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Alstom’s offer to the Aluminium Industry

Through continuous development for more than 50 years, Alstom has maintained a leading position as a supplier to the aluminium industry. Alstom offers a complete range of systems, components and services of environmental control technologies, covering design, manufacture and installation as well as commissioning and long term maintenance. Alstom provides expert assistance from initial concept development through every stage of the project management process. It has unique expertise in system integration and management of turnkey projects.

Abart

Abart is Alstom’s unique patented dry scrubbing emission control solution for the aluminium industry. It is the most compact, high performance and cost-competitive solution available today. An integrated two-step process, with proven benefits of fresh alumina added on filter bags in a counter-current operation for optimum abatement of hydrogen fluoride emission.

To cost effectively master HF absorption in the continuously increasing pot off gas temperatures of higher amperage pots, Alstom has developed a new innovative Heat Exchanger. This cools down the gas for optimal HF absorption in the Abart.

Alstom Abart Pre-reactor for Retrofit offers a cost-effective solution to significantly boost the performance of existing dry hydrogen fluoride emission scrubbers. It has the benefit of extremely low pressure drop combined with high removal efficiencies.

Impulse Duct and Forced Suction System

The gas flow to the Abart is led through a patented Impulse Duct, which reduces the pressure drop significantly compared to conventional arrangements. This unique duct system evacuates the gas equally from the pots.

Alstom has developed a Forced Suction System to deal with emission peaks, during events like metal tapping or anode change. A pneumatically operated diverter valve closes off the normal flow from the cell and opens up to a separate duct connected to a booster fan. The forced suction gas is mixed in a balanced way with the gas from the cells under normal operation to secure optimal gas distribution in the Abart reactors and filter compartments.

Pot Feed System

The Alstom pot feed system called Alfeed, transports the enriched alumina from the silo directly into each individual pot. It is a horizontal distribution system based on a supply-on-demand concept. The main air slide is located alongside the pot room building and the other is on the pot superstructure. The latter one have outlets filling up each pot hopper as alumina is consumed in the pot point feeder systems and pots. The Alfeed system is completely enclosed and the exhaust air is led into the collecting gas ducts for the Abart. Thus the fines are contained with the system and distributed evenly among the pots. The Alfeed equipment design is slim and integrates well on top of the pot superstructure. The system consists of a limited number of modules thus reducing the number of spare parts and allowing for easy and cost efficient maintenance. These design elements make the Alfeed System ideal for both new installations and retrofits.

Green Anode and Anode Baking

Alstom is a world leader in treating gases from green anode plants and anode baking furnaces as well as cast houses. Our systems work with open or closed baking furnaces. Gas treatment systems typically includes direct / indirect coolers, horizontal electrostatic precipitators, bag filters and heated poppet dampers.

SO2 abatement

Alstom’s long experience in supplying efficient SO2 abatement solutions to the Aluminium and other industries, gives it the capability to offer the optimal solution for each case. Whether Dry Flue Gas Desulfurization (using lime or bicarbonate), Wet Flue Gas Desulfurization (using limestone or sodium hydroxide) or Seawater Flue Gas Desulfurization (using seawater) is selected Alstom has a reference.

 

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