol Station in Holland. The operator had oil discharges averaging 500ppm and wanted to see these discharges reduced to the European Standard 858 − Class 1 − 5mg/Ltr and Class 2 − 100mg/Ltr.
This report shows how, over a period of 5 − 7 months, this objective was achieved.
The Petrol Station retailer engaged an Independent company to observe the trial and to analyse, on a two monthly basis, the results obtained.
The operator set the following objectives:
The operator ceased using in month One his traditional alkaline clean chemicals.
These were replace with:
| Forecourt Bio | − | An enzyme based cleaner used at a dilution of 1:20 to clean pumps, islands and areas adjacent to the diesel pumps. |
| OT8 | − | A Biological Oil Stain Remover used neat to remove oil stains across the forecourt. |
| Bio Tubes | − | A biological product that floats within the separator absorbing and digesting free oil. (One Bio Tube was placed in the second chamber and two Bio Tubes were placed in the third chamber). |
| Nov 1996 Month 1 |
Jan 1997 Month 3 |
Mar 1997 Month 5 |
May 1997 Month 7 |
|
| 1. Water sample pH | 4.9 | 2.6 | 6.6 | 6.7 |
| 2. Oxygen Demand | ||||
| BOD mg/Ltr. | 290 | 7950 | 225 | 165 |
| COD mg/Ltr. | 477 | 250 | 662 | 258 |
| BOD/COD | 0.61 | 31.8 | 0.34 | 0.64 |
| 3. Mineral Oil Fraction mg/Ltr. | ||||
| C10 to C12 | 38.00 | 390.00 | 3.90 | 0.85 |
| C12 to C14 | 99.00 | 570.00 | 5.80 | 0.84 |
| C14 to C20 | 250.00 | 1500.00 | 36.00 | 8.60 |
| C20 to C26 | 110.00 | 710.00 | 34.00 | 6.80 |
| C26 to C34 | 17.00 | 110.00 | 2.90 | 1.80 |
| C34 to C40 | 0.02 | 12.00 | 2.20 | 0.16 |
| 4. Total Oil C10 to C40 | 514.02 | 3292.00 | 84.80 | 19.05 |
| 5. Target mg/Ltr. < | 20.00 | 20.00 | 20.00 | 20.00 |
Starting at a pH of 4.9, within 3 months the pH had reduced to 2.6.
After investigation it was discovered that a night shift operator in Month 3 had emptied battery acid into the separator producing the reading of 2.6!
From Month 4 to Month 7 the pH remained steady at 6.6.
In Month 3 the Forecourt Manager was so delighted with the OT8 Biological Oil Stain Remover that he used it to remove oil stains from the entire forecourt (5000 sq m).
This resulted in a large excess of surface oil being discharged to the separator in Month 3. By the end of Month 7 Oxygen demand was unchanged at 0.64.
Under normal circumstances the separator should have been emptied and cleaned. However, it was decided for the excess oil to remain within the separator to test fully the effect of biological cleaning.
The results showed a dramatic reduction from Month 3 to Month 7 across the Carbon Chain (see above table).
In Month 1 effluent oil discharges were 514 mg/Ltr.
In Month 3, following the total site clean up using Biological Stain Remover OT8, oil discharges were 3292 mg/Ltr!
This was reduced to 19 mg/Ltr. by the combination of the Bio Tubes within the separator and the continued use of Forecourt Bio.
Forecourt Bio used at a 1:20 dilution proved very effective in cleaning pumps and islands. Operators noted that when applied to surface diesel spills the area contaminated was restored to its original surface condition.
They also commented that the more frequently they used Forecourt Bio to clean diesel spills the less they needed to use − confirming that biological cleaning continues to remain effective long after application.
OT8, our Biological Oil Stain Remover was very effective in removing oil stains across the forecourt.
Our recommendation to the operator was that OT8 should be used regularly for individual oil stains and every six months for general forecourt cleaning (after which the separator should be emptied and cleaned).
The Bio Tubes placed within the separator worked very effectively. In month 3 the separator has excessive oil content and high oil discharge (see answer to Q1 for an explanation of this high oil content).
By Month 7 these discharges had been reduced from 3292 to 19 mg/Ltr., a reduction of 95%.
Our recommendation to the operator was that 3 Bio Tubes should be replaced six monthly after each complete emptying and cleaning of the separator.
| Oil Technics Ltd: Linton Business Park - Gourdon - Aberdeenshire - Scotland - UK - DD10 0NH | ||
| Telephone: +44 (0) 1561 361515 | Fax: +44 (0) 1561 361011 | Email: info@oiltechnics.co.uk |