WATER WORKS MACHINERY AND DEVICES*
More than four-fifths of all the water plants of the State of Indiana belong to the smaller classes whose daily pumpages probably average less than one million gallons. As compared with the larger systems, these enterprises have relatively few consumers, limited revenues, and proportionately much higher fixed charges and operating expenditures. Therefore, it is easy to realize that the problems confronting such utilities as related to economy and efficiency are of paramount concern. And the smaller the utility, all the greater becomes the necessity for the closest scrutiny into its plant operations for the detection and stoppage of waste, and for the economical conduct of its affairs generally. Any discussion of topics, therefore, looking toward decreasing the operating expenses or of increasing the efficiency of these smaller enterprises, would seem to be especially appropriate in gatherings of this character, representing as it does so many of the plants of this class from all parts of the state. Every waterworks manager or superintendent among us has valuable property, involving large outlays of money, committed to his care. Upon hun, more than upon any other, devolves the double responsibility of rendering the best possible service to his patrons, and at the same time of permitting the least possible waste or loss to his concern, no matter whether privately or municipally owned. Realizing such responsibility the alert manager will profit, not alone by his own experience, but by all the knowledge and experience of others that is possible for him to acquire and bring to his aid in the everyday prosecution of his work. Hence are we all here for an exchange of ideas, and while to the larger operators present the suggestions herein made will doubtless appear as but the a, b, c’s of the waterworks business, if they contain any helpful word to a fellow-worker in the smaller ranks, the writer will consider his effort not wholly in vain.
A visit to almost any of the larger plants of the state will disclose the fact that they are not only equipped with all sorts of devices and facilities for the economical conduct of their enterprises, but will convince us also that they have experienced and technically trained men to manage and supervise them as well. Many of the smaller concerns likewise exemplify a similar degree of thrift and skill. To any of us, a detailed study of these systems and of their various kinds of operations for plant economy would be well worth while, and would doubtless yield abundantly in returns if the information thus acquired were adapted and applied, so far as practicable, to our own needs. So many and varied are the equipments available now-a-days which make for economy that to undertake a minute enumeration and description of them all would much overstep the requirements of this report, not to mention the writer’s lack of knowledge as to so wide a range. Only a few items, therefore, will be here considered, chief of which may be cited the pumping machine. As illustrating an experience in pumping economy you will permit me to state the conditions as existing in our plant at Valparaiso, and to make a comparison of the costs of operating each of our three different types of pumps. Our pumpage approximates one million gallons per day, pumping direct against a total bead of 85 feet. Our principal pump for continuous operations is a cross-compound, condensing engine, with Meyer gear and attached air pumps. Upon acceptance test when we purchased this machine two years ago it showed a duty of 78.57 million foot pounds per 1,000 pounds of steam used, pumptng against our usual head at normal load. Assuming an apparent evaporation of seven pounds of water to each pound of coal, and a total head of 100 feet, with a working duty of about seventy million foot pounds per 1,000 pounds of steam, this machine will pump and deliver one million gallons of water each day for one month at a steam consumption of 358,071 pounds, thus requiring 25.57 tons of coal, which at 63.50 per ton in bin, costs us $80.40. With our No. 2 reserve pump, of the non-compound, condensing, crank and fly-wheel type, assuming a working duty of only fifty million foot pounds, which really is a trifle too high, for the same pumping operation, 501,300 pounds of steam would be consumed, requiring 35.80 tons of coal at a cost of $124.30. With our third unit, a simple duplex pump, which needless to state is rarely placed in service, 752,128 pounds of steam would be used, or 53.71 tons of coal costing us $187.98.
Thus it is observed that by using our No. 1 pump, for each month we operate we show a saving of $34.81 over pump No. 2, while over pump No. 3 we effect a saving of $98.49, or in round numbers at the rate of almost $l,200.00 per year. Such a saving to any small plant in a comparatively short time would be sufficient to buy and install the very best and most economical type of pump which the market affords. In our own case it is plainly apparent that from the standpoint of even ordinary business economy we had better consign both of our low duty pumps to the scrappile rather than place them in continuous operation. As auxiliary units, for temporary emergency purposes, however, they of course have their proper place and value. A good, durable, dependable and economical pump for the particular service required, is the very heart of every waterworks system, and no plant can reach its highest state of efficiency unless its pumping equipment combines all of these fundamental requirements. The pumping machine for every plant should be designed so as to give the best possible economy at the normal load, but with ample capacity for the maximum requirements, such as the sudden opening of large connections, or where direct fire pressure is furnished at the hydrant nozzle. In most all cases operating economy should be considered in making a selection rather than first cost. But the fixed charges on a high duty machine of the Corliss type, by reason of its higher first cost, the greater housing space required and its many complications, may sometimes more than counterbalance the saving over a simpler type, such as the Meyer gear. While as heretofore noted, much saving may be effected by the use of properly designed pumping machines, likewise is the same degree of economy applicable to the boiler room. The kind of boilers, the character of fuel, and methods of firing are allimportant questions in considering boiler room, economies. For every plant the boilers should be in duplicate units, and like the pumps, of ample capacity for the peak load, though not too large for the normal uses. As safeguards, the steam lines from the boilers to each pumping unit should be as nearly separate as possible. Obviously also should the boiler feedwater systems be entirely separate and independent.
In determining the kind of coal to be used it has been our experience that dependence should not be placed upon the basis of heat units alone, but that the coals should be tried out, not merely for a few days under the most favorable firing conditions, but thoroughly tested under the every-day working conditions just as they actually exist. Under such test, the coal evaporating the most water for the dollar manifestly should be the kind to adopt. Moreover, with propriety, and sometimes with profit as well, coal bought on contract may be tested from time to time as a check upon its continued good quality. For this purpose where the amount consumed will not warrant the purchase of a good bomb calorimeter, the lead oxide reduction method may be used, such an outfit costing but a few dollars and the results being sufficiently satisfactory for purposes of comparison. Where the coal storage room is located adjacent to railroad siding, if used in quantities sufficient to justify, coal conveying machinery may effect a substantial saving over the usual hand operations. With good boilers, the right kind of pumping machines and the best kind of coal in stock for the purpose, there yet remains the continuous, all-important, every-day question of operations, of tueling, and ol so conserving the fuel energy stored away in the coal as to utilize and transmit the same direct to the engine throttle in quanities as needed, rather than as we too often observe, carried up the smokestack only to be “wasted on the desert air.” Fuel conservation is one of the most difficult of all perplexing questions confronting every power plant. Even the most careful firemen need every practicable facility with which we can surround them if the highest results are to be continuously maintained.
As aids in this work, involving as it does one of the most conspicuous items in operating costs, the best patterns of shaker and dumping grates, and also automatic damper regulators, may be used with profit. If the amount of coal consumed will not justify the purchase of a CO2 recorder, a boiler efficiency meter with Orsat apparatus will be found to furnish a valuable guide. Steam flow meters may be had at small cost for attachment to the different steam lines, and when installed will furnish desirable information as to the amount of steam conveyed to the different units or heating systems. Another device of value though of much greater cost, is the Venturi meter, which if placed on the pump discharge line as a check on the engine counter, will often reveal unsuspected pump slippages needing correction. A common and often unconsidered source of loss in many small plants is leaky valves. A valve reseating machine should be in every power house and by its use every valve kept always in proper repair. Suitable equipments for the various repairs common to all plants from time to time are not only necessary but money-saving assets in times of their need. Oiling arrangements frequently are not given the attention which their importance would seem to deserve. The system employed should be such that the oils may be saved, refiltered and used again. With such saving they may be used more freely than otherwise, thus safeguarding against hot bear.ngs from time to time, with their consequent annoyance, or possible interruption to the service. In connection with the operation with filtration systems a good serviceable laboratory would seem to be indispensable for the necessary tests. Cities without such systems and having water at times of questionable quality will find apparatus for the use of hypochlorite of lime to be an inexpensive as well as most valuable acquisition. By the use of steam and water pressure recording gauges, if supplemented with accurate hourly notations of coal consumed and water pumped, the engineer and manager are afforded definite knowledge concerning the workings of the plant, and also furnished a permanent record of the same.
So well known is the value of the water meter that it would seem to be superfluous to make mention of it here. And yet the fact remains that in Indiana there are a number of plants operating almost, if not entirely, upon flat-rate bases. As a conserver of water this device is second to none, and its value is closely followed by the meter testing machine. For leakage inspections the detectorphone and pitometer are both widely recommended. For the office there are many devices worthy of adoption and use, such as the adding machine, the typewriter, addressograph, card indexes, filing apparatus, looseleaf systems, etc. An accurate map showing definitely the location of all mains, valves and service boxes is of inestimable value and should be deemed an indispensable part of every system. A few well-selected technical books and the best waterworks journals will prove to be not only sources of information and pleasure but of actual profit as well. For articles of especial interest, should one wish to dispense with indexes, a scrap-book might be used to good purpose. In concluding, no word of mine is needed to remind the managers of these smaller utilities that theirs is a worthy task to perform, none the less because of their limited fields. To supply our fellow-beings with good water is a distinct service to mankind. Next to the air we breathe water is the sustaining power of life. Not meagrely, therefore, should we provide this necessity to our communities, but abundantly and constantly, with a good, clear, clean and wholesome water of unquestionable quality. Moreover, the returns from such service should justify the very best plant that is possible to be had, for upon no other enterprise is any municipality so dependent for its healthfulness and prosperity. Without extravagance or display, every water system should be a model system, and any machine or device making either for economy, efficiency or continuity of operations should not be withheld or denied. Little for elaboration; much for economy; everything for quality and service, therefore, would the writer urge as the business policy, the continual watchwords and slogan of every waterworks man.
(*Paper read before the Indiana Sanitary and Water Supply Association, at Indianapolis, February 26, 1014, by E. L. Loomis, Superintendent Valparaiso Home Water Co.)