Greentech Media

Innovations in recycling and waste technology address pollution problems that directly affect our living environment. By focusing on the quantity and composition of waste going into the ground, new waste-disposal processes will help us regenerate soil and reduce the amount of land needed for disposal. Recycling and waste technologies, along with water, form the baseline for green technology. These innovations are both necessary and available. Improving waste-disposal and recycling processes are neither expensive nor highly technical. They have the potential to influence the quality of life for individuals across the globe.

The market potential for these technologies is huge. Ground contamination is a serious problem in a number of locations, especially in countries where the majority of individuals depend on agriculture to make a living. If China or India were to adopt widespread waste-disposal or recycling regulations, the companies producing the most efficient and effective technologies would have a ready-made market.

Key Components

• Bioremediation - These processes use microorganisms, fungi and enzymatic reactions to decontaminate soil. Bioremediation, which has both aerobic and anaerobic functions, uses the enzymatic pathways and catabolic reactions of microorganisms to break down soil contaminants or convert them into nonhazardous or nontoxic compounds. A well-known extension of this process is the use of hydrocarbanoclastic bacteria (HBC) to degrade petroleum in marine environments for waste cleanup. Microbiologists and genetic engineers are researching new micro-organic processes that will allow bacteria to break down a larger array of soil contaminants without needing to remove soil or alter the environment.
• Phytoremediation - Phytoremediation is used to extract and break down heavy metals, including uranium, lead, cadmium and arsenic. Plants in contaminated areas absorb chemicals through their root structure, transporting them to the leaves and stems. Plants will continue to absorb contaminants until their tops are harvested. This process requires numerous plant lifecycles to successfully clean contaminated sites. Current research on plant genetics is focused on building 'hyperaccumulators,' plants that grow faster and absorb more contaminants than those plants traditionally used in phytoremediation (sugar beets, sunflowers, poplar trees and ragweed).
• Waste-to-Energy - Waste-to-energy conversion is similar to the biomass-gasification and IGCC processes, except that the feedstock is trash and not biomass or coal. Instead of incinerating garbage, waste-to-energy plants use decomposing matter from landfills or fresh carbonaceous matter and convert it to liquid fuels using thermal and fermentation technologies. The biodiesel movement is a grassroots extension of waste-to-energy technology.
• Plasma-Arc Gasification - Plasma-arc gasification is a new technology that melts and gasifies solid waste at extremely high temperatures. The plasma arc stretches across two electrodes, which vaporizes garbage as it falls through the closed-loop plasma converter. The two byproducts of plasma-arc gasification are gasified waste and solid rubble. The gasified waste is syngas, which can be used to fire a turbine generator. A plant planned for Port St. Lucie, Fla., will use the rubble byproduct to pave roads in the community. There are currently a handful of operating plants in Japan, and two plants in the works for Florida.

Plasma-Arc Gasification
Geoplasma LLC	StarTech	PlascoEnergy Group

• Mechanical Biological Treatment (MBT) - MBT plants combine waste processing with anaerobic waste digestion, which allows for lower rates of overall waste disposal and conversion of waste into methane-rich biogas. Instead of having separate facilities for recycling, commercial and industrial waste and household waste, MBT plants aggregate all types of garbage into a single plant, and dispose of only what cannot be converted into fuel for energy. All waste that can be converted is sent into an anaerobic-digestion facility on site. Anaerobic-digestion processes subject waste to bacterial hydrolysis to begin the breakdown process. Acidogenic bacteria, which breaks down waste into hydrogen, ammonia and carbon dioxide, is then added into the mix. Finally the waste material is converted into methane using methanogenic bacteria. Anaerobic digestion requires high construction costs and produces biogas with low efficiency. Further research on anaerobic-breakdown technology, including the addition of temperate and pressure monitors to maintain a constant environment, is required to bring costs down while increasing the conversion efficiency required for wide scale commercial adoption.
• Molten Closed-Loop Gasification - Though most waste-to-energy gasification processes can be described as closed-loop, a promising new technology takes this a step further by making garbage disappear within the system. By melting construction and household waste into a bath of molten iron, molten closed-loop gasification produces only syngas and slag. Like nearly all waste-to-energy technologies, this process aims to reduce the use of landfills.

Molten Closed-Loop Gasification

Ze-gen

• Technology Recycling - The European Union, Canada, most American states and many countries in Asia have banned the disposal of electronic waste in landfills. Most electronic devices contain both high-value components (gold, platinum, copper) and toxic chemicals (mercury, lead, PCBs). One study estimates that electronic waste accounts for 70 percent of all toxic waste in the U.S. While many countries require device manufacturers to handle up to 75 percent of electronic waste disposal, common disposal practice involves shipping electronic waste to developing countries with light regulations on waste disposal and environmental health. Electronic-waste processing is a complicated process, requiring disassembly, materials sorting and recovery and safe disposal. As more countries continue to legislate against direct disposal, investment for streamlining and simplifying electronic-waste disposal will increase.

Technology Recycling
eWaste	TechTurn