5-7 OCTOBERISFR2011

25

TOLEDO (SPAIN)EVALUATION AND USE OF THE FRACTIONS FROM CRACKING OF WASTE
PLASTICS ON PRODUCTION UNIT
Jozef Mikulec1, Ľubomír Švantner2, Ivan Vailing3
1VÚRUP, a.s. Bratislava, Slovak Republic,
2Castor & Pollux, Bratislava, Slovak Republic,
3Ivan Vailing, Rasol Consulting, Ltd., Slovak Republic

e-mail:jozef.mikulec@vurup.sk

Abstract
Described technology operated by Castor & Pollux enables the processing of separated plastic waste to liquid fuel, which
can be used plastics mechanically contaminated with water content, with of different colors and forms and without removing
the printed matter which recycling by re- granulation is very difficult and costly. Presented results showed that the catalytic
cracking of plastic waste can be used as components of motor fuels as feedstock for pyrolysis, respectively. heat andelectricity cogeneration units.

Keywords: waste plastics, thermal cracking, catalytic cracking, gasoline fraction, diesel fraction, co-generation.

1. Introduction
Raw materials (chemical, tertiary) recycling of plastic waste
use technological processes in which chemical reactions
take place. At higher temperatures macromolecules cracks
to monomers, which can be reused for the synthesis ofpolymers and liquid hydrocarbons which are by nature
close to petroleum fractions. They are used in the chemicalindustry. Two major chemical recycling processes arethermal and catalytic degradation. For thermal degradation,a large range of products and requires high operating
temperatures from 500°C to 900°C. On the other hand,
catalytic degradation may provide a solution to theseproblems, controlled distribution of products and reducing
the reaction temperature.

2. Materials and Methods
Technology PCP 700 is based on cracking of separated
waste plastics based on polyolefins (PE and PP) in thepresence of a catalyst at a temperature of 390 to 420 ° C.
The process of liquefaction of waste plastics in the reactor
being heated with natural gas and gas produced during thecracking. Heat transfer between flue gas and bottom of thereactor as a heat transfer medium was used for liquid metalor other inorganic melt. Plastic waste is melted in thereactor and subsequently cracked (originally long molecules
are broken down into shorter, respectively.), to give theproduct in the gas phase, which is in tubular heatexchangers cooled and fractionated in two stages. The
degree of conversion or degradation efficiency depends on
the operating temperature, with increasing temperature
increases the depth of transformation chains and increasing
the share of gas units. The described technology consists of
two devices PCP 700th Any technological line PCP 700 iscomprised of 2 reactors with furnace, two stage cooling andfractionation, with a hydraulic unit for compression -interiores libro.indd 25

compaction and displacement of material input into thereactor, pipe systems with pumps for transportation ofhydrocarbon mixtures into the tank and the gas mixture to
the burner, lens stack and control panel. Tanks products,
post-combustion flue, waste storage input and somesmaller facilities are common to both devices PCP 700.
After cracking and condensation of liquid hydrocarbons
gaseous product are burned in special burners. Gas yield
is about 12 to 18% by weight. Gaseous products includehydrocarbons C1 to C5., their composition depend on thecomposition of the starting material and reaction
temperature.
Wide fraction is the product of decomposition of plastics inthe first reactor. Depends on the composition of the starting
material and process control (temperature). The attachedtable shows selected parameters of the test operation of theplant. The product is light brown, at normal temperature issolid, when heated, has the appearance of clear liquids. It
can also be used as heating oil, but in the process is used
as a feed into the second reactor in which cracking takes
place to light fraction.
Tab. 1 Properties of wide fraction form PCP 700
Parameter
Sulphur
Density at 15 °C
Ash
Iodine number
Kinematic viscosity 40
Carbon residueCetane number
Heat capacity
NitrogenTotal acid number
CFPP
Lubricity (wsd 1,4)

Test
EN ISOEN ISOEN ISOEN 14111
EN ISO
65 6210EN ISOSTN 65
ASTM DSTN 65
EN 116
ISOUnitmg/kg
kg/m3% wt.
g J2/100
mm2/s
% wt.
kJ/kg
mg/kg
mg
°C
micromValu
20822,
0,00
68
3,13
0,06
54,4
44502
7,79
40405

Precision
2,5 %
0,1 %
20 %
2%
1,5 %
20 %
1,0 %

2%
3°C
10 %

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6th International Symposium on Feedstock Recycling of Polymeric Materials

Naphtha fraction form cracking of plastic is a light yellow
clear liquid, which contains about 6.9% by weight.
monoaromatics and the rest is a mixture of n-alkanes andalkenes, in particular 1-olefins. This corresponds to a highnumber and value of bromine number and aniline point.
Sulphur content is low. For comparison of FCC gasoline
fraction contains an average of 25.3% wt. aromatics, 0.88wt%. benzene, 24.6 mg / kg of sulfur, 32, 89 wt% olefins.
The difference is in the structure of olefins.
Middle fraction (CPoil MF) is a mixture of liquidhydrocarbons in the range of bp 150-360oC. It is a paleyellow liquid with a characteristic odor. The averagecomposition is in Table 2. Middle fraction can be used topower diesel engines for cogeneration heat and electricity.
The advantage is the low content of polyaromatichydrocarbons. The sulfur content depends on the impurities
that are present in the raw material. For use in diesel
engines is necessary to add lubrication additives. Given thecontent of unsaturated hydrocarbons oxidation stability issurprising. Middle fraction can also be used as acomponent in diesel fuel as a potential for steam cracking
for olefin production.
Table 2 Properties of middle fraction
Properties

TestUnit
methodDensity at 15 °C
EN ISO 12
kg/m3
185
Cetanenumber, EN ISO
min.
5165
EN ISODistillation% (V/V) recovered 3405
at 250 °C,% (V/V).
% (V/V) recovered at% (V/V).
350 °C,,°C
95%(V/V)
recovered at
Viscosity at 40 °C
EN ISO
mm2/s
3104
PCA
EN 12916 %(m/m).
Sulphur, max.
EN ISO %
20846
mg/kg
Total contamination EN 12662
mg/kg
max.
Oxidation stability, EN ISO
g/m3max.
12205
MTF (CFPP), max.
EN 116°C- class B

Requirement Middle
EN 590
fraction
820 – 845

797

51

43,765
85
360

35,1
97,3
336

2,0-4,52,518

110,510

1,2-2024

1,8250,710+73. Results and discussion
Middle fraction was tested on engines:
Volvo TAD 1643GE / V ACT injection
Volvo TAD 532 GE / V ACT injection
Deutz F8M1015CP / common rail Cummins KTA19G8 / common rail.
Best value of the ratio of output / consumption enginesachieve fuel at 63 ° C. The tested engines were set on
diesel fuel for use on medium fraction must be reset. In
original setting the fuel consumption is higher by about 6%.
Liquid product from polyolefin cracking were tested bypyrolysis GC applying addition of depolymerisates to theraw material distilled up to 300°C; distillation residue wasalso obtained. Similar procedure was used without the
depolymerisates added.

interiores libro.indd 26

Ethylene yields are higher in pyrolysis with 5% wt. additionof LDPE depolymerisate below 300°C than with residual
undistilled LDFE depolymerisate at all temperatures (800,820, 840°C). Propylene yields are approximately the samewith both depolymerisate types from all raw material types.
Clearly much higher yields of benzene (almost 100%increase, 800°C) than with pyrolysis of pure heavy gasoline
were achieved by the addition of 5 weight % of residual
non-distilled HDPE depolymerisate.
On the basis of the achieved results, it can be stated that up
to 5 weight % of the raw material for heavy gasoline
pyrolysis can be replaced by residual non-distilled PP andHDPE depolymerisates, while the yields of basic pyrolysis
constituents (such as ethylene, propylene and ethane) areapproximately the same. However, even the substitution of
5 weight % of the heavy gasoline raw material by HDPE,
LDPE and PP depolymerisates in distillation scale below
300°C is more than successful.
The chance to use depolymerisates from polyolefins as apart of the raw material for FCC was checked by help of
MAT (microactivity test). Depolymerisates should notcontain organic constituents such as nitrogen, sulphur,metals which are catalytic poisons for the FCC catalyst.
Joining the waste plastics cracking process with refinerytechnologies such as FCC is a feasible solution for theprocessing of waste plastic materials with economic goal.
Compared to combustion in power stations, the use ofwaste plastics in refinery will result in a visible economicaleffect. The use of depolymerisate from LDFE and HDPE
appears to be optimal for practical application in the FCC
process. In most samples, the addition of depolymerisates
to standard FCC raw material increased the fraction yield
which increases with rising temperature, and decreased theproduction of LCO, MCB and coke; this is rather desirable
in the production of gasoline.

4. Conclusion
Products of cracking of waste plastics can be used toproduce energy, as a component of motor fuels as well as
the feed for the pyrolysis. But require treatment withadditives or can be used as fuel components. The
advantage of the processing of polluted waste plastics.

References[1] Lee K., Noh N., Shin D., Seo Y. Comparison of plastic
types for catalytic degradation of waste plastics into liquid
product with spent FCC catalyst, Polymer degradation andStability 78, 539-544, 2002.
[2] Ding W., Liang J., Anderson L. Thermal and catalytic
degradation of HDPE and commingled post-consumer
plastic waste, Fuell Processing Technology 51, 47-62, 1997.
[3] Ucar S., Karagöz S., Karayildirim T., Yanik J. Conversionof polymers to fuels in a refinery stream, Polymer
Degradation and Stability 75, 161-171, 2002.
[4] Serrano D.P., Aquado J., Escola J.M., Rodríguez J. M.
Influence of nanocrystalline HZSM-5 external surface on thecatalytic cracking of polyolefins, Journal of Analytical andApplied Pyrolysis 74, 353-360, 2005.
[5] Walendziewski J. Continuous flow cracking of wasteplastics, Fuel Processing Technology 86, 1265-1278, 2005.

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