Barite, production

Production and Consumption. About 80% of the world s barite production is used as a weighting agent for the muds ckculated in rotary drilling of oil and gas wells (see PETROLEUM, DRILLING FLUIDS AND OTHER OIL RECOVERY CHEMICALS). Table 2 shows the U.S. production—consumption balance. The 1988 demand for barite increased nearly 40% over that recorded in 1987. However, by the end of 1988, oil prices had declined and renewed economic uncertainties depressed exploration and development activity. Barite demand fell accordingly and imports of lower cost foreign product exceeded domestic production. 

Table 3. World Barite Production, Reserves, and Reserve Base, 10 t ...

In 1977, some 44% of worldwide barite production (5.35x10 tons) was from the USA (Greenwood and Earnshaw 1988), though barite production by China is becoming increasingly important (Griffiths... 

The fused product contains about 60—85% barium sulfide, unreacted barium sulfate, and impurities present in barite and ash. The soluble barium sulfide is extracted from the mixture with water and separated from the insoluble impurities by filtration. 

One commercial process for producing sodium sulfide is as a by-product of barium carbonate production (see Barium compounds). Barite ore, BaSO, is reduced with carbon at 800°C to produce cmde barium sulfide (black ash), which is then leached to dissolve the barium sulfide in solution. The solution is then reduced using sodium carbonate to produce barium carbonate, leaving a weak sodium sulfide solution as the by-product. The sodium sulfide solution may then be concentrated and flaked or crystallized. 

In the glass (qv) and ceramic industry (see Ceramics), barite can be used both as a flux, to promote melting at a lower temperature or to increase the production rate, and as an additive to increase the refractive index of glass. The viscosity of barite-containing glass often needs to be raised. Alumina in the form of feldspar is sometimes used. To offset any color produced by iron from the barite addition, more decolorizer may be needed. When properly used, barytes help reduce seed, increase toughness and brilliancy, and reduce annealing time. Barite is also a raw material for the manufacture of other barium chemicals. 

Most barium compounds are prepared from reactions of barium carbonate [513-77-9] BaCO, which is commercially manufactured by the "black ash" process from barite and coke ki a process identical to that for strontium carbonate production. Depending on the co-product, soda ash and/or carbon dioxide are also consumed. 

Because of its extreme insolubiUty, barium sulfate is not toxic the usual antidote for poisonous barium compounds is to convert them to barium sulfate by administering sodium or magnesium sulfate. In medicine, barium sulfate is widely used as an x-ray contrast medium (see Imaging TECHNOLOGY X-RAY technology). It is also used in photographic papers, filler for plastics, and in concrete as a radiation shield. Commercially, barium sulfate is sold both as natural barite ore and as a precipitated product. Blanc fixe is also used in making white sidewall mbber tires or in other mbber appHcations. 

A U.S. Bureau of Mines survey covering 202 froth flotation plants in the United States showed that 198 million tons of material were treated by flotation in 1960 to recover 20 million tons of concentrates which contained approximately 1 billion in recoverable products. Most of the worlds copper, lead, zinc, molybdenum, and nickel are produced from ores that are concentrated first by flotation. In addition, flotation is commonly used for the recoveiy of fine coal and for the concentration of a wide range of mineral commodities including fluorspar, barite, glass sand, iron oxide, pyrite, manganese ore, clay, feldspar, mica, sponumene, bastnaesite, calcite, garnet, kyanite, and talc. 

The log(wBj,2+)i(WgQ2-)i values for the solutions of the previous investigators T = 25-100°C) and ob.serve d morphologies of barite in their experiments) are compared as. shown in Fig. 1.55. It shows that the morphology of barite crystals changes with an increase in the concentration product, from well-formed (rectangular,... 

The concentration products obtained in the experiment by Shikazono (1994) can be compared with the solubility product for large well-formed polyhedral barite crystals... 

Figure 1.55. The relationships between the concentration product, (Ba " )i(S04 )i, at the initiation of barite precipitation, and morphologies of barite crystals (Shikazono, 1994). The dashed line represents the boundary between dendritic barite crystals and well-formed rhombohedral, rectangular, and polyhedral barite crystals. The 150°C data are from Shikazono (1994) the others from other investigations. D dendritic (spindle-like, rodlike, star-like, cross-like) barite Dp feather-like dendritic barite W well-formed rectangular, rhombohedral, and polyhedral barite. The boundary between the diffusion-controlled mechanism (Di) and the surface reaction mechanism (S) for barite precipitation at 25°C estimated by Nielsen (1958) The solubility product for barite in 1 molal NaCl solution at 150°C based on data by Helgeson (1969) and Blount (1977). A-B The solubility product for barite in 1 molal NaCl solution from 25 to 150°C based on data by Helgeson (1969).

The various morphological features of barites from the Kuroko and Mariana deposits, when combined with the experimental studies on barite precipitation, suggest that the surface reaction mechanism was dominant for the formation of these barites. This implies that the concentration product, m 2+) msol-), at the initiation of barite precipitation was probably less than ca. 100 times that for equilibrium. 

A common problem in offshore petroleum production is that sulfate scale may form when seawater is injected into the formation during waterflooding operations. The scale forms when seawater, which is rich in sulfate but relatively poor in Ca++ and nearly depleted in Sr++ and Ba++, mixes with formation fluids, many of which contain bivalent cations in relative abundance but little sulfate. The mixing causes minerals such as gypsum (CaSC>4 2H2O), anhydrite (CaSC>4), celestite (SrSOzO, and barite (BaS04, an almost insoluble salt) to become saturated and precipitate as scale. 

Barite A mineral form of barium sulfate that is most common beneath surface waters of high productivity. The barium is primarily biogenic in origin. 

The Mn-subunit exposed in the Arnold pit contains up to 13% Mn and 13700 ppm Ba with associated elements consistent with distal hydrothermal products. Microprobe analysis determined barite to be present as inclusions within and on the margins of pyrolusite, demostrating Mn and Ba deposition from the same fluid. Such anomalous enrichments are atypical of basinal settings other than those receiving input from hydrothermal discharge. 

Barium sulfide occurs in the form of hlack ash, which is a gray to hlack impure product obtained from high temperature carbonaceous reduction of barite. It is the starting material in the manufacture of most barium compounds including barium chloride and barium carbonate. It is used in luminous paints for dehairing hides as a flame retardant and for generating H2S. 

The product, black ash, is a gray or black powder containing carbonaceous impurities and unreacted barite. Barium sulfide is separated from impurities by extraction with hot water and filtration. It is obtained as an aqueous solution of 15 to 30% strength. The commercial product is 80% to 90% BaS. 

Environmental Protection. During the reduction of barite and the calcination of Sachtolith and lithopone, sulfur dioxide is liberated. This is removed from the waste gas in a purification stage which is based on the reversible, temperature-dependent solubility of sulfur dioxide in poly glycol. The absorbed sulfur dioxide can be recovered as a liquid product or as a raw material for sulfuric acid. Any soluble barium in the residue from the dissolution of the fused BaS is removed by treatment with... 

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