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7/25/2019 Clear Well

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ClearWELL™

Scale Control

An innovative approach to controlling scale, maximizing

production ow rates and reducing your maintenance costs

Clearly superior technology



Proprietary, one-of-a-kind technology

Scale formation in naturally hard water can reduce the

production efciency of wells and shorten the life of

equipment—downhole and on the surface. Produced

water contains dissolved mineral ions, including

calcium, barium, strontium, carbonates and sulfates.

When these ions reach a point of supersaturationbecause of a sudden drop in pressure, changes in

temperature, a commingling of incompatible waters

or a change in pH or water chemistry, the mineral

salts become less soluble and deposit out as thick

scale. The scale adheres to pipe walls, downhole

pumps, surface owlines and the internals of surface

equipment—reducing production, jamming critical

isolation or safety valves and causing well instrumentlines to plug.

The problem

2 © 2009–2013 Weatherford. All rights reserved.



ClearWELLTM

Scale Control

ClearWELL scale-control technology—one of

Weatherford’s latest offerings in ultragreen technology

sets the pulse for peak production ow rates by

controlling scale buildup down the wellbore and

throughout surface-production equipment.

ClearWELL technology solves scale formation problems

by generating an electric eld down the wellbore and

through the surface owlines and equipment. This electric eld causes most of the scale to form as small particles

in the bulk uid owing from the well, instead of becoming

immobilized and depositing on the metal surfaces of the

well and surface equipment.

Patented ClearWELL technology is the only system

that creates a protective electric eld, induced and

transmitted throughout the entire piping network,

affecting the water droplets and ensuring full protection.

This one-of-a-kind innovation ghts scale buildup by

preventing it from depositing in the rst place.

As a result, the scale ows out of the system, without

restricting ow or operations. And because scale

deposition is so greatly minimized, it’s only natural that

your ow rates will go up, and your maintenance costs

will go down.

Better still, the easy-to-install ClearWELL unit ghts

scale with no pollution and zero intervention.

The solution

The system treats acid-insoluble hard scales

(like barium sulfate and strontium sulfate) and

acid-soluble soft scales ( like calcium carbonate)

with great success.

Top-to-bottom, 24/7 protection

ClearWELL technology treats the entire well system

24 hours a day, seven days a week. Not only does

this device protect against scale buildup on tubulars,

but it also extends the life of valuable downhole

pumps, valves and equipment by retarding fouling

that leads to premature failure.

The ClearWELL device is quickly tted at the surface

on the wellhead—an entirely noninvasive installation,

with no interruption of production.

3© 2009–2013 Weatherford. All rights reserved.



The benefts are clear

Weatherford’s ClearWELLTM

technology greatly minimizes systemwideproblems associated with scale, by treating the entire wellbore and

the owlines. No other technology can do this.

ClearWELL technology enhances safety by minimizing the need

for hazardous acids and hot oils, as well as the headaches of

chemical-pump maintenance, delivery logistics, winterized

injection systems and chemical-residual monitoring—all associated

with conventional scale inhibition. With the ClearWELL device,conventional scale-inhibitor chemicals are frequently eliminated.

No downtime

With ClearWELL technology, you can maintain production during

installation. The ClearWELL unit is mounted at the surface, without

interruption to operations. Onsite installation time is usually less

than two hours.

No pollution

Ultragreen ClearWELL technology extends the period between

scheduled maintenance, which minimizes cleanup and disposal

of hazardous wastes, such as normally occurring radioactive

materials (NORMs) and spent acid.




ClearWELLTM

Scale Control

No lost production

ClearWELL technology enables you to maintain maximum

production rates and reduce production interruptions associated

with scale remediation. With the uctuating prices of crude oil

and natural gas, lost production can be the single largest costassociated with scale deposits.

Clearly, well engineered

The ClearWELL device generates a randomly pulsed electric eld

down the length of the wellbore, including the casing and downhole

tubing, as well as through the owlines and surface equipment.

With this electric eld, the scale forms as small particles, suspended

in the bulk uid owing from the well, instead of depositing on the

metal surfaces of the well and the surface equipment.

By generating a pulsing AC current, the ClearWELL unit creates

an electric eld, induced into the wellbore as well as throughout

the wellhead and owlines. This process forces the scale to form

small crystals in the bulk uid owing out of the well, instead

of forming as thick deposits on the surfaces of the downhole and

surface well equipment.

SIGNAL DELIVERY POINT




Tried and tested—clearly, the right choice

The chart above shows real-world benchmarks from a ClearWELL installation in West Texas.

Here are some highlights:

• Eight major interventions (slickline jobs, rod pulls, etc.)

in the 12 months before installing the ClearWELL unit.

• Acid job scheduled every seven to 10 days; stopped in May,when the ClearWELL device was installed.

• ClearWELL device has kept well scale-free, without chemicals,

for more than 900 days. No scale-related well maintenance required.

Weatherford conducted independent laboratory andeld tests to prove that the ClearWELL

TM

system is

more effective against scale buildup than conventional

scale-inhibitor technology. In simulated environments

with rapid scaling of calcium carbonate and barium

sulfate, the ClearWELL system eliminated these

harmful scale deposits.

The laboratory tests were followed by two yearsof extensive commercial-scale eld tests, involving

13 different oil and gas producers in six regions around

the world. These real-world eld results were even

more impressive.

ClearWELL device in place

more than 900 days




ClearWELLTM

Scale Control

Clearly better scale control

for your applications Anywhere there’s water and scale

Producing wells

• Onshore or offshore wells

• Free-owing or articially lifted wells

• Gas, oil or coalbed-methane wells

• Wateroods, injection wells or steam-stimulated wells

• Conventional, deviated, horizontal or multilateral wells

Surface equipment

• Flowlines, pipelines or gathering systems

• Steam-injection boilers

• Valves, meters, chokes or orice plates

• Tanks, separators, heater-treaters or hydrocyclones

• Platforms and oating production facilities




Anywhere scaling is a problemEnvironmentally friendly, safer operations

Ultragreen ClearWELLTM

technology, rated for Class 1,

Zone 1, is not only friendlier to the environment, but

it also makes the workplace safer for personnel.

Traditional maintenance methods create hazardous

wastes. However, the ClearWELL device treats scale

in an environmentally safe manner, minimizing andsometimes eliminating the need for chemicals that

may or may not be successful. By eliminating the use

of hazardous chemicals and dangerous mechanical

procedures, ClearWELL technology clearly enhances

personal safety.

Easy installation, exceptional power

management

The ClearWELL device is quickly and easily clamped

on the surface equipment, near the wellhead, to treatthe entire wellbore and owlines. Even at optimal

functionality, the system consumes very low amounts

of power. The device has a built-in voltage regulator

that enables intake from a 24-VDC source, for 10 W

of power consumption—or from a source delivering

anywhere between 87 and 264 VAC, for 15 W of power

consumption. The system is also fully compatible with

solar-panel systems, thermal-electric generators, and a

wide range of other power sources.

Experienced Weatherford eld-service personnel

will review every potential ClearWELL installation.

All critical well equipment and operating parameters

will be forwarded to a core ClearWELL team, to help

ensure that the ClearWELL program produces the

expected results and cost savings.

Client eld operators will still need to routinely check

and ensure that the ClearWELL unit is receiving

power. Periodically, each ClearWELL installation

will be inspected by Weatherford, to verify that the

system is operating as expected.

Easier and more efcient monitoring

For wells equipped with automated pump controllers

or remote-data-monitoring systems, the ClearWELL

unit can be adapted to permit remote alarms if

ClearWELL power or protection is interrupted.




ClearWELLTM

Scale Control

Failure rate and number of wells pumping are shown for a

three-year time period. Signicant numbers of ClearWELL

devices were installed on the producing wells the rst year.

Note the decline in failure rate during this time period.

The results are clear

After a thorough evaluation on several test wells, one major

U.S. operator installed ClearWELL units on every well where

scale was causing frequent well failures. In the rst year, the

average well-failure rate fell by 31 percent, while at the same

time, the company was drilling more wells—increasing the

number of operating wells by 59 percent.

ClearWELL systems reduce operator wellfailure rates by 31 percent in one year

A South Texas operator wanted to increase the production

on a 6,000-ft (1,829-m) gas well that was already using

a conventional rod pump for articial lift. When a new electric

submersible pump (ESP) was installed, the well scaled up

in three days. A scale squeeze was applied, and a continuous

scale-inhibitor injection was started. The well run length was

extended to only 15 days. Then, after aClearWELL

unit wasinstalled on the wellhead, the well has since continued to

operate for more than seven months, with no scale buildup

on the ESP or owlines.

ClearWELL device extends ESP

run-length intervals from 15 days

to seven months and counting




An operator was experiencing frequent well shutdowns because

of calcium carbonate and barium sulfate scaling in a deep

13,000-ft (3,962-m), high-temperature, high-pressure (HTHP)

gas well. The operator had spent $400,000 annually to keep

the well producing, including weekly acid jobs, replacement of

corroded tubing strings and installation of expensive high-alloy

equipment. In addition, one two-month-long well workover cost

the operator $720,000 in lost production.

During the rst year after ClearWELL technology was installed,

all scale-related maintenance was eliminated. Since then, some

residual scale buildup has been removed, and the well has

continued to produce at maximum rates. No chemicals have

been needed—neither scale inhibitors nor acid jobs.

ClearWELLTM

system solves chronic scaling problem in HTHP gas well

An operator was using mist pumps to help evaporate

produced water from an evaporation pit during the summer

months. The mist pump would scale up every one to two

weeks, requiring its removal and replacement.

A short, 12-in. pipe extension was attached to the suction

of the mist pump, to enable installation of a ClearWELL unit.

After two years and two summer seasons, the mist pump has

never needed repair. The operator is now planning to install

ClearWELL units on other evaporation-pit pumps.

The patented ClearWELL unit keeps above-ground

equipment operating at peak efciency, while dramatically

reducing scale deposits. The ClearWELL unit can be easily

installed on a wide variety of oileld surface equipment—

minimizing installation costs and reducing operating

costs—without interrupting operations.

ClearWELL technology controls calcium carbonate buildup

in Utah evaporation pit




ClearWELLTM

Scale Control

Clearly integrated for your success

Ready to optimize production ow

rates and reduce maintenance costs?

Our dedicated subject-matter experts can evaluate your current lease operations

to help determine which of your wells are the best candidates for ClearWELL

technology. For more information, visit us at weatherford.com/clearwell.

In addition to the ClearWELL physical treatment system for solving scaleproblems, Weatherford offers all the eld services, equipment, analytical services

and monitoring programs to ensure your wells operate at peak performance.




weatherford.com © 2009–2013 Weatherford. All rights reserved. 4171.03

ClearWELLTM

Scale Control

Weatherford products and services are subject to the Company’s standard terms and conditions, available on request or at weatherford.com. For more information contact an authorized Weatherford representative. Unless noted

otherwise, trademarks and service marks herein are the property of Weatherford and may be registered in the United States and/or other countries. Weatherford products named herein may be protected by one or more U.S. and/

or foreign patents. Specications are subject to change without notice. Weatherford sells its products and services in accordance with the terms and conditions set forth in the applicable contract between Weatherford and the client.

To learn more about how ClearWELLTM technology can best meet

your scale-control needs, visit weatherford.force.com/CPP , and

select “Scale Inhibition”. A Weatherford representative will contact

you to discuss your options.

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