Based in North Somerset, the plant has been supplying the construction industry with building material for more than 60 years. It uses large quantities of gas to heat and dry the 250,000 tonnes of asphalt produced each year, and as the site is active 24/7, maintaining a constant, reliable supply of fuel plays a vital role in hitting production targets and meeting customer demand.
The site is located off the mains gas grid, and until recently the plant’s burners were fuelled with kerosene. After seeing an opportunity to reduce both emissions and fuel bills, Aggregate Industries approached Calor about working together on a new heating solution.
“We made the switch to LNG because it is a cleaner source of energy,” says Plant Manager Simon Evans. “We were previously using kerosene, but LNG is a more cost-effective product to burn. It also produces a lot less carbon, and reducing our carbon footprint is very important for Aggregate Industries.”
As well as substantially cutting fuel costs, the project has reduced the amount of CO2 emitted per tonne of asphalt produced at the site by 17%. This cuts Aggregate Industries’ annual emissions by 1,800 tonnes.
A UK first
The site is the first asphalt plant in the UK to use LNG and only the second in the entire world. It also represents Calor’s first turnkey LNG installation in the UK.
The commissioning project began in January 2015 and was completed in May. As well as laying new pipework and converting the site’s 16MW burner to run on LNG, Calor installed a 90m3 tank and a pair of vaporisers each capable of converting 2,000m3 of gas each hour.
Evans says: “The relationship between Aggregate Industries and Calor during this project was very good. We got on very well, and built up the relationship that helped us get to where we did with the project.
“The experience has been good. I would recommend Calor as a supply company; they did a very good job.”
A reliable supplier
One of the most important requirements of Aggregate Industries was that the site’s supply needed to be extremely reliable, as any interruption in operations would be costly. Calor has ensured that there is never any risk of the site running too low on LNG by installing a telemetry system that continually measures tank levels. As soon as the level gets low, the company automatically arranges a delivery.
“They can measure the level of gas in a tank, and they supply us with that information too,” Evans explains. “We’re currently having about two to three loads of LNG a week and that’s all delivered without us having to order it.”