SCIENTIFIC TESTS OF WEBB SEWER LAMPS

1893-4

Back

LABORATORY AND ASSAY OFFICE,

37 PARADISE STREET,

BIRMINGHAM,

October, 1893.

SIRS,

I hereby Certify that I have examined the Sewer Gas Destructor,  erected by you at Hockley, where every facility was afforded me for testing  the apparatus, and I have to Report as follows :—

1. The apparatus is full-sized, and is working under perfectly practical conditions.

2. It is a combination of a Street Lamp and an Extractor, in which the  lighting and destructing power of the gas are both utilized.

3. The rate of extraction of sewer gas when the burner is passing 15 cubic feet per hour averages 580 cubic feet per hour, and this quantity is drawn over  a length of some 450 yards of sewer.

4. The nauseous character of the sewer gas entering the Destructor is most marked. The whole of this gas is subjected to a temperature of  650-700 Fahrenheit when the Destructor is in full work, and no smell whatever beyond that of ordinary burnt gas is perceptible on the top of the Destructor.

5. At the temperature obtained I regard the existence of any disease germs  or nauseous organic bodies in the gases leaving the apparatus as  impossible

6. I made careful photometric measurement of the effect of the sewer gas on the luminosity of the flame, and I found in every experiment a  distinct increase when the sewer gas was being consumed. The  actual increase varied considerably in accordance with the condition  of the sewer and the prevailing wind, etc., but I should consider the  increase was at least 5 percent above the normal, that was when  the gas was burning in ordinary air.

From these results, I conclude that the system is one of very  considerable importance, its efficiency is certainly very high and its utility  would appear to be of very wide application.

Faithfully yours,

ALEX. E. TUCKER, F.I.C.,  (Consulting Chemist)

NOTE.—The Destructor which Mr. A. E. Tucker experimented with was fixed to a 6 in. drain, laid to  the building line and connected to the main sewer, ll ft. 6in. deep, by the Corporation of Birmingham, and the  whole of the other parts under their supervision and tested by them. The length of drain from Destructor to  main sewer is 130ft., and the gradient is only ¼ in. per foot. The height of Destructor outlet is 12 ft. above the  level of the street, and it is therefore working under disadvantages which would never occur in ordinary  street lighting, where it would be placed near the sewer and the drain leading to it, only shorter and of a  much steeper gradient, thus adding to the results it has already obtained.

SINCE the testing of our system for the extraction and destruction of Sewer Gas by Mr. A. E. TUCKER, as recorded above,  we have, as the result of careful study of details and of experiment, made considerable improvements, and being determined  to subject our Destructor to the severest practical tests possible or obtainable, we approached the Tottenham Local Board,  whose sewers, we were informed in some places, were most foul with sewer gas. The Board accepted our offer to erect two  Destructors, and the Sanitary Committee of the Board with its Engineer carefully selected two sites, where, judging from the reports  of their own Officials, given in consequence of Memorials against the prevalence of foul smells in the roads made by residents in the  immediate vicinity, they knew the sewer gas exhalations to be highly noxious and dangerous. These two sites were undoubtedly  the worst in Tottenham.

THE ST. ANN’S ROAD DESTRUCTOR.— This was, on July 19th 1894, fixed on a “Refuge” taking the place of a Sugg’s 3-light Burner  consuming 18 cubit feet of coal gas per hour. The “Refuge” is at the foot of a hill and the Destructor is connected with the sewer which  is 8 feet below the road surface, and 2 feet 6 inches by 1 foot 9 inches in size. Fifty yards away, the sewer is syphoned under the  Water Main of the New River Company, and all the surrounding air inlets were stopped by order of the Board’s Engineer, whose  men made all the necessary connections. The nearest known inlet is 250 yards away, At the first test of this Destructor, when  completed, our Mr. J. E. Webb, (who is the inventor of the system), had his thermometer burst at 800 degrees Fahrenheit, and his  anemometer showed at times an extraction of air from the sewer equal to 2,000 cubic feet per hour. This was in the presence of  several members of the Local Board, who also noted that at the outlet of the Destructor, the emitted hot air gave no sign of smell  but readily ignited hemp joint yarn held above it, and that the light too, given by the 15 cubic feet of coal gas as against the 18 cubic feet in the  deposed Sugg lamp was actually better than before, newspaper type being read at a distance of 50 yards. On July 30 (the air inlets  having been closed all the time and the Destructor being generally unlit during the day time), the man hole was opened, and as testified to by Mr. Messum in the report given below, the sewer was found to be perfectly free from smell, a strong contrast to  previous times when it exhaled Carburetted Hydrogen and Carbonic Acid Gas.

THE LORDSHIP LANE DESTRUCTOR.— The Site of this Destructor, which was fixed on July 25 1894, is on the rise of a hill. The  sewer operated upon is the Main Sewer leading from Wood Green to the Pumping Station, where the Tottenham Sewage is lifted  into the Metropolitan Main Drain. The sewer at this point is over 30 feet below the road surface and is 3 feet by 2 feet  inches.  Here, as at St. Ann’s Road, all known air inlets were closed and the connections made by the Boards men. This Destructor deals  with a sewer in which Sulphuretted Hydrogen largely prevails, and its effectivity is most abundantly proved by the thick deposit of  the waste products of combustion on the pneumatic radiator of the Destructor, and also by the absence of the sickly smell which on  previous occasions at this spot has caused people to faint in the roadway. The light of the Destructor is very brilliant, and the hot  air emitted is quite free from smell or taint.  

On July 30th 1894, the District Surveyor, on behalf of the Local Board, commenced his official tests of the two Destructors, and though not  yet completed, his advance statement to his Board, as subjoined, sufficiently indicates that our System as applied at Tottenham is a practical success. We claim that the coal gas now used for ordinary street lighting can without any increased consumption be utilized  also at the same time to effectually extract and cremate all gas generated in the sewers ; a small Destructor burning 6 cubic feet per hour  of coal gas, being capable of keeping up a temperature of at least 240 Fahrenheit, a heat sufficient to destroy all germs of disease in a  length of sewer 900 feet linear by 15 inches diameter.

EXTRACT FROM A TOTTENHAM LOCAL PAPER OF FRIDAY AUGUST 3RD 1894

“TQTTENHAM LOCAL BOARD.— A meeting of this Board took place on Wednesday evening last at Coombes Croft House,  Mr. E. P. Huggett in the chair. The members present were :St. Ann's: B. Goodwin, J. Messum. High Cross: F. Jenkins,  W. E. Barrett, R. H. Matthews. West Green: W. Jubb. P. B. Malone. Middle Ward : A. Campion, W. Peart, C. W. Bradshaw.  Lower: J. Cloudsley, W. Brown. Absent: A. A. Robinson and W. Low.

SEWER GAS  DESTRUCTORS.

Mr. Bradshaw asked the Engineer if he had tested the sewer gas destructors that had been erected. The Engineer said he had made  one test of each destructor the previous day and that day, and the average temperature was 550, while the average extraction of sewer  gas was about 1,300 cubic feet per hour. Mr. Messum said that, previous to the Destructor being erected in St. Ann's, those in the immediate neighbourhood could hardly stay in their houses as the stench was so abominable, but since it had been erected they had  had no smell whatever, and more than this, on Tuesday the manhole of the main sewer was opened, and he knelt down and put his  head over it, and it was perfectly free from smell. The Engineer further stated that he was going to continue the tests under all conditions of the atmosphere, and when he had concluded those tests he would submit his report to the Board.”

Note: These two have been purchased by the Tottenham Council after nine months trial.