Frequently Asked Questions
Q1. How does PLASCON® convert hazardous waste into environmentally acceptable discharges?
The waste is injected in to an extremely hot plasma stream that very rapidly breaks apart the molecular structure of the waste material. Individual atoms and ions are then transformed into simple molecules that are subsequently converted to inorganic compounds. These compounds are then discharged via conventional effluent treatment systems.
Q2. Why is the PLASCON® process different to incineration?
PLASCON® doesn't use a fuel such as natural gas, hydrogen etc. and there is no flame. The energy to complete the conversion of waste is provided by a direct current plasma-arc that heats a plasma gas to temperatures in excess of 10,000°C (incinerators typically operate at peak temperatures of 1,200 - 1,300°C). When the waste is mixed with the hot plasma gas it is heated extremely rapidly until the molecules break apart. No oxygen is required to complete this "destruction" process. The conversion (destruction) of waste in this way is referred to as pyrolysis.
Q3. What type of waste can PLASCON® destroy?
Virtually any organic liquid or gaseous waste can be destroyed in PLASCON® . In practice very fine slurries can also be fed to the process. In addition, the PCB contained in "solid" wastes such as PCB contaminated electrical transformers can be destroyed by firstly separating the PCB liquid from the solid material. Techniques such as solvent extraction, autoclaving and thermal desorption are all applicable pre-treatment processes.
If in doubt please ask and we will make an assessment of your specific waste stream.
Q4. What process inputs does the PLASCON® process require?
High purity (ideally 99.999%) argon is required as the plasma gas, approximately 250 kVA 3 phase electrical supply, bulk liquid caustic (NaOH), raw water and steam or oxygen depending on the waste material.
Q5. How large is a PLASCON® plant?
The main PLASCON® unit is skid mounted and is designed to be transported in a standard 20ft shipping container. The PLASCON® transformer/rectifier is installed separately.
Q6. Are there any special site requirements that need to be considered?
PLASCON® can operate in a very simple factory style building with a suitable bund around the PLASCON® skid. The building should have good ventilation. There are no special requirements other than adequate space adjacent to the building for the services such as: bulk liquid argon cylinder, oxygen cylinder (if required), caustic tank, cooling tower and any tanks required for effluent handling.
Q7. Are any special skills required to operate a PLASCON® plant?
The PLASCON® ; process can be likened to a small chemical processing plant. Plant operators should have plant experience preferably in a chemical process plant environment. However, the process is quite simple to operate and even untrained operators can quickly adapt to the process. It is advantageous to have access to qualified engineering input for non-routine situations.
Q8. What level of plant on-line time can I expect from the PLASCON® plant?
PLASCON® is a continuous process. Operational experience with the plant operating 3 shifts per day 7 days per week will typically yield an on-line fraction between 80% and 90%.
Q9. How safe is PLASCON® ?
The process control system monitors all critical process parameters and will, in the event of an adverse system trend that breaches pre-defined parameters, instantaneously shut down the plant. Because the volume of undestroyed waste contained within the process at any instant is in the order of milligrams, very little waste can escape to the environment. Despite the fact that the plasma temperatures are in the order of 10,000°C and higher, operators are not exposed to extreme temperatures or hazardous operating conditions.
Q10. Is PLASCON® a commercially proven technology?
Yes! The first installation was completed in 1992. This plant is still in continuous 3 shift/day, 7 day/week service. Nine other PLASCON® plants are currently in commercial use in Australia, Japan, Mexico and the USA. All have had their operation approved by their respective national EPA.
Q11. Is PLASCON® cost effective?
As the configuration of the PLASCON® process varies depending upon the waste, site, regulatory requirements etc. it is not possible to provide a meaningful price for the PLASCON®. However, PLASCON® is a small compact device and the capital cost is very competitive when compared to most other high performance destruction technologies.
SRL Plasma would be pleased to quote on your specific application following receipt of the preliminary information as detailed in the commercial overview. In Australia PLASCON® has proven to be more cost effective than other technologies including chemical and thermo-chemical processes.
The plant will destroy between one and three tonnes of waste per day depending on the chemical composition of the feed. It is important to note that the destruction cost is to a significant extent independent of the concentration of the toxic component within the feed. Therefore, the process is most cost effective when the waste is concentrated. In such cases the overall cost of destruction (including capital and running costs) will be competitive with incineration, particularly for heavily halogenated waste.
As PLASCON® is able, due to its small physical size, to be located adjacent to the source, or collection point, of the waste, significant cost savings in transportation of hazardous waste can be achieved when a PLASCON® system is implemented. In some existing instances tranportation of the hazardous waste accounts for over half of the current destruction costs using centralised incineration systems."
Q12. How long does the plasma torch last?
The plasma torch developed by CSIRO and SRL Plasma is particularly robust. It is a high efficiency torch that has been in commercial use, albeit with minor modifications and improvements, since 1992. The body of the torch will survive the most arduous conditions for several thousand hours of continuous use. Components directly exposed at elevated temperatures to the gasses resulting from the pyrolysis of the waste may require more frequent replacement, depending on the specific waste being treated, however, these components have been designed for quick change over and can be readily refurbished for later re-use.
Q13. Can PLASCON® be used to treat solid waste?
PLASCON® is directly suitable for the treatment of gases and liquids. Very fine particles can also be treated when suspended within a liquid. In cases where solids such as soil or electrical components are contaminated, it is necessary to first extract the contaminants. SRL Plasma has experience in using processes such as thermal desorption and solvent extraction in order to remove the contaminants from the solids. The resulting liquids can then be subsequently treated in the PLASCON® unit. Wastes which are solid at ambient temperature have also been disposed of through PLASCON® units by dissolution, slurrying, or melting the waste."