Actually, there are lots of problems with heavy fuel oil blending.
According to a report two years back 13.7% of fuels failed to meet the ISO 8217 standard and the problem is alleged to be getting worse. I would gues there are going to be some high profile court cases soon when the MARPOL enforcers get tough with ships burning fuel with too much sulphur and the problem is oten with the fuel supplied.
The problem with "black product" is the lack of money in it. The question is always "is it more profitable to turn this stuff into fuel oil or bitumen?" or reprocess it into distillates?
It means that very little money is spent on fuel systems outside of refineries and little on system upgrades in the refineries.
By quality I don't refer to the fact that the actual fuel is worse (it is beacuse more refinery processes affect the residue quality), but that it is not blended to specifications (which it is not) and that is what the 13.7% figure refers to.
Also, even when accurately blended some are not properly mixed. It isn't just compatability problems its that just putting two components into the same pipeline does mena they will mix. In an example quoted somewhere, reservoir water and well water were "mixed" in a large bore pipline. 500ft downstream they were still identifiable as separate flow streams from their hardness values.
But TD2K is right, a good meter blenders will include a jet mixer or a static mixer and will produce a good mix and if you use viscosity trim control and know the component qualities accurately enough to calculate the blend properties or you sample the blend representatively and have it analysed, there is absolutely no reason why you shouldn't get a good accurate well mixed blend that is stable and meets the specifications.
Apshalt blending has had another problem, more money invested and better care taken but limited suitable online viscometers. Though again, more modern viscometers are being used for online trim control.
JMW
