Richard Franklin: Cool about Hot Oil

An essential part of any panel press remains generally unseen and receives little in the way of attention or publicity; yet it lies at the heart of the entire production process. Presses, whether continuous or daylight, are heated. The thermal oil that does the heating is at high pressure and temperature. Should it escape it can pose a major source of risk.

“A large part of our business essentially consists of managing and reducing this risk,” says Richard Franklin. “Wood based panel makers are experts at making panels; they are not necessarily experts at how to handle and reduce the risk of high-pressure, and very hot, oil escaping into an environment of wood chips and dust. Clearly that is a very hazardous combination; and a large part of the service that we offer is knowing how to monitor, handle and reduce the risk, and passing on that knowledge. We have clients in many industries that use thermal oils but the panel business is our major client base.”

With Norbord, Arauco, Georgia-Pacific, Louisiana-Pacific and Weyerhaeuser among its clients, that claim is clearly true. The company is based in Britain, in Buxton in Derbyshire. “We have been in the US for 10 years now, but we now need a formal subsidiary there,” says Mr Franklin. That is why the company’s new subsidiary, Thermal Oil Solutions Inc, is setting up in Greenville, South Carolina now.

“The company started 25 years ago, testing and analysing and also as a supplier of heat transfer fluids. Today we have three sides to the business: a contract design service; a lab side testing the fluids; and a service division to maintain their safety and stability.”

Here is Mr Franklin on what he calls the joys of thermal fluids. “It is the ideal medium for high-temperature heat transfer in industry. For low temperature heating, up to about 200oC you can use steam under pressure; but panel makers are typically operating their presses at up to 300oC. Steam would need to be more than 100 bar to achieve such temperatures, but thermal oils can operate in that region at pressures barely more than atmospheric.” Nevertheless, thermal oil is far from problem-free. “At those temperatures, the oils are operating close to their flash-points – which makes them flammable and hazardous,” says Mr Franklin.

Normally, of course, the thermal oils heating a panel press are in a closed system, which considerably reduces the hazard; but should a mechanical or procedural failure let them escape, the environment around them is full of wood chips and dust. The result would be, says Mr Franklin, “a toxic fire risk made in hell”.

It is to avoid that that companies such as Norbord and Arauco employ him. “Our specialism is the costs and safety issues surrounding the operation of thermal oil systems.

“We began developing our expertise in Europe around the year 2000, when the ATEX regulations came in.”

These European directives required operators whose work involved potentially explosive atmospheres to develop risk assessments. “The directives were designed for the petro-chemical worlds. It had not been foreseen that for many operators, such as the food industry, the hazard was limited to just one part of their operations – frying in their case – and that the vast majority of what they did was free of such hazards. Users were getting a raw deal because they were expected to be expert in areas not their own.

“It was the same in the panel industry. Norbord, who were big clients of ours, asked us to help. That’s where I started giving assistance in managing risk,” says Mr Franklin. The company offers a design service for thermal oil installations, but the problems do not stop with design. With use, and over time, thermal oils start to degrade and their flash-point decreases, making the likelihood of an incident even greater.

"The flash-point can go down by 100o degrees or more; which can mean you are running an oil at 300o degrees when its flashpoint is only 200. ‘Flashpoint recovery’ is one service that we offer. Our labs can test oil to see how flammable it is getting. "Mechanical failure is not the only thing that can set off an incident. Cavitation round the pumps can set oil on fire; process failures can increase the rate of flash point decay,” explains the MD.

The degradation of thermal oil is itself a thermally-caused phenomenon. “This makes a special difficulty in the panel industry. A press operator can tell us that his oil is being operated at 270o, so its 300o flashpoint should last 20 years. But panel plants are generally heated by biomass. You can turn presses on and off – they have to be halted occasionally, once a day or once a month – but you cannot turn a wood-fuelled combustion unit on and off with a switch.

So whenever the presses are halted, the oil in them is no longer unloading its heat to them but is still being heated itself, so it gets hotter; and that increases the rate of degradation. With that happening several times a month, your supposed 20-year stability of flashpoint goes out of the window," continues Mr Franklin.

“And a panel plant may have half a million litres of oil at 290o or more in its system. That is a huge risk, should it get out.

“The standard industry way of establishing best practice is by precedent: look at an incident and learn from it so that it does not happen again. It is industry-led, and it works; but it is reactive. My biggest customer, Norbord, looked at it and said ‘Can we get better at this? There is so much oil associated with panel making; so can we reduce the process risk at site level, and do it proactively?’

“So that is what we do. The reality is that risk has to be made visible. So we work to pass on our knowledge to the people operating the press, those at the source of the risk, the site itself. We pass on our knowledge of risk to the customer and help him to know how to handle those risks. Actually supplying the oil is secondary to that, and we do not much mind whether he gets his oil from us or from someone else.”

The interest in these services has grown hugely in recent years, especially in the US, says the MD.

“In Europe, as I have said, it was new regulations that sparked the growth. In the US, it is partly led by insurance companies. In the decade to 1989, the largest US insurers in the panel industry recorded 54 ‘losses’ – in other words, a major incident roughly every two months. Between 1990 and 2008 it stayed at around that level – so we are talking of costs of hundreds of millions of dollars.

“But since the 2008 financial collapse there has been another cause. Dozens of mills were mothballed then. Now owners are looking at restarting them. But since they have been gathering dust for a decade, restarting involves more than just turning the key. Upgrading, rethinking and redesigning procedures is necessary.”

Insurance companies are concerned with infrastructure. “We work more with the systems – how they work at site level – to understand the root causes of a hazard and to put them right. For example, a refractory failure in a heater would show up in a lab sample; if an over-temperature alarm goes off, what does that mean and what should the operator do apart from hit an off-button switch? The combination of our experts, the operator’s on-site expertise, and passing our knowledge on to the operators is what counts.

Regulations now require operators to take ownership of risks. If they do not understand the risks, they are understandably afraid of doing that.

“That is where we step in.”

The opening of new plants, and the reopening of old ones, mean that Thermal Oil Solution’s North American subsidiary is likely to be kept very busy.