Lead pipes

The reaction is carried out in a lead retort one suitable for the laboratory can be made from a piece of lead piping, bent like a retort and closed at the shorter end. This is charged with fluorspar and the acid and heated, and the hydrogen fluoride is distilled into a polythene vessel. 

Lead is a bluish-white metal of bright luster, is very soft, highly malleable, ductile, and a poor conductor of electricity. It is very resistant to corrosion lead pipes bearing the insignia of Roman emperors, used as drains from the baths, are still in service. It is used in containers for corrosive liquids (such as sulfuric acid) and may be toughened by the addition of a small percentage of antimony or other metals. 

Lead is easily cast and formed. It is one of the oldest known metals, used before 3000 BC. Early civilizations used lead extensively for ornamental and stmctural uses, and lead pipes used for the transportation of water by the Romans have endured. 

Fig. 4.2. When we heat plumbers solder to about 210°C, and make it "pasty", we con "wipe" it into elegantly curved shapes. Lead pipes hove been joined in this way for centuries.

The Phoenicians were building water ducts and pipelines of clay, stone, or bronze about 1000 B.c. and the construction of long-distance water pipelines flourished in imperial Roman times. The water supply lines of Rome had a total length of about 450 km, and consisted mainly of open or covered water ducts. The Roman writer Vitruvius gives a fairly accurate description of the manufacture of lead pipes [8]. The pipes were above ground and were often laid beside the roadway or in ducts inside houses [9]. 

Form-sand, m. molding sand, -schwindung, /. shrinking, shrinkage, -stahl, m. structural steel profile steel, -stein, m. shaped brick (Lead) pipe stone, -stiiek, n. shaped part, -ton, m. molding clay. 

Transportation of natural gas through pipelines began in the United States in the early part of the nineteenth century. One of the first known uses occurred in 1821 with the building of a system of metallic lead pipes to transport natural gas from a nearby shallow well to commercial establishments in Fredonia, New York, Gas lights—burning gas made from coal—illuminated the streets of Baltimore beginning in 1816. 

Failure of the metal can be the most important effect of a corrosive water, but other eff ts may arise from small concentrations of metallic ion produced by corrosion. A natural water passed through a lead pipe may contain a toxic concentration of that metal with copper there is a greater tolerance from the toxicity point of view but staining of fabrics and sanitary fittings may be objectionable. With iron, similarly, discoloration of the water may be unpleasant and may cause damage to materials being processed. 

Lead pipes The corrosion resistance of lead is generally excellent, but it is attacked by certain waters. This is usually of little significance so far as deterioration of the pipe is concerned, but is important because of danger to health, since lead is a cumulative poison even very small doses taken over long periods can produce lead poisoning. It is for this reason that its use for carrying potable water has been discontinued. 

Lead levels ranging between 10 and 30 pg/L can be found in drinking water from households, schools, and office buildings as a result of plumbing corrosion and subsequent leaching of lead. The combination of corrosive water and lead pipes or lead-soldered joints in either the distribution system or individual houses can create localized zones of high lead concentrations that exceed 500 pg/L (EPA 1989f). 

According to EPA s National Compliance Report for calendar year 1996 (EPA 1998g), the vast majority of people in the nation received water from systems that had no reported violations of the maximum contaminant level and treatment technique requirements or significant monitoring and reporting requirements. Lead has a maximum permissible level of 15 pg/L delivered to any user of a public water system. Lead and copper are regulated in a treatment technique that requires systems to take tap water samples at sites with lead pipes or copper pipes that have lead solder and/or are served by lead service lines. The water system is required to take treatment steps if the action level (15 pg/L for lead) is exceeded in more than 10% of tap water samples. For calendar year 1996, nearly 6 million people in the United States were served by community water systems that reported maximum contaminant level and treatment technique violations of the Lead and Copper Rule (EPA 1998g). 

Prohibition on use of lead pipes, solder, and flux Yes 40 CFR 141.43 EPA 1987c... 

ORIGIN OF NAME The name "lead" is the old Anglo-Saxon word for this well-known element, and the symbol for lead (Pb) is derived from the Latin word plumbum, which is also the root word for "plumber," related to the use of lead pipes in ancient Roman plumbing systems. Some of these lead pipes can still be seen in parts of modern-day Rome. 

At one time canned foods were a significant source of lead because of poor-quality solder joints in the cans. High-acid goods, such as tomatoes, would leach lead from the cans. Finally, contamination of drinking water with lead occurs primarily from lead solder joints or old fixtures and occasionally lead pipe was used to bring water to a home. As with many metals, lead was used in a number of remedies, some of which are still available and used by some ethnic groups. 

When detn of yield is required, use a, large sample of glycerol (about lOOg) and Method No 1, which is conducted in an open lead casserole of about 1 liter capacity using for an agitator a thermometer inserted in a lead pipe with a slot for reading... 

Severe muscle rigidity, typically lead pipe or plastic ... 

Health authorities have warned against the use of copper or stainless steel fittings in contact with the lead piping that is still found in domestic plumbing in some older houses in Britain. 

Support an hemispherical iron dish of 10 cm. diameter (or an iron crucible) on a ring stand and place in it about 75 g. of sodium nitrate. Heat the nitrate until it melts and just begins to evolve bubbles of oxygen. While maintaining a steady temperature, drop in pieces of granulated lead or chopped-up lead pipe, stirring well with an iron rod (old round file) after each addition. A little more than the equivalent of lead should be added, since some of it will be oxidized by the air. For this reason, a flat iron sand-bath dish is not suitable for the experiment. The reduction of the nitrate is rapid, and if much lead is added at a time, the mass may become incandescent. 

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