摘要
铜绿山古铜矿冶遗址是我国最重要的矿冶遗迹，以往的研究认定其开采的是氧化矿石，使用的冶炼技术是氧化矿石直接还原冶炼成铜。这一结论主要是根据铜绿山矿区赋存有大量的氧化矿石，考古发掘的古矿井位于氧化带并出土有氧化矿石等事实获得的，并因用铜绿山氧化矿石进行的模拟实验成功地炼出铜而得到强化。为复原冶炼技术对ＸＩ矿体上的炉渣堆积进行的发掘，获得了炼炉和大量层位清楚的炉渣样品，但对这些样品的分析是在冶炼氧化矿石的结论之下进行的，最能反映冶炼性质的炉渣分析数据未被充分利用来确定矿石和产品类别。本文根据铜冶金基本原理对ＸＩ矿体炉渣所代表的冶炼过程的性质提出了疑问，进而建立通过炉渣分析判定冶炼过程的方法，并以此方法配之以模拟实验对铜绿山ＸＩ矿体和动力科仓库院内的古炉渣进行了研究，认定前者是冶炼品位为６５％的冰铜的炉渣，后者才是真正的直接冶炼氧化矿石成铜的炉渣。
Previous researches suggested only oxide ores were smelted directly to copper in the ancient time at Tonglushan.This conclusion was mainly based on the fact that Tonglushan copper mine is very rich in oxide ores.However,the reported analyses data of slag from XI ore body are not fit for the characters of the slag produced from the smelting of oxide ores directly to copper,i.e.,the content of sulphur in the slag is too high to keep the sulphur equilibrium between the ores and the slags. In order to recover the smelting technology symbolized by the slag from XI ore body,a model is built based on the analyses of slags. Slags can be distinguished by the existing form of copper in the slag and the ratio of copper to sulphur,or Cu/S,of the slag. Only matte prills can be found in matte-slag (referring to that the smelting product is matte). The composition of prills larger than 50μm is close to that of matte.In copper-slag (referring to that smelting product is copper) pure copper prills can be found easily.White matte (Cu 2S) prills can also be found together with copper prills or independently in small amount. The Cu/S of matte-slag is below 4.The relationship between matte grade and Cu/S of matte-slag can be expressed as a formula: Cu%=161P((44Cu/S-11)+20 Where P=K-n(K-1) K demonstrates the rate of the dissolution of FeS and Cu 2S in matte-slag, n is the percentage of the copper in the mechanically entrained matte to the total copper in matte-slag. As a constant determined half by the composition of slags and half by the operation of smelting,K can be measured through experiments. The Cu/S ratio of copper-slag is above 4. Sixty four slag samples from 2 sites of Tonglushan including XI ore body have been studied by the model above with chemical and SEM analyses (see the table).The average analysis data of slag samples from Tonglushan Name of siteNumber of samplesChem AnalCu%S%Cu/SSEM AnalFeO%SiO 2%Al 2O 3%CaO%K 2O%[BHDG2,WK8ZQ0,WK5,WK3。3,WK1,WK4。5W]XI ore body520.610.381.6151.933.48.93.81.0Donglike120.780.01745.841.742.911.71.91.0 The slag samples of XI ore body are matte-slag.The average matte grade is suggested to be about 65% by the SEM analyses of big prills in the slag and the calculation through the formula above with the help of experiments to measure the constant P. The slag samples of Donglike belong to the copper-slag with the Cu/S much bigger than 4. They are the true slag of reducing smelting of oxide ores. The present studies show that the matte smelting technique was used as early as the period of Warring States (475～221BC)
出处
《有色金属》
CSCD
1998年第3期120-128,共9页
Nonferrous Metals
