Project No.: 0317.02.038.040 Page 1 of 2

Project Name: Unconventional Oil and Gas CBI?

Yes

No

TELEPHONE CALL RECORD

Incoming

Outgoing

Date: 08/19/2015

09/03/2015

Time: 12:00

2:00

am

pm

Company Name: Terra Agua ERG Staff Name: James K. O’Connell

Contact Name: Dean Todd Contact Phone Number: 214-620-4415

General Subject: Discussion of Terra Agua’s treatment technology

TOPICS DISCUSSED AND ACTION TAKEN

08/19/2015 Call Participants

Dean Todd, Terra Agua

Pat Adams, Terra Agua

Kay Goss, GC Barnes Group (policy consultant for Terra 

Agua)

Lisa Biddle, EPA

Jesse Pritts, EPA

Debra Falatko, ERG

James K. O’Connell, ERG

09/03/2015 Call Participants

Dean Todd, Terra Agua

Pat Adams, Terra Agua

Michael Mitton, Mitton Technology

Lisa Biddle, EPA

Jesse Pritts, EPA

Debra Falatko, ERG

Brent Ruminski, ERG

James K. O’Connell, ERG

Notes

Introduction

Terra Agua initially contacted Bill Bates at EPA OGWDW, who referred them to Lisa Biddle. 

Lisa and Jesse began the calls by providing background on the UOG Rulemaking and CWT Study.

Dean Todd and Pat Adams have been working on a patented Canadian technology, Mitton Cavitation Reactor. Their company is 

called ETA Holdings, and they have exclusive rights for the technology for use in the food and beverage and oil and gas industries in 

North America.

Cavitation Process

The Mitton Cavitation Reactor is a reactor that uses two forms of cavitation to kill bacteria and precipitate scaling compounds. The 

reactor is a high speed valve, originally developed for use in automotive racing and modified for other cavitation applications such as 

wastewater treatment. The reactor contains a chamber with a rotating shaft to create hydrodynamic cavitation, and a resonator tube 

with harmonic frequency to create acoustic cavitation. Cavitation is the creation of small bubbles/cavities caused by a rapid change in 

pressure. The collapse of these bubbles releases energy, breaking bonds and destabilizing pollutants in the wastewater. 

Although the Mitton Cavitation Reactor does not use chemicals, it does include ports that can be used to inject chemicals, if desired 

(e.g., oxidants and pH adjustment). This capability can assist in treating specific constituents that may be present in a particular 

wastewater stream. For example, when treating oil and gas wastewater from the Permian Basin, injecting compressed air improved 

subsequent solids and oil/grease separation steps. Injecting compressed air also oxidized hydrogen sulfide to hydrogen sulfate. 

However, injecting compressed air was not effective in oxidizing other oxygen-demanding wastewater constituents such as 

biochemical oxygen demand.

The all-in cost to the operator is between 12 and 15 cents per barrel of effluent. Most operators do not believe such a low cost is 

possible, so Terra Agua typically presents the cost as “definitely under 25 cents per barrel.” Terra Agua has designed this process for 

multiple size reactors. The sizes include capacities of 5 gal/min, 350 gal/min, 550 gal/min and 700 gal/min. 1,300 and 2,500 gal/min 

units are currently being developed. The energy requirement is 1 kilowatt hour (kWh) per 24 barrels of effluent at an energy cost of 

about 1 cent per barrel. The technology has Patent Pending status in the U.S.

Cavitation Pilot Project

Terra Agua had a test site in West Texas which operated at 150 gallons per minute. The wastewater in their test was flowback and 

produced water from oil and gas wells in the Permian Basin Shale Region.
The goal was to treat produced water from mostly vertical, conventional wells to a clarified state for reuse/recycle in subsequent 

fracturing jobs. The pilot system included the cavitation reactor and pre- and post-separatory processes operated before and after the 

cavitation reactor. The pre-separatory process is a “pressurized weir” (pressure filter/pressure screen) to remove large solids from the 

waste stream. The post-separatory process is a 3-phase separator with oils coming off the top, treated wastewater from the center, and 

solids (including precipitated metals) coming off the bottom. There is typically 5-30 minutes of separation time after cavitation.

Terra Agua conducted about 3 months of testing during this pilot project. Towards the end of their test period, they experimented with 

the addition of hydrogen peroxide and caustic in the reactor. This test yielded good results for bacteria kill and improved solids 

separation.

At the test site, the average concentration of total suspended solids (TSS) in the influent produced water was around 350,000 ppm. 

After passing through the pre-separatory process and the cavitation reactor, the concentration of TSS in the effluent was 17,000 ppm. 

The goal of the entire system (pre-separatory process and cavitation, and post-separatory process) is to achieve 10,000 ppm of TSS. 

Their test results vary significantly when examining Total Dissolved Solids (TDS). 

Lisa Biddle asked, “Does the cavitation reactor remove TDS?”

It may be possible to remove TDS, provided the addition of a binding agent that would react with dissolved constituents and allow 

them to be removed in solids separation. For example, tests have shown 77% removal of sodium chlorine with the addition of zinc as a 

binding agent to generate crystallized zinc chloride that is removed in solids separation. TDS components that do not have an

appropriate binding agent (i.e., a compound that provides a “friendlier bond”) cannot be removed using this technology and will 

remain in solution. Additional tertiary treatment would be required to remove these constituents.

Spray Evaporation Process

Terra Aqua also holds a license for second technology which is a spray evaporation process. Terra Agua described that the 

evaporation technology includes a pit (180 feet in diameter) with a berm/fence to regulate wind. The pit is designed in a corkscrew 

with 6 to 10 industrial spray evaporators in the center. The evaporators use micron-sized spray nozzles to optimize evaporation. The 

technology is affected by the climate, specifically humidity (more than temperature). For example, the technology is not as efficient or 

effective in areas with high humidity. 

Terra Agua is trying to design an automated process for collecting the salt from the bottom of the pit. This will result in three possible 

resale and/or waste stream products from the evaporation technology:

 Clarified brine 

 Heavy brine reused for drilling

 Salts for resale

Terra Agua’s goal is to be able to achieve 100 percent recycling, so that the wastewater does not need to be disposed of (e.g., 

underground injection) or discharged (e.g., centralized waste treatment facility). The system goals are for water to be reused as 

needed, or used in creating other byproducts. From there, water can be evaporated into the hydrologic cycle, allowing the remaining 

mineral byproducts to be harvested.

The evaporation technology underwent a pilot test by the licensor in the Barnet Shale Region. They tested a small area with 2 

evaporators within a rectangle pit design. Terra Agua’s engineering partners point to a more efficient design using multiple 

evaporators with a circular design.

Terra Agua agreed to send white papers/public information for their technologies to EPA and ERG for review, as well as performance 

data for TSS, TDS and oil and grease.

Next Steps

EPA asked one final question, “What are your near-term plans?”

Terra Agua is moving into “Phase 3,” which includes 16 different pilot programs slated for food and beverage and oil and gas wastes. 

Specific to oil and gas waste treatment, they are planning to build a centralized facility in the Eagle Ford formation for full-scale 

treatment. They hope this will be commercially viable for produced water treatment within 3 to 6 months (most likely 5 months). They 

are considering completing another pilot test in Oklahoma (i.e., moving their West Texas system to Oklahoma). This may allow EPA 

the opportunity for a site visit sooner than the full-scale facility in the Eagle Ford formation.