Lanes praised for “ingenuity” of animal feed tank disposal
Lanes Group engineers have been praised for their ingenuity and meticulous planning after successfully removing a large storage tank that had contained more than 29 tonnes of animal fat.
The tank, which weighed 10 tonnes, had stood idle for more than 15 years at pig and poultry feed makers ABN in Northallerton, North Yorkshire.
The project to remove and dispose of the 13 metre high structure was so complicated it took over a year to plan, then the lift had to be millimetre perfect.
The tank was surrounded on three sides by taller buildings, was actually touching one of the factory walls. It also had to be lifted over a large electrical sub-station.
Andy Sadler, Operations Manager at ABN Northallerton, North Yorkshire, said: “The Lanes team was very impressive, both in the meticulous way they planned the lift and the ingenuity of its execution.
“Lanes Group handles all our on-site drainage work, so I asked them how they would go about removing the tank, which was a major eyesore and took up useful space.
“They submitted a detailed plan to dispose of the fat and remove the tank. I consulted other companies, but Lanes put forward by far the most sensible solution.”
The project was led by Ian Sullivan, Regional Manager of Lanes Group’s Teesside depot at Stockton-On-Tees, who visited the site almost every week for a year to develop the lift plan.
His previous experience working in industrial services helped prepare him for planning and managing such a highly complicated and delicate operation.
He added: “This work is not a core Lanes Group service but it demonstrates the capabilities, knowledge and experience we can bring to bear to help our clients.
“Because the tank had not been used for more than a decade we needed to carry out careful checks to make sure our disposal plan could be implemented safely.”
This involved sampling the fat to make sure it was safe, identifying a way to take it out, then planning a safe and effective lift to remove the tank.
The fat had set into a hardened mass, so the team inserted a steam heating coil through a hatch at the top of the tank and pumped steam through coils already in place in the base.
This mobilised the fat, turning it into a liquid, so one of Lanes Group’s powerful JHL jet vac tankers could suck it out.
The tank was then cleaned using a technique called ‘spin washing’. This involved modifying a high volume Butterworth water jet, so it would spin around inside the tank.
Because the tank was so old, structural tests were carried out to assess its strength and how it would respond when lifted.
One test showed the lifting lugs on the tank were too degraded to use safely. Welding on new lugs or using heat-based cutting to create new anchor points were not options because of the fire risk.
So a technique called cold cutting was used to create holes at the top and bottom of the tank to attach lifting chains and cut the tank from its base.
With cold cutting, thin jets of water at ultra-high pressure, around 40,000 psi, are used to cut through materials, such as plate steel. An abrasive grit-like substance is added to aid the cutting process.
Once the tank was prepared, two cranes were brought in. One was used to lift the tank away, the other to tilt it horizontally so it could be placed on a lorry and taken away.
Ian Sullivan said: “After months of planning, we had a window of one day to carry out the lift. It was a bit of a nervous moment but it went perfectly.
“The tank had been touching one of the buildings and had to be lifted over the mill’s electrical sub-station, which is housed in a four metre high building. It was a precision operation.
“I am very proud of how we managed the project. We were able to bring together a team of external experts to solve the problem methodically, safely and cost-effectively.”
Lanes Group is now making good the space left by the tank, be rechanneling guttering on the building and resealing the bund in which the tank stood.
Andy Sadler said: “This was a very complicated project and there was a lot to go wrong if it hadn’t been handled properly.
“The Lanes team at Stockton, and Ian in particular, have shown they are can-do people. The space where that ugly tank once stood proves it.”