CAPTER 8. Plumbing Equipment and System 8.3 What are there equivalent between pound and grain, gallons and cubic feet, ppm and mg/L?▪ ▪ppm andmg/L 8.5 Name seven process processes used to improve the quality of water. ▪ Sedimentation, Coagulation ,Aeration ,Filtration ,Disinfection ,Fluoridation ,Softening 8.7 What mineral content is used determine the hardness in water? ▪ Carbonate orCaCO3 8.9 What is osmosis? What is reverse osmosis? ▪ OsmosisThe phenomenon of water flow through a semi-permeable membrane that blocks the transport of salts or other solutes through it. Osmosis is a fundamental effect in all biological systems. It is applied to water purification and desalination, waste material treatment, and many other chemical and biochemical laboratory and industrial processes. ▪ Reverse osmosisThe process of forcing a solvent from a region of high solute concentration through a semipermeable membrane to a region of low solute concentration by applying a pressure in excess of the osmotic pressure.
8.19 What is the function of a vacuum break? ▪ An attachment commonly placed on a bibcock valve or toilet or urinal flush valve, that prevents water from being siphoned backward into the public water system. This prevents contamination should the public water system's pressure drop. 8.21 What is the function of a shock absorber? Where should it be installed? ▪ When the flow of water in a pipe is a abruptly stopped, as by the closing of a faucet or a flushometer, the dynamic (kinetic)energy in the water must be absorbed 8.23 Why is a flushometer, rather than flush tanks, required for water closets in public facilities? ▪ A device for flushing toilets and urinals that utilizes pressure from the water supply system rather than the force of gravity to discharge water into the bowl, designed to use less water than conventional flush toilets. 8.25 What is the purpose of a drainage trap? Do water closets require traps? ▪ To prevent the backup of sewer gas
8.27 What is the difference between a waste pipe and a soil pipe? ▪ waste pipe: Pipes which convey waste water from any or all of the fixtures in a building except the water closets. ▪ soil pipe: The pipe that directs the sewage of a house to the receiving sewer, building drain or building sewer. 8.31 What is a stack? A vent? A stack vent? A vent stake? ▪ Stack: vertical portion of a SWV-piping system. ▪ vent: Pipe open to the atmosphere. ▪ vent stack: Stack that does not carry waste of any kind and that is installed primarily for providing circulation of air to and from any part of the DWV system. ▪ stack vent : Open-ended extension of a water or soil stake above the highest horizontal drain connected to the stack.
8.35 Normally, municipalities in the Unite States have separate sanitary sewer systems; however, several major cities still have combination storm and sanitary sewer systems. In such cases, can the sanitary and storm piping systems within the building be combines? ▪ The sanitary and storm water systems can be combined either inside or outside the building wall. But good engineering practice has them leave the building separately and combined outside the building wall(Facility piping systems Handbook, second edition, Michael Frankel, 2001, pp 9.45). ▪ But, in the south Korea, Separation of sanitary and storm sewer systems is decided by building law(Section 17(5) of building equipment standard). 8.39 What is the purpose of a dosing chamber in a septic tank sewage treatment systems? ▪ Component of the septic tank system that periodically discharges effluent to an approved method of disposal.
8.1.2 Processes Commonly Used to Improve Water Quality • Sedimentation : Suspended matter by precipitation Reduces the turbidity • Coagulation : Use chemicals(hydrated aluminum sulfate) Reduce turbidity and improve the color and taste of water • Aeration : Air into water to oxidize impurities to improve the color and taste • Filtration : Removes suspended material and bacteria Improve overall quality (turbidity, potability, color and taste) • Disinfection : Use chlorine gas, hypochlorite solid, ultraviolet light to disinfect bacteria • Fluoridation : Adds a fluoride chemical in water to prevent tooth decay • Softening : Replaces Ca and Ma ions with Na ions to reduce scale formation
Operating principle of a mixed-bed deionizer Principle of (a) osmosis (b) reverse osmosis • Water Purification System • A deionizing system : the tank contain a mixed bed of both cation- and anion-absorbing resins made of porous polymer minerals • A reverse osmosis(RO) , Distillation
8.2.4 Design Considerations for Water distribution Systems Vacuum breaker is installed at the branch connection to an equipment item or plumbing fixture, such as a sink, dishwasher, boiler, water closet, or urinal
8.2.4 Design Considerations for Water distribution Systems • Shock Absorption • when the flow of water in a pipe is a abruptly stopped, as by the closing of a faucet or a flushometer, the dynamic (kinetic)energy in the water must be absorbed • if it is not, the energy will be converted into a loud noise and vibration known as water hammer.