Phosphate rocks impacts

This paper results from work completed in 1979 (and updated in 1980) to evaluate the emerging supply/demand, cost/price outlook for the fertilizer commodities phosphate rock, upgraded phosphates, sulfur, and sulfuric acid. Our purpose here is to publish, in part, our analysis of recent trends and events which impact on sulfur supply and demand, and to use these together with available production cost data to project price behavior for sulfur over the near term. Such projections are helpful to managers of large industrial firms as one of several tools available to them in making investment, contract, marketing, or other major decisions. This paper is necessarily limited in scope, and will attempt to summarize the world outlook with emphasis on the North American scene. 

Herring, J. R., and Fantel, J. R., Phosphate Rock Demand into the Next Century Impact on World Food Supply, Nonrenewable Resources, 2(3), 226-241 (1993). 

Measuring and Estimating the Impact of Phosphate Rock Quality Factors.lH... 

Contaminants of Concern - All phosphate ore contains traces of radioactive elements, and some contain a number of metals. These impurities are studied in relation to their impact on health and the environment. During the processing of the phosphate rock they are partitioned between ore beneficiation process waste, add process waste, and final product. 

J.R. Lehr, Impact of phosphate rock quality on market use, Industr. Miner., May 1984. 

The annual impact of shifting all the pig herd in Denmark to a phytase supplemented diet instead of MCP supplemented would be a reduction in greenhouse gases by 27 kT CO2 equivalent, reduction in acidification by 450 T SO2 equivalent, reduction in nutrient enrichment by 1200 T phosphate equivalent, and avoiding mining of 20 kT phosphate bearing rock. 

Here [Mp] and [Mr] are the metal concentrations in particulate matter and in crustal rock, respectively, and [Alp] and [Ah] are the concentrations of aluminum (or any suitable reference element) in particulate matter and crustal rock, respectively. Table 3 lists EEs for SPM or fine sediment in contrasting estuaries. Enrichment factors are close to unity for the baseline sediment and in the pristine Lena Estuary, while the greatest EE values are encountered for cadmium in the Rhine (impacted by the production of phosphate fertilizers) and the Scheldt, and for copper in Restronguet Creek (impacted by historical mining activity). The general sequence of EEs... 

Phosphorites are reported to have high concentrations of Cd up to 980 mg kg (Table 1). Even though on a world-area basis, outcrops of phosphorites are of little significance, the environmental impact of Cd in these rocks is likely to be much greater than that in black shales because phosphorites are the major source of phosphate for agricultural fertilizer manufacture. Some of the phosphate fertilizers are reported to contain 140 mg Cd kg (Idaho monoammonium... 

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