Showing posts with label desalination. Show all posts
Showing posts with label desalination. Show all posts

Monday, April 08, 2013

Interview with Patrick Horner, Fountain Quail / Aqua-Pure: Innovators in Technology Series


In the quest to put the puzzle pieces together to help convert the saltwater (brine) that is coproduced with gas and oil into a usable product, and help solve the problem of water shortages, polluted surface and ground water, and and a host of other issues, we are featuring interviews and technology profiles that relate to questions raised by our earlier post, Getting Started in Purifying Produced Saltwater, the Overlooked Resource in Resource Plays.

When visualizing how produced water could be purified and used in useful applications, a number of questions come to mind. I've listed a few of the ones that immediately occurred to me, and I asked Patrick Horner of Aqua-Pure (Fountain Quail in the U.S.), to respond to a few questions.  Thank you, Patrick, for responding.

1.  How easy is it to get started distilling water from a well that is making 100 bbls of fluid a day, with 5% oil cut and 50 mcf gas?

Typically, on-site distillation systems for volumes of 100 bb/day are not practical from a cost/logistical perspective.  We would recommend a water management system (either pipeline collection system or truck pick-up) that brings water to a central facility capable of processing 4000 bbl/day.  A separator could be used at the well to separate gas and/or oil.  Oil could be kept with the water and separated at the central facility to minimize equipment at the well (gas/liquid separation equipment would be required at the well prior to transportation of the water).

2.  Do you have to let the water settle longer? Do you recommend using surfactants to separate the water and oil more quickly?

This is very much a function of the nature of the oil (API density etc and degree of emulsification).  The oil water separator can be designed accordingly (surfactants may assist in the separation process, again usually depending on the degree of emulsification).  There are many effective de-oiling technologies available but again these can range from simple tank systems (gun barrel type) to hydro cyclone type separators depending on the amount and type of oil.

3.  Can you use the produced gas as energy for the distillation / condensation process?

Yes, we currently use produced gas in our NOMADS to power the process.  Some level of gas treatment many be required depending on the quality of the gas.  Typically, for raw gas, this involves a coalescing type filter to remove any liquids and/or solids.  If H2S is present, this would need to be scrubbed out.

4.  How pure is the end product?  Is it potable? 

We have designed our systems to meet EPA NPDES discharge permit requirements (not potable water specifications).

5.  Does distillation remove aromatic HC?

Distillation does not remove aromatic HC.  Anything more volatile than water will carryover with the distillate (and MVR Evaporation).  There are ways to ensure aromatic HC is not present in the distillate.  This would include reducing aromatic HC prior to the evaporator (via oxidation and/or stripping) and polishing the distillate if required (oxidation and an adsorption bed such as activated carbon to polish).  Biological methods can be used to remove organics from the distillate as well but this requires the addition of nutrients which may in the end reduce the overall water quality.

6.  Do you get EPA Drinking Water approval at the wellsite, or should we take the water elsewhere for further processing / testing?

Again, a NPDES discharge permit is a realistic goal for this type of water treatment.  We haven’t  evaluated EPA Drinking Water approval. Any level of treatment is possible, it’s just a matter of what is feasible from a cost perspective.  By meeting the NPDES requirements, I expect we are close to drinking water standards but the level of oversight/monitoring/testing/QC would likely be a step up for EPA drinking water standards.  This may not be practical at small volume facilities.  I expect that if the treatment facility meets EPA NPDES, the water could be transported to a drinking water treatment facility for further processing to meet EPA Drinking Water Approval.

In North America, there is big perception issue with where the water comes from.  Singapore has a facility that recycles municipal sewage into drinking water (at a quality higher than we typically see in North America), even though they are meeting the requirements, the optics of where the water came from would be an issue in NA.  I expect the same would be the same for turning oilfield produced water into drinking water.  I’m not aware of any scenario where oilfield produced water is being turned into drinking water in North America I am aware of a few projects in Australia that are doing this but again (recharge drinking water aquifers with treated produced water), the culture is different.  I’m curious if you know more about this.

(Susan's response:  No, the only ones I can think of that might be similar are in Wyoming, where "fresh" water coproduced from coalbed methane is used to recharge surface impoundments (which would eventually recharge groundwater, and a few possible areas in Texas where produced water is used in lined stock tanks for personal use on private property.) 

Saturday, March 30, 2013

Getting Started in Purifying Produced Saltwater, the Overlooked Resource in Resource Plays

A solution to drought and water scarcity is sitting before our eyes in much of the U.S., but most people have no idea that it exists. Those who do have no idea that the puzzle pieces necessary to make it happen are right here, right now. They just have not been put together yet.  But, they can be, and the benefits to people, the environment, the economy, and sustainable life in general could be staggering.

The answer is produced saltwater which is coproduced with oil and gas, as well as in mining operations.

Many people outside the oil and gas industry are unaware that great volumes of salty, briny, mineral-rich (although some are undesirable minerals) water are coproduced with gas and oil. In fact, in many old fields, the percentage of water vs. oil and gas is very high, and can be as high as 1000 barrels (40 gallons) of produced water for every 100 mcf (thousand cubic feet) of natural gas and 10 barrels of oil.  The water is sometimes reinjected into the formation to provide pressure to enhance the recovery of hydrocarbons, but most often, the oil and gas are separated, and then the saltwater is trucked or transported via pipeline to injection wells that are licensed as Class II disposal wells. These wells may take as much as 20,000 bbls per day. Not only are they expensive to use and to operate (lots of chemicals are needed and equipment to deal with all the corrosion, scale, and other issues), they have also been blamed for generating earthquakes. Needless to say, safety and public health are the first concerns, so any solution will require a great deal of testing and quality assurance. 

Large sources of coproduced water include traditional mature fields such as the Permian Basin and in the Sooner Trend (Mississippian lime), but also in the new unconventional plays, such as in the Mississippian Lime (and chat) in Kansas and Oklahoma and in the shale plays throughout the world, with extreme development now taking place in the U.S.  For a compilation of articles on the plays, please visit: (http://www.searchanddiscovery.com/documents/2013/70135nash/ndx_nash.pdf).

Disposing of produced saltwater is expensive and an ongoing cost to producers. There is no escaping it. For that reason, the small extra steps required to purify rather than dispose of the water represent an incremental cost, which could be more than offset by the revenues generated by water sales. There are other benefits, but educating the public will be necessary. For that reason, companies and communities along with entrepreneurs who are a part of the team, should start as quickly as possible to develop MOOCs (massive open online courses) and mini-MOOCs to help people learn about the concept, the elements, the skills needed, and the opportunities.

Further, the need by some communities for water, and the market for water could make producing and purifying co-produced saltwater viable on its own.

Desalination of seawater and brines has long been a necessity in arid parts of the world, where drinking water is scarce or unavailable. It is generally viewed as uneconomic or too capital-intensive for many communities in the U.S.

Purification of produced coproduced water is not completely the same as desalinization of sea water because there are additional minerals in the produced water (the reservoir fluids each reservoir have unique compositions), and it is not cheap. However, companies that are now paying to transport, chemically treat, and inject produced brines would not pay much more to take the extra step and purify to graywater or potable levels. 

With drought, coupled with the depletion of aquifers in the Plains and western U.S., new approaches to water must be sought. The plan to purify produced saltwater to the point of graywater or agricultural use or all the way to potable is economically viable for some communities right now if the pieces are put into place.

Here are the puzzle pieces:

Large-scale produced water purification systems:

Effective and efficient purification process.

Options include

Reverse osmosis / membrane ultrafiltration (primarily with dry gas production)

Distillation (will require using produced gas, solar, and possible geothermal to minimize energy costs -- Fountain Quail has a freshwater system called NOMAD which is currently in the Barnett (in Texas) and also is setting up in West Texas, in the Permian Wolfcamp play.  Their mobile ROVER system creates clean saltwater.)

 Combination process (primarily with reservoirs that produce oil as well as gas - Hydrozonix is currently using its multi-stage process to treat and remove contaminants in order to recycle and reuse the water in drilling, stimulation, or enhanced oil recovery).

Water gathering system (similar to that of gas gathering systems) to cost-effectively bring the produced water from several wells or units to a single, high-volume treatment facility, with capacity of around 100,000 bbls per day. Companies such as Anterra Energy and Apache / Encana (Debolt water treatment plant) are running water treatment operations that are allowing companies to use the water for recycling and for hydraulic fracturing and injection wells in EOR operations. There are initiatives to support this, which include the Texas Water Recycling Association (TWRA).  One of the positive developments is that the TWRA members will be able to share recycling facilities. 

For recharge of the riparian system where the water will go to reservoirs and other holding water impoundments for agricultural purposes, it will be necessary to construct series of viaducts into the stream system so that the produced water will flow to existing reservoirs. Discharge could average 100,00 bbls per day. The viaducts could incorporate small, efficient hydroelectric generators so that power could be generated as the water flows downstream. 

Contracts and agreements with the communities to purchase the water and to also commit to financing the infrastructure (they may wish to finance it via municipal bonds).

Amended and modified oil and gas leases would be developed to pay the mineral owner a royalty on sales of coproduced connate water. Because the costs of purification and transportation are high, and the royalty would of necessity be something in the 2 – 3 percent range.

A plan for disposing of the super-concentrated brines that are left after the process must be in place.

On-site continuous water quality testing, with remote data acquisition and monitoring, with cloud-based data acquisition, archiving, processing, retrieval.

Initial data sources for identifying, leasing, purchasing existing production and adapting into the new produced water / water purification systems.

Byproducts could sold as industrial minerals or created into new products.

 Examples:
Halite building bricks: coat the salt residual with impermeable coating, and create salt bricks for building purposes (could be used to create soundproofing, etc.)

--Industrial minerals: halite, ferric chloride, magnesium oxide, calcium chloride

--Data management system for maintaining production records, along with water quality

--MOOCs (massive open online courses) and mini-MOOCs to help people learn about the concept, the elements, the skills needed, and the opportunities

--Data management system for leases, contracts, permits, filings, reports; much should be automated with calendar events to flag and alert due dates for key filings and permits

--Cloud-based computing for logistics, data management, tracking, quality assurance, supply chain management

For small-scale systems for single wells, that produce less than 1,000 bbls of water per day:

--Mobile purification units, ideally distillation
 
--Permits and permissions for drinking water production and bottling facility

--Licensed and approved continuous testing of water

--On-site or near-site bottling of water

--3D printers for customized bottles / shapes for value-add uses

--Advertising / marketing of new ultra-pure water from distillation

--Contracts for distribution

--MOOCs (massive open online courses) and mini-MOOCs to help people learn about the concept, the elements, the skills needed, and the opportunities

--Cloud-based computing for logistics, data management, tracking, quality assurance, supply chain management

Conclusion and Future Steps

The main impediments to purifying and re-using connate water coproduced with oil and gas involve cost, environmental and drinking water regulations, and public perception.

These can be overcome with education coupled with extreme need due to drought. The benefits are tremendous, and include revitalized communities with sufficient water for sustainable human and animal life, along with the resurgence of industries requiring large volumes of water, which include agriculture, power generation, and manufacturing.

The key now is to start to put the puzzle pieces together and to start to create viable projects and plans.

We need to conduct clear-eyed, open, and honest gap analyses to see just how close we really are, and where and when we can most feasibly close the gaps.

The efforts can start on a well-by-well micro scale, thanks to 3D printing, cloud-based computing (for logistics, data management, supply chain, project management, etc.), so is ideal for entrepreneurs. 

For more information and initial plans, please contact Susan Nash as susan@beyondutopia.com 

-- Susan Smith Nash, Ph.D.
Norman, Oklahoma
susan@beyondutopia.com 
@beyondutopia
skype: beyondutopia 

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