Stuart M. Heisler, P.E. Michael Dejak, P. Eng. Senior Technical Director VP Business Development PARSONS Eco-Tec Inc. Bakersfield, California Calgary, Alberta Presentation for Canadian Heavy Oil Association Conference, Calgary, November 3, 2015
Cal alifornia ifornia Dre reamin amin ’ …. o n such a winter’s day…. The Mommas and the Papas - 1965
Heavy Oil in California Billions of barrels of heavy oil reserves (4.5 API – 13 API in California Steam Injection started in 1964 – Billions of barrels of heavy oil have been produced in 50 years Operators found that the least expensive method for generating steam is by using OTSGs with softened water Current Steam Injection is ~1.5 MM BBL/Day Current EOR production is ~400 M BBL/day Steam-flood SOR ~ 3 - 5 Cyclic Steam Frac SOR ~ 5 - 12
Water and Steam in California Produced water is almost exclusively used for steam generator feed-water since the typical production water cut is 90% Typical Produced Water Quality 5000 – 15,000 ppm TDS 250 – 1500 ppm Hardness as CaCO3 100 – 250 ppm Silica Usually, all of the vapor and liquid is injected downhole In some cases, only vapor is injected, the liquid is used to preheat feed-water and then disposed
Water and Steam in California All of the water used for steam generation is being softened with SAC/SAC or SAC/WAC softeners – no Lime Softening, no Evaporators Older Steam Generators are 62.5 MMBTU/HR single pass running at 65% to 80% Quality Newer Steam Generators are 85 MMBTU/HR dual pass running at 65% to 80% Quality ANSI 900 Generators run 68 BAR, ANSI 1500 run 100 BAR, ANSI 2500 run at 135 BAR
Typical Process Scheme - California Reservoir Water Reservoir 75,000 BPD Water: 135,000 BPD (21460 M3/D) (11,924M3/D) Oil: 15,000BPD (2385 M3/D) 65-80% Steam and water Steam Emulsion IGF Filters SAC/WAC Gen Treating 60,000 BPD Oil (9540M3/D) 100 BPD (16 M3/D) 69,900 BPD 5,000 BPD (11,112 M3/D) (795 M3/D) Disposal Wells
Standard Water Treatment Equipment Horizontal Nutshell Filters SAC/WAC Softeners
Steam Generator Fouling We see very little steam generator fouling – only after water softening upsets Steam generators are pigged every 1 – 3 years California Resources Corporation (OXY) reported only 2 steam generators with boiler tube failures in 8 years with a total of 44 Steam Generators There are no Lime Softeners operating to make soft water for steam generation in California
Advanced Water Treatment Equipment Trend is for increased production from zones with high TDS (6000- 15000 mg/l) and high hardness (500-1200 mg/l as CaCO3) An advanced filter and softener design has been introduced and used at 10 sites over the past 5 Spectrum Filters years Dual Media (Nutshell and Ultra Fine Media) (2 X 30,000 BPD / 4770 M3/D)skids) Key benefits realized are: Reduced OPEX Salt consumption reduced by 50% compared with traditional systems and elimination of HCl and NaOH for WAC regeneration. Reduced CAPEX Integrated construction for minimal site Integrated packed bed SAC/WAC softeners using brine-only counter-current regeneration work, elimination of chemicals handling (30,000 BPD / 4770 M3/D net skid shown)
Case History Requirement : 60,000 BPD (9540 M3/D) treated produced water for steam generator feed to replace existing system (traditional SAC and chemically regenerated WAC) for OPEX reduction. Feed Water : TDS: 9000-11,000 TDS Hardness: 1100 – 1300 mg/l as CaCO3 Silica: 180 mg/l
Case History Results: System commissioned 20 months after order placement. Achieved full rated capacity. Treated Water Quality: Hardness < 0.1 mg/l as CaCO3 OPEX: 30% reduction in salt consumption (8,500 MTPY) 100% elimination of HCl and NaOH consumption Reduced operator attention required CAPEX – OPEX savings justified the system CAPEX to replace an existing 5 yr old system with a 15% IRR.
Typical Process Scheme – Canadian Oil Sands (HLS) Reservoir Retention 7350 BPD Reservoir Water: 45,150 BPD (7178 M3/D) (1170 M3/D) Oil: 15,000 BPD (2385 M3/D) 80% Steam 52,500 BPD (8347 M3/D) Hot Steam Emulsion Filters SAC/ IGF Lime Filters Gen Treating (ORF) WAC Softener Oil 20% Blowdown 100 BPD 50% BD Recycle Makeup (16M3/D) Water 15,215 BPD 1000 BPD 6865 BPD (1090M3/D) (159 M3/D) (2419 M3/D)
Typical Process Scheme – Canadian Oil Sands (Evaporator) Reservoir Retention 7350 BPD Reservoir Water: 45,150 BPD (7178 M3/D) (1168 M3/D) Oil: 15,000 BPD (2385 M3/D) 100 % Steam 52,500 BPD (8347 M3/D) Steam Emulsion Filters IGF SAC Evaporator Gen Treating (ORF) Oil 100 BPD Makeup 5% Blowdown (16 M3/D) Water 1000 BPD 11,000 BPD 2760 BPD (439 M3/D) (159 M3/D) (1749 M3/D)
What if………. ….the California water treatment experience were applied in Western Canada?
…and you could go from this… Reservoir Retention 7350 BPD Reservoir Water: 45,150 BPD Oil: 15,000 BPD 80% Steam 52,500 BPD Hot Steam Emulsion Filters SAC/ IGF Lime Filters Gen Treating (ORF) WAC Softener Oil 20% Blowdown 100 BPD 50% BD Recycle Makeup Water 15,215 BPD 1000 BPD 6865 BPD
…to this… Reservoir Retention 7350 BPD Reservoir Water: 45,150 BPD Oil: 15,000 BPD 80% Steam 52,500 BPD Steam SAC/ Emulsion Filters IGF Gen WAC Treating (ORF) Oil 20% Blowdown Flash distillate 100 BPD Makeup Water 50% BD Recycle 15,215 BPD 1000 BPD 6865 BPD
Proposed Process Scheme – Canadian Oil Sands (ZLS) Reservoir Retention 7350 BPD Reservoir Water: 45,150 BPD Oil: 15,000 BPD 80% Steam 52,500 BPD Steam SAC/ Emulsion Filters IGF Gen WAC Treating (ORF) Oil 20% Blowdown Flash distillate 100 BPD Makeup 50% BD Recycle Water 15,215 BPD 1000 BPD 6865 BPD
Proposed Process Scheme – Canadian Oil Sands (ZLS – high efficiency) Reservoir Retention 7350 BPD Reservoir Water: 45,150 BPD (7178 M3/D) (1168 M3/D) Oil: 15,000 BPD (2385 M3/D) 90% Steam 52,500 BPD (8347 M3/D) Steam SAC/ Emulsion Filters IGF Gen WAC Treating (ORF) Oil 10% Blowdown 100 BPD Makeup Blowdown (16 M3/D) Water Treatment 75% BD Recycle 9910 BPD 1000 BPD (1576 M3/D) (159M3/D) 1460 BPD (232 M3/D)
Proposed Water Treating for SAGD Use SAC/WAC softeners and OTSGS to make 80-90% Quality Steam for the least expensive Capex and Opex Dispose of the SAC/WAC Regen (1-5% of total water) Separate the steam blowdown, preheat the generator feed-water, then treat the High TDS, High Silica, Low Hardness water in an evaporator. Dispose of the evaporator blowdown (25% of evaporator inlet, 5% of total water) Minimizing evaporator use minimizes total GHG emissions
Potential Benefits CAPEX reduction TIC CAPEX estimate* for 60,000 BPD (9540 M3/day) boiler feed water capacity systems (CDN $ millions) Evaporator HLS/SAC/WAC SAC/WAC 50-70 26-30 14-16 * All systems include skim tank, DGF, ORF
Potential Benefits CAPEX reduction OPEX reduction Compared with HLS/IX expected to be in the range of $500K to $3000K/yr for 60,000 BPD (9540 M3/day) depending on water chemistry, balance, waste considerations Operability less equipment = simpler system =easier to operate Directive 81 compliance – can be achieved Waste disposal – various configurations possible to optimize depending on disposal options GHG emissions – to be determined but less than evaporation and expected to be less than HLS/IX
Why Why no not? t? The concern over “silica scaling” of the OTSG
California experience 1. Scale is not silica but silicates of multivalent cations (Ca, Mg, Fe,…) Silica = SiO 2 Calcium Silicate = Ca 2 SiO 4 Magnesium Silicate = Mg 2 SiO 4 Iron Silicate = Fe 2 SiO 4 This is also true in Western Canada
California experience 2. Principle of scale control: Keep treated water hardness consistently low to eliminate formation of silicates (ideally < 0.1 mg/l as CaCO3) This is supported in theory – scale prediction simulations (e.g. OLI) consistently predict very little scale formation even with high (i.e. 300 mg/l Si) when multivalent cations (i.e. hardness) are low Without a lime softener, there is never any “release” of fine silicate particles that can pass through to the OTSG or that can foul and impede ion exchange softener performance
Conclusion Application of lessons learned from the California experience Potential for significant reduction in CAPEX and OPEX in water treatment systems for SAGD operations from ZLS “zero lime softening” Advanced water treatment systems Improved operability from simplified systems Potential for economical AER Dir 81 compliance, reduced waste disposal and reduced GHGs
Thank You Questions???? Stuart M. Heisler, P.E. Michael Dejak, P.Eng. PARSONS Eco-Tec Inc. Stuart.Heisler@Parsons.com mdejak@eco-tec.com
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