An additional study was carried out in parallel alongside ESPREME for determining heavy metals emissions in Europe. This feasibility study tried to list main heavy metal emissions sources (those with metals emissions higher than 1% of the total emissions in Europe), and identifying the most suitable damage -reducing techniques to decrease these emissions. The following processes were selected as main heavy metal sources:
- Power and heat generation from combusting coal, liquid fuels, solid biomass or natural gas.
- Iron and Steel industry: sintering, coke production, foundry processes, pig iron production, steel production in open hearth furnace, basic oxygen furnace and electric arc furnaces.
- Non-ferrous industry processes: production of primary and secondary lead, zinc and copper.
- Chlorine production.
- Cement production.
- Incinerating Waste and cremation processes.
This list constituted the basis for selecting adequate emission reduction measures. Both primary (reducing emissions at source) and secondary reduction measures (e.g. end-of-pipe measures) were considered.
Among primary measures, those related to fuel supply and combustion modification were linked to power and heat generation through combustion. However, in general terms, primary measures involved heavy metal minimization in raw materials and fuels, switch of technologies, modification of installations, surveillance procedure improvement and good housekeeping of the environment of HM releasing process.
Secondary measures included particulate control techniques (electrostatic precipitators, filters and cyclones), absorption methods (flue gas desulphuration) and bed biofilters related methods. This last group of techniques (bio filtrating) was found not suitable for the project selected heavy metals. NOx reduction techniques (through selective catalytic reduction), photochemical methods (only by UV or through UV-activated sorbents) and chemical conversion methods (calomel reaction, Odda process, ect) were identified specifically for reducing Hg emissions.
Each control method was assessed by its % efficiency (percentage of emission reduction in relation to unabated emission) and was classified depending on its implementation degree. Moreover, bibliographic data and expert estimated values were used for estimating techniques’ costs. All these suggested methods for reducing heavy metals emissions were collected in a database, together with information about investment and operation costs, unabated emissions of processes and implementation degree.
ESPREME project. « Synthesis Report on Potential and Costs of Abatement Options for Heavy Metals in Europe ».