DOE-Funded 'Deep Trek' Project Yields Rugged Electronic Chips

December 5, 2007 // Published as a news service by IHS

The new components - four small electronic chips that can withstand the harsh conditions found in deep well drilling for natural gas - were developed by Honeywell International with support from the DOE Deep Trek program.

According to the DOE, most of America's natural gas comes from reservoirs located roughly one or two miles underground, but domestic production from these wells has been declining while America's dependence on natural gas is growing.

Projections show America's need for gas imports is increasing by 1.5% each year while an estimated 29% of the U.S.'s natural gas reserves remain locked in very deep reservoirs where conditions make them uneconomical to be recovered with current technology.

Drilling very deep wells, three miles and more underground, poses huge obstacles for the drilling process because of the extremely high temperatures, very hard and abrasive rock strata, intense pressure and caustic and corrosive environment - all of which can quickly wear out and disable more traditional drilling components, said the DOE.

According to DOE, without pressure- and heat-resistant "smart" drilling components, which can keep operators continuously informed about what is happening below the surface, drilling becomes almost blind, slow, very costly and sometimes off-target.

The Honeywell components will aid in reaching these deep reserves, which are estimated to contain between 169 trillion and 187 trillion cubic feet of natural gas. Using silicon-on-insulator technology capable of withstanding the very high temperatures encountered in deep wells, these critical components will serve as building blocks for downhole sensors and smart tools required to make deephole drilling economical and safe, said DOE.

The Honeywell components, all of them smaller than a postage stamp, are designed to withstand the extreme heat and pressure found in drilling deep wells.

The four components are:

• EEPROM, an electrically erasable, programmable, read-only memory chip, can store more than 32,000 eight-bit data words. It can be programmed, as well as read, at high temperatures and retain data for more than 1,000 hours at 225 degrees Celsius (C) (437 degrees Fahrenheit (F)). Having a non-volatile memory, the EEPROM can retain information when the power is off.

• FPGA, a field-programmable gate array equipped with more than 3 million transistors, features programmable logic functions and interconnections, including the equivalent of 32,000 user-configurable logic gates. This flexible chip can be reprogrammed in the field if there is a change in purpose for a particular electronic circuit. The FPGA receives instructions from the EEPROM.

• OpAmp (Operational Amplifier) amplifies and conditions low-level signals received from downhole sensors. The OpAmp can operate at temperatures from -50 degrees C to 375 degrees C (-58 degrees F to 707 degrees F). In testing, this precision amplifier performed well at 300 degrees C for more than 1,000 hours.

• ADC, an 18-bit analog-to-digital converter, has a 16-fold improvement of resolution over existing technology. The ADC converts continuously variable voltage to digital data words, translating voltage to a binary digital number.

Honeywell is working with DOE on a follow-up project to combine the FPGA and EEPROM chips into a rugged, reconfigurable and flexible ceramic processor package that can be customized to meet individual tool requirements and help drillers tap America's deep gas reservoirs.

DOE launched the Deep Trek program in 2001 to develop innovative and tough deepwell technologies such as smart communication tools, pipe systems, novel drill bits and drilling fluids. These advanced technologies have to withstand the extreme pressures (more than 15,000 pounds per square inch) and temperatures (over 205 degrees C or 400 degrees F) that are typically encountered in deephole drilling.

The DOE National Energy Technology Laboratory manages the Deep Trek program for DOE Office of Fossil Energy. To date, 19 Deep Trek research and development agreements have been awarded at a total cost of more than $36 million, which includes $12 million in contributions from research partners.

Source: U.S. Department of Energy (DOE) Office of Fossil Energy.