Environmental Control at Dow Sarnia: Challenges and Solutions

1. Environment Presentation to CBE 497 By R.A. Hawrelak 12 Feb, 2002

2. Outline • EH&S Department at Dow in Sarnia. • 1969 MOE Charges Dow with 100+ Violations – PO Plant Example. • pH Control Problem and Solution. • Mixing for pH Control. • API Storage Tank Venting Problem. • Recent Nova Benzene Spill.

3. Environmental, Health & Safety • Environmental Control Mgr (PEng) • 3 Process Engineers (PEng) • 3 Technicians (Fish Pond + Field sampling) • 1 Industrial Hygienist (BSc.) • Health Manager (Dr.) • 3 Nurses • Safety and Loss Prevention Mgr (PEng) • 3 Process Engineers (PEng) • Emergency Response Co-ord (PEng) + Selected Group • Fire and Security Department • Transport. Emerg. (Plant Foreman + Selected Operators)

4. 1969 Dow Blue Book • MOE Charged Dow with over 100 violations in 20 Chemical Plants • Greatest Problems found in the Old PO Plant. • White Streak CaCO3 in the St Clair River. • CaCO3 Land Fill problem. • PDC, DCIPE discharge to St Clair River. • pH problem in hyrdrolyzer effluent. • Cl2 discharge to atmosphere. • C3H6 and C3H8 discharge to atmosphere. • Explosions in Degasser.

5. New Propylene Oxide Process

6. PO Reactions • Cl2 + C3H6 + H2O > PCH + HCl • PCH + HCl > PDC + H2O (Waste) • PDC + Cl2 > DCIPE + HCl (Waste) • PCH + NaOH > PO + NaCl + H2O • HCl + NaOH > NaCl + H2O (pH Prob) • PDC, DCIPE, NaCl, H20, NaOH &/or HCl to Special BIOX Plant

7. pH Control on the Internet

8. This is Poor pH Control

9. pH12 to 2 Is A Control Problem

10. Multiple Tank Solution

11. Good pH Control • Small tank control to pH 9.6 • 2nd tank 20 times larger than first tank and controls pH to 8.3. • 3rd tank is 20 times larger again and controls pH to 7.0 • Very costly and takes lots of operator attention. • Check real time pH control on Internet.

12. Mixing for pH Control • RAH CD File on Mixing. • Sizing of Tank and Agitator • Blending Example 1. • pH Control example 2. • Draft Tube for agitator free mixing.

13. API Storage Tank Venting • Venting problem during Pump In. • Venting problem as temperature rises during the day. • Benzene classified as a carcinogen. • MOE regulation went from 3 ppmv at company fence line to 1 ppmv at point of impingement. • Initially Eng’g showed 674,000 lbs lost/yr. • BLOSS Finally showed 122,000 lbs lost/yr. • Installed new , stronger tank & burned vents.

14. Loading Logistics

15. Average Daily Temperatures

16. Tank Levels

17. Nova Benzene Spill • Dec 16, 2000, 8:45 AM detected odour. • 1 inch line split spilling benzene, toluene and xylene – leak found and corrected. • 6 inch line split goes undetected for 12 hours spilling 1,000,000 litres of benzene (30%) and toluene (70%). • Dow operator notifies Nova of Spill. • Spill detected and stopped. • Line failure due to water hammer or failure to turn off line steam tracing on blocked flow (liq expansion).

18. Nova Benzene Spill cont’d • No emergency response warnings given to Corunna and Froomfield residents. • Over 100 residence received high dose of benzene. • 10 operators exposed to extremely high benzene exposure (2% by vol). • Leukemia now known to be “Triggered” by high benzene exposure in rats. In past ten years, 3 operators have died with leukemia.

19. Nova Conducts Studies • Nova cannot determine evaporation rates. • RAH asked for help. • 1,000,000 litres. • 6 inch depth. • 164 ft. by 427 ft. • 3.3 mph wind. • 19,533 lb/hr evaporation rate. • 98 hours to evaporate. • Did not apply foam till after 2 days.

20. Recent Spills In Sarnia • Nova could be facing $2MM in fine after being charged for Dec 16, 2000 spill. • $2MM charge to Shell for Mar 8, 2000 spill. • $1MM charge to Ceda-Reactor,a contractor at Shell. • $0.32MM charge to Dow on March 22, 2000 for latex plant spill. • Sarnia CAER head replaced.

21. End of Presentation. • Good luck on applying environmental aspects to your final report.