New technologies will tackle the problem of producing oil and gas from tough spots.

Many would agree that the top picks for high-impact emerging E&P technologies of the 1980s and 1990s were the innovations that led to effective 3-D seismic imaging and highly deviated drilling. These innovations have made it much easier to locate and access the oil and gas accumulations that are becoming harder to find and exploit. Quite a few of the current crop of emerging technologies however, appear to be focused on the production end of the process. Specifically, how to economically produce accumulations that are smaller in size and more remote than in the past. Two areas where emerging technology breakthroughs can be expected to have a significant impact are subsea production processing and innovative solutions to the problem of stranded gas.

In the words of David Walker, one of BP's distinguished advisors on deepwater strategy and a 2002 SPE distinguished lecturer on the topic, "The subsea engineer owns the future." Walker's perspective is that subsea processing will eventually be required to ensure high recoveries from the most remote ultradeepwater locations, and that some technology jumps will be needed to get there. Unfortunately, these jumps will need to happen soon, without a lot of time for learning from the ultradeepwater projects currently under way. "We are producing from just over 7,000 feet (2,135 m) of water but exploring in 10,000 feet (3,050 m), and the cycle time between discovery and production is dropping with each new development," says Walker.

The potential for subsea processing arises from the difficulty of maintaining flow through increasingly long flow lines. Problems with wax deposition and hydrate formation in particular can be exacerbated by the deepwater temperature environment. In addition, for marginal, remote accumulations, the cost of adding separation capacity on the surface may be prohibitive. A number of companies are working on this.
Kvaerner Process Systems is developing a compact coalescer that at first will be demonstrated for topside duty and later in a subsea version. Framo Engineering's centrifugal separator, currently being tested on the Petrojarl 1 floating production, storage and offloading (FPSO) vessel will be tested in a subsea pilot through the DEMO 2000 program launched by the Norwegian government to support the development of subsea systems. Another technology well suited for subsea applications is cyclone separation. FMC Kongsberg Subsea is working with Shell's Twister BV company to develop a subsea supersonic cyclonic separator. Simplicity and reliability are critical factors in subsea processing, and the Twister requires neither chemicals nor rotating parts. The current feasibility study phase would lead to the operation of a subsea plant in 2003-04.

GE Oil & Gas and Kvaerner Eureka of Norway have completed the joint development of a subsea compression module that features a 2.5-MW Blue-C subsea centrifugal compressor. The module is a turnkey system capable of handling natural gas at pressures up to 1,900 psi that can transport the well stream to a central platform or directly to an onshore site, at distances of up to 50-60 miles (80-100 km). Plans to develop an even larger, 5-MW module also are under way.

Other important subsea processing challenges will deal with sand production, producing the power needed to drive the equipment and providing pumping capability. SEPDIS (Subsea Electrical Power Distribution System) is a system being developed by ABB through a JIP program with participation by oil companies. Several seabed pressure boosting projects are also under development.

A second area where new technologies are emerging is in the economic development of natural gas accumulations, both onshore and offshore, that are insufficient to justify a pipeline to market. Estimates of the volume of stranded gas worldwide vary, but a study by Petroconsultants MAI and ZEUS Development Corp. puts the total at more than 900 Tcf.

Technologies being developed to monetize this stranded gas include gas-to-liquids processes (Fischer-Tropsch production of liquid hydrocarbon products from syngas produced from natural gas) and innovative liquefied natural gas (LNG) technologies. A number of plans for floating GTL or LNG plants have been envisioned. The demand for natural gas has driven a significant increase in LNG activity, particularly in the Atlantic basin, but two problems remain: the huge cost of liquefaction plants and the reluctance to have LNG terminals near population centers.

A novel technology that sidesteps the problems encountered when attempting to site LNG terminals near population centers is the Energy Bridge system being developed by El Paso Global LNG. El Paso is in the process of modifying three LNG tankers to allow them to regasify LNG onboard and deliver the gas into a pipeline via an offshore mooring buoy system and subsea pipeline. The tankers would dock for several days, delivering gas at a rate of up to 400 MMcf/d. An empty tanker would be replaced by a full one, maintaining essentially constant delivery. The first of the converted tankers will be completed in the fourth quarter of 2004, about the same time El Paso hopes to have their first mooring buoy system and pipeline installed, most likely in the Gulf of Mexico. Similar buoys could be installed near practically any coastal population center.

On the other end of the LNG chain, new technologies are emerging that may make it feasible to liquefy relatively small accumulations of gas without the enormous investment required for conventional liquefaction plants. One of these, a thermoacoustic natural-gas liquefier, uses thermal effects of sound to refrigerate and liquefy natural gas. Los Alamos National Laboratory and Praxair have built a 500-gal/d system and are envisioning a 10,000-gal/d version that could be transported to remote areas or installed on an LNG tanker. The system is expected to liquefy 80% of its throughput, and researchers expect that further improvements eventually can bring the efficiency close to 90% without compromising the low cost and simplicity (no moving parts) of the thermoacoustic approach. Such a system could be used to economically produce natural gas from remote locations.

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