Plasma Gasification Turns Waste-to-Energy
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Waste-to-energy is the new holy grail for the energy industry, but it’s based on an age-old concept: burning trash for fuel. Just like wood and coal, garbage too can generate the heat needed to run turbines and generate electricity. Incinerating garbage is a commonplace practice in most countries, and the added benefit of generating energy while doing it only makes sense. The only problem is that burning trash emits various toxic chemicals that can pollute the air and lead to ozone degradation when applied on a massive scale. However, that’s all changing with new technologies promising cleaner waste-to-energy generation, and the coolest of these technologies has to be the Plasma Gasification Process (PGP).
PGP is the latest craze in incinerator technology, and for physics buffs, the prospect of using plasma—the “fourth state of matter”—is an intriguing prospect in itself. Essentially, the Plasma Gasification Process (also known as plasma arc gasification) works by creating an electrical arc between two electrodes spaced apart. Pressurized inert gas is passed through the arc and diverted to a sealed container of garbage. Temperatures inside the container can reach 25,000°F (13,900°C) within the arc column.
At such high temperatures, matter is literally broken down into its basic elemental forms in an inert gaseous state, and that synthetic gas—commonly called “syngas”—is harvested for uses similar to natural gas, such as running turbines in an electric power station, or uses similar to hydrogen gas, such as running fuel cells. Syngas can even be further refined into liquid fuels that can potentially run vehicles. Using the Plasma Gasification System, there is approximately a 99 percent conversion from solid-state waste to syngas. The remaining one percent of solid waste left behind by inorganic materials—termed “slag”—can be further refined, but at cost of course. For every 1,500 tons of waste, PGP can generate approximately 60-megawatts energy equivalent.
The syngas created by PGP can be reintroduced into the overall system as the energy supply that runs the plant, powering everything from the plasma torches to the conveyance system that feeds the waste. Thus, creating an energy efficient loop incinerator that effectively minimizes landfill and doesn’t release toxic gases. The process is even hailed for its ability to break down difficult to process and hazardous materials like batteries and medical waste.
According to the Georgia Institute of Technology, “Plasma gasification can create more renewable energy than the projected energy from solar, wind, landfill gas, and geothermal energies combined.”
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Now here’s the catch. While this plasma technology has been applied with varying success to small-scale and test facilities, companies are still racing to perfect the process to work well on a larger-scale that can be fully integrated with municipal waste-management operations for major cities.
Hitachi Metals Ltd. and Westinghouse Plasma developed one of the world’s first successful plasma gasification facilities in Yoshii, Japan in 2000. The plant processed 166-short-tons of waste per day, and the success led to the construction of two other plants. Japan’s Utishinai City plant has been successfully converting municipal waste to energy since 2001 and has served as a model for the onset of the plasma waste-to-energy era.
Plasma gasification company Alter NRG has since acquired Westinghouse Plasma and is currently planning upward of 50 PGP projects worldwide.
Plasco Energy Group is taking a different approach with its proprietary plasma gasification process that it claims can reduce net energy consumption in the system, thus making it even more efficient. Plasco’s process begins by removing any materials in the municipal waste that can be traditionally recycled. Then, the remaining waste is fed into a traditional gasifier (not plasma), which uses recovered heat from the overall system to gasify the waste. This releases various gases, including highly toxic gases that are then fed through a plasma arc for further refining. Plasco claims that using the plasma arc to refine crude gas rather than incinerate the solid waste itself is much more energy efficient.
Any remaining solid waste from the Plasco process is then fed into a plasma chamber that melts the waste into a liquid that, when cooled, is similar to glass and can be used in various construction applications. The Plasco gas refining process recovers various usable materials, from water to salt, sulphur to heavy metals, that can also be sold to market to further balance the overall cost of the system.
Plasco Energy Group, Alter NRG and other plasma gasification companies will lead the way in the waste-to-energy revolution. Converting garbage into energy may not be the sexiest of renewable energy options, but its practicality far exceeds that of even the most promising solar and wind developments to date, especially when you consider that solar and wind farms don’t do anything to reduce landfill.
Itronics successfully tests manganese recovery process
Itronics - a Nevada-based emerging cleantech materials growth company that manufacturers fertilisers and produces silver - has successfully tested two proprietary processes that recover manganese, with one process recovering manganese, potassium and zinc from paste produced by processing non-rechargeable alkaline batteries. The second recovers manganese via the company’s Rock Kleen Technology.
Manganese, one of the four most important industrial metals and widely used by the steel industry, has been designated by the US Federal Government as a "critical mineral." It is a major component of non-rechargeable alkaline batteries, one of the largest battery categories sold globally.
The use of manganese in EV batteries is increasing as EV battery technology is shifting to use of more nickel and manganese in battery formulations. But according to the US Department of Interior, there is no mine production of manganese in the United States. As such, Itronics is using its Rock Kleen Technology to test metal recoverability from mine tailings obtained from a former silver mine in western Nevada that has a high manganese content.
In a statement, Itronics says that its Rock Kleen process recovers silver, manganese, zinc, copper, lead and nickel. The company says that it has calculated – based on laboratory test results – that if a Rock Kleen tailings process is put into commercial production, the former mine site would become the only primary manganese producer in the United States.
Itronics adds that it has also tested non-rechargeable alkaline battery paste recovered by a large domestic battery recycling company to determine if it could use one of its hydrometallurgical processes to solubilize the manganese, potassium, and zinc contained in the paste. This testing was successful, and Itronics was able to produce material useable in two of its fertilisers, it says.
"We believe that the chemistry of the two recovery processes would lend itself to electrochemical recovery of the manganese, zinc, and other metals. At this time electrochemical recovery has been tested for zinc and copper,” says Dr John Whitney, Itronics president.
“Itronics has been reviewing procedures for electrochemical recovery of manganese and plans to move this technology forward when it is appropriate to do so and has acquired electro-winning equipment needed to do that.
"Because of the two described proprietary technologies, Itronics is positioned to become a domestic manganese producer on a large scale to satisfy domestic demand. The actual manganese products have not yet been defined, except for use in the Company's GOLD'n GRO Multi-Nutrient Fertilisers. However, the Company believes that it will be able to produce chemical manganese products as well as electrochemical products," he adds.
Itronics’ research and development plant is located in Reno, about 40 miles west of the Tesla giga-factory. Its planned cleantech materials campus, which will be located approximately 40 miles south of the Tesla factory, would be the location where the manganese products would be produced.
Panasonic is operating one of the world's largest EV battery factories at the Tesla location. However, Tesla and other companies have announced that EV battery technology is shifting to use of nickel-manganese batteries. Itronics is positioned and located to become a Nevada-0based supplier of manganese products for battery manufacturing as its manganese recovery technologies are advanced, the company states.
A long-term objective for Itronics is to become a leading producer of high purity metals, including the U.S. critical metals manganese and tin, using the Company's breakthrough hydrometallurgy, pyrometallurgy, and electrochemical technologies. ‘Additionally, Itronics is strategically positioned with its portfolio of "Zero Waste Energy Saving Technologies" to help solve the recently declared emergency need for domestic production of Critical Minerals from materials located at mine sites,’ the statement continues.
The Company's growth forecast centers upon its 10-year business plan designed to integrate its Zero Waste Energy Saving Technologies and to grow annual sales from $2 million in 2019, to $113 million in 2025.