. Post-oxidation 2 stage quench and scrubber system for HCI removal (Venturi quench, packed tower scrubber) For inspection purposes only.

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1 SCHWARZ PHARMA APPENDIX 1 BASIS OF DESIGN AND PROCESS DUTY The justification for the choice of abatement technique is discussed in a separate BAT report for the BPC and Nitration pants. However the foowing buet points summarise the overa system: BPC:. Sma dedicated scrubbers for specific reactors/processes. Combined inerted and air-diute header systems, with prescrubbers (acid/base) for remova of HCI/NHB generated by process.. Regenerative Fameess Therma Oxidizer. Post-oxidation 2 stage quench and scrubber system for HCI remova (Venturi quench, packed tower scrubber). Heat exchange for visibe pume reduction Note : there are options for either DCM recovery by adsorption/desorption or remova prior to the oxidation stage by scrubbing. These are expored in more detai in the BAT document. Nitration:. nerted header. Regenerative Fameess Therma Oxidizer. Post-oxidation quench. Heat exchange for visibe pume reduction BPC Pant Non-Chorinated Streams: Operating Maximum Minimum Fowrate Nm3/h Pressure mbarg atmospheric Temperature C IO , voc mg/m VOC Components Acetone IMS Methano Touene Ethy Acetate Contaminants water: (saturation at up to 30%) Dichoromethane: traces HCI: c Omg/m3 NH,: ~5 mg/m3 c 000 mg/m3 H2 Page46 EPA Export :15:32:08

2 SCHWARZ PHARMA MTBE Acetic Acid MEK IPA Hexanes Heptanes THF Butane sobutyene baance: air BPC Pant Chorinated Streams: Operating Maximum Minimum Fowrate Nm3/h Pressure mbarg atmospheric Temperature C o voc mg/m Note: maximum conditions not coincident. DCM oad wi range from 5 to 40 kg/h. VOC Components DCM Acetone IMS Ethy Acetate Touene Hexanes Heptanes Contaminant water: (saturation at 5-10%) HCI: c0 mg/m3 (ex scrubber) baance: air EPA Export :15:32:09

3 SCHWARZ PHARMA Nitration Pant Operating Maximum Minimum Fowrate Nm3/h Pressure mbarg -15 atmospheric -30 Temperature C voc mg/m VOC Components Touene MIBK IMS Acetic Acid Contaminant water: (saturated at C) baance: air EMISSION DATA FROM FLAMELESS REGENERATIVE OXIDATION OPTION BPC Pant Combined chorinated and Non-chorinated Fowrate Temperature voc DCM HCI co NO, Nm3/h C - Operating 5000-I 0000 >50 Comment No additiona combustion air required. This wi normay be higher depending on organic oad. Use 50 as worst-case dispersion temperature. Can be owered by improved scrubber design if required This ow eve can be guaranteed if the NH3 from the process is imited to ~5 mg/m3. Aso assumes no NO, in the process. Nitration Pant Fowrate Nm3/h Operating Comment 5000 No additiona combustion air required. Page 48 EPA Export :15:32:09

4 Temperature C Use 50 as worst-case dispersion temperature. voc co NO, mgc/nm mg/nm3 mg/nm3 <20 <50 <IO This ow eve can be guaranteed if the NH3 from the process is imited to 41 mg/m3. Aso assumes no NO, in the process. EPA Export :15:32:09

5 SC.H WARZ PHARMA APPENDIX 2 BAT ASSESSMENT FOR ABATEMENT OF RESIDUAL VOC EMISSIONS STAGE 1: DEFINITION OF BAT ASSESSMENT OBJECTIVE To appraise candidate options for the prevention and minimisation of residua VOC reeases from the pharmaceutica production faciities of the Schwarz Pharma site in Shannon. These residua VOC emissions are assumed to arise after the upgrade to primary vent condensers is carried out. The options must be capabe of meeting the requirements Sovents Emissions Directive. of the STAGE 2: GENERATION OF OPTIONS TO MEET OBJECTIVE The choice of technoogy for pharmaceutica is infuenced by the foowing factors: process emission contro. Batch processing and the intermittent nature of the reeases. Variation in fow and concentration throughout batch cyces. Usuay there is a compex mixture of sovents used in the various production stages (reactor, washing, phase separation, drying etc). These VOC mixtures may be further compicated by the presence of water vapour, particuate and other waste gas compounds Due to the muti-purpose nature of the site and the high degree of remova/destruction required, the technoogies not taken forward for detaied consideration are:. carbon adsorption,. membrane technoogies and. absorption. The principa disadvantage with using granuated carbon is that for mutipe sovent streams the adsorption capacity of the bed can be affected. One sovent wi adsorb at the expense of eaving another ess seective sovent to pass through. A further disadvantage is that a significant amount of wastewater is produced foowing regeneration of the bed with steam. There are aso safety concerns due to the highy reactive nature of the carbon that can produce high heats of combustion and the potentia for bed fires, particuary during periods of start-up and shutdown. Typica eves of VOC in exhaust gas for carbon adsorption pants are 20 to 80 mg/nm3 (depending on organic). In terms Page 50 EPA Export :15:32:09

6 SCHWARZ PWARMA of the carbon regeneration 4kg of steam (per kg of organic adsorbed) typicay eaves sufficient VOC on the carbon to provide measurabe eves of VOCs in the exhaust gas. Due to the asymptotic nature of the reationship between steam used and residua VOC in the carbon, achieving VOC eves beow the typica requires significanty more steam to the point that it is economicay unviabe. Moecuar sieves and simiar membrane systems have simiar advantages and disadvantages but water vapour and some sovent materias can aso poison the adsorption media. Absorption using seective sovents and poyethyene gyco can achieve a 98% reduction in reeases but again there is a resuting iquid waste stream of gyco and sovent that needs to be desorbed, resuting in an aqueous /sovent mixture for disposa or effuent treatment. The gyco is aso very expensive. Section discusses the basis of choice for techniques taken forward for detaied consideration. In summary, the technoogies recommended for consideration for the proposed process duties of the BPC and Nitration pants are therefore: Low temperature cooing/condensation with recovery of sovent and Regenerative therma oxidation with heat recovery The foowing features can be appied to both technoogies, which makes them suitabe potentia candidates for the Schwarz Pharma appication:. Both of these two options are capabe of achieving very ow fina emission concentrations so there is a degree of future proofing incuded in the technoogy choice.. Both technoogies are non-specific in their treatment. Cryogenic condensation requires contro of the exchanger temperature but it is capabe of recovering most VOCs. Page 51 EPA Export :15:32:10

7 SCHVVARZ PHARMA The eimination of the non-viabe techniques in the previous section eaves the foowing two options for further detaied consideration:. A recovery technique of cryogenic condensation foowed by sovent recovery n A destruction technique of regenerative therma oxidation The foowing features can be appied to both technoogies, which makes them suitabe candidate for the Schwarz appication: Both of these two options are capabe of achieving very ow fina emission concentrations so there is a degree of future proofing incuded in the technoogy choice. Both technoogies are non-specific in their treatment. Cryogenic condensation requires contro of the exchanger temperature but it is capabe of recovering most VOCs. The principa features of the two candidate technoogies in the main text (Section 3) of this report. Comparison of Lona-term reeases are discussed Both candidate options are capabe of and woud be designed to achieve the 20mgCINm3 emission standard for VOCs. There is no difference between the options in the effect of ong-term reeases. The therma oxidation route incudes a post scrubber for the acid gases. The water from the scrubber wi contain a sma amount of akai and approximatey 12 kg/hr of sat formed by the neutraisation of hydrogen choride by caustic soda. Sat has an inhibitory effect upon bioogica systems at high concentrations however the mass of sat discharged to downstream effuent treatment is sma in comparison with the tota site discharge and its effect is minima. Comparison of Short-term reeases Both candidate options are capabe of and woud be designed to achieve the 20mgC/Nm3 emission standard for VOCs. There is no difference between the options in the effect of short-term reeases. Page 52 EPA Export :15:32:10

8 P F-t A R M A Comparison of Goba Warminq Potentia The therma oxidation option resuts in a reease of approximatey:. 15,000 tonnes/year of carbon dioxide which is used as the basis for comparison of goba warming potentia (i.e. a GWP vaue of 1). the reease of oxides of nitrogen is ony O.OGkg/hr so this is insignificant in terms of goba warming potentia. Comparison of Photochemica Ozone Creation Potentia In this case, the most significant substances are sovents. For both options, the fina emission imit vaue wi be ~20 mgc/nm3 so there is no significant difference between the options. Generation of Waste For cryogenic condensation the recovered sovent mix is a potentiay usefu product. However, pharmaceutica process recipes are deveoped with virgin or high purity sovents. There are a number of potentia azeotropes in the Schwarz mixture of sovents as discussed previousy. This further compicates recovery into usefu products. In addition, the recovery process requires expensive distiation and storage pant. There is therefore imited scope for re-use of the recovered sovent and it thus becomes a waste stream for disposa off site. Off-site recovery may be possibe but in terms of the site, it can be considered as a waste stream. The therma oxidation option does not have any additiona waste streams. Other Considerations The potentia for pume visibiity needs to be addressed in a separate assessment. In the case of the therma oxidation route the potentia for pume visibiity is reduced by aowing for the addition of excess heat to the exit stream. There is no significant difference between the options in terms of odour generation Page 53 EPA Export :15:32:10

9 STAGE 4: SUMMARY OF ASSESSMENT The two candidate options of cryogenic condensation and regenerative oxidation have very simiar environmenta reeases in that they are both capabe of, and woud be designed for, achieving the requirements of the Sovent Emissions Directive (a VOC emission concentration of ~20 mgc/nm3). There is no difference between the Environmenta option for the ong and short-term reeases of VOCs. Quotient of either There are some minor differences between the options in terms of the secondary impacts such as: n n n n Goba warming potentia Ozone creation potentia Reeases to water Pume visibiity However, the main difference reates to the voume of sovent that woud be recovered by the cryogenic condensation process. For the Schwarz Pharma appication, this sovent is a compex mixture with potentia azeotropes. There is imited scope for sovent reuse in pharmaceutica processes and the potentia for contamination (oss of entire batch and risk to patient heath) outweighs potentia benefits. In addition to the above points, there is a novety factor associated with cryogenic condensation. Athough the theory is sound, there are very few cryogenic units operating on muti-sovent streams at this sort of scae. There is therefore an associated technica, environmenta and financia risk in this particuar appication. There is an apparent arge variation in quoted capita costs for such systems due to the ack of background information and historica instaations. The capita cost of the therma oxidation option is significanty ower than that of the cryogenic condensation unit. The fameess oxidiser is currenty deemed to be the Best Avaiabe Technique for the treatment of residua VOC emissions from the BPC pant. In summary this is because:. There is no difference in the fina reease concentration achievabe with either option. Both options wi achieve a very high degree of VOC remova in ine with the requirements of the Sovents Emissions Directive.. The recovery of a mixed stream of condensed sovents causes additiona practica probems for the site which cannot easiy be addressed (ocation of additiona storage, increased fugitive emissions) n Technica risk due to novety of cryogenic condensation at this scae of fowrate Page 54 EPA Export :15:32:10

10 SCHWARZ PHARMA n Technica risk due to novety of cryogenic condensation for this compex mixture of sovents _..:. EPA Export :15:32:10

11 SCHWARZ PHARMA APPENDIX 3 VOC ABATEMENT TECHNOLOGIES Appendix 3.1 Emission Contro Overview Abatement of VOC emissions to atmosphere can be divided into four main sections: 1. High Temperature (Therma) Oxidation 2. Cataytic Oxidation 3. Adsorption; 4. Absorption; 5. Condensation. Each of the generic technoogies are divided into separate sub-sections covering the various specific types of process equipment. Each method has specific chemica contaminant and VOC concentration ranges to which it is most suited and certain characteristics that can render it unsuitabe for use. The efficiency of a specific process can be significanty affected by the inet concentration of organic. The remainder of this section wi review each of the nine sub-sections. Appendix 3.2 Therma Oxidation Overview Therma Oxidation is a common method used for the destruction of gas-phase and iquid-phase organics. Reativey ow operating temperatures and short residence times are used for VOC destruction (700 to 800% and 0.5 to 1 second). These conditions shoud be compared with the more rigorous requirements for iquid disposa, i.e. 2 seconds residence and 1, OO C pus temperature; aied with secondary combustion chambers and rapid quenching for dioxin/furan contro. Whie these conditions may not be required for VOC contro they indicate a trend towards turbuent combustion, onger residence times, higher temperatures and the contro of dioxins/furans. Section of the main report discusses Regenerative therma Oxidation in some detai. In particuar, it focuses on then fameess configuration. Appendix 3.3 Cataytic Conversion Appendix Process Description Cataytic incineration is a ow temperature oxidation process that uses one of two types of catayst to convert organics into carbon dioxide and Page 56 EPA Export :15:32:11

12 SCHWARZ PI-IARMA water. The cataysts are based on either precious metas or transition metas, supported on a ceramic matrix. The matrix can be in the form of an extruded cyinder, or in a fabricated shape such as a honeycomb. VOC containing air enters a pre-heat chamber and is raised to the operating temperature of the catayst: 250 C for the transition meta catayst and approximatey 350 C for the precious meta catayst. The preheat is suppied by either hot gas entering from a sma burner or a preheat heat exchanger in a therma oi circuit. e The heated air then fows through the catayst bed, typicay 12 deep, and is oxidised. The air passes through a heat exchanger for heat recovery prior to being exhausted to a oca stack. The heat exchanger can be connected so that it provides the pre-heat for the incoming air. Typicay at 70% heat recovery and 20% LEL VOC concentration the system is sef sustaining. The method operates at ow temperatures and is fabricated from ow cost materias. Ony oxidation of the organics takes pace, and NO, production does not occur. Typica destruction efficiencies are in the region of 95% to over 99% for the common organic sovents. Voumetric fowrates for the units typicay vary from 2,000 m3/hr to 40,000 m3/hr. Appendix Operating Cost, Data and Process Status Externa Fue Operating cost Process Status Sma pre-heat burner (or heat exchanger) Catayst Cataytic converters to heat the unit to operating temperature repacement cost is are widey avaiabe and maintain that temperature. Shoud the main operating and we proven in insufficient VOC be present for the system to be sef supporting. cost. Catayst repacement periods can be eight to ten years depending on process conditions but two years is more typica. VOC destruction. Appendix Process Probems The main probems associated with cataytic converters are described beow: Particuates in the exhaust gases can ead to bockages in the catayst bed Breakdown products and trace components can poison the catayst sites Page 57 EPA Export :15:32:11

13 PWARMA High eves of haogenated organics can poison the bed Appendix 3.4 Overview of Adsorption Adsorption is the retention of substances from the gas phase on soid surfaces. One or more components from a gas are retained on soid adsorbent. The reverse process is caed desorption. Purey physica adsorption is reversibe, i.e. the moecues stored on the surface of the soid can be desorbed again unchanged. This corresponds exacty to the requirements of sovent recovery. The mosf important industria adsorbents incude activated carbon, siica ge and moecuar sieves. Due to its hydrophobic character, activated carbon is particuary suitabe and is commony used for the recovery of sovents. Furthermore, it is distinguished by a very arge surface area reative to mass and hence aso by a high retention capacity for the substances concerned. Activated aumina and siica ges tend to be primariy used for drying gases, particuary under pressure. Moecuar sieves are characterised by a smaer pore size than carbon and have a higher desorption temperature, 100 C to 140 OC for carbon, 200 C to 300 OC for moecuar sieves. Activated aumina, siica ge and moecuar sieves (essentiay dehydrated zeoites) can be used for sovent recovery but their reativey high price and ower efficiency tends to excude their use in the majority of appications for VOC contro. Additionay they a have a high affinity for water vapour and preferentiay adsorb water before any other poutants. Subsequenty any gas streams to be treated by these adsorbents must be fuy dehydrated. Their strong affinity for water aso excudes the direct use of steam as the heat source for desorbing the organics. This resuts in additiona capita cost for gas heaters or vacuum units for the desorption step. Their high desorption temperatures aso tend to precude the use of steam as a gas heating medium and forces the use of costy heat transfer systems. The equiibrium in the sovent/air/activated carbon system is determined by the characteristics of the adsorption isotherms. It is true to say that with increasing concentration of an adsorptive in the gas phase, the oading of the adsorbent at a certain temperature aso increases. At the same concentration, the equiibrium oading decreases with increasing temperature. At constant temperature, the maximum obtainabe equiibrium oadings depend on the vapour pressure and the moecuar weight of the substance to be adsorbed. The adsorption rate must aso be controed Page 58 EPA Export :15:32:11

14 SCWWARZ PHARMA for certain organic compounds, i.e. ketones and for highy concentrated streams of benzene, where the energy reease during adsorption can raise the bed temperature to its ignition point. Fires in eary acetone recovery units were caused by this heat reease. In practice, the equiibrium oading is reduced to the so-caed working oading of the carbon. This ranges from 5-20% of the theoretica maximum weight. The oading is affected by the factors tabuated beow. Factors Affectinq AdsorDtion Description Moisture Water vapour is preferentiay adsorbed by carbon. Residua Sovent Loading (Hee) Fouing Therma Shock Whie carbon exhibits hydrophobic characteristics to iquid water, water vapour is often adsorbed in preference to organics. This oads the carbon and reduces the overa organic oading. The residua hee on the bed reduces the remova efficiency. Fine particuates and poisons, such as suphur compounds can enter the bed and become attached to the carbon. This reduces its adsorption capacity, and subsequenty shortens its effective ife. Therma cycing of the bed causes therma cracking of the carbon peets, producing dust which binds the carbon. a Appendix Process Description Depending upon the voume of gas to be treated two options are avaiabe, both operating on the same principe; Singe use and reusabe canisters. in-situ units with adsorbent regeneration and sovent recaim Appendix Singe use canisters Singe use canisters tend to dominate the ow voume gas ceaning market. Once a canister has adsorbed its fu compement of VOC it is removed from site. The adsorbent is either sent to and-fi or Page 59 EPA Export :15:32:11

15 SCWWARZ PHARMA regenerated. Canister based systems can achieve ower VOC outet concentrations than in-situ units as fresh adsorbenf contains no residua organics, or other contaminants. The potentia probems of poisoning, water contamination and particuate bockage can be experienced. Different canisters are avaiabe depending on the duty they are required to perform. For reativey ow fow rates with high VOC concentrations deep bed units are avaiabe, with canister sizes ranging from about 0.5m diameter by 0.75m high to about 1.5m diameter by 2m high and fow rates from about 200m3/hr to 6000m3/hr. Typica appications for these woud be on vents from tanks during fiing and drum fiing operations etc.. For high fow rates with ow VOC concentrations, typicay buiding extraction systems, arger area units are avaiabe. The size of these is typicay about 2.5m by 2.5m by 2.5m and can hande fow rates of around to 30000m3/hr. For higher fowrates modues can be inked together. Reusabe canisters can be instaed, these are steam ceaned to remove the organic waste and paced back into the process. The manufacturers of the carbon canisters estimate that some 3 tonnes of carbon per day wi be required. This is fet, by the manufacturers to be an impractica option and a sma in-situ adsorption process pant woud be required. Appendix In-situ units Fixed beds are used amost excusivey by adsorption process pant manufacturers and it is this type of unit that wi be described in more detai. Before continuing it is worth mentioning that the trend in the eary 1960 s towards fuidised bed systems has now ceased. The drawbacks associated with this type of operation have now become known. Typica probems incuded shortened carbon ife due to partice attrition, high running costs, difficuties in optimising contro of fuidising veocities and sighty ower remova efficiencies. In most cases, the production pants upstream of the adsorber operate continuousy. Consequenty, parae operation of two or more fixed beds is commonpace. One bed is oaded with the adsorptive (the VOC) whie the other, or others, are being regenerated. Rotating beds are aso avaiabe, which have a singe cyindrica bed which rotates continuousy through three chambers, namey adsorption, regeneration and drying/cooing. The rotating bed gives perhaps the most continuous mode of operation. Page 60 EPA Export :15:32:11

16 PHARMA Fixed-bed processes are further sub-divided by the type of desorption procedure: the steam regeneration process inert gas regeneration vacuum regeneration The seection of the idea regeneration process emerges from the pant conditions, the egisative requirements and the physica properties of the sovents. \ For sovents which are insoube or sparingy soube in water desorption by steam has proved extremey successfu and the use of carbon as the adsorber medium has amost become the industry standard. This is due to the fact that steam is the most widey used industria heat carrier and carbon a durabe, economic adsorbant. For the continuous operation of the unit, the regeneration time of an absorber unit must be ess than the tota oading time of the other vesses. The operation of a fixed bed adsorber foows a specific sequence that is described beow: - adsorption of the sovent vapours from the gas stream onto the carbon; desorption of the sovents with steam; drying of the carbon with hot air; cooing of the carbon. The sovent-bearing gas is passed through the on-ine adsorber and a purified waste gas eaves the unit. Once the carbon bed is saturated it is taken out of the process air stream and the next adsorber is put on-ine. The switch-over is carried out automaticay either by a continuous gas monitor which detects breakthrough or a timer. Desorption is more commony carried out with dry superheated steam which passes counter-currenty through the bed. The steam is condensed in the adsorber and taken up by the activated carbon. The steam suppies the energy and acts as the transport medium for the sovents that are desorbed. The sovent/steam mixture eaving the adsorber is condensed and passed to a phase separator vesse. Due to the soubiity of some sovents in water steam distiation may be required to separate the sovent from the water. In some cases the partia soubiity of some organics wi require steam stripping of the aqueous phase prior to discharge of the aqueous phase. Page 61 EPA Export :15:32:11

17 PHARMA The duration of the steaming step depends on a residua oading (hee) which is economicay achievabe. After desorption it is necessary to dry and coo the hot and moist bed. Drying is carried out with hot air that is foowed by cooing with ambient air. Appendix Operating Cost, Data and Process Status Operating conditions Operating costs Process Status 4kg of steam typicay eaves sufficient The main cost of This process is VOC on the carbon to provide measurabe operation is the widey avaiabe and eves of VOCs in the exhaust gas. steam required for we known. Typica eve of VOC in exhaust gas - 20 to desorption. 80 mg/m3 (depending on organic). 4kg steam per kg of Due to the asymptotic nature of the organic recovered. reationship between steam used and The typica ife of residua VOC in the carbon. Achieving VOC the carbon bed is eves beow the typica requires five to eight years. significanty more steam to the point that it is economicay unviabe. Appendix Process Probems The main probems associated with carbon adsorption are isted beow: The presence of fine particuate carbon in the exhaust stream may give rise to emission probems A arg e amount of steam may have to be used to ensure ow VOC eves in the exhaust stream during the desorption cyce There is a significant fire risk associated with ketones, adehydes and high concentrations of benzene It is possibe that the carbon may be contaminated by particuates, entrained iquids, high boiing point organics and suphur compounds Lower moecuar weight organics tend to be dispaced by the higher moecuar weight organics in mixed organic systems There is a risk of contaminating water during steam stripping Poymerisation may occur on the adsorbent Appendix 3.5 Overview of Absorption Systems Page 62 EPA Export :15:32:11

18 SC H WARZ PHARMA Absorption is the physica transfer of a soute (the organic) from one phase (air) into soution in another iquid phase (water/oi). It differs from adsorption as moecues of the soute are dissoved into the second phase and may often be chemicay changed. The poutants are absorbed to the point at which the vapour pressure of the poutant in the iquid produces a concentration of poutant just above the iquid surface that matches the concentration of poutant in the gas phase. This is known as the equiibrium mixture and in practice the concentration in the iquid phase is aways sighty ower than this. The main method for achieving this physica transfer is the gas/iquid contactor. With the soute transferring from the gas phase to the iquid, the contactor is described as a scrubber. For transfer from the iquid phase to the gas phase, desorption, the contactor is referred to as a stripper. Contactors are defined by mechanica type and scrubbing media, athough the medium and duty of the contactor effectivey fix the mechanica design. Subsequenty the contactors are grouped by scrubbing media and ony important mechanica design detais mentioned. Appendix Aqueous Scrubbers These use water to remove the poutants from the air stream. They tend to be imited to the remova of dust and water soube compounds. Appendix 3.52 Chemka Scrubbers These operate in the same manner as a water scrubber, but as the poutants enter the iquid phase they are chemicay converted into another compound. This prevents the poutant from exerting its true vapour pressure and aows more poutant to be absorbed into each unit voume of soution. This chemica conversion and the sight soubiity of a organics in water, aows reativey insoube compounds to be absorbed at eves far beyond their norma eve. For organics, the chemica systems are normay aimed at converting the organic into water soube acohos, or to directy oxidise it to carbon dioxide and water. Typica chemica systems for oxidation are hydrogen peroxide soutions (pus a soube catayst), hypochorite soutions, or a mixture of ozone (generated insitu) and UV ight (shining into scrubber sump). The main disadvantage of this type of system is that they are not suited to a arge throughput of organic. The chemica destruction of the organics takes a significant period of time. This eads to arge voume sumps to provide sufficient residence time and arge voumes of media Page 63 EPA Export :15:32:11

19 SC-HWARZ PHARMA to hod the organic in soution. The end resut is that the systems are more suited to diute 500mg/m3 or ess organic concentrations or odour contro probems. Appendix Bioogica Scrubbers These are a derivative of a chemica scrubbing system. The primary difference is that the chemica scrubbing medium is repaced by a bioogica system which feeds on the dissoved organics. The bioogica systems can be retained on open matrices (arge pore pastic sponges), or may be freey suspended in the scrubbing medium. Additiona feeds of sats, nutrients and ph contro chemicas woud be required. An exampe of a typica fixed matrix bioogica scrubber is a Peat Bed Scrubber (see figure 6). The process air is drawn into the top of a cosed unit and then down through a bank of mist sprays. This coos and humidifies the air to conditions that the biomass wi find acceptabe. If the inet air is too hot additiona cooing may be required. The gas passes through the wet peat (often synthetic) where the gas to water transfer of the organic takes pace. Due to the ow efficiency of the transfer, the gas fowrate through the bed is ow and the beds are very arge in comparison with a typica chemica scrubber. The bioogica species in the bed use the organics as a food source. The cean air exits the bottom of the bed and is exhausted ocay. The water fowing down the bed fas into a sump and is re-circuated back to the top of the bed. Nutrients are added to the re-circuated water and excess scrubbing medium is bed off. The main disadvantage of this type of system is that they are not suited to a arge throughput of food. The organics are assimiated into the biomass ceuar structure and the process, being natura, takes a significant period of time. This eads to arge voume sumps to provide sufficient residence time and arge voumes of media to hod the organic in soution. The end resut is that the bioogica systems are more suited to diute 500mg/m3 or ess organic concentrations or odour contro probems. Appendix Process Status Water scrubbers used to remove water soube organics ony are widey avaiabe in many designs. However, units specificay designed for the remova of non-soube VOCs are rare. Ony one UV/Ozone unit is known to exist in the UK and it is at a piot pant stage. Chemica and bioogica scrubbers for ow eve VOCs exist but their effectiveness and operabiity at high VOC eves are reativey unknown. Appendix Process Probems Page 64 EPA Export :15:32:12

20 PHARMA. Not effective for high eve non water soube organics. Low mass transfer rates for no water soube materia require arge packed beds. Certain organics such as phenos and haogenated compounds adversey affect bioogica systems. Aqueous phase destruction of organics requires significant amounts of energy and/or additiona chemicas. Organics that are water soube tend to produce arge voumes of contaminated waste water. Appendix Gyco and Oi Scrubbers Appendix Process Description Changing the iquid scrubbing medium from water to an organic is a very effective method of VOC contro. Remova efficiencies in the region of 99.7%+ are not uncommon. Oi scrubbers are sti subject to equiibrium constraints but the soubiity s of organics are higher. This higher soubiity aows a higher concentration in the iquid phase and hence a ower voume of oi is required. After absorption the oi is usuay passed directy to a steam stripper, where ive steam is used to desorb the organic from the oi. The steam organic mix is then condensed and the water/organic mixture gravity separated. The efficiency of the stripping operation, the voatiity of the oi, the soubiity of the organic in water a effect the design and operation of oi scrubbers. If the stripping efficiency is ow, the off-gas concentration of VOC wi be high. High voatiity ois, such as the commony used kerosene fractions, wi repace the origina VOC contamination with the organics contained in the oi. Gyco scrubbers operate in a simiar manner to oi scrubbers, but by using a ow voatiity gyco the contamination of the air eaving the scrubber is reduced to acceptabe eves. Typicay concentrations of 1 to 2 mg/m3 of gycos in the stripped air stream are obtained. If the VOC is partiay soube in water the condensate wi require treatment prior to discharge. In the cases where the organic is totay Page 65 EPA Export :15:32:12

21 SCWWARZ PHARMA soube in water, the organic wi require distiation to separate organic carried over from the steam stripping coumn. One aternative to this stripping operation is to absorb the organic in a ow voatiity oi and then send the oi to a boier. This is ony effective for faciities with arge oi fired boiers and sma VOC streams. Appendix Process Status Avaiabe as a custom designed pant with process guarantees. Appendix Process Probems There are severa potentia probems associated with this technoogy which are described beow: any soid particuates wi tend to bock the packing in the absorber coumn; the exhaust gas from the coumn may not be within ega imits, if high voatiity ois are used; * contamination of the sovents with the stripping organic wi reduce the vaue of the sovent recovered; secondary water treatment woud be required to remove water soube sovents and the sma proportion of partiay soube organics. 0 gyco systems use an akaine stabiiser and acid ingress into the scrubber must be prevented. Appendix Emusion Scrubber Appendix Process Description Emusion scrubbing overcomes the probems encountered in aqueous and oi media scrubbing by the use of an oi dispersed in water. The organic is absorbed from the gas phase into the water phase in the same manner as in aqueous scrubbing. The organic is then absorbed into the oi dispersed in the water. This aows the water to absorb more organic and even the sighty water soube organics are absorbed. The oi/water organic distribution mechanism differs from the water/gas equiibrium in that the oi can hod higher concentrations of organic than those present in the aqueous phase. This aows a voume of emusion to hod far more organic than a water or oi based system. Page 66 EPA Export :15:32:12

22 SCHWARZ PHARMA The emusion aso prevents recontamination as the oi has no free gas/oi surface. of the air stream by the oi The oi is separated from the emusion and stripped of the organic. The efficiency of the stripping can be owered to prevent contamination of the organic by the oi. The oi can then be re-emusified and returned to the scrubber without any efficiency decrease as the eve of organic in the oi is not the controing factor. The absorber iustrated operates in the foowing manner. VOC aden air is drawn through the primary fiter to remove any particuate. It is mixed with the emusion in a swir chamber where the gas/iquid transfer occurs. The emusion is then disentrained in an impingement fiter and dropet coection zone. The air passes through a fina fiter to remove any dropets prior to entering the fan from which the air is ejected to atmosphere. Quoted efficiencies of 95 to 99.5% are given and typica duties incude VOC contro from paint spraying. The units come in 5 sizes - 3,000; 4,000; 6,000; 8,000; and 10,000 m3/hr throughput, and require a distiation unit if the vegetabe oi used is to be separated from the organic for re-use. Appendix Process Status Ony one manufacturer of emusion scrubbers has been identified. Nine units have been constructed, four are in manufacture. The ongest operating ife of instaed pant has been 18 months as of February Visua inspection of the equipment showed significant short fas in the engineered quaity and indications from the manufacturer are that the process requires individua bending of oi mixes for each appication. Appendix Process Probems Short oi ife; due to its high biodegradabiity the oi becomes rancid; Recaim of the oi requires a secondary unit; Oi bends are required for differing VOC types; Dust and particuate require remova prior to entering the unit to prevent the emusion becoming contaminated with soids. Appendix 3.6 Overview of Condensation Ambient condensation is the most commony used technique for removing high concentration VOC streams. The process is carried out Page 67 EPA Export :15:32:12

23 by removing the heat of condensation to coo the organics to beow their dew point. Cryogenic systems, which use more energy, have the advantage that they can hande much more diute streams. There are various configurations avaiabe for each of the systems, each of which wi be discussed in more detai in the foowing sections. Appendix Ambient Indirect Contact e Appendix I Process Description Ambient Indirect Contact is the most commony used method of organic recovery. VOC aden gas, typicay we above the upper fammabe imit, often with steam as the primary constituent, and occasionay an inert gas, is passed over a bank of heat exchangers operating at between -2X to 30 C. The organics, and water, condense out and are coected. The exhaust gas is then vented. Appendix Process Probems The vapour pressure of most sovents at ambient conditions ensures that their exit concentrations are we above reguatory guidance discharge concentrations. If cod brine is used ice formation on the heat exchanger tubes can prevent the system operating at temperatures near to zero. Additionay a significant proportion, up to 90%+, of the energy removed during cooing of the gas stream is used to remove the atent and sensibe heat content of the water vapour. Appendix Ambient Direct Contact Appendix Process Description The cheapest option avaiabe for the remova of VOC aden air is to use a spray condenser which injects cooing water directy into the vapour stream. The organics and water condense and are coected. The exhaust gas is then vented to atmosphere. Appendix Process Limitation As discussed in the previous section the main probem with this type of system is that the exhaust gas is sti we above the concentration.guidance imit for VOCs. Page 66 EPA Export :15:32:12

24 SC H WARZ PHARMA As the gas is cooed by direct iquid contact it wi be necessary to further treat the iquid stream. If the sovent is insoube in water then this wi be achieved by gravity separation. However, if the sovent is soube then this contaminated stream wi need to be treated. If it is economic to recover the stream then a fractionation system wi be needed. Appendix Cryogenic Indirect Contact Appendix Process Description A typica cryogenic indirect unit is described beow. Aternative types of this design are avaiabe but a are based on the same basic technique and have simiar drawbacks. The VOC aden gas enters the first heat exchanger where an air bast cooer is used to remove the buk of the heat from the gas stream. The gas then enters a second heat exchanger that is cooed to approximatey -20%. It then enters a cryogenic heat exchanger where it is cooed to approximatey -40%. As the gas coos, the VOC saturates the gas and condenses onto the heat exchange surface. The gas then fows back into the second heat exchanger and coos the incoming gas prior to being recyced or vented. Liquid nitrogen is used to coo the cryogenic heat exchanger and the gas evaporated from this is fed into the inert gas stream. The iquids that condense in the heat exchangers are coected and pumped out to storage. Appendix Process Status Cryogenic indirect systems are typicay used if water vapour is not present in the VOC aden gas and the gas is to be recyced back to the process or further treated. Typicay, the source of the cryogenic gas feed is an inert gas suppy system. If water is present cycing the heat exchangers to above 4 C so that ice can be meted from the heat exchange surfaces is possibe. The thawing cyce requires mutipe exchangers to be used in parae and as the ice mets it tends to drop into the base of the exchanger. This can bock the drain ines and tends to increase the period required to cear the exchanger of sovent aden ice/water. Heating the she of the exchanger prevents this but adds significanty to the unit cost of the exchanger. Additionay the heat exchange surfaces have to be significanty enarged to aow for the decrease in heat transfer caused by the ayers of ice that form. Appendix Process Probems Page 69 EPA Export :15:32:12

25 PHARMA This system is primariy used in printing and coating where the drying ovens, for organ& ony, are inerted and gas and sovent recycing are economicay practica. Any water ingress into this system woud bock it and particuate woud fou the heat exchange surfaces. Water aden gas streams can be treated but at increased capita cost and significant operationa increase. The off-gas concentration from these units wi aso be significanty above the VOC contro imits. Appendix Cryogenic Direct Contact Appendix Process Description There are three main types of direct contact cryogenic units: iquid gas/cooant spray systems; ceaned meta surface; iquid bed. Liquid spray systems use a quench tower approach to VOC remova by spraying the cryogenic medium into the gas stream. They achieve rapid remova of organics, but require the cryogenic iquid to be pumped. Ice formation within the units aso occurs and thawing cyces are often required. Scraping or abrading the heat transfer surface to remove ice buid-up is a common method of removing the requirement for thawing cyces. Designs simiar to scraped wa condenser designs are commony used for this appication and aowances are made for the remova of ice and soids. Throughputs are ow for this type of unit due to the restricted heat transfer area. An aternative method of surface ceaning is to pace chied meta objects (i.e. bars) at cryogenic temperatures into a rotating barre through which the gas passes. As ice forms, it is removed by the abrasion between surfaces and aowed to drop out of the barre. The meta objects are periodicay chied by gas at cryogenic temperatures. This design requires significant mechanica detai in the equipment seas and chiing systems. Another more nove approach empoys a coumn packed with stee spheres which are circuated by removing them from the bottom of the coumn and returning them to the top via a bucket eevator. The spheres are cryogenicay cooed at the top of the coumn by either direct or indirect contact with iquid nitrogen. The VOC aden gas stream is introduced at the base of the coumn where most of the vapour Page 70 EPA Export :15:32:12

26 S%;HWARZ PHARMA condenses, the remainder desubimates out towards the coder top of the coumn. As the spheres convey to the warmer condensation zone of the system the ice mets and drips down, together with the accumuated condensate, through the perforated base. After the spheres eave the base of the coumn they are dried before being returned to the top. The fina system is the direct contact fuid bed system, and a description of a commerciay avaiabe unit foows; VOC aden gas is initiay cooed to a pre-set temperature. This cooing is done as an economy measure and may be omitted. The vapour stream then passes into the bottom of the chier where it fows up through iquid organic and is cooed typicay to -40%. The system then vents via the economizer heat exchanger. In the chier, the organics are condensed and separated, any water is converted to ice and ow meting point organics soidify. The chied organics eave via the overfow and are coected in a water/organic separator. Soids are fushed out of the bottom of the chier periodicay into the same separator (or an aternate unit if the sovent is to be kept water free). In the separators the sovent is returned to store and the water sent for fina treatment. The sovent in the chier is kept at -40% by a refrigeration unit and therefore does not require iquid gases for its operation. Appendix Process Appication This system overcomes the probems of ice and iquid gas use for processes with sma gas fows (ess that 1,000 m3/hr). Appendix Process Probems Water aden gas streams can be treated but at increased capita cost and significant operationa cost increase. Theoreticay the off-gas concentration from these units wi meet tight emission imits as remova efficiencies can be optimised by owering the outet temperature. Page 71 EPA Export :15:32:12

27 SCHWARZ PWARMA APPENDIX 4 P&IDS for VENT HEADER and ABATEMENT SYSTEMS BPC Pant E A-i E A E A Proposed Specia Scrubber Systems HSI & HS2 (Haar) Vent Headers SS & SS2 (Stainess) Vent Headers Nitration Pant E A Scrubber System of Nitration Pant (Under Revision),. (. i.g : 7 c 6 Page 72 EPA Export :15:32:12

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