New Generation anode baking technology:
securing a sustainable operation

The industrial prototype of the New Generation Anode Baking technology celebrated its third year of successful operation in Bell Bay Aluminium in December 2020, with 66 fire cycles.

With 6 sections converted to this patented technology, the productivity has been increased by 15% due to the partial removal of the headwalls. This allowed Bell Bay Aluminium to produce 24 000 additional anodes since 2017 with a confirmed 30% reduction in gas consumption and with no impact on anode quality. As a reminder these gains made the business case positive after only 1 ½ years.

The operation and maintenance of this breakthrough technology has obviously raised some challenges which have been overcome with the development of new tools and operation/maintenance procedures.

The natural tendency of the long fluewalls (33 meters!) to bend has been kept under control with the use of straightening devices between the unloading and loading operations. These light tools have been engineered to easily re-straighten the fluewalls in some specific areas. The furnace tending assembly is not required during this operation and the employees are not exposed to additional HSE risks. This has successfully allowed to keep the pit width within the usual range for a standard technology.

Over the last year, the fluewalls have begun to show some pinching under the burner peepholes and some maintenance has been done to repair those areas with V-shape replacement on the upper part of the fluewalls.

These learnings have allowed us to improve the design and the technology package for the New Generation ABF technology, thanks to the commitment of the teams in Bell-Bay and in our technology centers.

This prototype ABF area will probably be replaced in the coming months after ca. 80 fire cycles. The success of this prototype has led the plant to decide to rebuild this area with the same technology and to convert another 6-section area in 2022.

The objective of those new areas will be to validate the slight improvements done to the design based on the learnings from the prototype, which target increases fluewall life.

Order of Magnitude study to increase Hindalco Renukoot productivity

Hindalco operates at Renukoot (Uttar Pradesh, India) across the aluminium value chain from bauxite mining, alumina refining, aluminium smelting to downstream rolling and extrusions. Anode baking facilities are composed of three furnaces with a total production capacity of 260 kt/year approximately and the oldest started in the 1960s.

AP Technology currently supports the Renukoot team for the Order of Magnitude (OoM) study to increase the production capacity of its latest furnace constructed in 2014 (130 kt/year of baked anodes). Several scenarios, going from existing facilities’ extension to new workshop erection, are analyzed in terms of technical features, operability and costs. Through AP Technology expertise and modelling tools for process management and operation management, Hindalco will be able to select the most suitable facility and refractory design for Renukoot site constraints. This will furthermore confirm Hindalco leadership position in aluminium smelting and production in India.


In 2020, it was planned to refurbish both furnaces (48 sections with 7 pits per section) in Alma.

Despite Covid context, Rio Tinto successfully performed retrofit and raising of approx. 0.6m on one furnace. The great collaboration between the project team and the bricklaying company allowed Rio Tinto to meet the challenge of keeping the project on track. The work duration took longer in order to respect all health regulations.

In 2021, the objective is to renovate the second furnace faster, whilst maintaining a high level of HSE standards for the project. AP Technology™ carbon team will continue to support the project team for the construction and the start-up of the furnace.


Maintaining the assets at our smelters, such as the anode baking furnace, is a key part of ensuring safe and stable operations. However, maintenance and rebuild activities need to be managed to ensure continuity of anode supply by either building extra inventories prior to work execution and/or purchasing extra anodes. Therefore, it’s important to complete the works as safely and quickly as possible to minimise production and financial impacts for the operation. 

With this in mind, the AP Technology™ Carbon team, in co-operation with the Rio Tinto Pacific Smelting Technical Support and Boyne Smelters Limited (BSL) Carbon teams, developed a new concept to prefabricate the smelter’s CBF4 headwall while the existing furnace design is also being rebuilt (total 66 sections with 8 pits per section, original AP Technology™ design).

AP Technology™ headwalls are traditionally built in-situ. However, this involves a number of challenges and risks for operators. With this new approach, the headwall can be built outside of the furnace and installed as pre-built modules, offering significant advantages over in-situ headwalls such as improved safety and ergonomics, and quicker turnaround time. The technical challenge, however, is to guarantee the prefabricated headwall has the same mechanical strength and integrity over time as the in-situ assembly. The first trial of this concept for an AP Technology™ furnace design will be performed on BSL’s CBF4 by the end 2021.