Pipe, PVC

A fume hood is constructed in the manner shown in figure 6. Strike drew the frame as being made of lumber but it can be made of rebar or, preferably, from PVC pipes and joints so that it can be assembled and disassembled with ease. The frame is enclosed with plastic drop cloths or any semiclear plastic sheeting. The front face of the hood is halfway covered with plastic while the bottom half is exposed to allow one to move objects in or out and to manipulate things. On top of the chamber is attached some clothes dryer duct or some such crap which is led to a leaf blower or blower motor. The exhaust from the blower is led away to the outside. 

Vinyl chloride is an industrial chemical produced in large amounts (10 ° Ib/year in the United States) and is used in the preparation of poly(vmyl chloride) Poly(vinyl chio ride) often called simply vinyl has many applications including siding for houses wall coverings and PVC piping... 

Directions are provided for preparing and using a simple coring device using PVC pipe. This experiment also details a procedure for determining the weight percent of organic material in sediments as a function of depth. 

Cost bilizers. In most cases the alkyl tin stabilizets ate particularly efficient heat stabilizers for PVC without the addition of costabilizers. Many of the traditional coadditives, such as antioxidants, epoxy compounds, and phosphites, used with the mixed metal stabilizer systems, afford only minimal benefits when used with the alkyl tin mercaptides. Mercaptans are quite effective costabilizets for some of the alkyl tin mercaptides, particularly those based on mercaptoethyl ester technology (23). Combinations of mercaptan and alkyl tin mercaptide ate currendy the most efficient stabilizers for PVC extmsion processes. The level of tin metal in the stabilizer composition can be reduced by up to 50% while maintaining equivalent performance. Figure 2 shows the two-roU mill performance of some methyl tin stabilizers in a PVC pipe formulation as a function of the tin content and the mercaptide groups at 200°C. 

PVC-chloiinated PE (>41% Cl) better impact than PVC pipe and house siding 48,331,332... 

In landfills, vinyl wastes, like all plastics, are extremely resistant to decomposition. In fact, high technology landfills are often lined with thick-gauge vinyl and use PVC pipe to handle Hquid leachate and methane gas for environmental protection. 

Vinyl chloride Power stations Chimneys Vehicle exhausts Plastic PVC pipes... 

At the Lipari Landfill site in New Jersey, the gas venting system installed in 1983 consisted of two underground 4-inch (10-cm) perforated PVC pipes and five vent risers. Two parallel PVC pipes were installed 200 feet apart prior to cap emplacement during the period of wall construction and were placed about 3 feet beneath the finished grade. The vent risers were connected to the buried manifold pipes and consisted of open pipe installed perpendicular to the underground pipes and the ground surface. Filters were not attached to the riser exit points (U.S. EPA, 1987). 

Vinyl chloride zero 0.002 Increased risk of cancer Leaching from PVC pipes discharge from plastic factories... 

Figure 2-52. Flow regime diagram for solid-water flow in 1 -in. PVC pipe. By permission, Turian, R. M. and Yuan, T. F., Fiow of Slurries in Pipelines, A.I.Ch.E. Journal, vol. 23,1977, p. 232-243.

Fig. 2-36 Stress-rupture data for rigid 2 in. diameter PVC pipe as a function of temperature.

As mentioned in Chapter 3, DI water has now replaced distilled water for most laboratory purposes. PVC pipe, which is both inexpensive and easy to install, is normally employed to carry the water to points of usage. It is very important that the lines do not have dead legs where water is allowed to stand, since this could encourage bacterial growth. In cases where sterile water is needed, special steps must be taken. The water may be boiled, which also drives out dissolved gases, or ultraviolet radiation may be employed, a common method in the cosmetics industry. Membrane filters will also effectively remove bacteria. Laboratories needing sterile water often use two bacteria removal systems of... 

Flush-mounted cup sinks are commonly used to receive small to moderate amoimts of water. These are often made of polyethylene. They can be made from 3-inch PVC pipe cemented in flush with the countertop. A reducing adapter will bring the diameter down to the standard drain pipe size. 

The engineering firm insisted on heavily plated metal valves for DI water. They had never used plastic, which the laboratory operator had successfully employed in a previous installation. Management agreed with the engineers. The water was distributed to all sinks by standard PVC pipe, which worked very well after thorough flushing. 

Polyvinylchloride (PVC) Piping, floor tile, clothing 5.6 Polystyrene (Styrofoam)Containers, heat insulators2.9 Styrene-butadiene Tires, fibers 2.0... 

Although they have an endless variety of properties, polymers can be divided into three general categories, based on their form and resistance to stretching. These are plastics, fibers, and elastomers. Plastics differ in form from fibers whereas plastics exist as blocks or sheets, fibers have been drawn into long threads. Unlike plastics or fibers, elastomers can be stretched without breaking. Polyethylene packaging films and polyvinylchloride (PVC) pipe are examples of plastics. Orion carpets are made from polymer fibers, and mbber bands are elastomers. Some polymers, such as Nylon, can be formed into both plastics and fibers. 

Heat stabilisers for PVC act by HC1 scavenging and include organotins, mixed metal salt blends, and lead compounds. The latter account for nearly 64 % of volume (in 1994), followed by barium/cadmium and organotin compounds. Cadmium-based heat stabilisers are rapidly being replaced due to environmental concerns. Barium/zinc and calcium/zinc compounds show a high growth rate. It is expected that methyltin stabilisers will soon dominate the growing PVC pipe market. 

Figure 14.1 presents the main components of a typical in situ SVE system.910 Vertical extraction wells are installed inside the contaminated zone at appropriate distances from one another. The SVE wells are typically constructed of PVC pipe, with a screened interval, which is placed within the contaminated zone. The wells are connected to blowers or vacuum pumps, which induce a continuous airflow through the pores of the unsaturated zone. The soil surface is sometimes covered with an impermeable seal, made from high density polyethylene (HDPE) or bentonite clay for example, to prevent the vertical influx of air from the surface, which might cause short-circuiting problems, and promote horizontal gas flow through the contaminated area. The airstream, which contains the contaminant vapors, passes initially through an air-water separation unit to remove the entrained moisture and is then directed to the gas treatment unit, where the contaminants are thermally destroyed or removed by adsorption. 

The original perforated collector pipes in landfills were made of concrete like those used in highway underdrain systems. As landfills became higher, the strength of such pipes became inadequate. Today, perforated PVC pipes are commonly used, as are HDPE pipes. New regulations require that all materials be tested for chemical resistance as part of the permit-approval process. 

Some builders prefer laying perforated PVC piping in the gravel before the slab is poured and connecting the perforated pipe to the exhaust pipe of the system. The use of perforated pipe may not be necessary in active systems but probably will assist a passive system. Membranes beneath the slab help us to keep a continuous radon barrier in the event of slab cracking. 

Most builders use 4 in. schedule 20 PVC pipes. Other sizes can be used but 4-in. PVC is readily available and is commonly used by builders for other purposes. Fans made for use in subslab systems are available in a variety of sizes from many vendors. The fans normally used are rated in a range of 90-150 cfm at no static pressure. Manufacturers of fans used for radon reduction are fairly quick to improve their products on advice from the people who are using their products. When the radon industry first started, many of the fans leaked at seams and joints, and required disassembly of the fan to seal those openings. Most manufacturers now supply fans that do not leak, but builders should be aware that this problem did exist and may still exist in some fans. 

It is probably beneficial to a passive system to lay a network of perforated drainage pipes in the gravel bed beneath the slab prior to the pour. The use of horizontal pipe runs and elbows in a passive system may greatly lessen the effectiveness the system and should be a voided. Some builders use a 6-in. PVC pipe in a passive system to help lessen the pressure drop. 

Contained in engine-starting fluid purchased at automotive stores. To remove liquid ether from an engine-starting aerosol can, spray the contents of the can down a 12 inch ( 30cm) length of 3/4 inch PVC pipe. The ether will condense on the sides of the pipe and fall into the jar, while the inert propellant will be released into the air. Ether is extremely volatile. Ether floats to the top of the jar. 

Figure 9. Propagating brush discharges, (a) Insulating dielectric layer of dielectric permittivity e thickness dlayer, and surface charge ey with conductive backing, (b) Example of improper use of plastic (PVC) pipe where surface charge builds up leading to risk of propagating brush discharge.

A 31.5% hydrochloric acid solution is pumped from one storage tank to another. The power input to the pump is 2 kW and is 50% efficient. The pipe is plastic PVC pipe with an internal diameter of 50 mm. At a certain time the liquid level in the first tank is 4.1 m above the pipe outlet. Because of an accident, the pipe is severed between the pump and the second tank, at a point 2.1 m below the pipe outlet of the first tank. This point is 27 m in equivalent pipe length from the first tank. Compute the flow rate (in kg/s) from the leak. The viscosity of the solution is 1.8 X 10 3 kg/m s, and the density is 1600 kg/m3. 

Monitoring wells were installed to a depth of 3-4 m into soft tailings at sites 1 and 2. The wells are constructed of 1.5 inch-OD PVC pipe with the lower 1.2 m perforated for collection of ground water. Water was sampled using a LDPE tubing- foot valve assembly. Ground water and surface waters were sampled monthly from August to November 2008. Temperature, pH, and conductivity were measured in the field and... 

Journal of Vinyl and Additive Technology 7, No.l, March 2001, p.43-50 VINYL CHLORIDE IN RURAL WATER FROM PRE-1977 APPLICATIONS OF PVC PIPE... 

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