Extraction Process Design Basis

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1 AI Project Update Joslyn North Mine Project 5 Process 5.1 Introduction This section describes the project bitumen extraction process and includes: process description material balance energy balance technology pilot testing plant location and layout For a description of the design considerations for the extraction process described in this section, see Section Process Description During the bitumen extraction process, oil sands delivered from the mine are crushed and mixed with hot water and thoroughly agitated. The resulting slurry is pumped to the froth production plant, where a bitumen-rich froth is recovered. The balance of the oil sands slurry is processed in dewatering equipment, which separates the slurry into warm water that is recycled in the plant and into hydrocyclone underflow (coarse sand tailings) and thickener underflow (thickened tailings [TT]). The bitumen-rich froth is deaerated, mixed with a solvent and separated in the froth treatment plant into a clean, partially deasphalted, diluted bitumen product and a tailings stream. The froth treatment tailings (FTT), from which solvent has been recovered, are pumped to a tailings pond. Recovered solvent is recycled. The diluted bitumen product is stored in tanks before shipment. The oil sands processing facilities will be designed to process 8600 t/sh of oil sands ore, yielding about 100,000 barrels per calendar day (bpcd) of partially deasphalted bitumen product. For the design basis of the extraction process, see Table For a simplified flow diagram of the extraction process, see Figure For the design considerations and rationale for the extraction process, see Section Table Extraction Process Design Basis Characteristic Design Basis Bitumen production 100,000 bpcd Availability 90% Feed rate (low, average, high-grade) 8600 t/sh Feed grade properties 8.6% to 12.2% Asphaltene rejection 7% Asphaltene in bitumen 18% Extraction temperature 50 C Froth treatment High-temperature paraffinic TOTAL E&P Joslyn Ltd. February 2010 Page 5-1

2 Table Extraction Process Design Basis (cont d) AI Project Update Characteristic Target Froth treatment temperature 70 C 90 C Solvent loss ratio in tailings (vol/vol) 4/1000 Tailings solvent recovery Solvent:Bitumen ratio Froth production Froth treatment design capacity Ore Preparation Process For the ore-preparation process schematic, see Figure Ore Crushing and Conveying Two-stage 1.5 w/w Conventional 130 kbpsd The oil sands ore is crushed and converted to slurry before being transported from the mine to the extraction plant. The ore is delivered by truck to two crushers, each with a capacity of 11,000 t/sh. The crushing system reduces the run-of-mine material to a smaller size (400 to 600 mm), after which it is stored in a surge bin and transferred by conveyor to the slurry preparation unit Slurry Preparation Material from the surge bin is fed to a conditioning drum, in which warm process water is added to convert the dry ore to a slurry. The conditioning drum contains an ablation section and a perforated segment that acts as a wet screen to separate the reject material. The rejected material is reprocessed to maximize bitumen recovery. Slurry is transported to the froth production plant through hydrotransport slurry lines that are approximately 1600 m long. The slurry preparation and hydrotransport design includes three pipelines, each with a capacity of 4300 t/sh Froth Production In froth production, bitumen is separated as froth from the conditioned oil sands slurry received from slurry preparation. The slurry is processed in two froth production trains, each with a capacity of 4300 t/sh. The froth production process incorporates industry-standard processes, including: a primary separation cell (PSC) that produces a froth product, a middlings stream and a coarse sand tailings product hydrocycloning of the PSC underflow, which produces a coarse sand tailings product recovery of bitumen by flotation from the middlings stream and from the hydrocyclone overflow a deaeration unit The PSC is operated at 50ºC, which ensures bitumen recovery targets are achieved, considering the uncertainties related to ore processing. With operational experience and plant optimization, the temperature could be reduced to optimize energy efficiency. For an illustration of the froth production process, see Figure For a description of the design considerations in the froth production process, see Section February 2010 Page 5-2 TOTAL E&P Joslyn Ltd.

3 AI Project Update Figure Simplified Extraction Process TOTAL E&P Joslyn Ltd. February 2010 Page 5-3

4 AI Project Update Figure Ore Preparation Process Schematic February 2010 TOTAL E&P Joslyn Ltd. Page 5-4

5 AI Project Update Figure Froth Production Schematic TOTAL E&P Joslyn Ltd. February 2010 Page 5-5

6 AI Project Update Froth Treatment During froth treatment, bitumen froth from froth production is mixed with a paraffinic solvent (C5) to precipitate asphaltenes and improve product quality. The froth is processed in two froth treatment trains, each operating at a maximum capacity of 65,000 bbl/d. The froth treatment plant includes a: two-stage countercurrent froth-settling circuit two-stage tailings solvent recovery unit (TSRU) circuit solvent recovery unit (SRU) A high-temperature (70 C to 90 C) paraffinic process technology will be used to recover solvent from the partially deasphalted bitumen in the SRU. (For a summary of the asphaltene rejection assumptions, see Section ) The source of start-up solvent will be finalized during future engineering studies. Makeup solvent is recovered from the return diluent batch from an offsite upgrader and processed onsite in a depentanizer unit. The SRU recovers the solvent from the froth treatment tailings and includes two identical columns. In the event one column is not operational, the second will process the froth treatment tailings. Solvent losses to the tailings will average 4 volumes per 1000 volumes (4/1000) of dry bitumen produced. The second-stage column underflow is pumped to the tailings pond. For an illustration of the froth treatment process, see Figure For a description of the design considerations in the froth treatment process, see Section Asphaltene Rejection The primary goal of the paraffinic froth treatment process is to create a bitumen product suitable for use in upgraders or refineries. The relationship between product quality and asphaltene rejection rate is being further refined through pilot plant testing (see Section 5.5.3). For a description of the asphaltene rejection assumptions in the froth treatment process, see the responses to: June 2007 SI EUB SIR 70a to 70g October 2007 Secondary EUB SIR 12a to 12c December 2007 Third Round EUB SIR 2a to 2d TEPJ is evaluating methods to separate the asphaltene from the froth treatment process to optimize resource recovery and assessing alternative uses for the recovered product. Based on an average 18% asphaltene content in the bitumen feed, an average asphaltene rejection rate of 7% is projected to meet product quality goals and maximize resource value. February 2010 Page 5-6 TOTAL E&P Joslyn Ltd.

7 AI Project Update Figure Froth Treatment Schematic TOTAL E&P Joslyn Ltd. February 2010 Page 5-7

8 AI Project Update Tailings Process Both TT and coarse sand tailings are produced in the froth production process, and tailings containing hydrocarbon and solvent are produced in the froth treatment process. The tailings system includes: a coarse sand tailings stream from the hydrocyclone underflow a TT stream from the thickener underflow froth treatment tailings stream from the TSRU underflow The coarse sand tailings stream is pumped to a sand beach area. Runoff water from the beached sand, which contains fines known as fluid fine tailings (FFT), is pumped to a centrifuge system to recover the water and consolidate the fines. The thickener produces TT and facilitates warm-water recovery. Recovery of the warm water in the thickeners results in considerable energy savings and reduces the requirement for river water. The TT product is 50% solids when deposited and will be beached in designated disposal areas. The TSRU tailings are pumped and deposited separately from the TT. For information on the deposition strategy for tailings products, see Section 6. For a description of refinements to, and design considerations in tailings process and disposal, see Section Extraction Production Capacity and Availability The overall production index, which is based on the anticipated final calendar day production divided by the stream day capacity of the froth production plant, is estimated at 90%. The calendar day material balances are based on this value. Simulations were done to assess the benefits gained from the froth tank, which is filled when froth production is processing high-grade ore. Froth tankage will be drawn down by the froth treatment plant when froth production is processing low-grade ore. For a summary of the installed capacity and projected availability of the extraction process, see Table Table Area Overall Extraction Production Capacity and Availability Trains x Maximum Installed Capacity Oil sands truck and shovel 98.7 Crushing Conveying 2 x 11,000 t/sh 2 x 11,000 t/sh System Availability (%) 99.8 Slurry preparation 3 x 4300 t/sh 98.6 Hydrotransport system 3 x 4300 t/sh 99.9 Froth production Bitumen recovery Thickeners Coarse tailings pipelines Thickened tailings pipelines Froth treatment Bitumen processing Tailings 2 x 4300 t/sh 2 x 4500 m 3 /sh 3 x 4500 m 3 /sh 2 x 5000 m 3 /sh 2 x 65,000 kbpsd 2 x 1000 m 3 /sh Overall Production Index February 2010 Page 5-8 TOTAL E&P Joslyn Ltd.

9 AI Project Update Joslyn North Mine Project 5.3 Material Balance Stream day material balances were based on a throughput of 8600 t/sh and were developed for the following operating scenarios: high-grade ore processed during summer conditions (see Figure 5.3-1) average-grade ore processed during spring/fall conditions (see Figure 5.3-2) low-grade ore processed during winter (see Figure 5.3-3) For the calendar day balance for average-grade ore, see Figure Energy Balance Extraction Thermal Energy Consumption For the basis for estimating thermal energy requirements, see Table Table Basis for Estimating Thermal Energy Demands Spring/Fall Summer Winter Inlet Temperatures ( C) Oil sands Raw water River water Makeup solvent Process Temperatures ( C) Slurry preparation Temperature loss across thickener Froth treatment settlers 70/90 70/90 70/90 SRU TSRU NOTES: SRU = Solvent recovery unit. TSRU = Tailings solvent recovery unit. TOTAL E&P Joslyn Ltd. February 2010 Page 5-9

10 AI Project Update Figure High-Grade Stream Day Summer Case February 2010 Page 5-10 TOTAL E&P Joslyn Ltd.

11 AI Project Update Joslyn North Mine Project Figure Average Grade Stream Day Spring/Fall Case TOTAL E&P Joslyn Ltd. February 2010 Page 5-11

12 AI Project Update Figure Low Grade Stream Day Winter Case February 2010 Page 5-12 TOTAL E&P Joslyn Ltd.

13 AI Project Update Joslyn North Mine Project Figure Average-Grade Calendar Day TOTAL E&P Joslyn Ltd. February 2010 Page 5-13

14 AI Project Update For the thermal energy balance through the extraction plant for average-grade oil sands processed under spring/fall conditions, see Table Table Thermal Energy Flows for Spring/Fall Average-Grade Heat to Froth Handling and Treatment Deaerator SRU 1 st -stage flash drum heater SRU column heater SRU steam stripping TSRU steam stripping Depentanizer reboiler Recycle water trim heater Total Heat to Water Heat exchange with froth treatment Steam/water exchangers Total Steam Consumption Direct exchange with water Froth treatment Total (GJ/sh) (GJ/sh) (GJ/sh) NOTE: 8600 t/sh = two trains. For the fuel consumed per unit of bitumen produced for the three operating scenarios, see Table The primary use for diesel is for mine equipment and the primary use for natural gas is for electric power and steam generation. Gasoline will not be used during mining operations. Table Fuel Required for Processing (Two Trains) Operating Scenario Bitumen Production (m 3 /sh) Diesel (GJ/sh) Natural Gas (GJ/sh) Total Fuel Required (GJ/m 3 bitumen) High grade, summer Average grade, spring/fall Low grade, winter NOTES: Summary of fuel used for moving ore, producing steam and generating electricity, including surplus electrical energy exported. sh = Stream hour Total Mine and Extraction Energy Balances For total mine and extraction energy balances for the three stream day operating scenarios, see Figure to Figure For the calendar day average energy balance, see Figure February 2010 Page 5-14 TOTAL E&P Joslyn Ltd.

15 AI Project Update Figure Energy and Heat Balance Stream Day Summer High-Grade Ore TOTAL E&P Joslyn Ltd. February 2010 Page 5-15

16 AI Project Update Figure Stream Day Energy and Heat Balance Spring/Fall Average-Grade Ore February 2010 TOTAL E&P Joslyn Ltd. Page 5-16

17 AI Project Update Figure Energy and Heat Balance Stream Day Winter Low-Grade Ore TOTAL E&P Joslyn Ltd. February 2010 Page 5-17

18 AI Project Update Figure Energy and Heat Balance Calendar Day Average-Grade Ore February 2010 TOTAL E&P Joslyn Ltd. Page 5-18

19 AI Project Update Joslyn North Mine Project 5.5 Technology Pilot Testing Pilot tests have been completed to validate technology selected for the project. Test objectives included enhancing: tailings management froth production and recovery operating reliability energy efficiency environmental performance cost The following sections outline the pilot testing program Froth Production Pilot Completed Testing The froth production pilot focused on refining the design criteria for the following components: flotation sand separation with cyclones fine tails treatment with thickeners pipe loop testing (rheology) on TT This pilot generated feedstock for the froth production tailings pilot (TT and FFT). Planned Testing Planned froth production pilot testing includes bench thickener tests to assess water chemistry and ore variability Froth Production Tailings Pilot Completed Testing The froth production tailings pilot focused on validating the design assumptions for the following: TT deposition and consolidation columns cyclone FFT treatment (including chemical additions) using the following equipment: thickener centrifuge in-line mixing Planned Testing Planned froth production tailings pilot testing includes continuing pilot testing with specific test parameters. TOTAL E&P Joslyn Ltd. February 2010 Page 5-19

20 AI Project Update Froth Treatment Pilot Completed Testing The froth treatment pilot focused on refining design criteria for froth settler performance and tailings SRU performance. This pilot also generated feedstock for the froth treatment tailings pilot. Planned Testing No further froth treatment pilot testing is currently planned Froth Treatment Tailings Pilot Completed Testing The froth treatment tailings validated design assumptions for the following: froth treatment tailings processing and opportunities, including: asphaltene separation with cyclones hot water recovery with a thickener or centrifuge using flocculants alternative uses for asphaltene froth treatment tailings deposition (flume runs above and below water) consolidation column tests to understand deposition characteristics Planned Testing Planned froth treatment tailings pilot testing includes additional deposition and consolidation testing. 5.6 Plant Location and Layout The location of the extraction plant was selected to allow for adequate tailings disposal area on the west side of the CNRL road. The extraction plant site will be located east of the CNRL road, in the southwest corner of the mine pit and will occupy an area measuring approximately 285 ha (see Figure 5.6-1). Resource data indicate that no economic ore exists beneath the proposed extraction plant site. The plant site will contain the following: ore processing facility froth production froth treatment froth treatment expansion tailings production recycle water pond centrifuge plant utilities and cogeneration facility water treatment plant mine maintenance and administration building and control room tank farm For alternative extraction plant site locations assessed, and the rationale for selecting the proposed location, see Section February 2010 Page 5-20 TOTAL E&P Joslyn Ltd.

21 AI Project Update Figure Extraction Plant Site Layout TOTAL E&P Joslyn Ltd. February 2010 Page 5-21

22 AI Project Update February 2010 Page 5-22 TOTAL E&P Joslyn Ltd.