_-, Adhesives Research Ireland Ltd, Raheen Business Park, Limerick, Ireland Phone Fax

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1 /-I- _I I n s i g h t Adhesives Research ARcare Division _-, Adhesives Research Ireland Ltd, Raheen Business Park, Limerick, Ireland Phone Fax Licensing Unit Administration, Office of Climate Change, Licensing and Resoace Use, EPA PO Box 3000 Johnstown Castle Estate, Co. Wexford lenvf ronmerrtal Protectton Agency 15 AUG th August 2007 Ref PO Condition Dear Sir/Madam I am writing to you to request a change to Condition of our IPC Licence, Register Number PO This condition states that The concentration limits for emissions to atmosphere specified in this licence shall be achieved without introduction of dilution air and shall be based on gas volumes under standard conditions of in the case of thermal oxidiser gases Temperature 273K, Pressure Ea., dry gas, 18% oxygen. I request that the conditions are changed to Temperature 273K, Pressure Pa., dry gas, 20% oxygen. I am enclosing a report drafted by Durr Systems GmbH on various oxidiser technologies and why correction to 18% oxygen should not be required for thermal oxidiser systems. As stated in this report Due to the low fuel demand, the oxygen content in the flue gas which exits the RTO is very high: 19-20,5 % by volume Typical oxygen measurements since August 2006 have been in the range 19.1% to 20.5%. The last three oxygen measurements that have been recorded by EPA sampling staff have been 19.8%, 19.3% and 20.3%. Adhesives Research Ireland would continue to measure the oxygen content at both emission points A2-1 and A2-2. It is also my understanding that other Agency Licensed facilities that use Durr supplied Thermal Oxidisers correct to 20% reference oxygen. The condition should be the same for all facilities using the same technology. Registered In Ireland No _. - - I / An independent developer and manufacturer of pressure-sensitive adhesives, tapes, specialty films, coatings, and laminates -- --_--d (- L I i. - -\

2 ~.-L l ll ~ ' i a.i' IJ Ives Research Ireland Ltd, Raheen Business Park, Limerick, Ireland Fax At present a typical oxygen content measurement would be 20.4%. We then have to multiply our mg/m3 result by a factor of 5.8 to correct to 18% oxygen. I feel that this is a excessive and restrictive condition on our licence. There will be no increase in emissions as a result of the change and therefore there will be no environmental impact from the change I await your decision If you have any questions or require further clarification please contact me. Yours sincerely Ger Harte Environmental Health & Safety Officer Adhesives Research Ireland Ltd. L ~ Registered in Ireland No' , /--- 1 ' ~ 7 --._.~-.-I.- An independent developer and manufacturer of pressure-senr;itive adhesives, tapes, specialty films, coatings, and laminates. 1 i I

3 PRODUCT INFORMA TlON Thermal Oxidisers for Waste Liquids and Off Gases EcopureB-VA R Economic System Solutions for Production Facilities With VOC-Emissions and Heat Demand Durr Systems GmbH Environmental and Energy Systems Stuttgart Phone (071 1) Telefax (07 1 1)

4 EMISSION MEASUREMENTS IN FLUE GASSES AFTER THERMAL OXlDlSERS General Thermal oxidisers are in use for the cleaning of polluted air from industrial processes, e.g. coating plants as well as waste gasses and liquid residues, which are generated beside the main products in industrial production plants, e.g. chemical or pharmaceutical plants. In the combustion chamber of thermal oxidizers, waste VOC components are oxidized in the presence of oxygen (combustion air) at temperatures in a range of "C. Combustion products are non toxic components as CO2 and H20 in the case of pure hydrocarbons and toxic components like HX, X2, Son, SOS, NO, NO2 in case of the presence of hetero atoms like Halogens (X), Sulphur (S), Nitrogen (N) etc. in the VOC molecules. The following oxidation reaction equations are shown without respect to the stoichiometry of the reactions: Pure hydrocarbons: CnHmOp + Oxygen (Air) + Halogenated hydrocarbons: CnHmOpXy + Oxygen (Air) + Free halogens Xnare formed in the combustion chamber by following the Deacon equilibrium: HX H20 + X2 Sulphur components: CnHmOpSx + Oxygen (Air) + Nitrogen components: CnHmOpNx + Oxygen (Air) -.) CO2 + Hz0 COz + Hz0 + HX + X2 CnHmOpN02 + Oxygen (Air) + CO2 + H20 + NO2 Toxic compounds need to be removed before blowing the flue gas into the atmosphere. Therefore it is necessary, to provide acid or caustic scrubbers and/or De-NOx units downstream to the combustion chamber. CO2 + H20 + SO2 + sot Normally the hot flue gasses which exit the combustion are subject of heat recovery. The concept therefore is customer specific and oriented on the energetic demands of the production units and the corrosive behaviour. CO2 + H20 + N2 + NO + NO2

5 Oxvaen in the Purified Flue Gasses Due to their provenance, the compositions of waste gaseous streams varies in a wide spectrum. The content of oxygen can be in the whole range between 0 % by volume (inert off gasses from chemical production processes) and 21 % by volume in the polluted air of many industrial processes. As a consequence of the waste gas composition and the specific fuel demand for the heating to combustion temperature, the oxygen content of flue gasses which exits oxidisers varies also in a wide range. Polluted air with low content of VOC s is normally cleaned in regenerative thermal oxidisers (like Durr s Ecopure@RTO units). In this type of oxidisers the polluted air is preheated to temperatures which are C lower than the combustion temperature, normally 800 C. Due to the low fuel demand, the oxygen content in the flue gas which exits the RTO is very high: % by volume. Polluted air or off gasses with medium load of VOC s (up to 25 % of lower explosion limit LEL) are often preheated to temperatures of C in gas / gas heat exchangers prior to entering the combustion zone. Hot medium is flue gas which exits the combustion. The oxygen concentration in the flue gasses of this type of post combustion units (Durr s Ecopure-WAR) varies in the range o/o by volume. For off gasses with high VOC-content and / or reduced oxygen concentrations normally oxidisers with internally ceramic lined combustion chambers are used, like Durr s units. The oxygen content of the flue gasses which exit the combustion chamber varies in the range of 3-13 % by volume depending on the off gas concentration and the combustion temperature. Emission Measurements In order to minimise industrial pollutions, Environmental Authorities elaborated detailed regulations, which contain maximum emission concentrations for the most toxic components contained in the flue gasses after industrial and purification processes. The first and most detailed collection of environmental guidance and rules is the German so called TA-Luft ( Technische Anleitung zur Reinhaltung der Luft ). The guidance for emission limit values for waste components in industrial waste gasses and purified gases which are released into the environment, were introduced in Germany in a collection of environmental laws, the BimSchG = Bundes-lmmissionschutz Gesetzgebung.

6 These days, the legislation of the European Community regulates emission limit values for many industrial processes and purification processes. The units for emission concentration limit values are mg/ms (at standard conditions p, T) or ppm (parts per million). One of the intentions of the environmental legislation is, to minimise the absolute emission of emission sources in kg/hr. In order to not allow dilution of polluted gas streams with air, which leads to lower concentrations, but not reduces the absolute emission rate, an oxygen correction of measured emission values has to be made in many cases to a reference oxygen content. Probably the first oxygen reference value is 3 % by volume for industrial gas burners used in direct fired heaters and boilers. Oxygen Correction For the oxygen correction of measured emission concentrations, following equation is used: Ccorr= Cmeas~ (21 - %On.ref) / (21 - %02,meas) Ccom = corrected emission value (mg/ms) Cmeas = measured emission value (mg/ms) 02,ref= Reference value of the oxygen concentration in the purified gas (% by volume) O2,meas = Measured oxygen concentration in the purified gas (% by volume) If the reference value of oxygen is lower than the measured value, a corrected emission value results which is higher than the measured value. As reported above, the spectrum in the oxygen concentration of purified gasses after combustion units is % by volume. The main reason for high concentrations is effective preheating of process gasses to high temperatures, in order to minimise the fuel demand for the purification at sufficient high temperatures. Due to the low fuel consumption, such technologies - mostly gas burner fired - are environmental friendly. The absolute values of CO2 and pollutant emissions are low. In order to not disadvantage such technologies, the environmental legislation defined 0 2 reference values, which are oriented on a typical oxygen concentration of industrial or purification processes. For industrial burners used for firing of heaters and boilers, the reference value is 3 % by volume. This is an average value for the com bustion with 5-20 % air excess, typical for gas burners in direct fired heaters. Combustion units for solid and liquid wastes are all followed by a thermal oxidiser, which operates - independent of the composition of the wastes - at temperatures between

7 n,,,.."' 900 "C and 1100 "C. The oxygen reference concentration is 11 % by volume and corresponds the typical concentration in the purified gas of the process. As reported above, the oxygen concentrations in purified gasses after thermal oxidisers for polluted air and off gasses varies in a wide range. It is not possible, to define a narrow reference value. Therefore, the emission values for this kind of purification plants have not to be oxygen corrected, the measured value must only be corrected to standard conditions 0 "C and 1 bar (a). Precondition for this procedure is, that the combustion flue gasses which exit the stack, are not diluted with air added downstream to the combustion chamber.