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CPVC sprinkler pipe inside a firestop mock-up. Chlorinated polyvinyl chloride (CPVC) is a thermoplastic produced by chlorination of polyvinyl chloride (PVC) resin. CPVC is significantly more flexible than PVC, and can also withstand higher temperatures. Uses include hot and cold water delivery pipes and industrial liquid handling.
Facultative lagoon (polishing pond) providing tertiary treatment after a constructed wetland in Hamburg-Allermöhe, Germany. Overflow from the facultative lagoon may be routed through one or more polishing ponds supporting lower populations of anaerobic micro-organisms and a higher proportion of aerobic organisms adapted to survival in lower concentrations of organic material.
In vacuum applications, a cold trap is a device that condenses all vapors except the permanent gases (hydrogen, oxygen, and nitrogen) into a liquid or solid. [ 2 ] [ needs update ] The most common objective is to prevent vapors being evacuated from an experiment from entering a vacuum pump where they would condense and contaminate it.
PVC stands for polyvinyl chloride, and it has become a common replacement for metal piping. PVC should be used only for cold water, or for venting. CPVC can be used for hot and cold potable water supply. Connections are made with primers and solvent cements as required by code. [31]
The system may consist of a single pond or several ponds in a series, each pond playing a different role in the removal of pollutants. After treatment, the effluent may be returned to surface water or reused as irrigation water (or reclaimed water) if the effluent meets the required effluent standards (e.g. sufficiently low levels of pathogens).
Traps at different levels in the marsh came into operation as the water level rose and fell. The traps at Budj Bim are seen as a form of Indigenous aquaculture dating back at least 6,600 years (older than the Pyramids of Giza [9]), with the Muldoon traps system seen as the world's oldest stone walled fish trap, and longest used fish trap in the ...
Reoxygenating the system water is a crucial part to obtaining high production densities. Fish require oxygen to metabolize food and grow, as do bacteria communities in the biofilter. Dissolved oxygen levels can be increased through two methods, aeration and oxygenation. In aeration air is pumped through an air stone or similar device that ...
Trout do best in spring water because it keeps a constant temperature, while catfish need a strong flow, about 80 litres per second for every 0.4 hectares of raceway. A backup water supply should be positioned so, if the water supply or pump fails, it can flow by gravity into the start of the raceway. [16]