# DETERMINING THE MINIMUM TREATMENT LEVELS REQUIRED FOR PRODUCTION EFFICIENCY: STATING 

# THE LOWEST ACCEPTABLE WATER QUALITY LEVELS FOR EFFECTIVE REUSE IN FRACS NOVEMBER 19TH 

## 2014

###  

# Operational Logistics  

# Field Specific Parameters  

# Produced Water Quality  

# Treatment Trials  

# Path Forward A JOURNEY IN WATER RECYCLE

###  

# Economy of Scale  

# Available non
-fresh water  

# Transportation logistics  

# Processing capacity  

# Effective treatment 

# WATER REUSE: KEYS TO SUCCESS 

## Completions: Active frac program w/ 85K

– 185K Bbls/well  

## Availability: ~15K 

## Bbls/day  

## Logistics: Move from trucking to pipeline  

## Processing: 240,000 Bbls  

## Treatment: 250 - 400 gpm  

## Reused ~ 1.9 Million Bbls to date 

# WHEELER COUNTY WATER LOGISTICS

## Basic Frac Water Criterion: 1) 

# Water must be compatible with completion fluid design. 2) 

# Water must not be damaging to well production 

# (IP & EUR). 

# WATER QUALITY AND TREATMENT

5 

### Simple Treatment Design:  

### Iron and Iron Sulfide  

### Suspended Solids  

### Bacteria  

### Mitigate Scale Potential 

# WHEELER CO PRODUCED WATER CHEMISTRY PW Component (PPM) Average Rough Guideline for Upper Limit: PH 7.2 Between 6-9 Calcium 800 2,000 Bacteria: APB & SRB >10 6 10 2 Chloride 15,000 120,000 Alkalinity 723 800 Barium and Sulfates 4 25 Ferrous Iron 1 10 Total Iron 18 25 Boron 17 20 for XL; NA for SW TSS 245 100

## Batch Treatment in Processing Tanks:  

## Treat 20K – 30K bbls at a time in a tank  

## Various treatment options utilized  

## Waste generation skimmed off, or settled to bottom  

## Relatively low cost, $0.15

-$0.40/bbl  

## Operationally challenging with mixed results 

# LEARNING WHILE IN MOTION

## Utilizing automation to generate Chlorine Dioxide for produced water treatment :  

## 99.999% Reduction in Bacteria  

## 88% Reduction in Oil and Grease  

## 70% Reduction in Iron  

## 5 5% reduction in Suspended Solids 

# UPFRONT WATER TREATMENT CLO2, WEIR TANKS, FILTERS

# UPFRONT WATER TREATMENT CLO2, WEIR TANKS, FILTERS

# Centrifuge trialed both before and after ClO2:  

# 40% Reduction in TSS  

# Oil/Water emulsions impact performance  

# Will not remove particles <6 microns 

# UPFRONT WATER TREATMENT CLO2, WEIR TANKS, CENTRIFUGE

# UPFRONT WATER TREATMENT CLO2, WEIR TANKS, CENTRIFUGE

## Utilizing ClO2 and chemical p recipitation through a clarifier:  

## 99.999% Reduction in Bacteria  

## 99% Reduction in Oil and Grease  

## 99% Reduction in Iron  

## 92% reduction in Suspended Solids 

# UPFRONT WATER TREATMENT CLO2, WEIR TANKS, CHEMICAL PRECIPITATION

# UPFRONT WATER TREATMENT CLO2, WEIR TANKS, CHEMICAL PRECIPITATION

 

# Is the additional expense providing value?  

# How do we measure water treatment value?

# RESULTS AND COST: PW Component (PPM) Average Weir Output: Centrifuge Output: Clarifier

Output: PH 7.2 6.6 – 7.0 6.6 – 7.0 7.1 – 8.1 Calcium 800 700 – 1000 700 – 1000 400 – 475 Bacteria: APB & SRB >10 6 100 100 100 Chloride 15,000 14,000 – 17,000 14,000 – 17,000 14,000 - 17,000 Alkalinity 723 400 - 700 400 - 700 400 – 475 Barium and Sulfates 4 3 -4 3 -4 3 -4 Ferrous Iron 1 ND ND ND Total Iron 18 3 -5 3 -5 ND Boron 17 1 6 - 21 1 6 - 21 16-21 TSS 245 43 - 141 30 - 90 16 - 40 Cost: $0.20 – $1.00 $0.25 – $1.25 $0.75 – $1.75

# WATER TREATMENT OPTIMIZATION: WHAT TREATMENT IS NECESSARY?  

# Production comparisons are difficult due to large number of variables in well production :  

## Water treatment technique  

## Formation  

## Percentage of PW used  

## Completion design  

# IP’s on FW and PW wells appear similar  

# More data, and controlled comparisons are needed to draw trending conclusions on impact of production 

# from PW reuse.

# I MPACT TO THE 

# F RAC 

# : S LICKWATER 

# VS

# . G ELS

16 

### Raw Water: Unusable After ClO 2 

### : Stable FR After Clarifier: 

### Stable Gel

0 50 100 150 200 250

Untreated Weir Clarifier Tap Viscosity (cP) Crosslinked Viscosity, pH 8-9 @ 300 rpm

0.5 hr 4.5 hr

0 20 40 60 80 100

0 1 2 3 4 5 6 % FR

Time (min) ClO 2 & Clarified Water + 0.5 gpt FR

ClO2 Clarifier Tap Water 

### Batch treatment, ClO2 and Clarification all created a water q uality s ufficient for slickwater/linear jobs.  

### Friction reduction and gel hydration increased with water quality.  

### Calcium hydroxide precipitate at 

### high PH (pictured) in some water. Borate XL jobs require further water treatment.  

### Treated water was compatible 

### with low PH and cellulose type XL fluid systems. 

# WHEELER COUNTY WATER LOGISTICS 

## Bacteria Growth in storage tanks is challenging in warm months.  

## Water treated to a higher standard (Clarifier) retained lower bacterial counts (less smell, higher transmittance) for weeks.  

## Holding processing tanks in a bio


## static environment for weeks in the summer is cost prohibitive  

## Treat bacteria for the frac, with an 

## on the fly system providing an economic high log kill  

## Understand and test bacteria kill 

## system design. Optimize for cost. 

# TREATMENT OBSERVATIONS

## Analysis of a 2
-8 well completion program showed 3X-5X cost increase for re
- use water compared to fresh water 

# MOBILE TREATMENT OPTIONS: WATER REUSE FOR SMALL SCALE OPERATIONS:

Water Treatment Tank in Tank Storage 

## The technology is available to reuse water.  

## Logistical challenges can be met.  

## Economics ultimately 

## t rump: Low cost acquisition/disposal of water create financial barriers to reuse.  

## Logistics, disposal, incentives, regulations and supply constraints will together shape the 

## future of water reuse in an economic manner. 

# WATER RE- USE WHERE DO WE GO FROM HERE?