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  LIME—199845.1 L IME By M. Michael Miller  Domestic survey data and tables were prepared by Rosanna Kim, statistical assistant, and the world production table wasprepared by Ronald L. Hatch, international data coordinator. Lime is an important chemical with numerous chemical,industrial, and environmental uses in the United States. Someevidence of its use as a lime mortar has been found at a site inwhat is now eastern Turkey that dates from 7,000 to 14,000years ago. More definite evidence of its use in mortars in the Near East and in the former Yugoslavia dates from 8,000 yearsago. In Tibet, it was used to stabilize clays in the constructionof the pyramids of Shersi, which were built 5,000 years ago. The ancient Egyptians used lime as an ingredient in mortar and plaster. The Chinese, Greek, Roman, and other ancientcivilizations used lime for construction, agriculture, bleaching,and tanning (Oates, 1998a, p. 3-4). Its uses began expandingwith the advent of the industrial revolution, but it remained primarily a construction commodity until the rapid growth of the chemical process industries at the beginning of the 20thcentury. At the turn of the 20th century, more than 80% of thelime consumed in the United States went for construction uses, but currently more than 90% is being consumed for chemicaland industrial uses.The term “lime” as used throughout this chapter refers primarily to six chemicals produced by the calcination of high- purity calcitic or dolomitic limestone followed by hydrationwhere necessary. They are (1) quicklime, calcium oxide (CaO);(2) hydrated lime, calcium hydroxide [Ca(OH) 2 ]; (3) dolomiticquicklime (CaO . MgO); two types of dolomitic hydrate, (4) type N [Ca(OH) 2. MgO] and (5) type S [Ca(OH) 2. Mg(OH) 2 ]; and (6)dead-burned dolomite. Nondolomitic quicklime and hydratedlime are also called high-calcium lime. Lime also can be produced from a variety of calcareous materials, such asaragonite, chalk, coral, marble, and shell. Lime is alsoregenerated; that is, produced as a byproduct, by paper mills,carbide plants, and water-treatment plants. Regenerated lime,however, is beyond the scope of this report. Production Lime is a basic chemical that was produced as quicklime in32 States and Puerto Rico (table 2). Hydrated lime was produced in four additional States in which hydrating plantsused quicklime shipped in from out of State. Principal producing States were, in descending order of production,Missouri, Kentucky, Alabama, Ohio, Texas, and Pennsylvania.Domestic production data for lime are derived by the U.S.Geological Survey (USGS) from two separate, voluntarysurveys of U.S. operations. The survey used to prepare thisreport is the annual “Lime” survey. Quantity data are collectedfor 28 specific and general end uses, and value data arecollected by type of lime, such as high calcium or dolomitic. Because value data are not collected by end use, value datashown in table 4 are determined by calculating the averagevalue per metric ton of quicklime sold or used for eachrespondent and then multiplying it by the quantity of quicklimethe respondent reported sold or used for each end use. Thesame calculation is performed for hydrated lime sold or used.Table 4 displays the total quantity sold or used for an end useand the total value of the quicklime and hydrate sold or used for that end use calculated as described above.The USGS maintains a list of operations classified as producing or idle; in 1998, there were 115 operations listed.Four of these operations are not surveyed at the producers’request, and estimates are made by using reported prior-year  production figures or other industry data. Three of theseoperations were idle in 1998. Of the 108 operations to whichthe 1998 annual survey request was sent, 103 responded,representing 94% of the total sold or used by producers.Production for five nonrespondents was estimated by usingreported prior-year production figures.Total lime sold or used by domestic producers in 1998increased by about 454,000 metric tons (500,000 short tons) to20.1 million tons (22.2 million short tons) compared with thatof 1997 (table 1). Production included the commercial sale or captive consumption of quicklime, hydrated lime, and dead- burned refractory dolomite. These products were valued at$1.22 billion. Commercial sales increased by 556,000 tons(613,000 short tons) to a record high of 17.8 million tons(nearly 19.6 million short tons), and captive consumptiondecreased by 102,000 tons (112,000 short tons) from therevised 1997 figures to about 2.29 million tons (2.53 millionshort tons). Data in table 1 now include production fromPuerto Rico, as do the revised figures for 1996 and 1997. Thisfacilitates comparison of data in the various tables.The lime industry went through some major changes incompany ownership in 1998. Carmeuse Lime, Inc., which hadacquired Marblehead Lime Co. in 1994 and the Pennsylvanialime operations of Tarmac America, Inc. (formerly WimpeyMinerals PA, Inc.) in 1996, acquired Pittsburgh-based DravoCorp. (Dravo Corp., 1998). Dravo was the second largest lime producer in the United States with lime plants in Alabama andKentucky and a hydrating plant in Louisiana. Carmeuse alsoannounced a planned joint-venture merger of its NorthAmerican lime operations with those of Lafarge S.A. Lafargeowned lime plants in Ohio, Texas, and Canada that wereacquired as part of Lafarge’s takeover of Redland PLC. The joint-venture company will be owned 60% by Carmeuse and40% by Lafarge (Industrial Minerals, 1998). Carmeuse andLafarge finalized their agreements effective February 18, 1999  LIME—199845.2 (Carmeuse North America, 1999). Refractories producer A.P.Green Industries, Inc. (parent of APG Lime Corp.), wasacquired by Global Industrial Technologies, Inc. Global’s purpose in making the acquisition was to merge the refractoriesoperations of A.P. Green with those of its subsidiary Harbison-Walker Refractories Co. (Global Industrial Technologies, Inc.,1998). In a deal finalized on May 22, Oglebay Norton Co.acquired U.S. and Canadian lime and limestone producer Global Stone Corp. (Oglebay Norton Co., 1998). On June 9,1998, Graymont Ltd. announced that it had acquired 100% of GenLime LP of Genoa, OH, and Bellefonte Lime Co. of Bellefonte, PA. These operations will become part of Graymont’s East Division Operations, which includes GraybecCalc, Inc., and Graystone Materials, Inc. Graymont (parent of Continental Lime, Inc., and Continental Lime Ltd.) nowoperates 14 lime plants in Canada and the United States(National Lime Association, 1998). The small Lee Lime Corp.operation in Lee, MA, which became part of Medusa MineralsCo. in 1997, became part of Southdown, Inc., with the merger of cement producers Southdown and Medusa Corp. in 1998(Drake, 1998).With all the acquisition and merger activities, 1998 was arelatively quiet year for plant construction. Carmeuse Limecontinued renovation and construction work on its dolomiticlime plant at Maple Grove, OH. The project involves therefurbishment of two straight rotary kilns with a combinedcapacity of 1,090 tons per day (1,200 short tons per day). Themodernization project was expected to be completed inSeptember 1999. Under a long-term contract with DowChemical Co., Carmeuse is committed to supply more than181,000 tons per year (200,000 short tons per year) to Dow’sLudington, MI, magnesium hydroxide plant (National LimeAssociation, 1999). Mississippi Lime Co. started up its new120,000-ton-per-year (132,000-short-ton-per-year) Maerz twinvertical shaft parallel flow regenerative kiln (Don Muller,Mississippi Lime Co., oral commun., 1999). Much of theconstruction work on the new Palmetto Lime LLC plant inCharleston, SC, was completed in 1998, and the plant took itsfirst delivery of limestone in December, but startup of the plantwas not expected until summer 1999 (Rick Werner, PalmettoLime LLC, oral commun., 1999).Of the 49 companies manufacturing lime at the end of 1998,31 were primarily commercial producers, and 18 were predominantly captive producers. The 31 commercial producers operated 62 lime plants producing quicklime and 8separate hydrating plants (including 1 lime plant that was idle but operated its hydrator). The 18 captive producers operated42 plants producing quicklime primarily for internal companyuse. At year’s end, the top 10 companies were, in descendingorder of production, (1) Carmeuse Lime, which consisted of Carmeuse Pennsylvania, Inc., Dravo Lime Co., andMarblehead Lime; (2) Chemical Lime Co.; (3) MississippiLime; (4) Continental Lime; (5) Global Stone; (6) APG Lime;(7) Martin Marietta Magnesia Specialties, Inc.; (8) BellefonteLime; (9) Lafarge Lime, Inc.; and (10) U.S. Lime andMinerals, Inc. These companies operated 40 lime plants and 6separate hydrating plants and accounted for 80% of commercialsales of quicklime and hydrated lime combined and 73% of total lime production.Domestic lime plant capacity is based on 365 days minus theaverage number of days for maintenance times the average 24-hour capacity of quicklime production, including quicklimeconverted to hydrated lime. In 1998, capacity data wereincomplete, but on the basis of data from 38 plants, the U.S.lime industry operated at about 79% of capacity. Thecalculations do not include combined commercial and captive producers, hydrating plants, plants that commissioned newkilns during the year, and Puerto Rico. This is slightly lower than the operating rate of 81% calculated for 1997. Capacityutilization would be slightly lower if the capacity of several idleor mothballed plants were factored into the calculations. Environment Currently the most common fuel used in lime production iscoal. Emissions generated in the combustion of coal and other fuels makes the lime industry subject to regulation under theClean Air Act. Of concern to the lime industry are the costsand obligations expected for additional monitoring, reporting,and control of hazardous air pollutants such as mercury and particulate matter. Of longer term concern, but with potentiallygreater impacts, are the international discussions on thereduction of greenhouse gas emissions, particularly carbondioxide. Lime production generates carbon dioxide from thecombustion of fuels and from the calcination process, whichdissociates calcium carbonate into calcium oxide and carbondioxide. Any program to regulate carbon dioxide emissionswould affect lime producers. Consumption The breakdown of consumption by major end uses (table 4)was as follows: 39% for metallurgical uses, 26% for environmental uses, 24% for chemical and industrial uses, 9%for construction uses, and 1% for refractory dolomite. Captivelime accounted for about 11% of consumption and was usedmainly in the production of steel in basic oxygen furnaces,sugar refining, and magnesia production. Almost all data oncaptive lime consumption, excluding the sugar industry, werewithheld to protect company proprietary information. As aresult, table 4 simply lists the total quantity and value of lime by end use. End uses with captive consumption are listed infootnote 4 of the table.In steel refining, quicklime is used as a flux to removeimpurities, such as phosphorus, silica, and sulfur. Dolomiticlime is often substituted for a fraction of the high-calcium limeto extend refractory life. Dolomitic quicklime is also used as aflux in the manufacture of glass. The steel industry accountedfor about 30% of all lime consumed in the United States. Limeconsumption by the iron and steel industry was essentiallyunchanged at 6.08 million tons (6.70 million short tons)compared with that of 1997.The lagging steel market was the result of a decrease indomestic steel production caused by a surge in low-valued steelimports beginning in the second quarter of 1998. In 1998,imports of steel mill products increased by 33%, to a record  LIME—199845.3 high of nearly 37.7 million tons (41.5 million short tons). Japan and Russia accounted for 60% of the increase. The surgein imports was the result of very low prices being offered bysome foreign producers, which caused domestic prices to plummet and left U.S. steel companies with large inventoriesand, in a number of cases, severe financial losses (Trickett,1999). The U.S. steel industry and the steelworkers’ unionregistered complaints of foreign dumping of hot-rolled sheetagainst Brazil, Japan, and Russia. In November, the U.S.Department of Commerce (DOC) made a preliminary “criticalcircumstances” finding that could have resulted in duties beingimposed on the material, including any arriving 90 days beforethe DOC published its preliminary antidumping margins(Kelly, 1998). Antidumping duties against Brazilian steel wereavoided with an agreement between the Brazilian Governmentand the DOC that put a quota and a minimum price on hot-rolled steel bound for the United States (Kepp, 1999). On June11, 1999, the U.S. International Trade Commission (ITC) votedunanimously in a final injury determination against hot-rolledimports from Japan. ITC’s duty order will affect all importsentering the United States on or after February 12, 1999. Thefinal antidumping margins were issued earlier by the DOC(Kelly, 1999a). Duties against Russian steel were avoided in anagreement, finalized on July 12, 1999, establishing importquotas and minimum prices on Russian hot-rolled steel. Theagreement eliminates imports of most hot-rolled product for theremainder of 1999; beginning in 2000, annual imports will beallowed to increase gradually to 725,000 tons (800,000 shorttons) by 2003, at which point imports will equal an 80%reduction from those of 1998. Imports of other types of steelfrom Russia were allowed to increase, but the total annualimports will be 2.2 million tons (2.4 million short tons), whichis a significant decrease from the 4.78 million tons (5.27million short tons) of steel mill products exported to the UnitedStates in 1998 (Kelly, 1999b). Antidumping complaints havealso been filed or are being prepared against other types of steel.The increased levels of steel imports were the result of complex factors in international markets. With the onset of therecession in Asia, exports of Russian steel formerly directed tocountries in the Far East were redirected to the United States. Brazil and Japan, each with sagging economies and sinkingcurrencies, tried to improve their situations by exporting product to the largest, strongest market in the world. Ironically, to meet increased demand from customers, someU.S. steel companies were importing steel from these countries. Adding to the problems is that new capacity has continued tocome on-stream in the United States in recent years with more pending.In nonferrous metallurgy, lime is used in the beneficiation of copper ores to neutralize the acidic effects of pyrite and other iron sulfides and to maintain the proper pH in the flotation process. It is used to process alumina and magnesia, to extracturanium from gold slimes, to recover nickel by precipitation,and to control the pH of the sodium cyanide solution used toleach gold and silver from the ore. Such leaching processes arecalled dump leaching when large pieces of ore are involved,heap leaching when small pieces of ore are involved, andcarbon-in-pulp cyanidation when the ore is leached in agitatedtanks. Dump and heap leaching involve crushing the ore,mixing it with lime for pH control and agglomeration, andstacking the ore in heaps for treatment with cyanide solution.Lime is used to maintain the pH of the cyanide solution at alevel between 10 and 11 to maximize the recovery of preciousmetals and to prevent the creation of hydrogen cyanide.The tailings that result from the recovery of precious metalsmay contain elevated levels of cyanides. Lime is used intreatment processes, such as, Cyanisorb, alkaline chlorination,and sulfur dioxide/air, to recover the cyanides.In the environmental sector, lime is used in the softening andclarification of municipal potable water, and to neutralize acidmine and industrial discharges. In sewage treatment, lime’straditional role is to control pH in the sludge digester, whichremoves dissolved and suspended solids that contain phosphates and nitrogen compounds. It also aids clarificationand in destroying harmful bacteria. More recently, the largestuse in sewage treatment has been to stabilize the resultingsewage sludges. Sewage sludge stabilization, also called biosolids stabilization, reduces odors, pathogens, and putrescibility of the solids. In lime stabilization, the basic process involves mixing quicklime with the sludge to raise thetemperature and pH of the sludge to minimum levels for aspecified period of time. Lime consumption for all sludgetreatment increased by 17%. The sewage sludge marketactually decreased by 3%, but the industrial and hazardouswaste market increased by an impressive 85%.In flue gas desulfurization (FGD) systems serving electricutility and industrial plants and incinerators, lime is used toreact with sulfur oxides in the flue gas and is used to stabilizethe resulting sludge before disposal. In 1998, the FGD market bounced back from the slight decrease in 1997 that was caused by mild seasonal temperatures. Bolstered by a 14% increase insales to utility powerplants, the market topped 3 million tonsfor the first time with a total of 3.11 million tons.Lime is used by the pulp and paper industry in the basicKraft pulping process, where wood chips and an aqueoussolution (called liquor) of sodium hydroxide and sodium sulfideare heated in a digester. The cooked wood chips (pulp) aredischarged under pressure along with the spent liquor. The pulp is screened, washed, and sent directly to the paper machine or for bleaching. Lime is sometimes used to producecalcium hypochlorite bleach for bleaching the paper pulp. Thespent liquor is processed through a recovery furnace wheredissolved organics are burned to recover waste heat and wheresodium sulfide and sodium carbonate are recovered. Therecovered sodium sulfide and sodium carbonate are diluted withwater and then treated with slaked lime to recausticize thesodium carbonate into sodium hydroxide (caustic soda) for reuse. The paper industry also uses lime as a coagulant aid inthe clarification of plant process water. In 1998, limeconsumption for pulp and paper production, excluding precipitated calcium carbonate production, decreased by 14%. The pulp and paper industry experienced increased imports andhigh inventory levels, which resulted in decreased pulp production. At the same time, the industry continued makingcapital improvements to recycle as much calcium carbonate  LIME—199845.4 sludge as possible for economic and environmental reasons.Lime is used, generally in conjunction with soda ash, for softening plant process water. This precipitation processremoves bivalent soluble calcium and magnesium cations (and,to a lesser extent, ferrous iron, manganese, strontium, andzinc), which contribute to the hardness of water. This processalso reduces carbonate alkalinity and dissolved solids content.Lime is used to make precipitated calcium carbonate (PCC),a specialty filler used in premium-quality coated and uncoated papers, paint, and plastics. The most common PCC production process used in the United States is the carbonation process.Carbon dioxide is bubbled through milk-of-lime, a suspensionof hydrated lime in water, to form a precipitate of calciumcarbonate and water. The reaction conditions determine thesize and shape of the resulting PCC crystals. Lime demand for PCC production increased by 14%, continuing the stronggrowth exhibited by this market in the 1990's.The chemical industry uses lime in the manufacture of alkalies. Quicklime is combined with coke to produce calciumcarbide, which is used to make acetylene and calcium cyanide. Lime is used to make calcium hypochlorite, citric acid, petrochemicals, and other chemicals.In sugar refining, milk-of-lime is used to raise the pH of the product stream, precipitating colloidal impurities. The limeitself is then removed by reaction with carbon dioxide to precipitate calcium carbonate. The carbon dioxide is obtainedas a byproduct of lime production.In construction, hydrated lime and quicklime are used insubgrade stabilization to stabilize fine-grained soils in place(subgrade) or borrow materials that are employed as subbases,such as hydraulic clay fills or otherwise poor-quality clay andsilty materials obtained from cuts or borrow pits. Lime is alsoused in base stabilization, which includes upgrading thestrength and consistency properties of aggregates that may be judged unusable or marginal without stabilization. Commonapplications for lime stabilization included the construction of roads, airfields, building foundations, earthen dams, and parking areas.Traditionally, most of the lime purchased for stabilization is bought to build and maintain State and Federal roads. Fundingfor these purchases depends on the level of State and Federalroad-building appropriations. Although lime has beenroutinely used for soil stabilization in the United States for decades, its acceptance and usage varies from State to State. Inrecent years, its reputation has spread, which has resulted inincreased usage for road construction in States that previouslyhad only a limited market, and in expanded private sector salesfor use in stabilizing soils at construction sites, such assubdivisions and industrial parks. The strong U.S. economy,good construction weather, and ample State and Federalfunding contributed to the strength of this market in 1998.Sales for soil stabilization increased by 13% compared withthose of 1997.In road paving, hydrated lime is used in hot mix asphalt toact as an antistripping agent. Stripping is generally defined asa loss of adhesion between the aggregate surface and asphaltcement binder in the presence of moisture. Lime is also used incold in-place recycling for the rehabilitation of distressedasphalt pavements. Existing asphalt pavement is pulverized byusing a milling machine, and a hot lime slurry is added alongwith asphalt emulsion. The cold recycled mix is placed andcompacted by using conventional paving equipment, which produces a smooth base course for the new asphalt surface. In1998, sales for use in asphalt increased by nearly 35%.In the traditional building sector, quicklime is used to makecalcium silicate building products, such as sand-lime brick andautoclaved aerated concrete (AAC). AAC offers the advantageof producing building materials that can be cut, drilled, andnailed like wood, but with the advantages of a concrete product.Hydrated lime is used in plaster, stucco, and mortars to improvedurability.Dead-burned dolomite, also called refractory lime, is used asa component in tar-bonded refractory brick used in basicoxygen furnaces. Hydrated lime is used to produce silicarefractory brick used to line industrial furnaces. Prices The average values per ton of lime rounded to threesignificant figures are discussed in dollars per metric ton withaccompanying conversions into dollars per short ton. For accuracy, the conversions were made from the unroundedmetric value and, as a result, may not be an exact conversion of the rounded values. All value data for lime are reported by typeof lime produced—high-calcium quicklime, high-calciumhydrate, dolomitic quicklime, dolomitic hydrate, and dead- burned dolomite. Emphasis is placed on the average value per ton of lime sold.In 1998, prices were essentially unchanged from those of 1997, with the few exceptions mentioned below. The averageunit value per ton of all lime sold or used by producers, on anf.o.b. plant basis, was $60.50 ($54.90 per short ton). Theaverage values per ton of lime sold and used, by type of lime,were $57.60 ($52.30 per short ton) for quicklime, $78.90($71.60 per short ton) for hydrated lime, and $87.80 ($79.60 per short ton) for refractory dolomite.The average value per ton of quicklime sold was $57.00($51.70 per short ton). The average value per ton of high-calcium quicklime sold was $56.90 ($51.70 per short ton). Theaverage value per ton of dolomitic quicklime sold increased bynearly $1.00 to $57.30 ($52.00 per short ton). The averagevalue per ton of refractory dead-burned dolomite sold was$87.30 ($79.20 per short ton).The average value per ton of hydrated lime sold decreasedslightly to $79.60 ($72.30 per short ton). The average value per ton of high-calcium hydrate sold was $75.40 ($68.40 per short ton). The average value per ton of dolomitic hydrate solddecreased by about $4.00 to $100.70 ($91.40 per short ton). The high dolomitic hydrate value is characteristic of high-valuespecialty products, such as mason’s lime, which is moreexpensive to manufacture (requires pressure hydration) and isfrequently shipped in bags. Foreign Trade The United States imported and exported quicklime,
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