Waste rock

Calcium sulfate is the essential component of plaster and sheet rock. Waste calcium sulfate can be converted into quicklime, CaO, by reaction with carbon at high temperatures. The following two reactions represent a sequence of reactions that might take place ... [Pg.116]

Significant volumes of earth must be displaced to mine coal coal mines and the resulting rock waste can disrupt the environment. Furthermore, burning coal releases environmentally harmful chemical compounds into the air. [Pg.731]

The movement downslope as a viscous flow of saturated rock waste is referred to as solifluctbn. It probably is the most significant process of mass wastage in tundra regions. Such movement... [Pg.125]

There are three types of wind erosion, namely, deflation, attrition and abrasion. Deflation results in the lowering of land surfaces by loose unconsolidated rock waste being blown away by the wind. The effects of deflation are seen most acutely in arid and semi-arid regions. For example, basin-like depressions are formed by deflation in the Sahara and Kalahari deserts. [Pg.127]

About one-fifth of the land surface of the Earth is desert. Approximately four-fifths of this desert area consists of exposed bedrock or weathered rock waste. The rest is mainly covered with deposits of sand. Bagnold (1941) recognized five main types of sand accumulations, namely, sand drifts and sand shadows, whalebacks, low-scale undulations, sand sheets and true dunes. He further distinguished two kinds of true dunes, the barkhan and the seif (Fig. 3.33a and b). [Pg.128]

The UOC is dried and packed in metal drums and marketed, that is, sent to the UCF. The remainder of the ore, containing most of the radioactivity (from uranium progenies) and nearly all the rock waste material, becomes mine tailings that are placed in storage facilities near the mine. The tailings usually contain low... [Pg.28]

The ore is initially crushed from rock matrix to mineral grain size or smaller. Often this rock powder is mixed with water and/or chemical reagents to form slurry. This mixture is injected with air and agitated by stirring. The mineral particles then attach themselves to air bubbles and float off as a concentrate, while the wet grains of rock (waste) sink to the bottom. [Pg.216]

Synthetic covers are expensive and susceptible to cracking after installation due to desiccation or subsidence. The effectiveness of such covers relies on long term integrity and because they are located on the tailings surface they are most susceptible to erosion (Blowes et al. 1994). The strategy is only applicable to rock waste, spoil or backfill and not to in situ rock (Robertson 1987). [Pg.224]

Pb/Zn mining <500mgkg CdS (with ZnS) rock waste, tailings, soils... [Pg.245]

Hg/Cu/Zn mining, extraction HgS mining tailings, rock waste, soils, smelting slags, dusts, soils... [Pg.246]

Metal mining, esp. Cu, Zn, Pb, Sn up to 3.6% tailings and rock waste AsS, FeAsS soils around tailings... [Pg.247]

Mining of Cr <50% PbCr04, FeCr204 rock waste, tailings... [Pg.248]

Mining Pb, Zn etc. <15% <5000 mg kg" PbS, PbS04, PbCOj rock waste, tailings soils... [Pg.249]

Mining CuFeSa, CusFeS4, CU2S, CU3ASS4, CuS, Cu, cyanides ZnS, in crushed rock wastes <5% (Ni, Fe)9Sg, NiAs, (Cu, NO3S4... [Pg.250]

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...