Sink Traps

Sink traps of resistant plastic are now well accepted. They are easy to install and also easy to clean. Drains of glass pipe are sometimes seen in special installations. Some laboratories install regular thin-walled sink traps designed for kitchen use. The author s experience with them, even in the home, has been poor. 

For the three sinks, the laboratory operator suggested standard enamel sinks. The more expensive epoxy sinks, however, were chosen by the engineering firm because of their high resistance to chemicals. The fact that the city had very strict regulations with regard to discharge of chemicals did not seem to alter their recommendation. The plumbing contractor presented several types of sink traps, from which the laboratory operator picked the one he felt was most easily serviced. 

After Steam Float (Catalyst) Sink (Trap)... 

Initial Blend wt% V Initial wt. % V corrected on catalyst Float (cat.) wt% V Sink (trap) wt% V Pickup Factor % V Trap/% V Cat. 

MERCURIC BROMIDE (7789-47-1) HgBfj Noncombustible solid. Light and heat cause decomposition keep out of sunlight. Violent reaction with strong oxidizers, including chlorine trifluoride. Aqueous solution is acidic. Incompatible with acetylene, ammonia, azides (may form mercury azide, a heat- and shock-sensitive explosive), bases, caustics, amines, amides, inorganic hydroxides calcium (forms amalgam) carbide, chlorine dioxide, copper and its alloys hydrazines, indium (violent at 662°F/350°C), lithiiun, potassium, rabidium, sodium. Note Be especially careful not to allow this compound to accumulate in sink traps with many of the above incompatible... 

If you were going to construct a sink trap for the laboratory, would you use soft glass or borosilicate glass Why ... 

Pressure pellets sink when placed in water, whereas under the proper conditions, floating pellets can be produced through the extmsion process. That is accomphshed when the feed mixture contains high levels of starch that expands and traps air as the cooked pellets leave the barrel of the extmder. This gives the pellets a density of less than 1.0. Eloating pellets are desirable for species that come to the surface to feed since the aquaculturist can visually determine that the fish are actively feeding and can control daily feeding rates based on observed consumption. 

Fig. 2. Problems in wetting A, Hquids that wet the exterior before displacing gas from pores leave gas trapped in the submerged clump B, fully wetted clumps of buoyant particles do not sink C, nonwetting Hquids do not penetrate and displace gas from pores, so clump remains buoyant and caimot submerge and D, foam produced from air is drawn under the surface, sheared into small bubbles, and stabilized by the wetting agent.

Efficient models of water heaters have thicker insulation, up to three inches thick, on some of the most efficient electric water heaters. Another means to increase efficiency is installing heat traps, or anti—convection devices, on the inlet and outlet pipes. Standard heat traps consist of short pipe nipple containing a small plastic ball. On the inlet side the ball is lighter than water and floats up to seal the inlet pipe. On the outlet side the ball is heavier than water and sinks against the seal. This prevents the heated... 

Flotation process for concentrating a sulfide ora. Low-grade sulfide ores, including Cu2S, are often concentrated by flotation. The finely divided sulfide particles are trapped in soap bubbles the rocky waste sinks to the bottom and is discarded. 

Inverted-bucket steam traps contain a small bucket that becomes buoyant if steam is present and shuts off a discharge valve. The presence of condensate causes the bucket to sink and the discharge valve to open. Any entrained air is removed through a small hole in the bucket. 

Ocean prevents eutrophication. Much more water flows into the Mediterranean Sea than is required to replace evaporation from it. The excess, high salinity water exits Gibraltar below the water flowing in af fhe surface. Nufrients that enter the Mediterranean Sea from pollution sources are utilized by marine phytoplankton that sinks and exits with the outflow. Another example is that estuaries often have lower salinity or even freshwater at the surface with a denser saline layer at the bottom. An estuarine circulation occurs with nutrients being trapped in the saline bottom water. 

Manufacturers of laboratory equipment feature special sinks and drains with high chemical resistance. Sinks made from slabs of Alberene stone, which were popular for many years, often had traps made of lead. The softness of lead made the traps hard to clean out, and the job required tender loving care with a wrench of just the right size. 

Sinks supplied to clean areas should be made of stainless steel and have no overflow, and the water should be of at least potable quahty. Wherever possible, drains in clean areas should be avoided. If installed, however, they should be fitted with effective, easily cleanable traps and with air breaks to prevent backflow. Any floor channels in a clean area should be open, shallow and cleanable and should be connected to drains outside the area. They should be monitored microbiologically. Sinks and drains should be excluded from aseptic areas except where radiopharmaceutical products are being processed when sinks are a requirement. 

---