Cyclone cures cold run engine pollution

A small device fitted to car exhausts may be sufficient to greatly reduce pollution problems caused by cold running engines just started up. Tom Shelley reports A retired doctor has invented a small cyclone, which he believes, will greatly reduce air pollution problems caused by initially cold engines and exhaust systems that have just been started up. Even the most uneducated observer will notice drops of liquid and visible fumes emerging from the tail pipe of a just started car, and it has been strongly suggested, that along with substances that can't be seen, such emissions are hazardous for both humans and animals. Dr Grahame Henley, who practised in Bristol, but now lives in Axminster, is convinced that the unpleasantness of these emissions is enhanced by the recent popularity of introducing detergents not only into lubricating oils but also into petrol, in order to prevent the build up of carbon within the engine. He believes that what initially comes out of the tail pipe is a mixture of oil and water, stabilised by detergent. We have tried to check this out with suitably knowledgeable chemists, but all we have consulted have either declined to give any opinion, or given conflicting opinions, emphasising that they did not wish to be quoted for fear of arousing the wrath of oil companies. The opinions given varied all the way from considering that the detergent additives have no effect, to an opinion that they are likely to be oxidised to aldehydes by the catalyst, which are definitely bad for you. One expressed concerned about particulates, especially from diesel engines, which he believed were laced with small quantities of carcinogens derived from the lubricating oil. Either way, what comes out of an engine exhaust pipe when the engine is started up may be very bad. European Union legislation is definitely in the offing. We are aware of developments to pre-heat engines and pre-heat converters, but if Dr Henley's cyclone does the job, it would be a lot cheaper. He has conducted some experiments, sufficient to show that the basic idea works. In his design, it was mounted on its side, with gas injected tangentially at the wide end from the top, exiting through a pipe inserted through the narrow end. Fluid and detritus was found to accumulate at the wide end below the entry point. The wide end in his prototype was removable to allow examination of contents. He proposes that the cyclone should contain some kind of absorbing medium, either disposable, or ceramic in the hope that noxious substances would be burned away when it became hot. He says that the volume of the cyclone should approximately equal the engine cubic capacity. He has applied for a patent. Pointers * A small cyclone attached to an engine exhaust tail pipe looks to be a possible way to greatly reduce emissions of fluids and particulates, especially when the engine and catalytic converters are cold when the engine has just been started * It can be mounted on its side and should be of similar volume to the engine cubic capacity