Bridgnorth Aluminium manufactures lithographic aluminium strip with a purpose built, state of the art rolling mill and stretch levelling line in its Shropshire site.  The company is focussed on maintaining a clean alloy system with its high purity aluminium alloy product range, which requires considerable technical knowledge of the process requirements.

As part of a planned expansion, Bridgnorth Aluminium purchased a refurbished rolling mill from overseas. As with all rolling mills that use oil as a coolant and lubricant, amounts of oil are emitted in their exhaust. In line with best practice, the company has installed an Achenbach Airpure exhaust air purification system to separate and recover hydrocarbons from the mill exhaust – in this case tetracene.

Babcock Wanson’s TPC 200B Thermal Fluid system forms an integral part of this process, heating exhaust air to enable the Airpure system to recover virtually all rolling oil. Babcock Wanson not only supplied the new TPC 200B thermal fluid system, but was also involved in laying out the pipework and connections to the heat exchangers. 

The TPC 200B is a fully automatic coil type, multi-pass thermal fluid heater complete with integrated burner, control system and safety devices. It is said to provide optimal distribution of the heat, high fluid velocity in the exchange tubes and continuous flow monitoring to ensure long thermal fluid and system life and high levels of safety.  

Peter Shrimpton, engineering projects ,anager at Bridgnorth Aluminium, says: "The original manufacturers of the rolling mill equipment recommended that we use a thermal fluid system as part of the exhaust air purification system. We hadn’t used this before and were unfamiliar with Babcock Wanson, but we’ve had no problems with it whatsoever; you simply switch it on and it works – simple as that. The service we have received from Babcock Wanson has also been great.”

Whilst Bridgnorth Aluminium hasn’t been using the system long enough to gather comprehensive energy efficiency data, it is expecting considerable energy savings.  Babcock Wanson claims between 20 and 50% energy savings can be made by using a TPC B thermal fluid heating system, when compared to the transfer of the same amount of heat using traditional steam boilers. These savings are achieved as the thermal fluid does not need to change state to transfer the heat, as would be the case with steam, which means no trap losses, no blowdown losses and no flash steam losses. This also makes for simpler operation and low maintenance needs.  With lower energy input demand also come lower total exhaust emissions so thermal fluid systems are much kinder to the environment.