Taking action to reduce energy, carbon emissions and improving resource efficiency

Who are Bridge Thermoplastics

Bridge Thermoplastics produces uPVC profiles for a variety of sectors and customers, using for the most part recycled plastic. An expansion of the company has resulted in the production of a wide variety of custom profiles and this had resulted in the cooling capacity of the cold-water chiller system reaching its maximum output. The site has seven different lines for producing a broad range of plastic profiles, and each line can be adapted to make a different profile. The company uses water baths that the profiles run through and cooling water fed directly into a 'calibrator' to cool the profiles.

Why did they engage with DE-Carbonise?

Bridge Thermoplastics' challenge was calculating the cooling demand to design an appropriate cooling system. Recycled PVC is used in the extrusion process for larger decking plastic. Bridge Thermoplastics has struggled over the cooling process post-extrusion for larger decking plastic. The identification of the maximum cooling demand from the largest profiles allowed Bridge Thermoplastics to schedule work more effectively so that the maximum output of the chiller was not exceeded.
It was also established that the chillers had sufficient capacity for most of the work planned, but that bottlenecks in the system were caused by pump capacity and the size of the heat exchanger.

What has been the impact of working with DE-Carbonise?

In the summer of 2020, Bridge Thermoplastics engaged with the DE-Carbonise team and the City Council carried out an on-site carbon reduction audit, producing a report providing advice on reducing energy, resource efficiency and carbon emissions. Key recommendations from this included upgrading lighting to LED, considering solar photovoltaic panels as part of a roof replacement, and undertaking a compressed air audit. A requirement was also identified to address the cooling needs of the business. Bridge Thermoplastics then started working with the UoD to identify the maximum cooling demand from the largest profiles.

Dr. Hirbod Varasteh, a Researcher from the University of Derby, determined whether the two chillers on site could provide sufficient cooling for the target volumes of plastic production. He also analysed the data to see if there was a clear gap between the cooling capacity and the demand. Hirbod’s report aimed to improve the cooling system of Bridge Thermoplastics by considering the size of the chiller, pump, and heat exchanger.

It was identified that the cooling system's bottlenecks needed to be fixed to improve efficiency and reduce carbon emissions. Work carried out by the DE-Carbonise team identified that there was a clear gap between the cooling capacity and the demand so consideration was given to how to remove the bottlenecks and improve efficiency and, thereby, saving carbon.

Hirbod identified that Bridge Thermoplastics’ cooling system had issues: the cooling tank was set at 12oC, but the cooling water temperature spiked to 16-18oC. This resulted in a reduction in production quality and production rate as well as an increase in operating costs and carbon emissions.

Calculations showed that Bridge Thermoplastics needed to have an appropriate size pump and heat exchanger to achieve an efficient cooling system with the available chiller. Pump flow rate was one of the main bottlenecks. The pump needed to have a sufficient flow rate to transfer heat from the cooling bath to the chiller. Also, an appropriate design of the heat exchanger was essential. It was also determined that the chillers had enough capacity for most of the work planned, but that bottlenecks in the system were caused by the pump capacity and the size of the heat exchanger. Hirbod recommended the best option for the cooling system design to improve efficiency and reduce carbon emissions.

The recommended options can solve Bridge Thermoplastic’s issues and provide the required cooling temperature with a lower pump flow rate and higher efficiency. It has allowed Bridge Thermoplastics to schedule work more effectively so that the maximum output of the chiller was not exceeded.

A grant administered by Tom at Derby City Council, enabled Bridge Thermoplastics to replace the heat exchangers with a larger plate model, which could be expanded easily to cope with larger cooling demands if required. The company took this opportunity to simplify the cooling pipework and upgrade the pumps.

At the same time the grant was also used to replace all lights within the factory with LED lighting, which made a vast improvement to light levels and is forecast to save 6.5 tonnes of carbon emissions per annum. Advice from the team has also been taken to reduce compressed air use and repair leaks in the pipes, with plans to upgrade the compressors to variable speed models in the future.

• Actual annual energy saving (kWh): 23,326
• Actual annual carbon saving (KgCO2e): 6,468
• Actual annual cost saving: £2,959.00
• Actual grant: £6745.60

“As a small business we wondered if we were too small to be helped, but we found that the DE-Carbonise Team was extremely helpful and able to work alongside us to consider our options.”

About DE-Carbonise

DE-Carbonise is a three year collaboration between the University of Derby, Derby City Council and Derbyshire County Council, which started in November 2019. The collaboration is funded by the European Regional Development Fund (ERDF) and follows on from the successful D2 Energy Efficiency/Low Carbon project.

Get in contact with us

To find out about current support available for your business in reducing your environmental impact, or your journey to net-zero. Please get in contact with our business gateway team.

Call usEmail usMake an enquiry