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Reference Document on Best Available Techniques in Common Waste Water and Waste Gas Treatment/Management Systems in the Chemical Sector (CWW BREF). Aivi Sissa Tallinn – Estonia 27 – 28 March 2007. Introduction. It was finalised late 2001 Developed to apply to the chemical industry
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Reference Document on Best Available Techniques in Common Waste Water and Waste Gas Treatment/Management Systems in the Chemical Sector (CWW BREF) Aivi SissaTallinn – Estonia27 – 28 March 2007
Introduction • It was finalised late 2001 • Developed to apply to the chemical industry ...contains valuable information for other sectors • It is a horizontal BREF
Borderline between vertical and horizontal chemical BREFsWaste water example P R O D U C T I O N Chemical reaction Waste water VERTICAL CHEMICAL BREFs Work-up Product isolation Product Recovery C O N T R O L CWW BREF Waste water treatment Recipient
Chemical industry The chemical industry covers a wide range of enterprises: • One-process-few-products enterprises with one or just a few waste water/waste gas streams • Multi-production-mix enterprises with many complex waste water/waste gas streams
Vertical chemical BREFs • Chlor-alkali (CAK) • Large Volume Inorganic Chemicals – Ammonia, Acids and Fertilisers (LVIC-AAF) • Large Volume Inorganic Chemicals – Solid and Others (LVIC-S) • Large Volume Organic Chemicals (LVOC) • Polymers (POL) • Speciality Inorganic Chemicals (SIC) • Organic Fine Chemicals (OFC)
Scope • Environmental management techniques • Generally applicable process-integrated measures (i.e. applicable with an identical purpose in distinct production processes) • End-of-pipe treatment applied on chemical sites to WW, WG and waste water sludge
Structure of the document • CH1: General description • CH2: Waste water/waste gas management • CH3: Applied treatment technology • CH4: Best available techniques • CH5: Emerging techniques • CH6: Concluding remarks
BAT – horizontal approach • The options for emissions prevention/control are assessed independently of the particular production process(es) • BAT embrace the most effective and suitable measures for achieving a high general level of protection of the environment as a whole against emissions • BAT are determined more broadly and include more than just technology
Implementation of BAT • Implementation of BAT in existing installations: • BAT can be integrated when major alterations are planned • BAT can be implemented in a step-by-step construction programme over a period of time • Implementation of BAT in new plants is not normally a problem
Waste water/waste gas management General Environmental Management • proper and consistent execution of a recognised EMS • use of management tools
Management techniques ENVIRONMENTAL MANAGEMENT SYSTEM MANAGEMENT TOOLS Inventory management tools Safety and emergency tools Strategic management tools Operational management tools Pollution incident response Risk assessment Monitoring Site inventory Internal targets EMFA LCA Fire fighting Choice of treatment options Stream inventory Bench marking Choice of collection system WEA Reduction of water usage and discharge Implementation of control option WW/WG control systems WG emission qualification Quality control
Process-integrated measures • General need for prevention/reduction of the amount of WW and WG and/or contamination within a production line These are generally production- or process-specific and their applicability requires special assessment
BAT for process-integrated measures Waste water/waste gas collection • Ducting and segregating waste water streams to their appropriate treatment system • Routing waste gases to treatment systems. These are emission source enclosure, vents and pipes
Waste water – key issues • Emissions to water can arise from, e.g., chemical synthesis, WGT (wet scrubbers) and rain water from contaminated areas • The majority of process water (70 – 90%) has a low pollution load (e.g. cleaning water, vacuum, exhaust air clean-up, pumps) • The remaining (10 – 30%) contains up to 90% of the pollution load
WW techniques that fit into the scope WASTE WATER TECHNIQUES End-of-pipe treatment Process-integrated measures Central treatment Individual treatment Final treatment Pretreatment RECIPIENT
BAT for waste water treatment • Four different strategies: • central final treatment in a biological WWTP on site • central final treatment in a municipal WWTP • central final treatment of inorganic waste water in a chemical/mechanical WWTP • decentralised treatment(s) All four strategies are considered as BAT when properly applied to the actual waste water situation The approach to reaching specific BAT conclusions follows the pathway of pollutants
Waste water Uncontaminated (e.g. rainwater) Contaminated Waste water sewerage system RECOVERY TECHNIQUES NF / RO Adsorption Extraction/Distillation Evaporation Stripping/gas treatment Organic Inorganic Pollutants unsuitable for biological treatment Heavy metals Salts and/or acids ABATEMENT TECHNIQUES (non biodegradable) Oxidation Reduction Hydrolysis Air oxidation Incineration Salts and/or acids Free oil Hydrocarbons Biodegradable substances ABATEMENT TECHNIQUES (biodegradable) Biological treatment Refractory or toxic organic Receiving water
Waste gas – key issues • Only rarely can waste gas streams with different characteristics be treated simultaneously • Waste gas streams can roughly be divided into ducted and non-ducted (diffuse, fugitive) emissions • The flow rate to be treated is a major parameter in the selection of abatement options • Recovery techniques are generally used for valuable products
WASTE GAS TECHNIQUES Ducted emissions Fugitive and diffuse emissions Process-integrated measures End-of-pipe treatment Capture Individual treatment Group treatment Central treatment STACK WG techniques that fit into the scope
BAT for waste gas treatment low temperature sources high temperature sources The approach to reaching specific BAT conclusions follows the pathway of pollutants According to treatment, the sources for waste gases are distinguished as:
Decision pathway for WGT: basis for BAT conclusions Substance recovery Energy recovery Low temperature: production, handling and work-up gases High temperature: Combustion gases Recovery techniques Membrane separation Condensation Adsorption Wet scrubbers Separators Cyclones Electrostatic precipitators Fabric filters VOC Inorganic volatiles Dust Dust NOx SOx HCl, HF Abatement techniques Biofiltration Bioscrubbing Biotrickling Oxidation (thermal and catalytic) Flaring Separators Cyclones Electrostatic precipitators Filtration Sorption SNCR / SCR
BAT AELs for waste gas treatment Low-temperatures waste gases There are no BAT AELs for low-temperature waste gases in the CWW BREF. These are reported in the corresponding vertical BREFs However, the BAT chapter of the CWW BREF reports performance levels related to the application of techniques
BAT AELs for waste gas treatment High temperature waste gases
Emerging techniques • Techniques not yet applied on a commercial basis or outside pilot plant operation. These could be applicable in the future at large scale operation • Assessment needed during the review of the BREF
Concluding remarks • High level of consensus achieved • There is a lack of information on: • performance data in combination with operational data (e.g. cross-media and energy issues) • costs
Revision of the CWW BREF • Planned to start late 2007/early 2008 • Currently preparing a comparative analysis of the first series of chemical BREFs: • to set guidelines/recommendations which will help the Technical Working Group (TWG) with the preparation of the review of the CWW BREF as well as during the review process