Electric-drive centrifugal compressors replace recips in gas treatment

Siemens was recently awarded a contract to provide three residue compression trains for two, 250 million (500 million total) standard cubic feet per day (MMSCFD) cryogenic gas plants in the Delaware Basin.

Each train consists of a 22,000 horsepower (hp) motor, gearbox, and multi-stage Dresser-Rand DATUM centrifugal compressor, all mounted onto a single skid. The compressors, motors, and drives will all be built by Siemens in the USA and is scheduled for commissioning the latter part of 2020.

Mid-size gas treatment plants traditionally use reciprocating compressors driven by electric motors or gas engines. However, with the increase in production from shale plays, larger gas plants – in the range of 200-300 MMSCFD – are being constructed, forcing gas processing companies to consider alternative compression solutions in order to reduce costs, footprint, and maintenance.

While the traditional approach would require 10 large reciprocating units for this project, Siemens’ centrifugal compressor solution met the entire plant duty for this two x 250 MMSCFD project using just three compression units while ensuring low turndown capability. The plot space and the ancillary infrastructure – such as foundations, piping, wiring, cabling and electrical systems – was also remarkably reduced resulting in significant capital cost savings for the customer.

The high efficiency of the DATUM compressors, coupled with their easy maintenance, was a major factor for selecting this configuration. With a DATUM fleet availability of more than 99.7%, the plant will have minimum downtime despite the un-spared compressor configuration and will ensure minimal loss of production, bringing significant value to the customer in meeting contractual production guarantees.

“This project is an excellent example of Siemens’ ability to offer its customers a complete integrated solution,” said Patrice Laporte, Vice President of Oil and Gas for Siemens America. “This customer is one of the largest shale gas players in the Permian Basin and this is their first order with us. For them to switch from their traditional approach to our proposed solution lends testament to their confidence in our understanding their needs and having the technical expertise to offer a customized, innovative offering,” Laporte added.