Check On Air Pollution

Press, Volume CVI, Issue 31345, 15 April 1967, Page 5

Check On Air Pollution

UNIQUE series of experiments conducted in Britain promises to be of fundamental importance in the world-wide campaign against air-pol-lution. The experiments were made into the behaviour of smoke from the chimneys of a typical industrial and residential town.

The experiments were conducted by scientists from the British Petroleum Company’s research centre at Sunbury and the “average town” they chose for their work was Reading, 40 miles west of London. The local authority, householders, industrial firms and fuel suppliers co-operated. As a supplier and user of fuels British Petroleum wanted to know the answers to a number of problems concerning smoke dispersal, notably toe heights to which industrial chimneys should be built Chimney Effluent Studies on toe dispersal of effluent from chimneys have been conducted many times before and equations have been prepared for calculating the dilution of effluents downwind. But for various reasons these equations have usually been developed for Isolated chimneys in flat surroundings, whereas most chimneys stand in industrial or urban areas. The whole subject is complicated by the fact that flue gas from a chimney is not only dependent upon toe wind strength and direction, and the change of air temperature with height, but also upon the local turbulence of the wind. Any wind vane shows how turbulent toe wind can be.

The experiments at Reading have been concerned with the behaviour of chimneys when they are surrounded by other industrial or domestic smoke stacks. When the findings have been analysed it should be possible to calculate the effect of one chimney in a background of pollution from other chimneys. Reading, roughly in the centre of England, has a population of 114,000. Its industry is varied, and includes biscuit - making, metal-working, brewing, seedgrowing, market gardening and printing. It is also a railway junction and there are the usual public utilities, such as electricity and gas-making plants. This combination of industrial and residential property with its assortment of

smoke-emitters of many heights and sizes proved an ideal environment for toe tests, which occupied 15 months.

Basically toe investigation was designed to find toe best method of predicting the concentration of pollution in various parts of toe town, knowing the weather and how the pollutants were emitted. No effort was made to increase or reduce toe normal day-to-day smoke emissions of the town. Air Samples Air samplers were placed at 40 sites around toe town to enable the sulphur dioxide content of toe air to be measured for six-hourly periods. The samples were analysed and meteorological observations were timed to coincide with toe sampling. To record air turbulence a light bivane was mounted on a 42 feet mast near the laboratory and toe movement was recorded on a chart Vertical variation of air temperature was measured with a radio sonde which could be lifted to 500 feet by a small kite balloon. The sonde was sent aloft four times daily, measuring toe air temperature at various heights so that the presence of inversion layers, which are very relevant to fog production, could be determined. Reading University also provided meteorological information. The other part of toe experiment involved a survey of the fuels used in the town, a task helped considerably by toe cooperation of industrial firms and fuel suppliers. These consumption figures will allow the Reading values of ground concentration to be scaled up or down to suit toe fuel burned in other towns and cities. They will also help distinguish toe effects produced by different kinds of fuel.

The mass of data accumulated at Reading includes some 85,000 measurements and these are being analysed —a time-consuming and expensive task for which digital computers are being used. The project has cost British Petroleum more than £60,000, and if this appears to be a lot of money to spend on a survey of smoking chimneys,

it should also be recognised that delays due to lack ol knowledge in the planning ol new industrial projects art also very costly. And the more that is known about the spread of gases from chim neys, the sooner will the

ri enormously wasteful effects of >f air pollution be brought in rf check. •e The verdict on Reading? By ie no means a dirty town. When le the higher concentrations n- were recorded, the wind ie was blowing from London.

Across s—The first of the scoundrels to pitch a tent is a rogue. (5) 8— Copes all right? No, copes all wrong! Hence the breakdown. (8) 9 Western ceremony put down on paper. (5) 10— Figured what all our days are! (8) 11— One letter, or the whole series if you place bet

afterwards. (5) 14—Some of toe men decline to come to a conclusion. (3) 16— Firm combination! (6) 17— The result of the golfer using a spoon? (6) 18— Frantic for mother’s return. (3) 20—Something for dessert

following the goose, maybe. (5) 24 It 14 Dn. Soothing baricjust toe material for the greasy pole! (8. 3) 25 One who gets up part of a step. (5) 26 Nine cast wrongly, for example. (8) 27 Signifies the way to an end. (5)

Down I—ls about to study figures " of worship. (5)

2—The leader of the club gets a member to go mountaineering. (5)

3 Celebrated and had a meal about morning. (5) 4 Like toe sea-bird at toe back. (6) 6 Those who are unconcerned couldn’t I (8) 7 This will be empty if people go on striking! (5-3) 12— Humble rank—that’s too place for one who is serving! (44) 13— A good man to encourage a fish. (8) 14— See 24 Across. 15— Two-way failure. (3) 19-r-Affected by ill-feeling. (6) 21— Ceases to come back—that’s rash! (5) 22 A mock assault in a cafe in Tehran. (5) 23 Power units. (5)