Presentation on theme: "Alkali metal reduction (sodium reduction). Status & POPs application Process has been used commercially for approximately 20 years. It has been used extensively."— Presentation transcript:
Status & POPs application Process has been used commercially for approximately 20 years. It has been used extensively in particular in North America, France and in Germany where most of the oil above 50 ppm now has been treated POPs application: PCB-contaminated oils up to 10,000 ppm and for Askarel transformers (>10,000 mg/kg of PCBs)
Alternative 1 : Direct operation mode with transformer P01 : Feeding pump with contaminated oil P04 : Feeding pump of the de-watering devices P16 : Filter press pump P18 : Dewatered oil discharge pump Transformer Mobile unit R01 : Nitrogen cylinder S03 : Nitrogen production device V : expansion tank V P01 P18 R01 P04 S03 P16
Alternative 2 : Indirect operation mode using intermediate oil tank P01 : Feeding pump with contaminated oil P04 : Feeding pump of the de-watering devices P16 : Filter press pump P18 : Dewatered oil discharge pump R01 : Nitrogen cylinder S03 : Nitrogen production device V : expansion tank Transformer Mobile unit Storage Tank R01 P18 P01 P16 P04 S03
PART I : Adaptation Technology – Country A. Performance: 1. Minimum pre-treatment: De-watering to avoid explosive reactions with metallic sodium. Drying oil is normally accomplished to achieve a moisture content of approximately 100 ppm 2. Destruction Efficiency: DE nor DRE has been reported (DE typically 99% - 99.9% in most applications, it is also possible to go to a much higher DE DE values of greater than 99.999 percent reported for chlordane and HCB (Ministry of Environment of Japan, 2004
PART I: Adaptation Technology - Country A. Performance: 3. Toxic by-products: Salt solution contains some oil and biphenyl polymer. Analysis for to dioxins and furans and have been found to be innocuous. Residue can have a high ph because of the presence of NaOH or KOH. Air at vent routinely analysed for PCB, chlorobenzene + other organic compounds in Canada. PCB at the vent must be < 1 microgram/m3 in Canada. 4. Uncontrolled releases: Steel pan under process equipment collect any leak from piping + vessels. Hoses between units +tanks+ transformers are typically wrapped with sorbent material at connections are underlain by plastic liner 5. Capacity to treat all POPs: PCB-contaminated oils up to 10,000 ppm and for Askarel transformers (>10,000 mg/kg of PCBs) 6. Throughput: quantity [tons/day, l/day] Wide range: Mobile facilities are capable of treating 15,000 litres per day of transformer oil. For mobile DCR units average flow rate 1000 L/hr.
PART I: Adaptation Technology - Country A. Performance: 7. Wastes/residuals: Secondary waste stream volumes: Residues include sodium chloride, sodium hydroxide, polyphenyls and water, sometimes solidified polymer. Separation of by-products: Re-use decontaminated oil (after treatment) and organo- metallic reagent re-used. Rest NaCl + Small amount sludge generated contains NaCl + solidified polymer with some oil and water normally solidified and directed to approved landfill Off gas treatment: nitrogen and hydrogen gas + organic compounds relatively minor finally treatment by granular activated carbon
PART I: Adaptation Technology - Country A. Performance: Complete elimination: Certain limits : In case decontaminated oil is circulated in transformer and returned to treatment unit, a certain amount of cleansing of the internals of the PCB transformer takes place, especially if the transformer remains in operation; some of the PCB in the porous constituents gets desorbed in the hot clean oil that returns to the treatment unit; (no reagent is directed to the transformer). Lot of experience on: % decontamination in transformers after on-line treatment + leach back etc.
PART II: Adaption Country – Technology A. Resource needs: 100, 200, 300 DCR mobile Unit Canada Power requirements: 60 Amp at 575 V Water requirements: none Fuel volumes: none Reagents volumes: 200 kg Weather tight buildings: yes Hazardous waste personnel requirement: Sampling requirements/facilities: lab module GC Peer sampling: Laboratory requirements: Communication systems: Number of (un/skilled) personnel required: 2 (1 skilled)
PART II: Adaption Country – Technology B: Costs for: 0.15 US$/l low PCB, 0.7 /high PCB Installation + commissioning: --- Site preparation: --- Energy & Telecom installation: --- Compliance:--- Reporting: --- Run without waste:--- Run with waste:--- Decommissioning: --- Landfilling:--- Transport residues:---
PART II: Adaption Country – Technology C. Impact & D. Risks Discharges to air: --- Discharges to water:--- Discharges to land:--- Risks reagents applied: explosion dispersed metallic sodium can react violently with water lot of measures Risks of technology: fire scenarios Operational risks: water contact, electricity safety features
PART II: Adaption Country Technology E. Constructability & F. Output Ease of installation & construction of plant: standard units Ease of shipping/transit: container sized units
Ease of operation: environment + safety training + on the job training Ease of processing: continuing process units for transformer oil Generated waste (% of input waste):--- Deposited waste at landfill (% of input waste): Waste quality properties (pH, TCLP)
Experiences France: Mobile system Exhaust of electrofilter (purification gases)
Italy: mobile treatment transformer 7.5 tons oil from transformer Treated total 45 tons!!
Proven long time experience for PCB’s Fire need for high quality risk management Flexible treatment at site possible With continuous treatments limits on total cleaning Mobile units Lower and higher quantities possible Minimum interference for transformers Strength’sWeaknesses