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Yearly average emission and consumption levels associated with the use of BAT for non integrated uncoated fine paper mills, non integrated coated fine paper mills and non Table 6.31 integrated tissue mills. 1 2 Parameter Units Uncoated fine paper Coated fine paper BOD 5 kg/t of paper 0,15-0,25 0,15-0,25 COD kg/t of paper 0,5-2 0,5-1,5 TSS kg/t of paper 0,2-0,4 0,2-0,4 AOX kg/t of paper <0.005 <0.005 Total P kg/t of paper 0.003-0.01 0.003-0.01 5 Total N kg/t of paper 0.05-0.2 0.05-0.2 6 Wastewater Amount m3/t paper 10-15 10-15 notes: 1) The fibre furnish might be e.g. 100% bleached kraft pulp and fillers and sizes might amount to 15-30%. For mass sized paper the upper ranges for COD and BOD have to be considered 2) The fibre furnish might be e.g. 100% bleached kraft pulp and fillers coating colour might amount to 20-40%. Upgrading of paper colours consist of both surface sizing and application of coating 3) Fibre furnish 100% purchased chemical pulp. For tissue manufactured of a fibre mix of recycled and virgin fibre, see also chapter 5.4.2 4) The higher AOX value can be caused by wet strength agents that contain chlorinated organic substances 5) For coloured grades the nitrogen releases can be higher when N-containing azo dyestuffs are used 6) For mills which are producing coloured or strong coloured grades fresh water consumption can normally bit be bought below 17 m3/t 7) A change of basis weight and speed of the paper machine have a significant effect on the specific water consumption (SWC). Lower basis weights (down to 12 g/m2) and lower speeds corresponds to higher SWC. BOD In well designed treatment plants BOD5 is removed almost completely (95% + removal) from paper mill waste water when the carbon- phosphorus-nitrogen ratio and oxygen supply is maintained sufficient and well controlled. In case of disturbance or if some of the running parameters are moving away from the target level the BOD5 concentration in effluents will start to increase. This calls for adjustment of the running parameters and/or analysis of the biomass. BOD5 levels will usually be below 25 mg BOD5 / l and can reach values down to 5 mg/l (almost completely removal). However, BOD5 levels around 5 mg/l are hardly to measure accurately and reproducible. Depending on the water flow this correspond to 0,15 kg BOD5 /t (at 10mg/l and 15m3 flow/t) and 25 kg BOD5 / t respectively (at 25 mg/l and 10m3 flow). COD Depending on the paper grade manufactured, the applied techniques for prevention and control of emissions and the water flow per tonne of product, the wastewater from paper mills after treatment contains between 50-150 mg COD / l. TSS Under normal operation conditions, the water from the secondary clarifier is fairly clear. The content of suspended solids is in the range of below 20 to 30 mg/l. This corresponds to discharges of 0.2 - 0.4 kg TSS/t. The values depend on the surface load of the secondary clarifier and the characteristics of the biomass. With bio filtration also lower concentrations are normally achievable. AOX Nowadays, discharges of chlorinated organics are very low as the purchased pulp used in non-integrated paper mills is normally either ECF or TCF bleached pulp. Activated sludge treatment result in a further AOX reduction between 30 and 50%. However, this reduction is partly achieved by stripping of these compounds during wastewater treatment. Depending on the purchased pulp and chemical additives used paper mills discharge chlorinated organic compounds below 0,005 kg/t. N AND P Mineral nutrients are usually added to the biological treatment plant to keep the balance C : P : N which is of crucial importance for the growth of active biomass. To find and keep a balance between biodegradable carbon, nitrogen- and phosphorus-compounds a certain fine-tuning of the added nutrient feed is required. Usually, phosphorus is added as phosphorus acid and nitrogen in form of urea. When the system is well optimised nutrients discharge well below 1 mg tot-P/l and 5 mg total N/l are achievable. The corresponding loads are 0.003-0.001 kg P/t and 0.05-0.2 kg N/t respectively. ls associated with the use of BAT for non rated coated fine paper mills and non 3 Tissue 0,15-0,4 0,4-1,5 0,2-0,4 <0.01 4 0,003-0,015 0,05-0,25 10-25 7 ht amount to 15-30%. For mass sized paper might amount to 20-40%. Upgrading of paper mix of recycled and virgin fibre, see also sumption can normally bit be bought val) from paper mill waste water when the carbon- olled. In case of disturbance or if some of the running ts will start to increase. This calls for adjustment of the w 25 mg BOD5 / l and can reach values down to 5 mg/l asure accurately and reproducible. Depending on the BOD5 / t respectively (at 25 mg/l and 10m3 flow). and control of emissions and the water flow per tonne of mg COD / l. ations are normally achievable. sed in non-integrated paper mills is normally either ECF between 30 and 50%. However, this reduction is partly on the purchased pulp and chemical additives used Table 6.32 Emissions levels associated with the use of BAT for different fuels Released substances Coal Heavy fuel oil Gas Oil Gas 100-200 1 100-200 1 mg S/MJ fuel input (50-100) 5 (50-100) 5 25-50 <5 80-110 2 80-110 2 mg Nox/MJ fuel input (50-80 SNCR) 3 (50-80 SNCR) 3 45-60 2 30-60 2 mg dust/Nm3 10-30 4 at 6% O2 10-40 4 at 3% O2 10-30 at 3% O2 <5 at 3% O2 Notes: 1) Sulphur emissions of oil or coal fired boilers depend on the availability of low-S oil and coal. Certain reduction of sulphur could be achieved with injection of calcium carbonate. 2) Only combustion technology is applied 3) Secondary measures as SNCR are also applied; only larger installations 4) Achieved values when electrostatic precipitators are used 5) When a scrubber is used; only applied to larger installations Emission levels associated with BAT from auxiliary boilers incinerating own bio fuels and/or different fuels are given in Table 6.32. It has to be noted that auxiliary boilers within the pulp and paper industry are of a very variable size (from 10 to above 200 MW). For the smaller only the use of low-S fuel and combustion techniques can be applied at reasonable costs while for the larger also control measures. This difference is reflected in the table. The higher range is considered BAT for smaller installations and is achieved when only quality of fuel and internal measures are applied; the lower levels (in brackets) are associated with additional control measures like SNCR and scrubbers and are regarded as BAT for larger installations. different fuels Bio fuel (e.g. bark) <15 60-100 2 (40-70 SNCR) 3 10-30 4 at 6% O2 different fuels are given in Table 6.32. It has to be noted that auxiliary W). For the smaller only the use of low-S fuel and combustion s difference is reflected in the table. The higher range is considered are applied; the lower levels (in brackets) are associated with tallations. Indication for energy consumption associated with the use of BAT for different types of paper Table 6.33 production per tonne of product Process heat consumption Power consumption Type of mill (net) in GJ/t (net) in MWh/t Non-integrated uncoated fine paper 7,0-7,5 0,6-0,7 Non-integrated coated fine paper 7,0-8 0,7-0,9 Non-integrated tissue mill 5,5-7,5 1 0,6-1,1 Notes: 1) In tissue mills the energy consumption depends mainly on drying system used. Through air drying and creping consumer significant process heat up to 25 GJ/t (according to ETF) BAT Checklist for Non Integrated Paper Mills BREF document December 2001 The checklist is a resume of BREF-document for Non Integrated Paper Mills. There is therefore a need to check BREF-document for a more detailed explanation. BAT reference no. (BREF-document, Section 6.4.2.) BAT definition BAT reference no. BAT status BAT Action Plan Non Integrated Paper Mills General Measures 1 Training, education and motivation of staff and operators 2 Process control optimisation Ensure sufficient maintenance of technical units of paper 3 mills and associated abatement techniques 4 Environmental management system Measures for Reducing Emissions To Water Minimising water usage by increased recycling of process 1 waters and water management 6.3.1 Control of potential disadvantages of closing up the water system. Microbial control, proper design and material selection helps to keep the surfaces in clean condition. Recycle stream monitoring by measurements and lab analysis determine the performance and the quality of the shower water etc. Automation, online measurements and accurate process control area essential for effective and 2 stable papermaking 6.3.2 / 6.3.8 Construction of a balanced white water, filtrate and broke storage system and use of constructions, design and 3 machinery with reduced water consumption when practicable 6.3.3 Measures to reduce frequency and effects of accidental discharge including training of staff and precautionary 4 techniques 6.3.7 Collection and reuse of clean cooling and sealing waters by 5 use of heat exchangers or a cooling tower Separate pre-treatment of coating wastewaters by 6 membrane technique or by flocculation 6.3.6 Substitution of potentially harmful substances by using non toxic and better biodegradable product aids and process 7 chemicals 6.3.12 Effluent treatment of wastewater by installation of equalisation basin and primary treatment ( not considered as 8 BAT as a stand alone technique) 6.3.9 Secondary or biological treatment of wastewater and or in some cases secondary chemical precipitation or flocculation 9 of wastewater 6.3.10 / 6.3.11 Measures for Reducing Emissions To Air 1 Installation of low Nox technology in auxiliary boilers 6.3.15 2 Using low sulphur oil and coal in steam boilers 3 Use of combined heat and power generation 6.3.16 Using renewable sources like wood or wood waste to reduce 4 emissions of fossil CO2 Measures for Reducing solid waste Minimisation of the generation of solid waste and recover, re- 1 use and recycle reusable materials as far as possible Separate collection of waste fractions at source and, if necessary, intermediate storage of residuals/waste, to allow for a greater proportion to be reused or recycled rather than 2 land filled 3 Reduction of fibre and filler losses 6.3.4 Pre-treatment of sludge (dewatering) before further utilisation 4 or final disposal 6.3.13 5 Recovery and recycling of coating wastewaters 6.3.5 Reduction of the amount of waste to be land filled. Identification of possibilities for recovery operations and - if feasible - utilisation of waste for material recycling or 6 incineration of rejects and sludge with energy recovery. Energy saving measures Implementation of a system for monitoring energy usage and performance. Energy management includes setting, controlling, reviewing and revising energy performance 1 targets More effective dewatering of the paper web in the press section of the paper machine by using wide nip shoe 2 pressing technologies (this does not apply to tissue mills) 6.3.17 Use of energy efficient technologies as e.g.. High consistency slushing, best practise refining, twin wire forming, optimised vacuum systems, speed adjustable drivers for fans, high efficiency electric motors, well sizing of electric motors, steam condensate recovery, increasing size 3 press solids or exhaust air heat recovery systems 6.3.18 Reduction of direct use of steam by careful process 4 integration by using pinch analysis Noise attenuation Reduction of noise levels audible in the vicinity of paper mills 6.3.19 Chemical usage D:\Docstoc\Working\pdf\63c8fdaf-34dc-4d47-abb1-8fb57dce0380.xls 10/12/2011 7/8 Ensure the availability of a database for all used chemicals and additives containing information on the chemical composition of the substances, degradability, their toxicity for 1 men and environment and potential of bio-accumulation Application of the principle of substitution i.e. less hazardous 2 products are used when available Measures to avoid accidental discharges to soil and water 3 from handling and storage of chemicals Design and operation of facilities in such a way that 4 dangerous substances cannot escape D:\Docstoc\Working\pdf\63c8fdaf-34dc-4d47-abb1-8fb57dce0380.xls 10/12/2011 8/8
"Non integrated paper mills"