Two firms have suspended ammonia production because of the high cost of natural gas and will restart only when gas prices allow profitable operations. A third firm, unencumbered by such costs, will increase capacity. LSB Industries' Cherokee Nitrogen subsidiary suspended ammonia production and will fill customer orders from inventory and purchased ammonia. Terra Industries has shut its Yazoo City, Miss., ammonia facility. After a maintenance turnaround, Terra says, it will restart the plant when gas costs decrease. But Coffeyville Resources says it will boost both ammonia and urea ammonium nitrate capacity, including an increase in the latter from 650,000 tons to more than 1 million tons per year. Expansion of a gasifier to increase hydrogen production used in the firm's refinery operations—part of an overall $92 million capital project—will allow excess hydrogen to be converted to ammonia. Coffeyville, formerly part of Farmland Industries and now owned by private investors, says it is the only nitrogen fertilizer maker in North America that uses petroleum coke as the feedstock for its gasification process.