Proposal – Recovering the Value of Waste for
Environmental and Energy Sustainability
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Environmental Problem Statement
Two significant environmental issues lead us to explore the benefits of using waste as a source for energy. First, the United States produces 1.4 billion tons of waste materials per year, adversely affecting air and water quality, decreasing land values, limiting future use of land, and increasing costs to municipalities, industry, and the consumer. The challenge is to manage the waste and residues in a sustainable way.
Geographic areas experiencing rapid population growth and industrial productivity are particularly challenged. In addition, some sectors have unique waste management problems that the current waste infrastructure does not readily address. These and other waste-related problems, such as residues from meat packing and concentrated animal feeding operations, were identified in response to EPA’s Environmental Technology Council solicitation. Several waste-to-energy technologies, such as waste gasification, are being explored to address many of these problems. This Action Team will investigate the technical and economic feasibilities of and barriers to applying existing and emerging technologies.
The second challenge lies with the increasing demand for primary energy, leading to depletion of natural resources, degradation of ecosystems, and generation of significant amounts of solid waste, water pollution, and atmospheric pollution. These problems will continue to increase if new technologies are not pursued.
U.S. consumption of primary energy is increasing at an annual average rate of 2.4 percent. The production of energy products permanently consumes coal, natural gas, and petroleum resources. The Energy Information Agency predicts that the U.S. domestic supply of natural gas will be exhausted in 50 years; the coal supply will be spent in 250 years. Conservation of these resources is prudent to ensure future generations have a source of energy while alternative methods are being developed. Residue materials generated in the United States have the potential for supplying 97 quads of clean domestic renewable energy. (Note: 1 Quad = 1,015 British thermal units [BTUs].) The recovery of this untapped source of energy can contribute to sustainable energy production in the United States, while reducing the adverse effects on the environment.
These two trends present opportunities: gasification and other waste-to-energy technologies may be both waste management and alternative energy solutions.
The Resource Conservation and Recovery Act program is interested in promoting waste as a resource to be used for other purposes. Some industrial, hazardous, municipal, and agricultural wastes are suitable for generating chemical feedstocks or conversion to “clean” energy. For example, gasifiers can accept a variety of these wastes as fuel, and although many facilities worldwide currently use some of these wastes as supplemental fuels, this is not the case in the United States.
Gasification and other waste-to-energy technologies may also help address other challenges:
Definition of the Technology Challenge
Gasification technology can accept a variety of fuels and convert organic materials to hydrogen and carbon monoxide (a product called synthesis gas or “syngas”). Syngas can subsequently be used for production of a variety of fuels and chemicals and can play a key role in an evolving hydrogen economy. The carbon monoxide can be converted to carbon dioxide and sequestered in underground formations to reduce the production of greenhouse gases in the production of energy, possibly resulting in vast environmental and economic benefits. In addition, air pollutants such as mercury, sulfur oxide, and particulate matter are emitted at much lower levels compared to other technologies.
Gasification has successfully demonstrated the ability to convert a variety of residue materials, fossil fuel resources, and municipal, industrial, and hazardous waste materials into syngas. For example, the gasification of coal or petroleum coke can be supplemented with biomass or industrial process residues to produce clean energy and chemicals. The use of residue materials as a supplemental feedstock to coal or petroleum coke reduces the amount of residue ultimately managed as waste, while conserving national resources. In addition, gasification technologies are capable of reducing the production of wastes when producing energy and chemicals because gasifiers generate co-products and useful by-products. Elemental contaminants such as sulfur and chlorine are captured and sold as co-products; slagged gasification residues can be by-products used as a substitute for aggregate in road or concrete applications.
Milestones, Actions, and Due Dates
The mission of this Action Team is to develop and implement a plan that:
The team will investigate gasification applications first, focusing on the renewable use of a variety of wastes in the production of syngas and identifying ways to assist in the development of such applications. Other technologies will subsequently be investigated.