Delayed Operations: The Hurdles Facing Amman's Smelter Project

PT Amman Mineral Nusa Tenggara (AMNT) has revealed various obstacles that temporarily hampered operations at the company’s copper processing and refining facility (smelter) in West Sumbawa. The disruptions included a leak in the facility and a minor fire incident involving a component of the refining machinery.

AMNT President Director Rachmat Makkasau explained that these hurdles occurred during the production ramp-up phase from February to August 2025. He noted that the setbacks required lengthy repairs to ensure safety standards were met.

‘There were obstacles, a leak occurred in the acid cooling system, and then another leak resulted in a minor fire in the flash smelting furnace area. This happened at the beginning of 2025, which hampered production and required very extensive repairs at the time,’ he stated during a Hearing Meeting with Commission XII of the Indonesian House of Representatives in Jakarta on Tuesday.

The smelter, which utilises Double Flash technology, is designed with a concentrate input capacity of 900,000 tonnes per year. The facility is projected to produce an output of 220,000 tonnes of copper cathode, 18 tonnes of gold, 55 tonnes of silver, and 77 tonnes of selenium annually.

Following a repair process that lasted until the end of last year, the company recommenced the re-commissioning process in February 2026. As a result, the facility is now considered to be processing all concentrate production from the Batu Hijau mine as of June 2026.

‘By around April 2026, operations had started running and the ramp-up was progressing well, so that by around June 2026 we were able to process all the current production from the mine,’ he elaborated.

Although operations are now running at full capacity, the company is planning a temporary shutdown at the end of this year or early next year. This measure is intended to replace several pieces of equipment that could not be updated during the initial recovery period.

‘There are several repair jobs that are still pending, and we estimate that we will conduct another shutdown around December or January to replace some equipment,’ he concluded.