Brisbane-based Aurizon has posted a $341 million half-year profit, an increase of 51 per cent as it accounted for the $105 million sale of its rail grinding business.

Its underlying profit was up 19 per cent to $269 million.

Shareholders will receive an improved dividend of 13.7c a share, 70 per cent franked while its full-year earnings guidance remained between $880 million to $930 million.

Aurizon has also boosted its share buyback by $100 million.

The healthy profit included a warning that its coal haulage outlook had been reduced because of customer production issues and maintenance priorities. The expectation was for an improved second half and volume forecasts for the full year are in the range of 210-220 million tonnes, down 10 million tonnes

Aurizon chief executive Andrew Harding said the profit was a solid performance and a key factor was the UT5 undertaking with its Central Queensland Network customers.

“In the coal business, we executed two contracts with existing customers, Peabody and Coronado, both involving an extension of contract terms and additional tonnages,” Harding said.

He said demand for coal would continue to increase over the next decade.