Modeling Costs for Produced Water Reuse Scenarios

Transcription

1 New Mexico Produced Water Conference November 15-16, 2018 Modeling Costs for Produced Water Reuse Scenarios Pei Xu, PhD Associate Professor, Environmental Engineering New Mexico State University 1 Environmental Lab of Innovative Technologies

2 Integrated Decision Support Tool (i-dst) for Management of Flowback and Produced Water Characterization, Treatment and Beneficial Use Develop an i-dst capable of selecting produced water treatment options based on the composition of produced water and intended beneficial use with consideration of multiple factors, criteria, constraints and functions Identify cost-efficient and environmentally sound strategies for management and treatment of flowback and produced water Reuse versus disposal options Produced water Water Reuse 2

3 Outline Integrated Decision Support Tool (i-dst) Treatment Technologies Water Quality Database Approach for Treatment Selection Case study Permian Basin Summary 3

4 Produced Water Treatment Technologies 4 Requirements High rejection of contaminants: meet reuse requirements Low demand on energy and chemicals Minimize waste disposal Robustness and low-maintenance: reduce labor and supervision requirement Flexibility: able to handle high variation in water quality and quantity Modular: small footprint minimal environmental disturbance

5 Treatment Technology Assessment A total of 62 technologies were reviewed- included in DST An Integrated Framework for Treatment and Management of Produced Water TECHNICAL ASSESSMENT OF PRODUCED WATER TREATMENT TECHNOLOGIES 2 nd EDITION RPSEA Project Dr. Pei Xu, Guanyu Ma, Dr. Zachary Stoll New Mexico State University Department of Civil Engineering Las Cruces, NM pxu@nmsu.edu Phone: Dr. Mengistu Geza, Dr. Tzahi Cath, Dr. Jörg Drewes Colorado School of Mines Department of Civil and Environmental Engineering Golden, CO mgezanis@mines.edu; tcath@mines.edu; jdrewes@tum.de Phone: ; August 2016

6 Treatment Technologies and TDS Bins Produced Water Pre-treatment Treatment/Desalination Deep Well Injection Removal of: TSS Organics Hardness Waste Disposal TDS Bins (mg/l) < 10,000 10,000 40,000 40,000 70,000 > 70,000 Mature, less costly, existing technology - RO/NF - ED/EDR Mature, cost intensive, existing technology - SWRO - BWRO Moderate mature, moderate costly technology - MVC - MED Emerging, cost intensive technology - FO - MD 6 Beneficial Use Reuse for hydraulic fracturing (No desalination required) Reuse for other purposes (potable use, aquifer recharge, irrigation, industrial, etc.) Recovery of valuable products and energy (I 2, NaCl, NH 4 Cl, MgCl 2, Na 2 CO 3, etc.)

7 Water Quality Database by Basin A water quality database has been collected, summarized and built into the i-dst Basins (17) with produced water Colorado- 2 basins Ohio-1 basin New Mexico- 2 basins Oklahoma -3 basins New York-2 basins Texas-2 basins Pennsylvania-4 basins Wyoming- 1 basin Pennsylvania- Frac flow back water Basins (4) with Geothermal energy sources for desalination California- SaltonSea Texas -Hidalgo Nevada-Washoe Nevada-Steamboat The i-dst compares water quality from a basin to the water quality 7 requirements for a user selected beneficial use and selects treatment options

8 Treatment Selection Approach A very large number of permutations 62 treatment processes and 46 water quality parameters Complexity increases with number of treatment technologies, number of water quality parameters, and number of treatment/system constraints to be added Intelligent process selection 8 Multi-Objective Optimization (MOO) approaches - Algorithms based on a non-linear optimization with defined constraints and objective function

9 Overview of the i-dst 9 Water Quality Module Constituents Required TE A list of criteria Weights, expert ranking Selects the best treatment train with respect to technical & economic criteria while meeting water quality requirements. User & Expert Ranking Module Treatment Selection Module [Optimization module] Treatment train Cost Estimates, Energy demand Economic & Energy demand Module Treatment cost Energy requirement

10 Simplified User Interaction 10

11 User interaction Output viewing options 11

12 Case Study Permian Basin, New Mexico Lea County Eddy County 12

13 Produced Water Quality Average TDS 90,000 mg/l. Samples with lower TDS values (yellow circles) show clusters in eastern Lea County where there is also relatively high water production. 13

14 Combining GIS Mapping for Evaluating Beneficial Use Feasibility - Irrigation 14 Irrigation water TDS 1500 mg/l Eliminated wells with TDS over 40,000 mg/l 983 active oil and gas wells included in the cluster Annual produced water production: ~170 million bbls Average distance to irrigation areas: 1.9 miles Treatment: three-phase separator settling tank - chemical softening - media filtration - seawater RO - solid and liquid waste disposal.

15 Combining GIS Mapping for Evaluating Feasibility Surface Water Augmentation 15 Pecos River TDS 5,000 mg/l Produced water TDS ~ 35,000 mg/l 759 active oil and gas wells included in the cluster Annual produced water production: ~17 million bbls Average distance to Pecos River: 4.5 miles Treatment: three-phase separator settling tank - chemical softening - media filtration - electrodialysissolid and liquid waste disposal.

16 Combining GIS Mapping for Evaluating Beneficial Use Feasibility - Mining 16 Acceptable water quality is 100 g/l TDS Average PW quality 145 g/l Average distance to mining sites: 10 miles Produce clean brine with threephase separator - settling tank chemical softening/coag./floc./sed. - media filter - waste disposal. Blending with lower TDS water

17 Combining GIS Mapping for Evaluating Beneficial Use Feasibility - Fracturing 17 Hydraulic Fracturing System Cross Link Gel Slickwater ph > 5 Total Suspended Solids < 0.1 mg/l Microbes Require disinfection Hardness (Ca+Mg) < 2,000 mg/l - Iron < 20 mg/l - Sulfate 200-1,000 mg/l - Chloride < 40,000 mg/l - Bicarbonate < 1,000 mg/l - Boron < 10 mg/l - Multivalent Ions - < 5,000 mg/l TDS - < 40,000 mg/l Reducing Agent < 25 mg/l -

18 Combining GIS Mapping for Evaluating Beneficial Use Feasibility - Fracturing Cross-link gel system does not require TDS concentration, but limits hardness: three-phase separator - settling tank - chemical coagulation/flocculation/settling - media filtration disinfection Slickwater system requires desalination: three-phase separator - settling tank - chemical coagulation/flocculation/settling - media filtration disinfection SWRO at low recovery 18

19 Case Study Permian Basin Disposal Cost ($/day) Unit Cost* ($/kgal) Unit Treatment Cost ($/bbl)* Product Flow (bbl/day) Marginal benefits ($/day) Irrigation w/swro Crosslink Gel Slickwater w/ SWRO Slickwater w/ Blending Pecos River Augmentation Mining 18,000 18,000 18,000 18,000 18,000 18, ,000 18,000 9,000 18,000 9,000 18,000 4,158 13,213 6,327 13,215 4,986 9, The cost estimates are in the range of -30% to +50% for feasibility study. Unit costs including water treatment and distribution Benefits do not include the saving from use of freshwater

20 Summary and Concluding Remarks The i-dst provides an integrated produced water management tool that accounts for quantifiable and nonquantifiable criteria in the selection of treatment processes Offers additional flexibility considering factors, constraints and objectives in selecting the final treatment trains Simulates logical treatment trains for various source water types Provides a screening-level economic estimate for produced water treatment and reuse 20

21 21 Summary and Concluding Remarks Use of produced water for hydraulic fracturing is economically feasible, while agricultural irrigation and instream augmentation of Pecos River are expensive. The transportation cost to mining is estimated high. Investments on infrastructure of water treatment, storage, collection and distribution. Liability and users of treated water Public acceptance, water rights and regulations Environmental and social benefits should be included Innovative technologies for water quality characterization, treatment and resources recovery, in particular for brines Renewable energy driven, low costs treatment technologies (visit posters)

22 Acknowledgement 22 DOE/RPSEA (Research Partnership to Secure Energy for America) New Mexico Environmental Department Guanyu Ma at New Mexico State University Mengistu Geza, Tzahi Cath, Jorg Drewes at Colorado School of Mines Katharine Dahm and Katie Guerra at BoR Robert Sabie, Sam Fernald, Kenneth Carroll, Jeri Sullivan- Graham, Martha Cather Brent Van Dyke and Donnie Hill

23 Thank you! 23