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Morgan Robbins
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1 Attachment F.1 Neutralisation System Process Description The CPG process generates both acid and caustic waste water from the acid/base leaching processes. This waste water will be collected in dedicated acid and caustic waste collection tanks (each ca. 10m3 capacity). There is a similar sized rinse water tank provided to collect equipment washings. The neutralization system comprises a further 10 m3 vessel equipped with an agitation and pumped circulation system complete with ph monitoring. The system will operate to optimize the neutralization available from mixing the acid and caustic wastes to minimize the requirement to use fresh neutralizing reagents. Fresh neutralizing reagents (ca. 32 to 36 % HCL and ca.30 % Sodium Hydroxide) are added under ph control to the recirculation loop to meet the ph emission limit of 6.5 to 8.5. We expect the temperature of the neutralized stream to be close to ambient. We anticipate operating the system in a batch mode configuration with the discharge of a full tank of ca. 10 m 3 taking place over a period of ca. 1 hour. The total discharge flow we expect from this system is ca. 50 m 3 per day. The system will be supplied with hydrochloric acid and sodium hydroxide from their respective bulk storage systems located adjacent to the neutralization system in the same bund. The vents from the acid wash tank and the neutralization tank will be routed to the adjacent scrubber system. The vents from the caustic wash tank and the rinse tank will be open to atmosphere as we do not expect any emissions of environmental significance from these tanks. The neutralization of acid and caustic waste water in the above manner is defined as F2 in section of the EPA Draft BATNEEC Guidance Note for the Manufacture or Use of Coating Materials. The above process is defined as BAT in section of the EU BREF on the Surface Treatment of Metals and Plastics. August This section provides for using acid and base waste water to self neutralize and the subsequent batch neutralization and discharge arrangement as outlined above. Page 1 of 5

2 Process Description - Dust Collection Systems The CPG process generates glass dust at a number of locations in the process itself and in the final inspection and packaging areas. The dust will be captured at source to ensure occupational exposure limits are met in all working areas of the plant. All dust laden air will be directed to the dust collection system where the dust will be removed prior to discharge of the air to the atmosphere. The dust collector is a conventional dust collecting unit equipped with cyclones and outlet filters. The unit will be designed, installed and operated to ensure that the TA Luft standards of 20mg/m3 or 0.2 kg /hr. are met. We expect the actual values achieved to be significantly less than this value. Design calculations suggest that these values will be less than 1 mg/m3. The system will be fitted with the following monitoring facilities : Operational indicator to confirm that the unit is operating Differential Pressure Alarm on the filtration system Filter Cleaning System operating indicator The unit will be monitored during the initial weeks of operation to determine the optimum settings for the filter cleaning system, the optimum time to remove the accumulated dust collected by the unit and to determine the appropriate frequency for filter change out. The waste material collected will be classified and an appropriate route of disposal selected based on the classification. The above system will meet the BAT guidance as defined in Section of the EU BREF Best Available Techniques in the Glass Manufacturing Industry December 2001 This section cites a range of emission values from 5 to 30 mg/m 3 with the comment that values in the lower part of the range would generally be expected for filter systems. We are therefore confident that this system will meet the TA Luft standard as outlined above. Page 2 of 5

3 Carbon Adsorption System Process Description The OS process requires the use of small amounts of the halogenated solvent Dichloromethane. The amount of this solvent to be used is quite small (ca. 200 liters per annum). The solvent will be handled at ambient temperature. Based on the very small quantity of Dichloromethane to be handled we expect the annual vapour losses to be relatively small. The process using this solvent will be operated only for short periods of time during the year as this product is manufactured to order. The solvent will be initially condensed using a vent condenser on the process reactor. The off gases will then be treated in a carbon adsorption bed prior to discharge to atmosphere. While the adsorption capacity of activated carbon is relatively low at 2 % the vent condensing combined with the small scale of the process and the low volumes of material processed means that a modestly sized bed should still be capable of removing any small amount of residual solvent from the air stream prior to discharge. The unit will be designed to meet the requirements of TA luft for Class I substances of 20 mg/m 3 or 0.1 kg/hr. The condensed liquid will be segregated and treated as hazardous waste for offsite incineration. The spent carbon will be removed periodically and disposed of as hazardous waste. During the commissioning period, testing will be carried out on the vent point from this system to confirm the efficiency of the removal mechanism and to determine the appropriate interval for replacement of the adsorption material. Indirect Cooling is considered BAT as described in BREF Surface Treatment using Organic Solvents January 2007 in section Adsorption is considered BAT as described in BREF Surface Treatment using Organic Solvents January 2007 in section Page 3 of 5

4 Process Description - Acid Fume Scrubber System The CPG process uses ca. 32/36 % hydrochloric acid and ca. 30 % sodium hydroxide as part of the glass formation process. The use of hydrochloric acid at this strength has the potential to generate acid fumes arising from its storage and use. All acid storage tanks and process equipment with the potential to generate acid fumes will be connected to a fume scrubber system to ensure these fumes are removed from the air streams prior to discharge. The scrubber will be a standard acid fume scrubber using low strength (ca. 5 %) sodium hydroxide to neutralize the acid fumes. The solution of sodium hydroxide will be circulated through a packed bed through which the process air will be fed in a counter current direction. The scrubber will be fitted with the following monitoring equipment: Scrubber liquid pressure Scrubber sump liquid level Scrubber sump ph The scrubber liquid will be replaced at ca. weekly intervals to ensure that the scrubbing process remains effective at all times. The spent scrubber liquid will be sent to the neutralization system for treatment and onward disposal to the local authority sewer. The proposed emission limit value for this emission point is 30 mg/m 3 at a mass flow limit of 0.3 kg/hr to meet the TA Luft Vaporous or Gaseous Inorganic Substances Class III limit. The likely emission will be less than this value as the maximum fume load on the scrubber is likely to be the displacement volume of the small bulk storage tank (ca. 10 m3) when it is filled from near empty. The estimated emission in this case is Counter current scrubbing is Adsorption to Water and is therefore considered BAT as described in BREF Surface Treatment using Organic Solvents January 2007 in section Page 4 of 5

5 Filter Dryer Process Description The OS process requires the use of a filter dryer to remove Methanol from the product. The unit is a Charles Thomson Pilot Scale filter dryer. The dryer operates under vacuum to optimize the removal of the methanol. The methanol vapours are condensed in a low temperature (-80 Deg C) in line condenser. The freezing point of methanol is -96 Deg C. The low temperature cooling at -80 Deg C will ensure that the majority of the methanol will be recovered with only trace amounts remaining after the chilled condenser. Initial calculation suggest that the emission from this vent will be less than 1µg/m3 which is significantly less than the TA Luft Limit for Methanol of 20 mg/m3 or 0.1 kg/hr. This application of low temperature refrigeration is considered BAT as described in the BREF Surface Treatment using Organic Solvents in section The recovered methanol is treated as hazardous waste and disposed of in accordance with the requirements of the IPPC license Page 5 of 5

ecodry Figure 1 - Process Diagram ecodry B General Process Description

ecodry Figure 1 - Process Diagram ecodry B General Process Description ecodry The process principal of the ecodry system is centered around the concept of drying in a closed steam loop, with a process-integrated thermal oxidation. The separation of flue gas from the drying