DISPOSAL & RE-REFINING OF USED LUBRICATING OIL

1. DISPOSAL & RE-REFINING OF USED LUBRICATING OIL G.S.Dang & M.O. Garg Indian Institute of Petroleum Dehradun –248005 23rd August-2003

2. Presentation Outline • Introduction • Used oil contaminants/ composition • Disposal practices • Re-refining of used lubricating oils • Economics of re-refining • Observations/Recommendations

3. Introduction • Lube oil - Highest value component of crude oils. • Applications in automotives & industries. • Prolonged use causes degradation/ contaminants of lube oils. • Degraded oils, not fit for intended use, are discarded - referred as used oils. • Used oils usually contain toxic substances making them hazardous products. Contd..

4. Introduction (contd.) • Negative environmental impacts/public health hazards are associated with the improper storage, handling, transportation, treatment and disposal of used lubricating oils. • Adverse impact on human health & environment demands effective management of used lubricating oils.

5. Introduction (contd.) • Used lubricating oil being a resource, effective management of it encourages: - Conservation of resources - Minimization of waste • One gallon of used oil can pollute more than one million gallons of drinking water Recycling/ Re-refining it into reusable products can prevent damage to land, air, water and health. • Recycling used oil(s), rather than letting it enter the waste stream , is the best way to handle/ manage it.

6. Used Oil Contaminants/Composition USED OIL includes: - Engine Oil: Typically crankcase oils from automobiles, trucks etc. - Transmission fluid & - Spent industrial oils, removed from equipments or machines. Contd..

7. Used Oil Contaminants/Composition (contd..) Contaminants in used lubricating oils (Automotive & Industrial) - Heavy metals e.g. lead, arsenic, cadmium, chromium, nickel, copper, zinc etc. - Halogenated solvents - Polychlorinated biphenyls (PCBs) - Polyaromatic hydrocarbons (PAH) including benzene. - Fuel components, sediments and water. Contd..

8. Used Oil Contaminants & their hazards Contaminant Source Hazards Lead Gasoline, Metal fatigue Bearings PNAs/PAHs Combustion Carcinogenic products Metals Additives & Toxic ( Zn, Cd, Cr, Engine Wear Ni, etc) Halogenated Cleaning Flammable solvents solvents PCBs Insulating Oils Toxic Particulates Combustion Breathing products & Problem sediments

9. Used Oil Contaminants/Composition (contd..) Typical Composition Of Used Oil Components Wt% (approx) Water 5-9 Light ends 2-4 Gas oil 4-7 Base oil 75-64 Residue 13-17

10. Disposal Practices • Unacceptable practices • Acceptable practices

11. Unacceptable practices • Dumping to ground, watercourses, sewers, drainage system etc. • Burial • Use for dust control, weed abatement, timber preservation by painting, pest control etc. Contd..

12. Unacceptable practices (contd..) • Placing used oil in garbage bins. • Open air burning, incomplete combustion ( short residence low temperature burning) of used lubricating oil. • Any other processing of used lubricating oil causing pollution exceeding statutory requirements. • Any discharge of residues generated from processing of used lubricating oils. • Other practices in which the used oil may cause or have impact on humans, plants, animals, or other organisms.

13. Acceptable practices • Reconditioning of used oils by removing impurities. This form of recycling might not restore the oil to its original condition but it prolongs its life. • Reconditioned oil can be delivered to petroleum refinery and introduced as a feed stock into the front end of refinery process. Contd..

14. Acceptable practices (contd..) • Re-refining used lubricating oils to recover base oil or other petroleum fractions as long as the processes and their products are environmentally sound • Used oil processing to remove water and particulates so that it can be burned as fuel to generate heat or to power industrial operations. Not a preferred form of recycling because it enables the oil to be reused only once. Contd..

15. Acceptable practices (contd..) • Recycling through Re-refining- A preferred option since the oil is used number of times. The key is – base oil does not wear out; it can be recycled over and over again-Resource Conservation. Other benefits includes: - Reduces pollution threat. - Reduce dependence on imported oil. - Re-refining is energy efficient. - Provides direct and indirect employment.

16. Re-refining of used lubricating oils • Countries all over the world including United States, UK, France, Italy, Canada, India, South Africa, Israel, Australia and New Zealand etc. re-refine used oils into lubricating oil base stocks. • Regulations/Rules to handle and process used oil(s) exist in each of these countries. Contd…

17. Re-refining of used lubricating oils (contd..) • MoEF, New Delhi has categorized used lubricating oil as hazardous product and to be handled/disposed off as per HW Rules. • Specifications for used oils suitable for Re-refining/Recycling in India are listed as below [Notified in hazardous waste (Management and Handling) Amendment Rules 2003, Schedule 5 & 6]

18. Specifications for used oil suitable for Re-refining (Schedule-5) Sr. No. Parameters Maximum permissible limit • Colour 8 hazen units • Water 15% • Density 0.85-0.95 • Kin. Viscosity 1.0-32.0 (cSt @ 100 0 C) 5. Diluents 15% vol 6. Neutralization No. 3.5 (mg KOH/g) Contd..

19. Specifications for used oil suitable for Re-refining (Schedule-5, contd..) Sr. No. Parameters Maximum permissible limit 7. Saponification value 18 (mg KOH/g) 8. Total halogens, ppm 4000 9. PCBs ND 10. Lead, ppm 100 11. Arsenic, ppm 5 12. (Cd + Cr + Ni), ppm 500 13. Polyaromatic 6% (v/v) Hydrocarbons (PAH)

20. Specifications for waste oil suitable for Recycling (Schedule-6) Sr. No. Parameters Maximum permissible limit 1. Sediment 5% 2. Heavy metals, ppm 605 ( Cd + Cr + Ni + As +Pb) 3. Polyaromatic 6% (v/v) Hydrocarbons (PAH) 4. Total Halogens 4000 5. Polychlorinated ND biphenyls (PCBs) *Waste oil: Unsuitable for re-refining , but can be used as fuel in furnaces, if meets specifications laid down in Schedule-6 Contd..

21. Re-refining of Used Oils • Motor/Automotive Oils • Industrial Oils

22. Re-Refining of Motor oils • Modernlubricating oils are based upon oils refined from crude oil/petroleum, synthetic oils or mixture of two. • Blended with additives to extend range of operating temperatures, to keep solids in suspension & to discourage formation of deposits. Contd…

23. Re-Refining ofMotor oils (contd..) • Regardless of the base oil and additives, all lubricating oils eventually become contaminated through use with substances that are threat to the environment. • Contaminants arise out of various reactions occurring in lube oils during use e.g. oxidation, cracking, decomposition of polymeric materials, organo-metallic compounds and polymerisation of hydrocarbons, etc. Diluents like fuel, water and antifreeze also accumulate while metal content of used oil is also important besides polynuclear aromatics. Contd…

24. Re-Refining ofMotor oils (contd..) • The degraded oil is drained out of equipment / engine – replaced with fresh stock. • With advancement in engine design and improvement in quality of lube oils, the drains intervals have been prolonged substantially.

25. Re-refining of Motor Oils (contd..) • Used Motor Oils include: • Vehicle Crankcase Oil • Engine Lubricating Oil • Transmission Fluids • Gearbox Oils • Motor oils undergo an extensive rerefining process to remove contaminants such as dirt, fuel, water, and degraded additives to produce a good – as new base oil. Contd…

26. Re-refining of Motor Oils (contd..) • No compromise in quality of re-refined oil. • Base oil blended with addive packages to produce lubricants such as - Motor oil - Transmission fluid - Greases Contd..

27. Re-Refining of Industrial Oils • Used Industrial oils include: - Hydraulic oils - Compressor oils - Turbine oils - Bearing oils - Gear oils - Transformer (electrical)oils Contd…

28. Re-Refining ofIndustrial Oils(contd..) - Refrigeration oils - Metal working oils - Rail road oils • Used Industrial oils generally have minimal contamination and hence can be cleaned up with simple process steps (Reclaiming) for example used oils such as Hydraulic oils , transformer oils are heated to evaporate moisture followed by simple filtration to get relatively clean products to be re-used. Contd…

29. Used Oil Re-refining Technologies

30. Used Oil Re-refining Technologies (contd.)

31. Used Oil Re-refining Technologies (contd.) • MoEF , New Delhi, India has approved only the following re-refining technologies being more environment friendly: - Vacuum distillation followed by Clay treatment. - Vacuum distillation followed by Hydro- treating. - Thin film evaporation process or - Any other technology approved by MoEF.

32. Fuel Stripping Dehydration Vacuum distillation or Solvent extraction Lube oil base Stock Finishing Clay/ Hydro finishing General Re-refining Scheme Used oil

33. Economics of Re-refining • Re-refined oil prices comparable to equivalent virgin oil product pricing. • Re-refined oil prices are affected by following variables: - Used oil feed stock cost - Availability - Transportation cost - Re-refining process used Contd…

34. Economics of Re-refining (contd..) - Regulatory compliance to dispose off residues. - Scale of operation • Other points which also affect economics are: - Crude oil prices - Residue/bottom disposal cost and - Clean up liability • Re-refining processes are economically viable only with larger capacities Contd..

35. Economics of Re-refining (contd..) • Barriers to profitable environment friendly used oil re-refining : - High capital cost of equipment - High operating cost - Environment treatment problems - Large collection costs - Hydrotreating re-refined oil

36. Collection/Storage of Used Oils

37. Collection/Storage of Used Oils For used oils to be re-refined properly/economically it is essential that different types of oils are collected/stored separately • Used oil is usually stored in above ground containers. • No contamination of used oils with other wastes such as halogenated solvents etc. Contd…

38. Collection/Storage of Used Oils (contd..) • Label all containers and tanks as “ Used Oil” & keep them in good condition. • Rusting of tanks, leakage deterioration not to be allowed. • Store used oil in areas with oil impervious flooring and secondary contaminant. • Tanks and/or containers of used oil should be placed in weather proof area and should be kept away from incompatible materials

39. Availability of Used Oil • 200-300 TMT/ year of used lubricating oil is estimated to be generated in India. • Bulk of used lubricating oil is generated by: - State Road Transport Corporation - Railways - Large fleet operators - Defence establishments - Steel plants

40. Observations/ Recommendations • Used oil is the valuable resource – need to be managed properly. • Re-refining is the most appropriate way to recover quality lube oil base stock. • Acid- clay re-refining process is being phased out and more environmental friendly re-refining technologies are taking its place. Contd..

41. Observations/ Recommendations(contd..) • Lubricating oil base stocks produced from modern re-refining technologies have performance parameters equivalent to virgin base stock for use in engine oils, hydraulic fluids, gear lubes and other lubricant applications • The quality of used oil plays important role in process economics so proper collection of used oil is to be ensured. Also special attempts are required to collect at least 50% of the consumption of fresh lube oils (Collection at present is just 20%). Contd..

42. Observations/ Recommendations(contd..) • Since PCBs and PNAs/PAHs presence make used oil unsuitable for re-refining. Therefore care should be taken during used oil collection/ storage to avoid mixing of these. • There seems to be good prospect for using re-refining processes based on vacuum / Thin film distillation followed by clay/ hydrofinishing. However with hydrofinishing economical viable capacity of re-refining unit is generally higher- around 10,000 tonnes per annum • Incentives to be given to used oil generators/collectors and processors for making re-refining industry a progressing one.

43. Thank You