Water-supply systems pipe materials

Testing the potential of pipe materials to promote biofilm growth is needed because it may affect the taste, odor or turbidity of drinking water and may cause non compliance with microbiological water quality parameters and a risk to consumers health. Because EU Drinking Water Directive (98/83/EC) controls the water quality at the consumers tap instead of the point of supply, it is important to be assessed if the pipe material in drinking water supply systems release substances that may enhance or inhibit attached microbial growth. 

Biofilm study was carried out in the drinking water supply system DWSS"Yovkovtsy , that supply with water the region of Veliko Tamovo, and in the laboratory model of water distribution system. Some experiments were performed 1) to determine microbiological composition of biofilm samples scraped from mild steel or reinforced concrete s main pipe line and concrete tank of DWSS Yovkovtsy 2) to study biofilm formation process on test pipe from PVC, PE, stainless steel and carbon steel in a laboratory model of drinking water distribution system under flow velocity 0,006 cm/s. 3) to study dynamics of biofilm formation process on polypropylene, the pipe material used during the last years in Bulgaria, in a model water distribution system under flow velocities 0.3 m/s, 0.5 m/s, 0.7 m/s and 1 m/s. 

Suppose that we are going to build an oil refinery, a city water supply system, or an aircraft carrier. We will have to deal with a very large number of fluid flows. We could calculate the friction effect for each from Fig. 6.10. However, in any of these projects, we would probably use U.S. standard pipe sizes for practically all the flows From App. A.3 we see that they constitute a fairly small number of sizes. For pipes of any size and of the same material, the... 

Use of lead materials—The use of solder or flux containing more than 0.2% lead or pipes and pipe fittings containing more than 8% lead is prohibited in public water supply systems. Public notification is required where lead is used in construction materials of the public water supply system, or where water is sufficiently corrosive to cause leaching of lead from the distribution system or lines. 

ISO 2898-1 1996 Plastics - Plasticized poly(vinyl chloride) (PVC-P) moulding and extrusion materials - Part 1 Designation system and basis for specifications ISO 2898-2 1997 Plastics - Plasticized poly(vinyl chloride) (PVC-P) moulding and extrusion materials - Part 2 Preparation of test specimens and determination of properties ISO 3114 1977 Unplasticized polyvinyl chloride (PVC) pipes for potable water supply -Extractability of lead and tin - Test method... 

When considering the application of foam to hazardous material spills, key requirements include an adequate water supply, the foam concentrate, appropriate proportioning equipment, piping, foam makers, and discharge devices and protective equipment for the personnel involved. Activation may be automatic, but in most cases it is manual. There are four types of application systems. They include fixed, semifixed, mobile, and portable (NFPA 11, 1988). 

Wei Mon Industry Co. was established in 1987 to manufacturing concrete piping materials as well as contracting major civil infrastructure projects such as water supply pipelines, sewerage systems, and land developments. Since 1996, Wei Mon started to research and develop natural and environmentally-friendly products, including Biodegradable Plastic Products. 

Each SCB incorporates a water washdown system to periodically clean inner SCB surfaces that become contaminated. This is accomplished to maintain the working environment as clean as possible to maintain product purity. The system consists of a supply manifold located in Room 114, water supply piping inside of the Zone 2A canyon, nozzles on the top of each SCB, and a drain system that will allow injected water to drain out of the SCB into a collection tank. The system is not permanently connected to a water supply and would only be activated when ail process materials, including radioactive targets, have been removed from the SCB which is to be cleaned. To effect cleaning of the SCB, a pressurized water filled container is connected to the system each time a cleaning operation is desired. The supply of water to a specific SCB is controlled by valves in the supply header. 

A failure in a pressurized water system will not have nearly the same results as piping systems for flammable or toxic materials. Storm and sanitary systems depend on gravity to move the contents. Leaks may contaminate underground water sources and leaking material may leach to the surface or into water supplies and create health hazards. 

The sizing of piping is based upon a hydraulic analysis for the water distribution network for the WCCE. The main delivery pipe should be sized to provide 150% of the design flow rate. A residual pressure and flow requirement at the most remote hydrocarbon process or storage location from the supply source dictates the sizing for the remaining system. Normal reliability requirements usually suggest that minimum of two sources of supply be available that are in themselves remote from each other. Therefore two remote flow calculations must be performed to determine the minimum pipe distribution size. NFPA 24 requires that the minimum residual pressure available in a fire main not be less than 6.9 bars (100 psi.). Velocity calculations should be performed which verify flows are not more than the limits of the material that is employed. 

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