Projected Methane Emissions from Abandoned Coal Mines in the UK

Abstract:

<p>This document is a report for the project titled 'Emissions from Abandoned Coal Mines in the UK'.</p> <p>This work to project methane emissions from abandoned coal mines to 2050 has been carried out as an extension to DEFRA Project EPG 1/1/149 "Development of a Methodology for Estimating Methane Emissions from Abandoned Coal Mines in the UK" . The projected emissions are calculated by adding the emissions from mines abandoned before 2004 (as in the full report) and emissions from collieries to be closed after that date.</p> <p>The modelled closure of collieries has been matched to the losses to production to maintain consistency with Entec's work on the operating mines methane inventory. On average, a reduction of about 1 million tonnes (Mt) production is equivalent to the closure of one colliery. It has been assumed that deep coal mined production will fall by 5Mt in the next 5 years (2005 to 2010), with a final 5Mt production being lost between 2021 and 2025.</p> <p>The emission of methane from collieries after closure has been derived primarily using a hyperbolic function, which calculates emission over time as a proportion of emission during production. An alternative methane emission calculation method (FPPROG) has been examined and found to correspond in general form with the hyperbolic function. The emission during production has been calculated from colliery production specific emission values calculated for individual collieries, with an allowance for gas utilised during production. Where the emission calculated from the hyperbolic function falls below the emission based on 0.74% of reserve, the latter value is used to bring it into line with the emission calculations for the rest of the coalfields. In addition, emissions from collieries closed in the near future have had allowance made for mitigation of the gas being released beyond the first year following closure.</p> This report is divided into the following sections: <ol> <li>Introduction</li> <li>Methane Reserve and Emissions from Mines Abandoned Before 2004</li> <li>Methane Reserve Calculations for Mines Closed After 2004</li> <li>Methods of Calculation of Projected Emission from Newly Closed Mines</li> <li>Calculation of Methane Emissions from Mines Closed After 2004</li> <li>Projections of Total Methane Emissions from Abandoned Mines</li> <li>References</li> </ol>

Author(s):

Kershaw. S.