Pyrolysis process
• Pyrolysis is the chemical decomposition of organic materials by heating in the absence of
oxygen or any other reagents, except possibly steam.
• Pyrolysis can be used to reprocess the tyres into fuel oil, fuel gas, solid residue (steel wire)
and carbon black.
• The waste tyres are mainly composed of long chain of C-H molecules.
• Under normal process conditions the heat transfer will be done by radiation.
• The technology of pyrolysis, cracking, and monomerisation of used tyres is always a hot topic.
Tyre pyrolysis
End-of-life tyres contain a lot of chemical bound energy.
As a result of pyrolysis of waste tyres one obtains: high-energy gas, Pyrolysis oils, carbon black
and steel wire. The ratios of the first three products depend on process conditions, mainly on
temperature.
• The pyrolysis method for recycling used tyres is a technique, which heats whole or shredded
tyres in a reactor vessel containing an oxygen free atmosphere and a heat source.
• In the reactor the rubber is softened after which the rubber polymers continuously
breakdown into smaller molecules.
• These smaller molecules eventually vaporize and exit from the reactor.
• These vapors can be burned directly to produce power or condensed into an oily type
liquid, generally used as a fuel.
• Some molecules are too small to condense. They remain as a gas, which can be burned as fuel.
• The minerals that were part of the tyre, about 40 to 45 % by weight, are removed as a solid.
• When performed well a tyre pyrolysis process is a very clean operation and has nearly no
emissions or waste.
• The properties of the gas, liquid and solid output are determined by the type of feedstock
used and the process conditions.
• For instance, whole tyres contain fibers and steel. Shredded tyres have most of the steel and
sometimes most of the fiber removed.
• Batch wise Process is done by tyre pyrolysis.
• The steel can be removed from the solid stream with magnets for recycling. The remaining
solid material often referred to as "charcoal".
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Variety of polymer waste material is suitable as a raw material.
Given below is the list of suitable raw materials for pyrolysis:
Waste tyres
Rubber or rubber parts from vehicles
Electronic scrap
Mixed (HDPE, LDPE, PE, PP, Nylon, Teflon, PS,ABS,FRP etc)
Multi layered
Plastic disposable bottle
• The choice of feedstock and process (mainly operating temperature) can affect the value of
the finished products.
Input-output ratio of waste tyre
Type of Material Total Quantity Finish quantity
Nylon scrap tyres 1000 kgs
-550 to 600 liter of Pyrolysis oil
-50 to 80 kg of Hydrocarbon Gas
-300 to 350 kg of Carbon Black
Radial scrap tyres 1000 kgs
-400 to 450 of Pyrolysis oil
-50 to 80 kg of Hydrocarbon Gas
-300 to 350 kg of Carbon Black
-150 to 200 kgs of Mild steel tyre scrap
Yield of pyrolysis process:
H Pyrolysis oil (Fuel oil - 40 to 45%)
• The essential product of tyre pyrolysis process is pyrolysis oil referred as fuel oil (40 to
45 % of total quantity feed) which is used as a fuel component for heating in fire chamber.
Pyrolysis oil has flash Point between 60 to 93.3 °C.
• Purest quality of pyrolysis oil comparable to industrial diesel: selling price comparable to
industrial diesel LDO( light diesel oil)
H Carbon Black(30 to 35%)
• The vital product of pyrolysis plant is carbon black referred as "charcoal"(30 to 35% of
total quantity feed).carbon black has Industrial and commercial use.
H Steel wire(15 to 20%)
• For instance, whole tyres contain fibers and steel. Shredded tyres have most of the steel and
sometimes most of the fiber removed.
• The steel wire(15 to 20%) can be removed from the carbon black with magnets for recycling
after pyrolysis process & sold to the steel dealer
H Hydrocarbon Gas(5 to 8%)
• The smaller molecules eventually vaporize and exit from the reactor. These vapors can be
burned directly to produce power or condensed into an oily type liquid, generally used as
a fuel. Some molecules are too small to condense. They remain as a gas (5 to 8% of total
quantity feed) which can be burned as fuel.
H Advantages of pyrolysis plants
• Purest quality of pyrolysis oil as finished product.
• Use of green technology to achieve environment friendly processes.
• Automatic safely valve (pressure and temperature valve) use to improve safely,
profitability & ease of operation.
• Industry is energy self-sufficient.
• No external fuel required for heating.
H Benefits of pyrolysis plant
• Recover energy and value from waste in form of fuel, steel wire and charcoal.
• Reduce tyre land pollution.
• Eco-friendly recycling of tyre.
• Commercially viable process.
• Product is used as substitute to LDO/furnace oil.
• Perfect solution for polymer waste management.
• Raw material available.
21 окт 2024
