A MODEL of a MODERN WATER FILTRATION PLANT as a PROJECT in HIGH-SCHOOL CHEMISTRY WILLIAM MAYROSE Senior High School, Muskegon, Michigan
A display model of a modern wterfiltration plant was built by a group of high-school chemistry students. The bluepi%nts used i n the construction of the actual plant were used in building the model, the scale being reduced such thut one-fourth of a n inch of the model equuled twelve inches of the actuul plant. Sections of the model
were covered with glass so that the inside of these sections could be studied. The pipe lines were represented by iron pipe, one-eighth of a n inch i n diameter, each line being painted a different color. The entire model was labeled at the appropriate places with typewritten labels describing the size of the real structure and the function of that part.
T
HE construction of a model of a modern water filtration plant was undertaken for two reasons: (1) the writer has felt for some time that models such as this would he ideal for the teaching of highschool chemistry, and (2) the project would stimulate the interest of three boys in the class in woodworking. I n addition to these three boys all students who volunteered were given some kind of work to do on the project. To obtain plans for the model a set of blueprints of the actual plant were obtained through the cooperation of the high-school principal. These were carefully studied and a simple general outline of the entire plant was made (Figure 1). While studying the blueprints
a number of questions were raised and noted concerning the details of the plant. Then the small group, who had volunteered, visited the plant and an inspection trip was made under the guidance of the chemist. Answers to the questions raised while studying the plans were obtained a t this time. During this trip the group was fortunate in being able to go into one of the underground settling basins, thus being able to inspect the construction of this basin and the mechanism within.
At the next meeting it was decided to make the model of such size that one-fourth of an inch of the model would equal twelve inches of the actual plant. It was also decided to construct the framework of the plant, then to decide how many details would be included. Accordingly, two boxes, 383/a inches by 7 inches by 2 3/s inches, were made to contain the filters, one box 47I/4 inches by 15 inches by 4a/4 inches to be two filtered water reservoirs, and one box 41 inches by 8 inches by 43/a inches to be one settling basin* were made. The head house, a two-story building containing the office, chlorinators, laboratory, and so forth, was made 20 inches by 15 inches by 12 inches. The work on the model was divided into three parts,
the head house, the filters, and the basins. A student was made chairman and placed in charge of the construction of each part. The other students who volunteered were assigned to help these chairmen. Journalism students in the class prepared accounts of the work for the school paper and also for the local daily newspaper. *The width of the basin and the reservoirs was not made to scale, since as much detail could be shown in a smaller size and also to keep the model from being too large.
Water for the city of Muskegon flows directly from Lake Michigan to a series of low lift pumps from where it is pumped to the head house. Here lime, alum, and charcoal are added through automatic dry feed machines. The water then goes to the rapid mixing chambers, two tanks nine and one-half feet square and nineteen feet deep. Apparatus to represent the dry feed machines was installed a t the proper place in the head house part of the model, as were structures to represent the mixing chambers. In addition to these, a room for the office with a desk and chair, one for the chemical laboratory with a chemistry table, and one for the chlorine room with its chlorinator were included.
FIGUEE2.-GENERAL VIEW OR TEE ENTIPIE MODELOR FILTR~TION PLANT
are huge paddle wheels and were made by gluing pieces of balsam in the form of a rectangle two inches by three inches with wire running diagonally for the cross pieces. A piece of plate glass covers eight inches of each end of the coagulation basin, to permit inspection of these structures, the remainder of the basin being covered with three-ply veneer. In the actual plant these basins are equipped with manholes for observing conditions inside the basins and with valves and outlets for cleaning. These were not shown in the model. From these basins the water flows to the filters. There are six filters, three on either side of an operating floor twenty feet wide. Each filter is 49 feet by 28 feet by Q1/* feet deep. Water is filtered through
THE
These were on the first floor. The second floor is used for the storage of chemicals. The dry feed machines are filled from hoppers on this floor. In the model this floor was made of plate glass so that the four feet of sand and gravel. The flow of water through arrangement of the 6rst floor could be more easily each filter, its cleaning, and so forth, is controlled from seen. Samples of lime, alum, and charcoal were dis- operating tables located on the operating floor. These played here. No roof was placed on the head house and operating tables were made of blocks of wood, painted one side was left out so that the structures inside could to illustrate the instruments and charts. To show the line carrying the settled water to the filters one-eighth be more easily inspected. The water is retained in the rapid mixing chambers inch iron pipe was used. This led into a piece of for three and one-half minutes after which it is sent t o grooved wood, painted gray, to represent a concrete the settling or coagulation basins. The model shows conduit which lies under the center of the operating by the use of iron pipe one-eighth of an inch in di- floor. From this conduit the water is carried to conameter, the lines carrying water from the mixing cham- duits dividing each filter in half and then to troughs running from this central structure to either end of the bers to the coagulation basins. These coagulation basins are huge underground filter. Water overflows these troughs filling the filter. tanks, one hundred sixty-four feet long, fifty-four feet These troughs were shown by grooved wood made to wide, and nineteen feet deep. There are two such scale. Sand was placed in the bottom of the filters. basins in this particular plant. Each basin is equipped One-half of the operating floor was made of glass so with perpendicular baffles at each end which extend that the central conduit, its branches, and the pipes in from ceiling to floor, and a t the incoming end there are the basement could be seen. These included pipes two sets of flocculators which aid in mixing and settling that carried the water back through the filters for of the suspended matter. There are two vertical cleaning, lines for the removal of this wash water, and baffles between the flocculatorsextending to within seven also the lines carryine the filtered water from the feet of the floor. For the model the baffles were made filters. ~hrou2houtone-ei~hthinch pipe was used The line leading to the filtered water reservoirs was of strips of balsam glued together. The flocculators
not shown, since this was under the basement floor and could not have been seen. However, this line divides so that water may enter either half of the filtered water reservoir. Just before the water enters the reservoir a water solution of chlorine is added. As previously stated, the chlorine apparatus was shown in the model. The filtered water reservoir is a basin 138 feet by 190 feet by 19 feet deep, and is divided into two equal parts. About ten inches of one end of this basin was covered with glass so that the inside could be inspected. On the inside, concrete pillars supporting the roof and a series of concrete arches supporting one wall of the iilter building were shown. For pillars three-eighths inch doweling was used, capped by a cone-shaped structure which was turned out on the lathe. The floor has an uneven structure to aid in drainage. To show this, square blocks of wood were beveled on the four sides and fastened under each pillar, after which the entire floor was covered with putty. The inside of the basin was painted gray to resemble concrete.
Water is removed from these reservoirs through two twenty-inch pipes near the bottom of each half. These connect with a thirty-six-inch line which carries the water to the high pressure pumps in the pumping station from where it is pumped to the city. Typewritten labels, pointing out important parts, giving sizes of the actual plant, and explaining what takes place a t each point were glued a t the proper places on the model. The entire structure was painted in colors, in so far as possible, to match the color scheme of the actual plant. One exception to this was in painting the pipe lines. Each was painted a different color so that an observer might more easily trace the flow of water through the plant. We are now building a similar model of the city's new sewage treatment plant, completed and placed in operation last spring. It is planned to use both of these models in the study of a unit in which the water supply and sewage treatment of a city are studied in detail.
