Syngas cooler tube leaks fixed, Kemper aims for end April finish

Southern Company and its subsidiaries have a long and impressive track record of innovation. For example the website mentions Tomlinson Fort Johnson, a Georgia Power engineer who in 1916 created a way for line crews to replace faulty insulators while lines were still energised, “drastically reducing outages at a time when customers were just beginning to use electricity.”

The company has maintained a penchant for pursuing complex and challenging high-risk first of a kind power technology projects. For example there are the Vogtle 3 and 4 AP1000 pressurised water reactor projects, where schedule and cost overruns have contributed to Westinghouse’s current financial difficulties, and the 582 MW Kemper County lignite fuelled IGCC plant (pictured), where cost estimates are now running at more than $7.2 billion (over three times the original (2004) estimate of $2.2 billion).

The most recent among a host of problems that have been addressed (and to some extent to be expected in a facility of this size and complexity (see site photograph), combining as it does power generation technology with features characteristic of a chemical facility) was tube leaks in the syngas coolers.

At the time of writing it was hoped to have the facility in service by 30 April. The tube repairs had been completed and the new schedule was said to reflect “the time needed for restarting that portion of the plant and to achieve integrated operation of all plant systems.”

Integrated operation includes the simultaneous operation of each of the plant’s two gasification, gas cleanup, and generation trains. While the repair was required for the syngas cooler of one gasification system, the other gasification system remained in operation and “has been providing clean syngas for chemical product production and electric power generation”, said Southern Company subsidiary Mississippi Power, which is the plant developer, owner and operator.

In February Mississippi Power had said it hoped to have the plant in operation by mid March pending resolution of problems with the ash removal system in one of the gasifiers. In early 2017 the plant had achieved integrated operation of both gasifiers, including the production of electricity from syngas by both combustion turbines, and had also captured CO2 and placed it in the pipeline for EOR.

Unfortunately, as well as project cost increases, the economic case for the plant has also been greatly weakened by persistent low natural gas prices.

Under a 2012 order from the Mississippi Public Service Commission Mississippi Power is required to carry out analysis of Kemper’s economic viability, with the aim of assessing the economics of the project compared to feasible alternatives, including natural gas combined cycle generating units.

The most recent analysis, according to Mississippi Power, indicates that “primarily a reduction in projected long-term natural gas prices, and to a lesser extent an increase in operating costs of the project, negatively impact the economic viability of Kemper.”