Environment Report 2013

ENVIRONMENT REPORT 2013

6.11 Disposal of Backloaded Cuttings Backloaded cuttings are usually treated with drilling derived oily slops at specialist treatment plants in the north east of Scotland. The process, thermal desorption, involves heating the feedstock to vaporise and separate the base oil and water from the solid fraction. Though treatment parameters vary between plants, the vapour oil and water are driven from a processor into a condenser. Oil and water are then allowed to separate under gravity. The recovered solids, with a total hydrocarbon content below one per cent (non- hazardous), are sent to landfill for final disposal. In 2012, the recovered solids accounted for 56 per cent (31,920 tonnes) of the initial amount of backloaded cuttings. The recovered oil enters the national waste oils market and is reused as fuel. The treated water is discharged to sewer. ‘Other’ waste routes, for example water being discharged to the sewer system, amounted to 14,099 tonnes (25 per cent of the overall total).

Figure 14: Backloaded Cuttings from the UKCS by Disposal Route

Landfill

Incineration

Reuse and Recycle

Other

Waste to Energy

60,000

50,000

40,000

30,000

Tonnes

20,000

10,000

0

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

Source: EEMS August 2013

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