Copper Concentrate: Sulphide Ore Stamped, Jigged and Tabled at the Anaconda Mill (Richards, Ore Dressing 1903)

Copper sulphide ore is too lean to smelt as mined. At the Anaconda mill it was screened, crushed under steam stamps, sorted by settling speed in rising water, and run over jigs and slime tables, where the heavy copper minerals sink and the light quartz and feldspar wash away. Result: concentrates of 12 to 20 % copper; 100 tons of ore gave 50 to 75 tons. The mill handled 2,500 to 2,700 tons a day. Source: Robert H. Richards, Ore Dressing vol. II (1903), pp. 984-986, Mill No. 42, Anaconda Copper Mining Company. Not given: the copper in the ore, water per ton. Picture drawn by Youblob.

متقدم

1 day

التعليمات

Sort the ore

In the mine, pick the ore by hand into rich ore (straight to the smelter), hard concentrating ore and soft concentrating ore. The ore holds chalcocite, chalcopyrite, pyrite, enargite and blende in quartz and decomposed feldspar; the aim is to save the copper and silver without the zinc.

المواد لهذه الخطوة:

خام النحاس الكبريتيدي100 tons

Screen and pick

Pass each kind over vibrating grizzlies with 1 in spaces; hand-pick the oversize for rich ore. Screen the undersize in trommels: 6.35 mm round holes for hard ore; 12.7 mm then 6.35 mm for soft ore.

الأدوات المطلوبة:

غربال تصنيف

غربال أسطواني دوّار

Crush under steam stamps

Crush the coarse hard ore under steam stamps with screens of 4.76 x 9.52 mm slots, the soft ore under stamps with 12.7 mm round holes. Richards notes that steam stamps were later given up for these ores.

الأدوات المطلوبة:

مطحنة الدقّ

ماء

Classify and jig

Jig the coarse soft ore on 1-sieve Harz jigs. Send all fine ore to hydraulic classifiers with three spigots; each spigot feeds its own row of 2-sieve Collom jigs. The heavy concentrate is drawn from the jigs; middlings are crushed again.

الأدوات المطلوبة:

مهزّة الخام (جِغ)

مصنِّف هيدروليكي

ماء

Table the slimes and collect

Run the classifier overflow over convex revolving slime tables. Gather all concentrates and settlings for the smelter: 12 to 20 % copper, 50 to 75 tons from 100 tons of ore. Tailings keep 1 1/4 to 2 % copper.

الأدوات المطلوبة: