|
Process Details |
|
The Plastic-to-Diesel (P2D) process utilizes EZ-Oil Generator to reliably produce transportation-grade (road use), low-sulphur diesel from mixed waste plastics. The P2D process addresses all the traditional problems associated with pyrolysis technology. The process employs patented highly-energetic far infra-red (FIR) heating rods that promote efficient cracking and minimise coking problems. Far infra-red radiation is highly energetic and close to the microwave region of the electromagnetic spectrum.
The production of gasoline, kerosene and diesel from waste plastics is an emerging technological solution to the vast amount of plastics that cannot be economically recovered by conventional mechanical recycling operations. This involves the use of pyrolysis which permits recovery of valuable gasoline and diesel-range hydrocarbons from waste plastics that are otherwise landfilled.
Pyrolysis recycling of mixed waste plastics into generator and transportation fuels is now seen by many as the answer for deriving value from unwashed, commingled plastics as well as managing their desired diversion from landfill.
The viability of pyrolysis is assured by the lack of other recovery options for such waste plastics besides landfilling and incineration. Factors such as the increasing pressure on companies to adopt sustainable outlets for their end-of-life plastics; the introduction of extended producer responsibility and product stewardship directives; together with the implementation of legislative measures to deal with waste plastics, are significant drivers that will further increase the adoption of the pyrolysis route for waste plastics.
The P2D plant has the following attributes: o steady-state continuous operation o continuous removal of heavies/residues o high degree automation o energy savings by use of focussed far infra-red heating o no expensive catalysts or consumable reagents o integrated distillation, fractionation, refining and stabilization steps o no hydrocarbon emissions/ no flare o the diesel fuel product will be ultra-low in sulphur (<< 50 ppm)
The future of waste plastics
The P2D project could ultimately recycle all post consumer plastics from Supermarkets and retail stores that are not currently recycled (this includes shopping bags, lightweight plastic overwrap, thin thermoform trays, etc). This paves the way for eventual collection of waste plastics packaging through supermarket drop-offs as a collection infrastructure for 'take back' schemes.
If the P2D project has the potential for diverting vast quantities of plastic waste from landfill and also capturing the embodied energy content of the plastic.
|
P-Fuel Plastics to Diesel (P2D) |
|
P-Fuel products |
|
Plant in Detail
|
|
Pyrolysis Reactor
There are other plants that have been developed to convert plastic and waste oils into diesel and other fuels but many of these use external heating sources for the reactor to melt the plastic to enable pyrolysis to take place. Outer heating is inefficient (due to radiant heat losses and due to the low thermal conductivity of plastics) and are not capable of precise and uniform heat and temperature control.
The heating system in the pyrolysis reactor uses multiple far infra-red heating rods to give precise and efficient heating of the mass of molten plastic. Inner heating is the opposite of the more conventional external heating where the pyrolysis chamber is externally heating either directly by gas flame or indirectly by hot air. The novelty of the design lies in the Far Infra-red internal heating rods which are not prone to 'coking' problems.
Far Infra-red (FIR) is that region of the electromagnetic spectrum lying between the middle infra-red and microwaves. This covers the wavelength range approximately from 15 m to 1 mm and thus is electromagnetic radiation with wave frequencies longer than that of thermal infra-red (between 25 and 1000 micrometers). The heating rods use ceramic far infra-red heaters, which have a 96% radiant efficiency, built into stainless sleeves.
Far Infra-red internal heating rods used in the plant show no coking after many thousands of hours of operation. Coking is one of the main technical barriers to the pyrolysis of plastic wastes using conventional external heating for the reactor. |
|
"The novelty of the design lies in the far infra-red internal heating rods which are not prone to 'coking' problems" |
|
Technologically Advanced
The development of commercially viable plastic pyrolysis processes has up to now been hindered by the need to engineer around various process problems such as reactor fouling by carbon deposits, poor heat transfer of molten plastics, the requirement for integrated fractionation of products, separation of water and suspended carbon from the liquid fuels and integrated desulphurization.
Problems with many pre-existing plastic cracking technologies include: • non-continuous (batch) processes (not commercially viable); • coking and carbon deposits on heat exchanging surfaces; • stickiness of sand particles in fluidized-bed processes; • unsatisfactory fuel quality; • relatively high sulphur levels (100–700 ppm) in end product.
The plastic-to-diesel process has been specifically engineered to overcome these limitations. The P-Fuel has solved all FIVE problems with this technology to date: • continuous operation: (both the input and solid residue removal are continuous). • no coking: (the plant uses a novel heating process to minimize coking). • full fractionation and distillation: (diesel meets performance standards). • desulphurization: (< 50 ppm residual sulphur). • minimised emissions: (joint development with Co-Generation vendor to to eliminate problematic emissions).
Process Attributes
The main features of the EZ-Oil Generator™ are: • Easy Installation: This facility is assembled on several movable base platforms whose size is about 6000mmx2100mm (19.7 feet x 6.9 feet). In most cases no civil engineering is needed for installation. • Flexible operation: It can be operated continuously or in batch runs. The feeding of plastics and discharging of char (solid residue) can be done while the unit is in operation. • Stable Operation: There is minimal or no coking in the reactor, and it can operate for extended periods. • No Secondary pollution: In general, there are three by-products in the plastic decomposing unit, char and generator flue gasses. • Plant is highly automated with Siemens Master Automation and an Austrian-built shredder drum/extruder/venting/melt filtration pre-processing unit. The plant can be run on a 7 day per week rotating shift basis. • Economical Operation: Cost of operation is far less than other conventional systems currently available on the market. Utilizing the inner heating system powered by electricity, the average cost per tonne of waste plastic to convert to oil is about $20.00 USD using the average cost of $0.05 per kwh. Since there is <20% loss of heat efficiency, the savings are immediately realized as compared to other fuels or heating systems.
Diesel End Products
The P-Fuel process can produce either industrial-use diesel oil (also known as 'agricultural diesel') or refined transportation-grade diesel (road use diesel which conforms to the European diesel fuel standard EN590).
The P-Fuel process which produces automotive grade diesel produces diesel that meets the road fuel standards. This is a specific cut of hydrocarbons with a specific property profile. Not all the liquid fuel that is formed from the pyrolysis of plastics is auto diesel. There is also heavy oil, light oil, gasoline (octane) and char (solid carbonaceous residue). Only by distillation and fractionation of the liquid fuel can specification diesel been produced. Extensive development work has found that actual auto diesel yields of 50-60 wt% are the highest that can be achieved with any technology.
The P-Fuel process is designed to produce automotive grade diesel or transportation-grade diesel, from a range of feedstock compositions. In addition to boiling point curves, cetane rating, flash point and viscosity there are low temperature properties such as pour point, cloud point, CFPP that must be in specification.
The difference between the plant designs is the cheaper plant which produces mixed diesel oil only, does not include the following:
a. the second fractionation/distillation tower b. the desulphurization system c. the additive dosing system and additive storage tanks (the additives are cloud point depressants and pour point modifiers)
hence, the lower capital cost of the Mixed oil plant.
By-products
All the LPG and gasoline produced by the process is fed into a state-of-the-art generator for power generation and hence no hydrocarbon emissions. The entire process is electrical heated (hence no flame heating, gas burners, etc.) and the shredder drum/extruder is a large European extruder with a heavy-duty drive and multiple resistance band heaters. |
|
P-Fuel Plant Options and Pricing
The pricing depends on the capacity of the plant, the type of output product and the number of plants ordered. Three different capacity plants are available, 4,500 T/Y, 12,500 T/Y or 25,000 T/Y. Output is based on plant uptime of 7000 hr/yr (minimum) since preventative maintenance and predictive maintenance are factored in.
The plants are designed to produce either Industrial-use diesel oil (also known as 'agricultural diesel') or refined transportation-grade diesel (road use diesel which conforms to the European diesel fuel standard EN590). Pricing is available on request.
Operational Plants
has commercially operating plants in both North and South Korea that produce Mixed oil (Burnable industry fuel) and not the Refined diesel oil (i.e. refined transportation diesel).
The Melbourne (Australia) plant currently under construction will be the first plant to produce refined transportation diesel.
|
