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27-421: The entire region of Jajce is rich in natural heritage that cannot be viewed in isolation from the built heritage. In Jajce, these two components are closely intermingled. The Pliva valley is located in the northern part of central Bosnia and Herzegovina and known for its tranquil mountains rich in forests and abundance of nature, wildlife and especially bodies of water. The valley is dominated by two unique rivers,

54-788: A national monument of Bosnia and Herzegovina . Local farmers used the mills to grind wheat into flour until the Second World War and some afterward, with a heyday of production being during the days of the Austro-Hungarian Empire. At the confluence with the Vrbas , the Pliva forms the magnificent 22 meters high Pliva Waterfall for which the town of Jajce is famous and along with numerous historic, cultural, architectural and natural monuments represent towns robust and valuable heritage and tourist attraction. The Pliva river

81-553: A raw material for the chemical industry , in particular for the production of polyvinyl chloride . Locally produced acetylene is more economical than using imported oil. Production of calcium carbide in China has been increasing. In 2005 output was 8.94 million tons, with the capacity to produce 17 million tons. In the United States, Europe, and Japan, consumption of calcium carbide is generally declining. Production levels in

108-497: A serious hazard. The presence of flammable gases in coal mines led to miner safety lamps such as the Davy lamp , in which a wire gauze reduces the risk of methane ignition. Carbide lamps were still used extensively in slate , copper , and tin mines where methane is not a serious hazard. Most miners' lamps have now been replaced by electric lamps . Carbide lamps are still used for mining in some less wealthy countries, for example in

135-481: Is a chemical compound with the chemical formula of Ca C 2 . Its main use industrially is in the production of acetylene and calcium cyanamide . The pure material is colorless, while pieces of technical-grade calcium carbide are grey or brown and consist of about 80–85% of CaC 2 (the rest is CaO ( calcium oxide ), Ca 3 P 2 ( calcium phosphide ), CaS ( calcium sulfide ), Ca 3 N 2 ( calcium nitride ), SiC ( silicon carbide ), C ( carbon ), etc.). In

162-421: Is a ripening agent . However, this is illegal in some countries as, in the production of acetylene from calcium carbide, contamination often leads to trace production of phosphine and arsine . These impurities can be removed by passing the acetylene gas through acidified copper sulfate solution, but, in developing countries, this precaution is often neglected. Calcium carbide is used in toy cannons such as

189-481: Is an endothermic reaction requiring 110 kilocalories (460 kJ) per mole and high temperatures to drive off the carbon monoxide. This method has not changed since its invention in 1892: The high temperature required for this reaction is not practically achievable by traditional combustion, so the reaction is performed in an electric arc furnace with graphite electrodes. The carbide product produced generally contains around 80% calcium carbide by weight. The carbide

216-514: Is crushed to produce small lumps that can range from a few mm up to 50 mm. The impurities are concentrated in the finer fractions. The CaC 2 content of the product is assayed by measuring the amount of acetylene produced on hydrolysis . As an example, the British and German standards for the content of the coarser fractions are 295 L/kg and 300 L/kg respectively (at 101 kPa pressure and 20 °C (68 °F) temperature). Impurities present in

243-460: Is famous for its clean water, particularly near the source in the mountains and its richness in fish which makes the river so attractive for flyfishing , not just in Bosnia and Herzegovina but also in the region. A part of the 16th FIPS-Mouche European Fly Fishing Championship was held on the lake. The fishing societies Zlatovčica from Jajce and Jezero are managing the fishing from the lake to

270-617: The Big-Bang Cannon , as well as in bamboo cannons . In the Netherlands calcium carbide is used around new-year to shoot with milk churns. Calcium carbide, together with calcium phosphide , is used in floating, self-igniting naval signal flares , such as those produced by the Holmes' Marine Life Protection Association . Calcium carbide is used to determine the moisture content of soil. When soil and calcium carbide are mixed in

297-543: The Sava river, therefore the Pliva is part of the Sava river basin. The river Pliva is characterized by the specific geological nature of the terrain and distinctive morphological and hydrological features, very similar as nearby Una River . The river bed of the Pliva, from the village of Jezero to its confluence with the Vrbas , consists of tufa also known as travertine which forms travertine barriers. In this area

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324-461: The silver mines near Potosí , Bolivia . Carbide lamps are also still used by some cavers exploring caves and other underground areas, although they are increasingly being replaced in this use by LED lights. Carbide lamps were also used extensively as headlamps in early automobiles, motorcycles and bicycles, but have been replaced entirely by electric lamps. Calcium carbide is sometimes used as source of acetylene, which like ethylene gas,

351-458: The Pliva and the Janj and two natural lakes on the Pliva river. The Pliva river flows from West to East, is 26.8 kilometers long, and has an average discharge artificially set for a biological minimum of 3.0 m near town of Jajce at the waterfall site. Total watershed area of the Pliva is 1,326 km. Its source is some 8 kilometers upstream of the town of Šipovo near Pljeva at the foot of

378-561: The Pliva lakes lie in a basin of karstic rock, mainly dolomite and limestone , which has given rise to their most distinctive feature, same as nearby Una River in Bosnia and Herzegovina and Plitvice Lakes in Croatia . The lakes are separated by natural dams of travertine, which is deposited by the action of moss, algae and bacteria. The encrusted plants and bacteria accumulate on top of each other, forming travertine barriers which grow at

405-495: The Pliva river has created three natural lakes, Veliko Plivsko Lake , Malo Plivsko Lake and Okruglo Lake , with countless low cascades and travertine barriers ( tufa barriers), which causing these lakes to form, slowing the river and deepening it. At the village of Jezero the Pliva flows into the larger of two lakes, Veliko Plivsko Lake ( veliko meaning large), then into two smaller Malo Plivsko Lake ( malo meaning small) and Okruglo Lake ( okruglo meaning round). Both of

432-605: The US during the 1990s were 236,000 tons per year. Calcium carbide reacts with nitrogen at high temperature to form calcium cyanamide : Commonly known as nitrolime , calcium cyanamide is used as fertilizer. It is hydrolysed to cyanamide , H 2 NCN. Calcium carbide is used: Calcium carbide is used in carbide lamps . Water dripping on carbide produces acetylene gas, which burns and produces light. While these lamps gave steadier and brighter light than candles, they were dangerous in coal mines, where flammable methane gas made them

459-513: The carbide include calcium phosphide , which produces phosphine when hydrolysed. This reaction was an important part of the Industrial Revolution in chemistry, and was made possible in the United States as a result of massive amounts of inexpensive hydroelectric power produced at Niagara Falls before the turn of the 20th century. The electric arc furnace method was discovered in 1892 by T. L. Willson , and independently in

486-501: The confluence with Vrbas . Jajce Too Many Requests If you report this error to the Wikimedia System Administrators, please include the details below. Request from 172.68.168.133 via cp1102 cp1102, Varnish XID 552246634 Upstream caches: cp1102 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 05:48:25 GMT Calcium carbide Calcium carbide , also known as calcium acetylide ,

513-575: The largest chemical factory for production of calcium carbide in Europe at the time. The first hydroelectrical power station in Southeast Europe became operational on 24 March 1899. Today plans of construction of numerous small hydro power stations on the rivers Pliva and Janj are already undergo, although local population started expressing deep resentment and disapproval, and in some cases organized protests stopping ongoing works, at least for

540-486: The mountain of Smiljevac - Jastrebnjak , where the Pliva springs out from two very strong karstic springwells at 483 meters above sea level. The main tributary of the Pliva is the Janj , that flows into the Pliva from the right, in the center of the town of Šipovo . At the confluence, both the Janj and the Pliva are approximately the same size, and both rivers have the same amount of water. Some 12 kilometers downstream, at

567-450: The presence of trace moisture, technical-grade calcium carbide emits an unpleasant odor reminiscent of garlic. Applications of calcium carbide include manufacture of acetylene gas, generation of acetylene in carbide lamps , manufacture of chemicals for fertilizer, and steelmaking. Calcium carbide is produced industrially in an electric arc furnace from a mixture of lime and coke at approximately 2,200 °C (3,990 °F). This

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594-610: The rate of about 1 cm per year. The very first hydroelectric power station in Bosnia and Herzegovina was built on the Pliva river in 1899. It was also the very first of its kind in the Balkans. This facility was constructed and exploited by Austrian industrialist Dr. Josef Kranz and his "Bosnische-Elektrizitäts AG" company, whose successor later became " Elektro-Bosna ". The power station had an installed capacity of 8 MW, and supplied electricity for "Elektro-Bosna" situated in Jajce,

621-506: The same year by H. Moissan . In Jajce , Bosnia and Herzegovina , the Austrian industrialist Josef Kranz and his "Bosnische-Elektrizitäts AG" company, whose successor later became "Elektro-Bosna" , opened the largest chemical factory for the production of calcium carbide at the time in Europe in 1899. A hydroelectric power station on the Pliva river with an installed capacity of 8 MW

648-448: The time being. The Janj is also considered for construction of several small hydro, but location is highly controversial as a place of great natural and environmental value. There is a cluster of small wooden hut-like watermills on the Pliva, on steep ford where the water spills between two lakes, from upper Veliko Plivsko into lower Malo Plivsko lake. These mills are out of their primary function today, but are preserved and maintained as

675-477: The village of Jezero , the Pliva flows into the largest of three lakes, Veliko Plivsko Lake , then into two smaller lakes: Malo Plivsko Lake and Okruglo Lake . After the Pliva river passed through the towns of Šipovo and Jezero , and through both Plivska lakes, it reaches the town of Jajce where it meets with the Vrbas river . The Pliva river is a left tributary of the Vrbas that, on its way north, flows into

702-555: Was constructed to supply electricity for the factory, the first power station of its kind in Southeast Europe, and became operational on 24 March 1899. Pure calcium carbide is a colourless solid. The common crystalline form at room temperature is a distorted rock-salt structure with the C 2 units lying parallel. There are three different polymorphs which appear at room temperature: the tetragonal structure and two different monoclinic structures. The reaction of calcium carbide with water, producing acetylene and calcium hydroxide ,

729-484: Was discovered by Friedrich Wöhler in 1862. This reaction was the basis of the industrial manufacture of acetylene , and is the major industrial use of calcium carbide. Today acetylene is mainly manufactured by the partial combustion of methane or appears as a side product in the ethylene stream from cracking of hydrocarbons. Approximately 400,000 tonnes are produced this way annually (see acetylene preparation ). In China, acetylene derived from calcium carbide remains

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