『Summary
The demand for biofuels has recently increased because of rising
prices of fossil fuels and diversification of energy resources.
As a result, the demand for sugarcane and corn has been increasing,
not only for food production, but also as sources of energy. In
this context, securing supplies of phosphorus, required as an
essential nutrient in agricultural production, has considerable
implications that extend beyond food and agricultural policy.
It is therefore important to consider the quality and availability
of phosphorus resources that remain untapped, because the demand
and supply of phosphorus ore is currently becoming very tight,
and Japan has no domestic phosphorus resources.
To identify potential phosphorus resources, we have investigated
the material flow of phosphorus within Japan, including that in
the iron and steel industry, on the basis of statistical data
for 2002. Our major finding is that the quantity of phosphorus
in iron and steelmaking slag is almost equivalent to that in imported
phosphate ore in terms of both the amount and concentration. We
also found, by means of a waste input-output analysis and a total
materials requirement study, that the phosphorus potentially recoverable
from steelmaking slag by a new process that we have proposed has
considerable environmental and economic benefits. Concerning the
restricted supplies of phosphorus resource, it is important to
consider the quality and availability of phosphorus resources
that currently remain untapped. From that viewpoint, steelmaking
slag would be expected to be a great potential resource for phosphorus.
Keywords: industrial ecology; input-output analysis (IOA); phosphate;
slag; substance flow analysis (SFA); steelmaking』
Introduction
Material/substance flow of phosphorus in Japan
Agriculture, livestock, and fishery sectors
Crops and livestock
Meat, oils, and marine products
Human activity and farming and ranching
Summary of the agriculture, livestock, and fishery sectors
Industrial sectors
Mineral resources
The chemical industry
The fertilizer industry
The iron and steel industry
Other industry
Summary of industrial activity
Waste treatment and environmental sectors
Human excrement treatment sector
Wastewater sector
Sewage treatment and sludge sector
Environmental sectors
Summary of the waste-treatment and environmental sectors
Domestic substance flow of phosphorus in Japan
Environmental effects of phosphorus recovery
Recovery of phosphorus from iron and steelmaking slag
Waste input-output analysis
Discussion and conclusion
Acknowledgments
Notes
References
 Figure 15 Overall domestic material flows of phosphorus in Japan, in kilotons of phosphorus (kt-P). Matsubae-Yokoyama,K., Kubo,H., Nakajima,K. and Nagasaka,T.(2009): A material flow analysis of phosphorus in Japan The iron and steel industry as a major phosphorus source. Journal of Industrial Ecology, 13(5), 687-705.から |