4.5.1.1 Resources and Reserves

Sulfur resources are very abundant in China. In this section total sulfur resources include sulfur reserves and potential resources. Sulfur reserves refer to reserves of pyrite, by-product pyrite and native sulfur explored through geological exploration; sulfur potential resources include the unexplored part of resources of sulfur recoverable from oil, natural gas, nonferrous metal sulfides, coal, oil shale, gypsum, anhydrite, alunite and arsenic and out-of-balance reserves of pyrite. It is estimated that China's total sulfur resources amount to 13 billion tons. By 1997 the retained sulfur reserves were 1.451 billion tons, accounting for 11.2% of the total resources, and the sulfur potential resources make up over 88%. The potential resour-ces of sulfur in coals and gypsum of China are enormous. Only sulfur in coals accounts for over 74% of the potential resources; sulfur in gypsum is second with about 11.4% of the potential resources; sulfur in nonferrous metals, oil, natural gas and alunite and the out-of-balance reserves of pyrite etc. together constitute 3.4%.

By 1997, China had possessed 747 sulfur mining areas with retained sulfur reserves of 1.451 billion tons, of which pyrite sulfur reserves were 806 million tons, accounting for 55.6% of the total, by-product pyrite sulfur reserves were 324 million tons, accounting for 22.3% of the total, and native sulfur reserves were 321 million tons, taking up 22.1% of the total.

Sulfur resources in the world are very rich. According to the Mineral Commodity Summaries, 1997, the world's sulfur reserve base was 3.5 billion tons. China's categories A+B+C reserves may be largely compared with the world's reserve base. China's retained sulfur reserves of categories A+B+C as of 1997 were 386 million tons; it ranked second, following Iraq.

4.5.1.2 Characteristics of Resources

(1) Geographical distribution

Up to the end of 1997, except Shanghai, Tianjin and Hong Kong which have no explored sulfur reserves, the other thirty provinces (regions and municipalities) have a total of 747 sulfur occurrences with retained sulfur reserves of 1.451 billion tons (the sulfur reserves and occurrences of Taiwan are excluded for lack of the data). The retained sulfur reserves include those of pyrite, by-product pyrite and native sulfur.

Pyrite reserves are distributed in 28 provinces (regions and municipalities). There are 484 pyrite occurrences with retained ore reserves of 4.408 billion tons (equivalent to 850 million tons of sulfur on the basis of the average S grade of 18.24%). The reserves are mainly concentrated in the Southwest, South-central and East China administrative megaregions. The reserves of the three megaregions account for about 80% of the total sulfur reserves. In terms of provinces (regions), the reserves are mainly distributed in Sichuan, Anhui, Guangdong, Inner Mongolia, Yunnan, Guizhou, Jiangxi, Shanxi, Henan and Hunan.

By-product pyrite is distributed in 26 provinces (regions and municipalities). There are 253 mining areas with retained sulfur reserves of 324 million tons. They are mainly concentrated in Jiangxi, Shaanxi, Gansu, Jilin, Anhui and Yunnan, of which Jiangxi contributes the most abundant reserves of by-product pyrite, 27.82% of the total by-product pyrite reserves.

Native sulfur is distributed in Shandong,Tibet, Qinghai and Xinjiang, where there are 10 mining areas with retained sulfur reserves of 321 million tons. Among these mining areas, the Zhujiazhuang mining area, Tai'an, Shandong, and the Dawenkou mining area, Shandong, are largest in scale with retained sulfur reserves of 311 million tons, 99.62% of the total native reserves. The distribution and index of large and medium-sized occurrences of various kinds of sulfur-bearing ore in China are presented in Fig. 4.5.1.

(2) Characteristics of resources

     1) There is an appreciable contrast between China's sulfur resources and the world's sulfur resources in respect to the structure. In the structure of the world's sulfur resources, sulfur in oil and natural gas constitutes a large proportion and is the main source of sulfur. In contrast to the world's sulfur resources, China's oil is mostly low-sulfur and sour natural gas mainly occurs in a gas field in the vicinity of Weiyuan, Sichuan, and moreover the total sulfur resources in soil and gas account for only 0.12% of China's sulfur potential resources. On the contrary, China's pyrite resources rank first in the world, being by far more abundant than those in other countries in the world. Besides pyrite as an ore of sulfur alone and as a by-product in ores containing other metals, sulfur in coal measures also occurs in the form of pyrite. Only the three parts of pyrite contribute 83.4% of sulfur resources of China.

   2) Various genetic types of sulfur deposits.On the basis of the origin of sulfur, sulfur deposits in China may fall into four major types: sedimentary pyrite deposits in coal-bearing or coal-barren strata, native sulfur and sour natural gas deposits in evaporate basins, continental volcanic-pneumato-hydrothermal deposits and submarine volcanic deposits. Of these, submarine volcanic deposits have great significance; the examples are large pyrite deposits such as the Dajiangping deposit, Guangdong, and the Dongshengmiao deposit, Inner Mongolia.

   3) More high-grade ore and less low-grade ore.Up to 1996, China's pyrite ore reserves reached 4.634 billion tons. The I-grade ore with the sulfur grade >35% accounts for 3.7% of the pyrite ore reserves only, that is to say, 96.3% of pyrite ore belongs to medium- and low-grade ores with 12 to 35% sulfur, of which the low-grade ore with 12 to 20% sulfur occupies a relatively large proportion. The average sulfur grade of the pyrite ore is <20%.

Fig. 4.5.1Distribution of sulfur deposits in China

Index of sulfur occurrences: 1. Pyrite ore in the Karatongk No. 1 copper-nickel deposit, Fuyun County, Xinjiang; 2. Jiashengpan lead-zinc-sulfur deposit, Urad Middle Banner, Inner Mongolia; 3. Shanpiangou pyrite deposit, Urad Front Banner, Inner Mongolia; 4. Duimenshan sulfur-zinc deposit, Urad Middle Banner, Inner Mongolia; 5. pyrite ore in the Dongshengmiao polymetallic ore mining area, Urad Rear Banner, Inner Mongolia; 6. pyrite ore in the Tanyaokou polymetallic ore mining area, Urad Rear Banner, Inner Mongolia; 7. pyrite deposit at Qingyuan County, Liaoning; 8. Hongtoushan copper deposit (by-product sulfur), Qingyuan County, Liaoning; 9. Jinjia pyrite deposit, Benxi County, Liaoning; 10. Yunpan pyrite deposit, Benxi County, Liaoning; 11. Zhangjiagou pyrite deposit, Fengcheng County, Liaoning; 12. Beishan pyrite deposit, Bajiazi, Jianchang County, Liaoning; 13. Liukuidi pyrite deposit, Yingkou County, Liaoning; 14. Qiancuoluo molybdenum deposit, Daheishan, Yongji County, Jilin; 15. Jiadaogou pyrite deposit, Yongji County, Jilin; 16. Xitaizi pyrite deposit, Huadian City, Jilin; 17. Qinglongtan pyrite deposit, Serteng Mountain, Qinghai; 18. Dur'ngoi copper-cobalt deposit (by-product sulfur), Maq¨ºn County, Qinghai; 19. Xitieshan lead-zinc mining area (by-product sulfur), Qaidam, Qinghai; 20. Baijiazuizi copper-nickel deposit (by-product sulfur), Yongchang County, Gansu; 21. Baiyinchang pyrite copper-lead-zinc deposit (by-product sulfur), Baiyin City, Gansu; 22. Xiaotieshan polymetallic ore deposit (by-product sulfur), Baiyin Citym Gansu; 23. Changba lead-zinc deposit (by-product sulfur), Chengxian County, Gansu; 24. Jinduicheng molybdenum deposit (by-product sulfur), Huaxian, Shaanxi; 25. Huanglongpu molybdenum deposit (by-product sulfur), Luonan County, Shaanxi; 26. Jingangku pyrite deposit, Wutai County, Shanxi; 27. Shenshuigou mining area, Yangquan City, Shanxi; 28. Shuohuang mining area, Pingding County Shanxi; 29. Liujiashan mining area, Changzhi County, Shanxi; 30. Zhouchun mining area, Jincheng City, Shanxi; 31. Beiliu mining area, Yangcheng County, Shanxi; 32. Gaobanhe lead-zinc-pyrite deposit, Xinglong County, Hebei; 33. Xingshutai pyrite deposit, Neiqiu County, Hebei; 34. Sanwangcun cobalt- and copper-bearing pyrite deposit, Shahe City, Hebei; 35. Zhujiazhuang native sulfur mining area, Tai'an Shandong; 36. Diaoyutai pyrite deposit, Qibaoshan, Wulian County, Shandong; 37. Fengcun pyrite deposit, Jiaozuo City, Henan; 38. Zhuyuan-Kuangkou pyrite-bauxite deposit, Xin'an County, Henan; 39. Yinjiagou pyrite deposit, Lingbaoshan, Henan; 40. Nannihu molybdenum (tungsten) deposit (by-product sulfur), Luanchuan County, Henan; 41. Huangchangping pyrite deposit; Jianshi County, Hubei; 42. Xianju pyrite deposit, Jingmenshan, Hubei; 43. Jianyanhe pyrite deposit, Zhicheng City, Hubei; 44. Tonglushan copper-iron deposit (by-product sulfur), Dazhi County, Hubei; 45. Tieshan pyrite deposit, Xinyu County, Jiangxi; 46. Wushan copper-sulfur-iron mining area (by-product), Ruichang County, Jiangxi; 47. Chengmenshan copper-sulfur-iron mining area (by-product sulfur), Jiujiang City, Jiangxi; 48. Dexing copper mine (by-product sulfur), Jiangxi; 49. Yinshan lead-zinc-copper mining area (by-product sulfur), Dexing County, Jiangxi; 50. Fenglin copper mining area (by-product sulfur), Dongxiang County, Jiangxi; 51. Tianbaishan copper-sulfur mining area (by-product sulfur), Yongping, Qianshan County, Jiangxi; 52. Qingtang pyrite mining area, Ningdu County, Jiangxi; 53. Xiqiu copper deposit (by-product), Shaoxing City, Zhejiang; 54. Xikouhe pyrite deposit, Longyou County, Zhejiang; 55. Anjishan copper mining area (by-product sulfur), Jiangxing County, Zhejiang; 56. Yuntaishan pyrite deposit, Jiangning County, Zhejiang; 57. Meishan iron deposit (by-product sulfur), Nanjing City, Jiangsu; 58. Xiangshan pyrite deposit, Ma'anshan City, Anhui; 59. Mashan pyrite deposit, Ma'anshan City, Anhui; 60. Xiaoling pyrite deposit, Hejia, Lujiang County, Anhui; 61. Luohe iron deposit (by-product sulfur), Lujiang County, Anhui; 62. Dabaozhuang iron-pyrite deposit, Lujiang County, Anhui; 63. Xinqiao copper-pyrite deposit, Tongling County, Anhui; 64. Dongguashan copper deposit (by-product sulfur), Tongling City, Anhui; 65. Chimenkou pyrite deposit, Qingyang County, Anhui; 66. Yinzhushan pyrite deposit, Huaining County, Anhui; 67. Pingfeng sulfur-lead-zinc mining area, Pucheng County, Fujian; 68. Shacha sulfur polymetallic ore deposit, Datian County, Fujian; 69. Qibaoshan copper polymetallic ore deposit (by-product sulfur), Liuyang County, Hunan; 70. Hongshuiping pyrite deposit, Xinhua County, Hunan; 71. Putou pyrite deposit, Chengbu County, Hunan; 72. Shuikoushan lead-zinc deposit (by-product sulfur), Changning County, Hunan; 73. Yangjiayuan pyrite deposit, Jiangyou City, Sichuan; 74. Sanhuangchang, Qinglong, Fengji County, Chongqing; 75. Zhoujia, Xianfeng, Xingwen County, Chongqing; 76. Deganba, Xianfeng, Xingwen County, Chongqing; 77. Xintang, Xianfeng, Xingwen County, Chongqing; 78. Gusong, Xingwen County, Chongqing; 79. Xinhua, Xianfeng, Xingwen County, Chongqing; 80. Hongqiao No. 5 mine (Fu'an mine field), Jiang'an County, Chongqing; 81. Dashu, Xuyong County, Chongqing; 82. Duchuanpo, Xuyong County, Chongqing; 83. Shiping, Gulin County, Chongqing; 84. Tianfu, Beibei, Chongqing; 85. Hongtoushan copper deposit (by-product sulfur), Zhongdian, Yunnan; 86. Jinding lead-zinc deposit (by-product sulfur), Lanping, Yunnan; 87. Xincun, Luquan County, Yunnan; 88. Yujialaochang, Fuyuan, Yunnan; 89. Chetu pyrite deposit, Luoping, Yunnan; 90. Shunhe, Weixin, Yunnan; 91. Heishuzhuang, Zhenxiong, Yunnan; 92. Mijiang mining area, Renhuai County, Yunnan; 93. Buzhengba mining area, Zunyi County, Guizhou; 94. Shimianshan mining area, Zunyi County, Guizhou; 95. Sanchahe mining area, Zunyi County, Yunnan; 96. Liangshuijing mining area, Meitan County, Guizhou; 97. Linkou mining area, Biji County, Guizhou; 98. Wangjiaba mining area, Biji County, Guizhou; 99. Yunlong mining area, Dafang County, Guizhou; 100. Maochang mining area, Dafang County, Guizhou; 101. Jinpo-Yanzidong mining area, Zhongzhai, Qianxi County, Guizhou; 102. Beishan lead-zinc-pyrite mining (by-product sulfur), Huanjiang County, Guangxi; 103. Tongkeng tin-lead-zinc mining area (by-product sulfur), Dachang, Nandan County, Guangxi; 104. Hangdong pyrite mining area, Fengshan County, Guangxi; 105. Longhua pyrite mining area, Jingxi County, Guangxi; 106. Yangliutang mine, Lechang, Guangdong; 107. Fankou lead-zinc deposit (by-product sulfur), Renhua County, Guangdong; 108. Dabaoshan polymetallic ore deposit (by-product sulfur), Qujiang County, Guangdong; 109. Hongyan pyrite deposit, Yingde County, Guangdong; 110. Xiniu pyrite mining area, Yingde County, Guangdong; 111. Dajiangping pyrite deposit, Yunfu County, Guangdong; 112. Shibankeng pyrite deposit, Yunfu County, Guangdong; 113. Heishigang pyrite deposit, Yangchun County, Guangdong; 114. Guantian pyrite deposit, Haifeng County, Guangxi; 115. Ruifang pyrite deposit, Jilong, Taiwan

The grades of by-product pyrite are highly varied. It generally ranges from 10% to 30% with an average of 3.67% and may reach a maximum of 42.78% and a minimum of 1.5% to 3.0%. The sulfur grade in native sulfur deposits is commonly low, being about 10%.

    4) Presence of many useful components.Most of China's pyrite deposits contain many useful components. For example, in skarn, hydrothermal and volcanic deposits, sulfur is associated with such base, noble and rare-dispersed elements as copper, lead, zinc, molybdenum, gold, silver, cobalt, gallium, selenium, tellurium, gadolinium, cadmium and tho-rium; in sedimentary deposits there are also such minerals as iron, manganese, coal, bauxite and clay in addition to pyrite. This condition is favorable for multi-purpose exploitation, recovery and utilization. Some ores contain slightly high contents of impurities such as arsenic and mercury, which are harmful to the production of sulfuric acid.

   5) Poor production conditions.The great majority of China's pyrite deposits need underground mining. Ore reserves suitable for underground mining account for about 65% of the total pyrite ore reserves, while the ore reserves that have good mining conditions and suitable for open-cut mining only about 15%. At present, only the pyrite ores at shallow parts of a few mining areas such as the Dajiangping mining area, Yunfu, Guangdong, the Hongyan mining area, Yingde, Guangdong, and the Mashan mining area, Anhui, can be open-cut-mined. About half of the by-product pyrite ores are suitable for open-cut mining.

   6) Good dressibility.The principal pyrite ore dressing method used in China now is floatation, and in a few cases gravity dressing is also used. According to the dressing tests of pyrite ores from metamorphosed sedimentary, coal-measures sedimentary and hydrothermal fissure filling-replacement deposits, to concentrate pyrite ores into those with a sulfur grade greater than or equal to 35% is technically feasible and will yield good social and economic benefits, and meanwhile useful elements such as copper, gold and silver can also be recovered and transportation costs may be reduced.