4
Phytomining Applied for Postmining Sites
Hermann Heilmeier
Abstract
The economics associated with establishing and growing vegetation at
contaminated sites can be improved if a metal that has commercial value
can be extracted from the soil by plants. Phytomining is the process of
extracting a product such as nickel from soil using hyperaccumulator
plants that are able to grow in the contaminated soil and accumulate a
metal product of value. After harvesting the plant biomass, drying it,
and burning it for energy recovery, the ash can be processed to extract
the metal of interest. Nickel and gold are good examples of products
that have commercial value when phytomining is implemented at a contaminated site. Solar energy is used in phytomining, and soil quality is
improved in many cases by increasing soil organic carbon and improving biological health and diversity in the soil. This chapter includes a
review of phytomining and an analysis of its applications at contaminated sites containing metals that have commercial value.
CONTENTS
4.1 Introduction.................................................................................................. 61
4.2 Advantages and Limitations of Phytomining ......................................... 62
4.3 Field Experiments on Phytomining ..........................................................64
4.4 Agronomic Practices....................................................................................64
4.5 Economic Viability and Environmental Considerations ....................... 66
4.6 Options for Commercial Application of Phytomining .......................... 68
4.7 Conclusions and Perspectives.................................................................... 69
References............................................................................................................... 70
4.1 Introduction
Phytomining uses the capacity of plants and their associated microorganisms to extract and accumulate trace elements at high concentrations in their
(above-)ground biomass (phytoextraction). However, in contrast to applications of phytoextraction for removing toxic trace elements (e.g., heavy metals,
61
Phytomining Applied for Postmining Sites
Hermann Heilmeier
Abstract
The economics associated with establishing and growing vegetation at
contaminated sites can be improved if a metal that has commercial value
can be extracted from the soil by plants. Phytomining is the process of
extracting a product such as nickel from soil using hyperaccumulator
plants that are able to grow in the contaminated soil and accumulate a
metal product of value. After harvesting the plant biomass, drying it,
and burning it for energy recovery, the ash can be processed to extract
the metal of interest. Nickel and gold are good examples of products
that have commercial value when phytomining is implemented at a contaminated site. Solar energy is used in phytomining, and soil quality is
improved in many cases by increasing soil organic carbon and improving biological health and diversity in the soil. This chapter includes a
review of phytomining and an analysis of its applications at contaminated sites containing metals that have commercial value.
CONTENTS
4.1 Introduction.................................................................................................. 61
4.2 Advantages and Limitations of Phytomining ......................................... 62
4.3 Field Experiments on Phytomining ..........................................................64
4.4 Agronomic Practices....................................................................................64
4.5 Economic Viability and Environmental Considerations ....................... 66
4.6 Options for Commercial Application of Phytomining .......................... 68
4.7 Conclusions and Perspectives.................................................................... 69
References............................................................................................................... 70
4.1 Introduction
Phytomining uses the capacity of plants and their associated microorganisms to extract and accumulate trace elements at high concentrations in their
(above-)ground biomass (phytoextraction). However, in contrast to applications of phytoextraction for removing toxic trace elements (e.g., heavy metals,
61