The NAEI estimates emissions from solvent use broken down into a high level of detail. Different methodologies are applied in order to estimate emissions but, in general, one of three approaches is followed:
It is worth noting that the emission factor approach, which is an accurate method for many pollutants and sources, is not always very useful for solvent use. This is partly because it is difficult to generate good emission factors due to the diverse nature of many solvent-using processes. For example, a single printworks may use dozens of different inks, each of which might have a different solvent content. Other printworks is the same sector will probably use different combinations of inks, thus applying an emission factor calculated from data on ink use at a single plant may introduce significant errors. The other reason why emission factors are not always accurate for solvent-using processes is that many of these processes have been increasingly employing abatement techniques to minimise emissions of VOC, and will continue to introduce more abatement in the coming years. Emission factors, even if accurate for one year, will soon lose their validity. As a result, estimates for many solvent-using processes are now made based on assessment of emissions from each process on a frequently recurring basis. Table A19 summarizes the approach followed for each source.
A19 Procedures for Estimation of NMVOC emissions from Solvent Use
|
Source |
Approach |
Comments |
|
Aerosols (carcare products) Aerosols (cosmetics and toiletries) Aerosols (household products) |
Industry data |
Estimates provided by the British Aerosol Manufacturers Association |
|
Agrochemicals use |
Industry data |
Estimates provided by the Crop Protection Association |
|
Coating manufacture (glue) Coating manufacture (ink) Coating manufacture (paint) |
Emission factor |
Emissions calculated as 2.5% of solvent input to coating manufacturing processes |
|
Decorative paint (retail decorative) Decorative paint (trade decorative) Industrial coatings (agricultural and construction equipment) Industrial coatings (aircraft) Industrial coatings (coil coating) Industrial coatings (commercial vehicles) Industrial coatings (drum coatings) Industrial coatings (high performance) Industrial coatings (marine) Industrial coatings (metal and plastic) Industrial coatings (vehicle refinishing) Industrial coatings (wood) Printing (heatset web offset) Printing (metal decorating) Printing (newspaper) Printing (other flexography) Printing (other offset) Printing (other printing) Printing (overprint varnishes) Printing (print chemicals) Printing (screen printing) |
Industry data / emission factors |
The British Coatings Federation has provided activity data, emission factors and emission estimates developed following an extensive consultation exercise with member companies |
|
Dry cleaning |
Emission factor |
Emissions are estimated by modeling changes in dry cleaning activity and technology relative to 1990, for which year an estimate of solvent use by the sector is available. |
|
Film coating |
Data from regulators |
Processes within the scope of Secretary of State’s Guidance Note PG 6/14 |
|
Industrial adhesives |
Industry data |
Solvent consumption estimates are obtained from the Solvent Industry Association |
|
Industrial coatings (automotive) |
Data from regulators |
Processes within the scope of Secretary of State’s Guidance Note PG 6/20 |
|
Industrial coatings (metal packaging) |
Industry data / regulator’s data |
Combination of surveys provided by the Metal Packaging Manufacturers Association and earlier data from regulators |
|
Leather coating |
Data from regulators |
Processes within the scope of Secretary of State’s Guidance Note PG 6/22 |
|
Leather degreasing |
Industry data |
A single estimate of solvent use has been provided by the British Leather Confederation |
|
non-aerosol products (automotive products) non-aerosol products (cosmetics and toiletries) non-aerosol products (domestic adhesives & sealants) non-aerosol products (household products) non-aerosol products (paint thinner/remover) |
Emission factors |
Emission factors were developed following an in-depth study of the sector in 1994. Emission factors are not expected to change significantly from year to year for this sector. |
|
Other rubber products |
Industry data |
A single estimate of solvent use has been provided by the British Rubber Manufacturers Association |
|
Other solvent use |
Industry data |
An estimate is calculated from estimates of solvent consumption provided by the Solvent Industry Association |
|
Paper coating |
Data from regulators |
Processes within the scope of Secretary of State’s Guidance Note PG 6/18 |
|
Printing (flexible packaging) |
Data from regulators |
Processes within the scope of Secretary of State’s Guidance Note PG 6/17 |
|
Printing (publication gravure) |
Data from regulators |
|
|
Seed oil extraction |
Data from regulators |
|
|
Surface cleaning (1,1,1-trichloroethane) Surface cleaning (dichloromethane) Surface cleaning (hydrocarbons) Surface cleaning (other) Surface cleaning (tetrachloroethylene) Surface cleaning (trichloroethylene) |
Industry data / emission factors |
Estimates of cleaning solvents have been obtained from a number of industrial sources, and emissions are calculated from these data by applying an emission factor of 1000 kg/tonne for hydrocarbons and ‘other’ solvents and 900 kg/tonne between 1970 and 1990, decreasing linearly to 800 kg/tonne by 1995 for chlorinated solvents |
|
Textile coating |
Data from regulators |
Processes within the scope of Secretary of State’s Guidance Note PG 6/8 |
|
Tyre manufacture |
Data from regulators |
Data could not be obtained for two plants and so these are assigned an emission equal to the mean emission of the other plants |
|
Wood impregnation |
Emission factor |
Emissions are extrapolated from a single, industry-derived estimate on the basis of the output of the UK wood products industry. |
In the case of estimates based on data from regulators, it should be noted that solvent-using processes were not regulated in the same way as those in the rest of the UK at the times that data were obtained, and thus no data are available for plants in Northern Ireland. However, with the exceptions of tyre manufacture, and probably flexible packaging printworks and textile coating processes, it is not thought that any processes of these types are in operation in the region.