The filtration of public water-supplies / Third edition, revised and enlarged.
General View of Filters at Hamburg.
MEMBER OF THE AMERICAN SOCIETY OF CIVIL ENGINEERS, THE BOSTON SOCIETY OF CIVIL ENGINEERS, THE AMERICAN WATER-WORKS ASSOCIATION, THE NEW ENGLAND WATER-WORKS ASSOCIATION, THE AMERICAN CHEMICAL SOCIETY, THE AMERICAN PUBLIC HEALTH ASSOCIATION, ETC.
THIRD EDITION, REVISED AND ENLARGED. SECOND THOUSAND.
NEW YORK: JOHN WILEY & SONS. London: CHAPMAN & HALL, Limited. 1905.
Copyright, 1900, BY ALLEN HAZEN.
ROBERT DRUMMOND, ELECTROTYPER AND PRINTER, NEW YORK.
The subject of water-filtration is commencing to receive a great deal of attention in the United States. The more densely populated European countries were forced to adopt filtration many years ago, to prevent the evils arising from the unavoidable contaminations of the rivers and lakes which were the only available sources for their public water-supplies; and it has been found to answer its purpose so well that at the present time cities in Europe nearly if not quite equal in population to all the cities of the United States are supplied with filtered water.
Many years ago, when the whole subject of water-supply was still comparatively new in this country, filtration was considered as a means for rendering the waters of our rivers suitable for the purpose of domestic water-supply. St. Louis investigated this subject in 1866, and the engineer of the St. Louis Water Board, the late Mr. J. P. Kirkwood, made an investigation and report upon European methods of filtration which was published in 1869, and was such a model of full and accurate statement combined with clearly-drawn conclusions that, up to the present time, it has remained the only treatise upon the subject in English, notwithstanding the great advances which have been made, particularly in the last ten years, with the aid of knowledge of the bacteria and the germs of certain diseases in water.
Unfortunately the interest in the subject was not maintained in America, but was allowed to lag for many years; it was cheaper to use the water in its raw state than it was to purify it; the people became indifferent to the danger of such use, and the disastrous epidemics of cholera and typhoid fever, as well as of minor diseases, which so often resulted from the use of polluted water, were attributed to other causes. With increasing study and diffusion of knowledge the relations of water and disease are becoming better known, and the present state of things will not be allowed to continue; indeed at present there is inquiry at every hand as to the methods of improving waters.
Allen Hazen
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PREFACE TO FIRST EDITION.
PREFACE TO THIRD EDITION.
CONTENTS.
UNITS EMPLOYED.
ACKNOWLEDGMENT.
SEDIMENTATION-BASINS.
SIZE OF FILTER-BEDS.
FORM OF FILTER-BEDS.
COVERS FOR FILTERS.
SAND.
SANDS USED IN EUROPEAN FILTERS.
EFFECT OF SIZE OF GRAIN UPON EFFICIENCY OF FILTRATION.
EFFECT OF GRAIN SIZE UPON FREQUENCY OF SCRAPING.
SELECTION OF SAND.
THICKNESS OF THE SAND LAYER.
UNDERDRAINING.
GRAVEL LAYERS.
UNDERDRAINS.
DEPTH OF WATER ON THE FILTERS.
EFFECT OF RATE UPON COST OF FILTRATION.
EFFECT OF RATE UPON EFFICIENCY OF FILTRATION.
THE LOSS OF HEAD.
REGULATION OF THE RATE AND LOSS OF HEAD IN THE OLDER FILTERS.
APPARATUS FOR REGULATING THE RATE AND LOSS of HEAD.
APPARATUS FOR REGULATING THE RATE DIRECTLY.
APPARATUS FOR REGULATING THE HEIGHT OF WATER UPON FILTERS.
LIMIT TO THE LOSS OF HEAD.
FREQUENCY OF SCRAPING.
QUANTITY OF SAND TO BE REMOVED.
WASTING THE EFFLUENTS AFTER SCRAPING.
SAND-WASHING.
BACTERIAL EXAMINATION OF WATERS.
THE LAWRENCE FILTER.
CHEMNITZ WATER-WORKS.
APPLICATION OF INTERMITTENT FILTRATION.
THE MEASUREMENT OF COLOR.
AMOUNT OF COLOR IN AMERICAN WATERS.
REMOVAL OF COLOR.
MEASUREMENT OF TURBIDITY.
RELATION OF PLATINUM-WIRE TURBIDITIES TO SUSPENDED MATTERS.
SOURCE OF TURBIDITY.
THE AMOUNTS OF SUSPENDED MATTERS IN WATER.
PRELIMINARY PROCESSES TO REMOVE MUD.
EFFECT OF MUD UPON SAND FILTERS.
EFFECT OF TURBIDITY UPON THE LENGTH OF PERIOD.
POWER OF SAND FILTERS TO PRODUCE CLEAR EFFLUENTS FROM MUDDY WATER.
EFFECT OF MUD UPON BACTERIAL EFFICIENCY OF FILTERS.
LIMITS TO THE USE OF SUBSIDENCE FOR THE PRELIMINARY TREATMENT OF MUDDY WATERS.
SUBSTANCES USED FOR COAGULATION.
COAGULANTS WHICH HAVE BEEN USED.
AMOUNT OF COAGULANT REQUIRED TO REMOVE TURBIDITY.
AMOUNT OF COAGULANT REQUIRED TO REMOVE COLOR.
SUCCESSIVE APPLICATION OF COAGULANT.
THE AMOUNT OF COAGULANT WHICH VARIOUS WATERS WILL RECEIVE.
WASTING EFFLUENT AFTER WASHING FILTERS.
INFLUENCE OF AMOUNT OF SULPHATE OF ALUMINA ON BACTERIAL EFFICIENCY OF MECHANICAL FILTERS.
INFLUENCE OF DEGREE OF TURBIDITY UPON BACTERIAL EFFICIENCY OF MECHANICAL FILTERS.
AVERAGE RESULTS OBTAINED WITH VARIOUS QUANTITIES OF SULPHATE OF ALUMINA.
TYPES OF MECHANICAL FILTERS.
EFFICIENCY OF MECHANICAL FILTERS.
PRESSURE FILTERS.
WORMS TILE SYSTEM.
THE USE OF ASBESTOS.
FILTERS USING HIGH RATES OF FILTRATION WITHOUT COAGULANTS.
HOUSEHOLD FILTERS.
AMOUNT OF IRON REQUIRED TO RENDER WATER OBJECTIONABLE.
CAUSE OF IRON IN GROUND-WATERS.
TREATMENT OF IRON-CONTAINING WATERS.
IRON-REMOVAL PLANTS IN OPERATION.
COST OF FILTRATION.
WHAT WATERS REQUIRE FILTRATION?
NOTES REGARDING SAND FILTERS IN THE UNITED STATES.
CAPACITY OF FILTERS.
THE USE OF UNFILTERED SURFACE-WATERS.
DESCRIPTION OF PLANT.
CAPACITY OF PLANT AND MEANS OF REGULATION.
RESULTS OF OPERATION.
COST OF CONSTRUCTION.
FOOTNOTES:
INDEX.
