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6-inch drain 9 inches acres aerating aerobic Albuminoid Albuminoid Ammonia Ammonia amount anaerobic organisms Anne Arundel County avenue average bacterial filters bacteriolytic Baltimore boilers bottom channel chemical Chesapeake Bay clinker coarse filters coke breeze construction cost crude sewage cube feet cubic feet depth diameter Dibdin filters discharge district mains dry weather flow Ducat's Eastern High-Level Interceptor Eastern Low-Level Interceptor estimated Eutaw Exeter feet 6 inches feet 9 feet per second filter beds filtered effluent filtering material filtrate gallons per day Glen Burnie gravel increased inlet installation large numbers layer Locust Point main sewer manhole Masonville micro-organisms Nitrates nitric acid Nitrogen organic matter outfall mains Outfall Sewer oxidation Oxygen absorbed oyster passed pipes polarite population Project L-M pumping station quantity river samples sand screen septic tank sewage effluent Sewerage Commission sewers siphon sludge submerged outlet surface tank effluent tion treatment Western Low-Level whilst
Popular passages
Page 103 - ... and nitric acids. In the soil these acids combine with the various basic substances, lime, magnesia and the like, are thus rapidly removed and the way is left clear for the formation of fresh batches of the same substances. In anaerobic putrefaction, on the other hand, the process does not go in this -unobtrusive fashion, the anaerobic organisms having as it were to wrest their oxygen from the organic molecules because there is no free oxygen present, set up a much greater disturbance and the...
Page 11 - IN /69T. numbers present in sewage. I need hardly refer to the fact that the typhoid bacillus has only in rare cases been found even in waters and sewages to which it must obviously have penetrated. This disappearance is clearly explained by some experiments of Dr. Sims Woodhead at Exeter, when he found that crude sewages containing about half a million organisms per cubic centimetre when inoculated into the filtered effluent of a septic tank developed more than one thousand millions in five days,...
Page 103 - ... essentially the same as those already described. In the process it is necessary (1) to get all solid matter into solution ; (2) to supply as large a quantity of oxygen in as short a time as possible to this organic matter ; (3) to attack the organic matter in solution by means of micro-organisms and to so break it up that the various elements of which this complex material is composed may be thrown into an unstable or nascent condition so that the oxygen present may have an opportunity of entering...
Page 9 - ... Their presence we must fear, but to restore a little confidence in the abused mollusc, I will quote some of Dr. Thome Thome's own words : " Only a few of the layings, fattening beds, or storage ponds round our coast can be regarded as theoretically free from every possible chance of sewage pollution. But, as regards the majority of them, any such polluting matter becomes mixed with so vast a bulk of water that it is difficult to see how the layings can be subjected to anything approaching substantial...
Page 102 - ... to obtain free oxygen, and have thus been compelled to develop the power of wresting oxygen by force, as it were, from the oxygen-containing bodies that come down to them from the surface, usually using part only of the combined oxygen, and setting free another part to be used up in the oxidation of portions of the organic matter that still remains. So completely do these organisms use up the food that has come from the surface, that at a depth of about twelve feet no microorganisms at all can...
Page 103 - ... place in two perfectly different ways. In the one case we have the oxidation taking place directly, all the nascent substances being satisfied by the oxygen of the air and the splitting up of the organic matter being carried on by aerobic organisms. In such a process of oxidation, which takes place in porous soil well supplied with air and moisture, and also in water which is from time to time well saturated with oxygen, it will be found that little or no putrefactive odour is developed. The...
Page 103 - ... place in the breaking down of organic matter in nature may also take place, under certain conditions, in artificiallyprepared filters. The main factors in the process are essentially the same as those already described. In the process it is necessary (1) to get all solid matter into solution ; (2) to supply as large a quantity of oxygen in as short a time as possible to this organic matter ; (3) to attack the organic matter in solution by means of micro-organisms and to so break it up that the...
Page 102 - ... the aerobic organisms, but it has still to run the gauntlet of the anaerobes. It is assumed that, having been washed deeper into the soil and living, as it were, at some distance from the atmosphere, these anaerobic organisms (originally aerobic) have been unable to obtain free oxygen, and have thus been compelled to develop the power of wresting oxygen by force, as it were, from the oxygen-containing bodies that come down to them from the surface, usually using part only of the combined oxygen,...
Page 12 - We may confidently expect, with the completion of a good sewerage system, the present (typhoid) death rate of Baltimore, about 40 per 100,000, to fall to that of the cities of the first class, from 4 to 8 per 100,000 inhabitants.