Hot Plasma System

Thermal plasma technology applications

Hot plasma is a state of matter where a gas is heated to extremely high temperatures, causing it to ionize and become electrically charged. Plasma is often described as the fourth state of matter, alongside solids, liquids, and gases.

In a hot plasma, the electrons are stripped from the atoms and molecules, creating a cloud of positively charged ions and negatively charged electrons that interact with each other through electric and magnetic fields. Hot plasmas can be found in a variety of natural and artificial environments, including the sun, stars, lightning, flames, and certain types of industrial processes.

Hot plasmas have many unique properties, such as the ability to conduct electricity and generate magnetic fields, which make them useful for a wide range of applications in fields such as energy, materials processing, and space exploration. For example, plasma physics is used in the design of fusion reactors, which aim to generate energy by recreating the conditions of the sun on Earth.

The current global ecosystem of natural materials, energy and ecology requires the development of novel metallurgical technologies and equipment based on the use of thermal plasma as a concentrated heat source and for chemically active components of processes.

Thermal plasma in metallurgy is now evolving in two directions: improving traditional metallurgical technologies and developing mostly new plasma metallurgical technologies. Plasma technologies are typically categorized as smelting and reducing (extracting) processes, based on the breadth of their use.

These methods are distinguished by the fact that the materials are finely powdered and, in most cases, subjected to partial reduction prior to processing. The goal of all of the different plasma units is to provide a quick melting time for the raw material and a good contact (maximum area) between the reducing gas and the melted oxide material using diverse technologies. Plasma reduction technologies are characterized in general based on the kind of heat exchange between the plasma arc and the treated material, as well as the parameters under which the reduction processes are carried out.

Hot plasma has application in metallurgy, hazardous waste elimination, coating methods such as
plasma spraying or chemical vapor deposition (CVD), the production of fine/nano powders, and energy generation. For the past decade, hot plasma technology has also aided in the recovery of value-added metals from slag or ore. However, the mining sector requires more cost-effective and efficient ore and slag concentration technologies, as well as precious metals processing
technology. Consider that gold ore, slag, or other materials have a break-even point (BEP) of at least 0.2 ounces of gold per ton.

Plasma gasification is another method that uses plasma to transform organic materials into synthetic gas and slag. An electric arc plasma torch ionizes the gas and transforms organic material to a synthetic gas, leaving a solid waste. The power is then generated using synthetic gas. Plasma gasification is a cost-effective method of generating electricity from municipal trash or
biomass. Plasma plants, on the other hand, are considered costly and limited in capacity.

Avimetal has developed a cost effective, compact-sized RF Plasma Gasification System with outputs ranging from 120 to 360 kW module that can be installed in parallel to improve capacity
by combining several feeds and torches into a single system. It’s a turnkey modular system that’s easy to set up. Plasma furnaces, similar to plasma-arc furnaces, function in an ‘open bath’ to
produce metals and alloys from natural and waste raw materials in industrial manufacturing. Industrial furnaces, in which the powdered material is injected around the heating surface
of the resultant plasma cone, spin at a velocity of 50-1500 min around the furnace vertical axis at a 5-15° angle and with an arc length of 500-750 mm, are well known. According to the most recent statistics acquired from processing powder slimes and slags in a 1 mw plasma furnace, specific energy consumption is 1300 kWh/t powder, and reducing agent consumption is 90-300 kg depending on the kind of treated material.