27 May 2001
New Zealand Refining Company General Manager, Alan Davey, said today that positive progress was being made to produce
and distribute new winter diesel stocks.
“As of yesterday, we began distributing new diesel stocks to the main ports. A tanker containing fresh diesel is on its
way south from the refinery right now. Our distribution programme will cover all ports over the coming weeks. With these
new stocks we should be able to clear the affected diesel within the next 30 days.”
Mr Davey said the advice continues to be that land-based diesel users should keep using current diesel stocks, as long
as they get fuel filters replaced at the first signs of clogging, and they use the advice given to date.
He said the new diesel stocks will initially be allocated on a priority basis. Emergency services and commercial marine
customers would be among the first to receive the fresh supplies and he expected some marine fuel stations which are
currently closed would have diesel stocks within the next few days.
Mr Davey appreciates this issue is causing anxiety and inconvenience. “The situation is regrettable and we are working
feverishly to resolve it.” He asks affected users to be patient during this time.
Anyone experiencing unusual or persistent performance problems such as rough running, loss of power or slow starting
should contact their diesel mechanic to see if they need a new filter. Engine damage is unlikely, but it is important to
seek advice as soon as symptoms develop.
A process for reimbursing costs incurred in replacing filters is being finalised over the next few days.
Diesel users needing further information should call the individual oil company’s help line listed below:
BP: 0800 800 027 (option 0)
Caltex: 0800 733 835
Mobil: 0800 808 666
Shell: 0800 474 355
Diesel backgrounder
What is diesel used for in New Zealand?
Diesel is used extensively for industrial, heavy vehicle and marine use. It is estimated that 15% of cars are powered
by diesel.
90% of diesel used comes from the Marsden Point Refinery, which produces 6 million litres of diesel per day. The same
base fuel is provided either directly or indirectly to all the oil companies except Gull.
What is the problem?
It appears to be related somehow to a winter use additive to diesel. The filters of some diesel engines are being
slowly blocked by diesel fuel containing this additive. Because the fuel must pass though the filter to get from the
tank into the engine, the effect is like running out of fuel - initial spluttering followed by stopping. The engine
should not be harmed in any way provided early action is taken when symptoms arise.
What about the supply of filters?
Filter manufacturers are being contacted to request additional supplies.
Why are additives used?
In colder winter temperatures diesel has a poorer flow. It is normal practice for additives to be added to improve the
flow. Three grades of diesel are produced during winter - a northern grade for the upper North Island, a central grade
and a southern South Island grade, and each may contain a different but probably higher concentration of additive in it.
The additive used is a long chain hydrocarbon or polymer. It is the only cold weather additive used at the refinery.
Is the additive the cause of the problem?
The problems co-incide with the use of the new additive but it is not clear yet what the cause of the problem is. It
could be:
- The way the additive was used at the refinery. It is delivered in bulk, but at the refinery it was diluted with
kerosene and then injected into the diesel blend
- The additive or the batch of additive supplied
- The crude oil stock being processed at the time
- The temperature and pressure at the time of injection
Why was the additive changed?
During the last year the Refining Company decided to review the additive it had used in the past and undertook
commercial and technical evaluation of a range of additives. New generation additives on the market were offering better
performance.
The type of additive chosen was one which has been used widely in the northern hemisphere in the past two years eg the
UK, Europe and the Americas. The additive was chosen after a competitive tender among five companies, shortlisting and
commercial and technical evaluation. Before release and use, the additive was subject to a wide range of tests in New
Zealand, none of which found any problems.
When did the problem emerge?
The additive was first used on 18 March 2001 with stocks likely to have been first used by customers in April. The use
of the additive ceased on Friday 24 May. The refining company heard the first reports of problems from oil companies two
days before, with unusually high levels of problems being reported by customers.
Why was this problem not detected?
All of the fuel blended during this time was tested and met all technical specifications that apply in New Zealand.
There is no standard industry test that can predict this kind of problem. The Refining Company has now developed a
filter test to check for these symptoms now and in the future.
How much diesel with this additive was produced?
Approximately 6-8 weeks’ worth, or 350 million litres.
What additive is being used now?
None at this time. Diesel is being manufactured in a different manner to ensure cold weather performance.
What is being done?
All diesel is now on grade and being fed into the supply chain as soon as possible.
The industry is looking to import diesel fuel that may be available overseas.
ENDS