The EnPot system was installed in February 2025 at the Binzhou Beihai Huihong New Materials Co. Ltd. Smelter on six 440kA pots. 

Until this time the technology has been installed on pots ranging from 160-340kA. As such, the new installation set out to demonstrate the effectiveness and safety of the technology on the largest pots to date.

The EnPot engineering team spent three months testing large changes in cell heat extraction or conservation. The process is ongoing; however, results show the EnPot technology enabled both very effective shell cooling and insulating on the 440kA pots. 

The EnPot technology features stainless-steel Shell Heat Exchanger units attached to the upper sidewall of each pot, as seen below. Heat transfer control is maximised by the exchangers covering a large surface area of the pot, in the hottest shell location.

Each exchanger is connected via suction manifolds to branch ducts and then to the main suction duct and fan located outside the potroom.

 EnPot system schematic

The system design was customised for the Beihai pot shell by EnPot, with all pot-side hardware manufactured and shipped from New Zealand to China.

The ducting, fans, and electrical and instrumentation equipment were supplied locally, including site installation labour.

The Beihai design features 96 heat exchangers and ten manifolds per pot, which can be controlled independently to improve the thermal condition and regularity of the pot, while maintaining operational stability and safety. 

EnPot Technology mounted on the pot shell sidewall 

Initial results

The EnPot team, together with the support of smelter operators and engineers, performed a wide range of tests to rapidly build a picture of the basic behaviour of the system and effectiveness on the large high-amperage pots.

Key highlights of the initial tests include successful stable operation with +10% high heat generation for 2 weeks, +15% for 2 weeks, and +20% for 8 hours, with many short duration tests of both positive and negative heat generation.

Another key benefit of shell thermal control included the ability to extend the life of the pots in a full shutdown scenario from four to six hours or longer, with further extended shutdown ability expected in future. Another benefit was seen by operating the pots utilising EnPot’s insulation ability for 2% power conservation without current efficiency loss, with the expectation of further reductions.

EnPot’s external ducting and fans