## An Integrated Framework for Treatment and Management of Produced Water ! 

### Task 3 - Assessment of Management Options

• Explored through cost/benefit analyses the multiple conditions that have to be fulfilled in order to establish beneficial use from a technical, regulatory, political, environmental, economic, and legal standpoint: Beneficial Use Screening Module (BSM)

• Developed a structured decision process that identifies, evaluates, and (where possible) quantifies benefits, risks, and costs of each management option: Beneficial Use Economic Module (BEM)

# Integrated Framework Screening Tools

# Water Quality Module (WQM)
! 

### Objectives " Establish CBM produced water quality database " Basins, formations, wells " Output comprehensive constituent list for the Treatment Selection Module " Format into ExcelTM based macro enabled workbook " Downloadable from the RPSEA project website

# Water Quality Module (WQM)

# Water Quality Module (WQM)

# Treatment Selection Module (TSM)

# TSM: Development Challenges
! 

### Very large number of permutations " 32 treatment processes " 46 water quality parameters " Intelligent process selection
# 

### On-the-fly data trimming ! 

### Data, Selection Criteria, Validation " Treatment Technology Assessment Document " Input from academia & industry " Beta testing 8 corners, 12 edges > 3 billion combinationsTDS: 11,400 ppm TSS: 110 ppm Main Constituents: Na + , Cl - , Ca 2+ , SO 4 2- , HCO 3 - Micro-constituents: H 3 BO 3 , Fe 2+ , Al, As, Br, Cr, Cu, CN, F, Mg 2+ , Hg, K + Quantity: 0.4 MGD 

# TSM – Example from San Juan Basin

CBM PW Quality/Quantity

Desalination Selection o Energy: 8 kWh/kgal o Chemical demand
• Na 4 EDTA o Product water
• 85% water recovery
• TDS: 230ppm o Brine TDS: 67,000ppm Pretreatment Selection o Energy: 0.7 kWh/kgal o Chemical demand
• H 2 SO 4 , Na 4 EDTA o Product water
• Hardness removed by IX
• TSS removed by MF Beneficial Use Need to Treat? Desalination Selection

Suggested Pretreatment
• Microfiltration
• Ultrafiltration
• Media Filtration
• Ion Exchange
• Chemical Softening Pretreatment Selection

Post Treatment Suggestions Post Treatment/ Brine o Deep well injection Suggest Desalination
• Reverse Osmosis
• Membrane Distillation
• Vapor Compression
• Electrodialysis 

### ! ! ! Assess Technologies

capabilities

and site conditions Assess Technologies

capabilities

and site conditions Require Desal ?

# Beneficial Use Screening Module (BSM)

# Outputs ! 

### Qualitative weighted assessment of screening criteria

Example for illustrative purposes only

# Beneficial Use Economic Module

### Beneficial Use Economic Module

(BEM) 

# Beneficial Use Economic Module (BEM) Outputs: ! 

### Engineer’s planning level estimate of probable costs for selected BU ! 

### Summary of range of potential costs and values for selected BU ! 

### Comparison of multiple BU project scenarios or variation of one BU project Inputs: ! 

### Select BU ! 

### Project life ! 

### Long-term interest rate ! 

### Project details (conveyance, terrain, location, energy type, storage, other infrastructure) ! 

### Current disposal details ! 

### User unit costs (if available)

# Project Website http://aqwatec.mines.edu/produced_water

# An Integrated Framework for Treatment and Management of Produced Water ! 

### Task 4 - Field Validation of Viable Treatment Processes for CBM Produced Water

" Bench/pilot-scale treatment trains were designed, constructed, and tested at representative production site for field-scale validation " Data is being analyzed to determine the effectiveness, robustness, and ease of operation of treatment strategies " Testing results will provide validation of the integrated decision making framework

# Case Studies ! 

### Two Case Studies were analyzed " Powder River Basin " San Juan Basin ! 

### Components investigated " Water Quality Module " Treatment Selection Module " Beneficial Use Selection Module " Beneficial Use Economic Module

# Shortcomings of the First Generation Tool
! 

### CBM produced water only ! 

### Low resolution of Expert Ranking matrix ! 

### User input does not provide enough flexibility " Treatment technologies " Decentralization " Tailored water (system capable of producing water of different quality by changing operating conditions) ! 

### Economic/Energy " Low resolution " Cost/benefit not optimized " Resource recovery not incorporated ! 

### Environmental and social costs/benefits not optimized

# Decision Support Tool (DST) for Characterization, Treatment, and Beneficial Use of Unconventional Gas Frac Flowback and Produced Water

Prof. Mengistu Geza Prof. Pei Xu Prof. Tzahi Cath 

# Phase 2

# New Features of the 2 nd 

# Generation DST
! 

### Enhanced database for both CBM and Shale Gas " Quality, quantity, and distribution " Fracturing flowback water " Produced water " Potentially drilling muds ! 

### Technologies " Add more treatment technologies, including for energy, resource recovery, and residual management " Enable user-defined technologies " Increase resolution of all process parameters (Expert Ranking)

# New Features of the 2 nd 

# Generation DST
! 

### Add decentralization capabilities " Well head treatment " Well cluster treatment " Basin treatment ! 

### Tailored water (quality) " Improvement of beneficial use module " Define range of water quality for specific treatment trains ! 

### Improve optimization techniques

# Summary and Concluding Remarks ! 

### CSM will continue the development of the DST for a wider range of waste streams ! 

### The first generation DST successfully simulated logical treatment trains and cost/benefits ! 

### Second generation DST will have higher resolution and stronger capabilities dealing with different feed streams, beneficial reuse, and resource recovery " More robust Expert Ranking matrix " Improved User Ranking module " More robust Economic Module that takes into consideration costs and benefits (economic, social, environmental, ecological) " Ability to optimize several treatment plants within a basin

# New Treatment Technologies

# Technology Requirements ! 

### Robustness, flexibility (quantity/quality), modularity ! 

### Desalination " Many of the desalination technologies are well established " Minimal effort to adapt in the field, but need PRETREATMENT ! 

### Integrated membrane systems provide many benefits " Selective removal of contaminants by size " Selective removal of contaminants by chemistry " Can be relatively easily tailored/hybridized with other physical, or chemical, or biological processes " Easily scalable " Yes, they have limitations ! so more R&D is needed !

# The Future of Membrane Processes in O&G E&P

! 

### Current commercial membrane processes have some limitations: " Fouling/scaling " Limited pressure (at high salinity) " High energy (myth?) " But they are still, and will be the workhorse ! ! 

### Membrane processes that might benefit the O&G industry:

" Ceramic membranes
# 

### Microfiltration and ultrafiltration
# 

### Nanofiltration " Engineered Osmosis " Membrane Distillation " Biological processes (MBRs)

# RO a Strong Technology

! But Has Notable LimitationsEnergy, kWh/m3

1% 2% 3% 4% 5% 6 8 10

% Total Dissolved Solids 4 High Efficiency RO (HERO) Operating pressure upper limit ~80 bar (~1,200 psig)

2 NF BWRO & LPRO SWRO

8% 

### True if feed water is of good quality
• TSS?
• Low solubility salts?
• Algae?
• Boron? 0
Source: GWI, vol. 13 (1), 2012

# Osmotically Driven Membrane Processes

! P= !"
Brine Feed 

### Osmotic Dilution or Concentration 

### Selective Mixing

Cath, Hancock, et al. 2009

Image: Hydration Technology Innovations

# Forward Osmosis – Reverse Osmosis Desalination

! 

### NaCl draw solution ! 

### Constant concentration ! 

### No pretreatment required ! 

### New generation Limited by RO reconcentration

Forward Osmosis (FO) “ engineered osmosis ” RO Brine Reconcentration Draw Solution Feed

# Forward Osmosis Advantages Treating Tough Waste Streams !

# Oil & Gas Exploration and Production

Grit/Solids

Removal Oil Separation Coagulation/ Flocculation/ Sedimentati on Biological Treatment Air Stripping

Advanced Oxidation Filtration (MF, UF) Reuse Options

Sludge Pits FO Membranes RO

# Oil & Gas Exploration and Production

Reuse Options

Sludge Pits FO Membranes RO Membranes

# Oil & Gas Exploration and Production

Grit/Solids

Removal Oil Separation Coagulation/ Flocculation/ Sedimentati on Biological Treatment Air Stripping

Advanced Oxidation Filtration (MF, UF) Reuse Options

Sludge Pits FO Membranes RO

# Oil & Gas Exploration and Production

http://www.emeraldsurf.net/forward-osmosis-the-green-machine/

# Oil & Gas Exploration and Production Haynesville Basin – HTI Green Machine ! Trailer mounted FO pressure vessels ! 24x 8” spiral wound FO elements ! Draw solution " ~6% NaCl initial concentration " ~4.6% NaCl final concentration ! RO reconcentration system " 16x 8” spiral wound RO elements ! ~85% water recovery ! Minimized membrane fouling/ cleaning Operating Condition Feed and draw solution flow via pumping (~60 psi hydraulic TMP)

# Oil & Gas Exploration and Production Haynesville Basin – HTI Green Machine

!" #!!!" $!!!!" $#!!!" %!!!!" %#!!!" &!!!!" &#!!!"

!" #!" $!!" $#!"!"#$%&'()*##"+,(

-.%&'(/"$0,( '()"*+)(,"-(./0(12"3+4" 5,+6"7+89":/42"3+4"

!" $" %" &" ;" #" <" =" >"

!" #!" $!!" $#!"1*2&0(3#$4'(5(%67(8069((

-.%&'(/"$0,( 5?"@0(,+3("54AB2"CDE" ~18% Decline

Initial Feed Conductivity: ~6.8 mS/cm Final Feed Conductivity: ~32.5 mS/cm Achieves 85% recovery and 5x concentration of WW

# Demonstration Projects – Produced Water

> 1,200 hours of operation > 400,000 liters of water treated

### @0(,+3("*+)(,"-(6/0(,FG"<!H" 0 1,000 100,000 150,000 200,000 250,000 300,000

Feed Brine ProductConcentration, ppm

0 1,000 2,000 3,000 4,000 5,000 6,000Product Concentration, ppm Not to Exceed 10# Brine Brine Goal 

# Permian Case Study Data

# Marcellus Case Study ( Raw | Product | Brine) 

### ! ! !

! ! ! ! Avg. Water Recovery: 65%0.010.1

# Dealing With the Hypersaline Brines !

# Membrane Distillation ! 

### Heated aqueous feed solution is brought into contact with the feed side of hydrophobic, microporous membrane ! 

### The hydrophobic nature of the membrane prevents penetration of aqueous solution into the pores ! 

### cold fresh water is in contact with the permeate side of the membrane ! 

### vapors diffuse through the pores and directly condense into the cold stream adapted from: http://www.water-technology.net/

# Water and Minerals

High-quality water Engineere d System

Impaired water 

## Water & Mineral Supply

Fertilizers Road Salts

# :+.;*#(<="+"%.=(<>*#$*;"+( ! 

### We have managed to successfully concentrated GSL water from 150K ppm TDS to >300K ppm TDS!!!
! 

### Natural evaporation " 2 ft / yr = 1.64 mm/day " 3 years for recovery of minerals (!) ! 

### Membrane distillation flux " 12 L/m 2 

### /hr = 288 mm/day " ~ 175 times faster " ~ 1 week instead of 3 years !

# Comparing Natural Evaporation for Mineral Recovery to MD and FO

8” ~400 ft 2 of membrane 

### 40” Natural Evaporation Membrane Distillation Forward Osmosis Water flux 0.6 m/ yr 12 L/m 2 -hr 3 L/m 2 -hr Water flux, mm/d 1.644 288 (175x NE) 72 (44x NE) Time 1,100 days 6.5 days 25 days Foot print 1 acre (43,560 ft 2 ) 250 ft 2 990 ft 2

# Acknowledgement ! 

### My students and postdocs at CSM ! 

### Hydration Technology Innovations and Oasys Water ! 

### NSF/SRN ! 

### DOE/RPSEATzahi Cath, Ph.D. Associate Professor and AQWATEC Director Department of Civil and Environmental Engineering Colorado School of Mines Golden, Colorado 80401-1887 Phone. (303) 273-3402 Email. tcath@mines.edu 

# Thank You