IMPEL GUIDELINES ON DIFFUSE VOC EMISSIONS · emission estimation methods · emission reduction measures · licensing and enforcement practice

ABSTRACT

IMPEL, the environmental inspectors network for the EU, developed guidelines on diffuse VOC (volatile organic Compounds) emissions. The objective of the guidelines is to improve the monitoring, licensing and inspection of industrial activities. The guideline report includes a review of the emission estimation methods and a review of the emission reduction methods. The report is based on an EU wide inventory, hands-on experience with emission measurements and a comparison with the US EPA-guidelines and practice in the USA.

The guidelines are focused on the VOC emissions of diffuse sources of large process installations, both fugitive emissions (leakage from equipment) and emissions from storage tanks and loading/unloading. The installations
& emissions are common in refineries and (petro-) chemical plants. Excluded are emissions resulting from the use of solvents which are regulated by the EC Directive 1999/13/EC.

Although the targeted activities are restricted to the process industry it should be clear that various of the presented measuring methods, reduction techniques and licensing&enforcement practice are also applicable to other activities such as (off-shore) gas&oil exploration/production and military activities. Some of the remote sensing methods are well suited for measuring the diffuse emissions of landfill sites (e.g. methane leakage) . The paper highlights the essential aspects of diffuse VOC emission estimation methods in relation to environmental licensing & enforcement.

NOTE ON IMPEL
The European Union Network for the Implementation and Enforcement of Environmental Law is an informal network of the environmental authorities of EU Member States. The network is commonly known as the IMPEL Network. The European Commission is also a member of IMPEL and shares the chairmanship of management meetings.

The expertise and experience of the participants within IMPEL make the network uniquely qualified to work on certain of the technical and regulatory aspects of EU environmental legislation. The Network’s objective is to create the necessary impetus in the European Community to make progress on ensuring a more effective application of environmental legislation. It promotes the exchange of information and experience and the development of greater consistency of approach in the implementation, application and enforcement of environmental legislation, with special emphasis on Community environmental legislation. It provides a framework for policy makers, environmental inspectors and enforcement officers to exchange ideas, and encourages the development of enforcement structures and best practices.

Information on the IMPEL Network is also available through its web site at http://europa.eu.int/comm/environment/impel.

1. INTRODUCTION

1.1 Background
Establishing an environmental policy for industrial sources usually commences with a regulation of the large point sources. Attention is then focused on piped emissions, e.g. exhaust gases directed via a stack and wastewater through a discharge pipe. In general these piped emissions are well regulated and have been reduced substantially, to such an extent that the other emissions have become more and more dominating. With respect to atmospheric emissions of volatile organic emissions (VOC) these ‘other emissions’ comprise mainly leakage from equipment (fugitive emissions) and evaporation losses of storage, loading and unloading. These emissions are called ‘diffuse’ emissions. Monitoring of diffuse emissions is more complex compared with monitoring of piped emission sources. Abatement and regulation of diffuse emissions is a relatively new issue in some member states of the European Union (EU). It is however not common practice in all EU member states, this contrary to the USA where it is common practice for about 10-20 years.

The main environmental effect of VOC in general is their role in the formation of smog and ozone in the presence of nitrogen oxides. VOC in the ambient air are precursors to the formation of ground level (tropospheric) ozone, the primary constituent of smog. Smog and ozone cause respiratory damage, damage to property and vegetation (agriculture and ecosystems). Individual components of VOC are known for other negative effects such as toxic effects on health and ozone layer depletion in the stratosphere. Reduction of VOC emissions is not only beneficiary to the environment but also can lead to better workplace conditions, can reduce risks of fire, can reduce nuisance (odours) and can save money.

IMPEL, the environmental inspectors network for the EU, developed guidelines for implementing diffuse emissions regulations, both for licensing of industrial plants and for enforcement. The Netherlands’ Inspectorate for the Environment was in charge of the development project and commissioned Tebodin to assist as consultant. IMPEL adopted the guidelines in December 2000.

1.2 Objective and scope
The objective of the guidelines is improving the monitoring, licensing and inspection of industrial activities. The guidelines are focused on the VOC emissions of diffuse sources of large process installations, both fugitive emissions (leakage from equipment) and emissions from storage tanks and loading/unloading. The installations & emissions are common in refineries and (petro-) chemical plants. Excluded are emissions resulting from the use of solvents which are regulated by the EC Directive 1999/13/EC.

Although the targeted activities are restricted to the process industry it should be clear that various of the presented measuring methods, reduction techniques and licensing&enforcement practice are also applicable to other activities such as (off-shore) gas&oil exploration/production and military activities. Some of the remote sensing methods are well suited for measuring the diffuse emissions of landfill sites (e.g. methane leakage).

The guidelines are based on an EU wide inventory, executed in close co-operation with the members of the IMPEL working group on diffuse VOC emissions. The findings are summarised in this document.

1.3 European policy
Permit requirements are subject of the IPPC Directive (96/61/EC). The application of Best Available Techniques (BAT) is a cornerstone of the Directive and diffuse emissions are a subject that needs to be addressed in the
environmental permit. It is the intention of the European IPPC Bureau in Sevilla to develop BAT reference documents for about 30 industrial sectors and a few general subjects. Of interest are the sectors ‘refineries’, ‘large volume organic chemicals’ and 'storage' and the subject ‘monitoring’. These sectors BAT reference documents are being prepared.

The Technical Working Group on monitoring will cover the monitoring of fugitive emissions. It is however not their intention to provide a BAT reference document as it is not intended to specify the best monitoring techniques but it is their intention to provide an exchange of views and practices [1] to enhance the licensing. Furthermore it should be noted that a significant VOC emission reduction in Europe is the objective of several protocols and policy plans.