Posted on March 11, 2020 by Robert Uram
Two promising new technologies—recovery of rare earths from acid mine drainage (AMD and conversion of AMD treatment by-products to paint pigments are bringing new hope to remediating AMD polluted streams. These technologies are a kind of modern day alchemy—restoring streams that are orange and lifeless by turning pollution into economically valuable products and creating new jobs for local economies. The development of economically viable treatment processes is a game changer for AMD treatment with potentially huge benefits for national security, local economies, and restoration of the health of thousands of miles of now lifeless streams.
Rare Earth Recovery
West Virginia University’s Water Research Institute director, Paul Ziemkiewicz, PhD, has been at the forefront of researching AMD issues and developing AMD remediation techniques for decades. Dr. Ziemkewicz has developed a process that can extract rare earths from AMD. As explained more fully in Rare Earths Funded, last fall he received a 5 million dollar grant from the Department of Energy to build a pilot plant in conjunction with the WVDEP that will extract rare earths while treating 500 gallons of AMD per minute. Dr. Ziemkewicz estimates that AMD flows could be the source of as much as 2200 tons of rare earths a year.
Rare earths are a critical component in many products including cell phones. Rare Earths Funded explains that, “Rare earth metals consist of the 17 chemically similar elements at the bottom of the periodic table, such as cerium and scandium. Despite their name, they’re not “rare” because they’re often found in other minerals, within the earth’s crust or, in this case, in coal and coal byproducts.” Most of the 20,000 tons of rare earths we use are imported, mainly from China. The initial plant will be located on Abrams Creek, a tributary to the North Branch of the Potomac River and will benefit at least 17 miles of stream.
Rural Action is a watershed organization that has been involved in restoring AMD damaged streams since 1991. Recently, they have partnered with Ohio University Professor Guy Riefler, and the Ohio Department of Natural Resources to develop a process that transforms iron from AMD into marketable paint pigments in a process called True Pigments, https://www.ohio.edu/news/2019/12/acid-mine-drainage-cleanup-plant-moves-closer-full-scale-thanks-3-5m-award. They have received a 3.5 million dollar grant from the OSMRE to partially fund the development of a treatment plant. The initial plant will treat a large discharge in the Sunday Creek watershed in Athens County, Ohio, that pollutes a seven-mile stretch of Sunday Creek with 2.2 million pounds of iron each year.
The True Pigments process treats polluted water, removing iron oxide, to yield a commercial grade of iron pigment, which can be used in paint production. The United States uses about 224,000 tons of paint pigment each year, most of which is imported from China. The first True Pigments plant is anticipated to meet one percent of that supply. Rural Action is still seeking an additional four million dollars needed to build the treatment facility.
In the past 25 years, with the active support of dozens of watershed groups like Rural Action and Friends of the Cheat River in West Virginia and state and federal agencies, hundreds of projects have been implemented and many hundred miles of AMD-polluted streams have been brought back to life. Formerly dead streams are now brimming with fish and other aquatic species. Local communities have the benefit of clean water.
The bulk of the funding for these restoration projects has come in the form of grants to State Abandoned Mine land programs from Surface Mining Control and Reclamation Act’s Abandoned Mined Land Fund and from EPA’s Clean Water Act Section 319 grant program. These funding sources are simply insufficient to address the vast scope of AMD problems (which are only a part of the overall need to address the health and safety and other environmental effects from abandoned coal mines). In addition, new revenue to the Abandoned Mined Land fund is currently scheduled to expire in 2021.
The rare earth and True Pigment processes can help address the funding shortage by providing an additional, independent source of funding for AMD remediation. They will be important tools in the decades to come as the battle continues to restore more than 7000 miles of streams polluted by AMD from abandoned coal mines continues in Pennsylvania, West Virginia, Ohio, Virginia, Maryland, Kentucky, Tennessee and Alabama.
Little Bear Run, Pennsylvania (Before and after Treatment)