Battersea Power Station Research Articles

Expanded tube joints in boiler drums, with special reference to the battersea high-pressure boilers

Particulars are given of the major pressure parts of two high-pressure boilers installed at Battersea Power Station, each comprising four alloy steel drums and their interconnecting mild steel tubing. Their design and working conditions are described, and a historical review is presented of their erection and of problems which arose whilst rendering the expanded tube joints leakproof. The gradual resolution of these problems is then traced through several stages. It was realized that the leakage was fundamentally due to the elastic strain which occurs in the tube holes of highly stressed drums, which, at Battersea, amounts to about twice that pertaining to mild steel drums. The holding power of the joint is thus relaxed to an abnormal extent, sufficient to permit leakage. The elastic deflexions, or total “spring” of the joint, resulting from the expanding operation, must therefore be correspondingly increased to accommodate the increased drum strain.Various suggested methods of achieving this are reviewed...

The Battersea Power Station

THE annual report of the Electricity Commissioners (London: H.M. Stationery Office) giving the returns of fuel consumption and electric units generated in Great Britain shows that the total quantity of electricity generated during 1936 was 14 per cent more than during the preceding year. The annual fuel consumption was 1–57 Ib. per electric unit distributed. The steam station with the highest thermal efficiency, 27· 63 per cent, is Battersea (London Power Company) and the station with the highest load, 208,000 kilowatts, is Barking A (County of London). The London Power Co. is extending its station at a cost of £1,500,000. The work constitutes the beginning of the second half of the station and includes the extension of the building to double its present size and the installation of 100,000 kw. of generating plant. This is the first instalment of the plant to be provided in the new building. It is expected that this, together with the 243,000 kw. plant already working, will meet the probable demands for electricity up to the winter 1939-40. Eventually the generating capacity is to be raised to 500,000 kw. The new plant comprises a high-pressure set, a low-pressure set and a house set. The high-pressure set generates 16,000 kw., the low-pressure set 78,000 kw. and the house set 6,000 kw. The new plant also includes one boiler of 550,000 Ib. evaporative capacity. Londoners will watch the development of this huge power station with interest. Practice has justified the policy of fostering the efficient stations in Great Britain. The returns show that whilst there were 458 generating stations in 1935, there were only 442 in 1936.

The New Fulham Electrical Power Station

THE new power station at Fulham on the banks of the Thames was opened formally on September 26. It occupies an area of 15 acres and has a river frontage of 1,300 feet. It is an extension of the existing plant of the Metropolitan Borough of Fulham, but the disparity between its size and the demand required for the borough shows that the new station is an undertaking to serve the Grid. Two sets of 60,000 kilowatts:each were installed this year and a third set is now being added. The boiler house is at right angles to the river and the turbine room is parallel to the river. Two white reinforced concrete chimneys three hundred feet high are already built, and when the Station is completed there will be four of them. Three colliers have been ordered, each of them capable of carrying 2,300 tons of coal, and the jetty has three travelling cranes each capable of handling -175 tons an hour. The cranes pass the coal to weighing machines, whence it is fed to the furnaces on two belt conveyors which run at 300 feet per minute. Using only two cranes enables a collier to be unloaded in 6| hours. When complete and working at approximately half its maximum power, the station will consume roughly 2,000 tons of coal per day. The final fleet of colliers will consist of six boats capable of sea voyages and of passing under the seventeen bridges up the River Thames to Fulham. The new station has a dignified appearance and in conjunction with the Battersea power station on the opposite bank of the Thames will enable the Central Electricity Board to balance the London load.

Removal of Smoke and Acid Constituents from Flue Gases

PRACTICAL remedies for preventing or reducing the emission of objectionable constituents in flue gases have in the past been mainly confined to the elimination of grit and dust emission. In large urban areas it is now realised that the acid emission is attended with more serious consequences. In 1927, Parliamentary sanction was only given to the erection of Battersea Power Station on the condition that the best practicable means should be taken to remove the oxides of sulphur from the flue gases. In a paper on a new method of removing smoke and acid constituents from flue gases read on January 7 to a joint meeting of the Institute of Fuel and the Institution of Electrical Engineers by Dr. J. L. Pearson, G. Nonhebel and P. H. N. Ulander, it was stated that the daily combustion of 1,000 tons of average coal in addition to grit, dust and tarry matter, leads to the formation of 45 tons of sulphuric acid, 3–7 tons of nitric acid and half a ton of hydrochloric acid. It is clear that when wet washing is applied, a non-effluent system must be used. The new system is a recirculating, non-effluent water system, from which the grit, dust and ashes are separated and removed as solids. A pilot plant was erected at Billingham, and was subjected to a twenty-months' running test. The water used was a hard surface water drawn from a local stream. Lime was used as the alkali for most of the test, and chalk was used for the remainder. Very satisfactory results were obtained. 97–99 per cent of the sulphur oxides were removed, 90–93 per cent of the hydrochloric acid and 97–98 per cent of the grit and dust from the pulverised fuel boiler. The exit gas from the plant is so free from sulphur dioxide that it is practically odourless, although the sense of smell can detect a very minute trace of this gas.

Electric Shut-Down in London

THE sudden cessation of the supply of electricity over London and part of the south-east of England during midday on July 29 proves that even with the best machinery a breakdown in the supply is a possibility that has to be guarded against. Luckily it is an extremely rare occurrence. The trouble started apparently when the engineers were re arranging sections of the supply at the Battersea power station. A small section becoming overloaded, the automatic circuit breaker came into action. When the circuit breaker was closed the currents in two of the sections were probably not in synchron ism and so a huge current circulated in the link connecting Battersea with the neighbouring station at Deptford West. The former had an output of 70,000 kilowatts at this moment and the latter of 90,000. The devices at Battersea declined to take the short circuit load, and several of the machines at Deptford shut down. The Barking Power Station had now to take the load, but the circuit breaker at Northfleet opened and the whole system ceased to operate. The effect was that the whole of the south-east area of the grid was suddenly deprived of 280,000 kilowatts of generating plant. The stations at Norwich and Brighton cleared themselves from the grid, the latter for about an hour. This affected the Southern Railway. The trouble was probably caused by the engineers taking advantage of the light load in summer to cut out certain transmission connexions for overhauling and so the grid system was not in full commission. It was not able to face the loss of Battersea, Barking and Deptford and still keep the whole system working. Notes on this shut-down are given in the Electrical Times of August 2.

A London Super Power Station

THE Battersea Power Station, which forms such a prominent landmark on the south side of the River Thames, will soon come into operation. It has been erected by the London Power Co., which was formed to secure the co-operation of the London electricity supply companies so as to reduce the cost by concentrating the generation of electricity in more efficient stations. It is one of the ‘selected’ stations adopted by the Central Electricity Board to supply the south-east of England electricity area. A description of it is given by I. V. Robinson in World Power for May. At present the station possesses two 70,000 kilowatt turbo-alternator sets and a 100,000 kw. set has been ordered. There are six Babcock and Wilcox boilers each evaporating 330,000 Ib. of steam per hour at a pressure of 650 Ib. per square inch and a temperature of 875° F. A jetty has been built parallel to the wharf which accommodates two of the company's 2,000–ton colliers at once. The coal is extracted by grabs and deposited on conveyors which take it to the boiler-house. Owing to the vicinity of the Houses of Parliament, Westminster Abbey, etc., it was necessary to take precautions so that the fumes would not act harmfully on these buildings. By means of induced draught fans the products of combustion are forced through ‘scrubbers’, passing across vertical surfaces in which water is flowing. They next pass over the main scrubbers consisting of cases of iron filings over which a stream of water flows. The iron acts as a catalyst converting SO2 into SO3. On reaching the chimney the gases first pass down a central chamber containing more steel sections and so have more oxide of sulphur abstracted. They then meet water containing alkaline salts which completes the purification. It is computed that 90–95 per cent of the oxide of sulphur has been eliminated.

Portraits at the Royal Academy

IN addition to the pictures at the Royal Academy mentioned by Dr. Vaughan Cornish in his article elsewhere in this issue, scientific workers will be interested in the following portraits: Prof. S. Alexander, honorary professor of philosophy in the University of Manchester, charcoal, by Francis Dodd (1212); Sir Richard Glazebrook, formerly director of the National Physical Laboratory, by Edward I. Halliday (390); Dr. George Francis Hill, director and principal librarian of the British Museum, bronze medallion by Frank Bowcher (1650); Prof. J. G. Lawn, mining engineer, director of and consulting engineer in England to the Johannesburg Consolidated Investment Co., Ltd., bronze bust by Maggie Mitchell (1736); Dr. Eleanor Lodge, formerly principal of Westfield College, London, by Gerald F. Kelly (91); Sir Murdoch Macdonald, president of the Institution of Civil Engineers, bronze bust by Gladys Barren (1725); Lord Melchett, director of Imperial Chemical Industries, Ltd., by Glyn Philpot (274); Dr. Alexander Scott, director of scientific research at the British Museum, head by Sir W. Reynolds-Stephens (1638); the late Sir William Smith, founder of the Royal Institute of Public Health, bust by Charles L. Hartwell (1602); and Sir J. J. Thomson, master of Trinity College, Cambridge, chalk, by W. T. Monnington (1180). Among the other exhibits are a tempera of the foundations of the new Geological Museum, South Kensington, by Laurence Wheatley (881); while the architectural drawings and models section includes the library of the same Museum, by John H. Markham (1405), proposed additions to the Ashmolean Museum, Oxford, by Stanley Hall, and Easton and Robertson (1400), the completion of wings to Gower Street of University College, London, by Richardson and Gill (1512); and an etching and dry point of Battersea Power Station, by H. R. Myerscough-Walker (1257).

Power Stations and Air Pollution

DURING the past two years, public attention in Great Britain has been focused on the question of air pollution due to the operation of super-power electric stations. In his recent presidential address to the Junior Institution of Engineers, Dr. S. L. Pearce, engineer-in-chief of the London Power Company, discusses this problem and others of great importance at the present time owing to the practice of concentrating more and more power in single generating stations. Efficient measures are available for preventing the pollution of the atmosphere by the smoke and ash from chimney-stacks when stoker-fired boilers are used, but when pulverised fuel is adopted the problem becomes more difficult, owing to the fineness of the dust content of the ash. The recent controversy about the new Battersea power station had reference to the much more difficult problem of arresting the possible damage to buildings and vegetation, and the alleged danger to life, due to the sulphur oxides contained in the products of combustion issuing from the chimneys.