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Polymer waste safe disposal by incineration in electrostatic field
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AFE 2021
IOP Conf. Series: Earth and Environmental Science 937 (2021) 042063
IOP Publishing
doi:10.1088/1755-1315/937/4/042063
1
Polymer waste safe disposal by incineration in electrostatic
field
I A Zyryanov*, A P Pozolotin, and A G Budin
Vyatka State University, Department of Engineering Physics, Moskowskaya Street,
36, 610000, Kirov, Russia
E-mail: cynepcoyc@rambler.ru
Abstract. Polymer waste disposal of is one of the most pressing problems of our time. The
incineration method is widespread, but it has its drawbacks. Problems during the polymer waste
combustion, which include low combustion efficiency, combustion products toxicity,
significantly reduce the possibility of waste disposal incinerators using. In this regard, the work
considers the use of an electrostatic field to optimize the combustion process. Experimental
studies of the electrostatic field influence on the substances difficult for disposal (polyethylene,
polypropylene, polystyrene, rubber) combustion have been carried out. The possibility of
increasing the polymer waste combustion rate, flame temperature, and combustion efficiency is
shown.
1. Introduction
The solid waste disposal problem is currently very acute. According to the Discovery Research Group
analytical report for 2019, since the beginning of the XXI century, the solid waste generation volume in
the world has doubled, reaching 1.3 billion tons in 2013. By 2025, the volume of solid waste can reach
2.2 billion tons, and by 2050 - 2.72 billion tons. Over the past fifteen years, the volume of solid waste
generation in the Russian Federation has doubled. In 2016, its value amounted to 52.4 million tons, of
which only 2.3% (1.0 million tons) were sent for neutralization and destruction, including incineration.
The main part of solid waste - 88.7% (47.5 million tons) - went to dumps and landfills. Due to the fact
that landfills are often overcrowded, solid waste incineration is one of the most efficient disposal
options. Incineration allows to reduce the solid waste volume by 90%, and the mass - by 75%,
completely biologically stabilizing the raw materials, as well as ensuring the heat and electricity
generation.
The incineration of polymer waste, as well as various rubbers, etc., gives rise to an acute problem of
environmental pollution by incomplete oxidation products, which greatly limits the waste incineration
plants use. In this regard, an important scientific and technical problem is the search for methods to
improve the environmental friendliness of the polymer waste combustion process. In this work, it is
proposed to experimentally investigate and substantiate the effectiveness of the combustion optimization
by using electrostatic fields. In the literature [1-3], the effectiveness of the electrostatic field influence
on the number of polymers combustion macroparameters is shown. However, the work results indicate
a sharp dependence of the effect on the polymer nature, which determines the chemoionization reactions
in the flame and the combustion mode. This circumstance does not allow predicting the field effect on
the polymers combustion for which this technology has not yet been applied.
AFE 2021
IOP Conf. Series: Earth and Environmental Science 937 (2021) 042063
IOP Publishing
doi:10.1088/1755-1315/937/4/042063
2
In order to identify individual for each polymer and general regularities of the field influence on the
combustion completeness, as well as to combine various polymeric materials for co-combustion, the
main work purpose is to study the electric field effect on the combustion parameters.
The nature and types of polymers in municipal solid waste differ depending on many factors such as
use conditions, functional requirements, etc. The most common polymers used in everyday life, as well
as the most dangerous products of their incomplete oxidation, are shown in Table 1 [4-6].
Table 1. Used polymers.
Polymer
Usage
Incomplete combustion products
Polyethylene
Packages, films, containers,
etc.
СO
СO2
Acrolein
Toxicity index– 1,61
Polypropylene
Packaging material, disposable
syringes, containers.
СO
СO2
Formaldehyde,
Acetaldehyde,
Acetic acid
Polystyrene
Disposable dishes, toys, Petri
dishes, pipettes
СO
CO2
Styrene
Benzopyrene
Rubber
Tires, rubber products
СО2
Sulfur
Benzopyrene and other carcinogens
Literature data [5-7] show that the incomplete combustion products of these materials contain
substances of 1-3 hazard class. However, the combustion products composition is significantly
influenced by the thermal decomposition conditions of polymer materials (heating rate), as well as the
oxidation features of the gases formed in the flame (temperature, oxidizer amount) [7-8].Therefore, these
materials were chosen as investigation objects of the electrostatic fields influence on combustion
parameters.
On the other hand, municipal solid waste, even after sorting, is a potential fuel with a highly
heterogeneous chemical composition (fire retardants, dyes, dispersed impurities, etc.). Additives in
household plastics can significantly alter the combustion process, making them difficult to burn. In this
case, the electric field effect can effectively change the polymers combustion rate [1], which is also
investigated in this work.
2. Experimental setup and experimental technique
The experiments were carried out on a specialized experimental setup. The setup diagram is shown in
Figure 1. The installation includes: analytical weighing scales VSL-200, on which an insulated sample
holder is installed, an electrodes system and a temperature measurement system.
An electric field is created between flat grid electrodes. The lower electrode is mounted on the sample
holder, the upper one is above the flame. The potential difference between the electrodes is created by
the high voltage source HCP 35-35000. The electrodes configuration was chosen due to the maximum
influence effect on combustion [1]. With this electrodes configuration, a homogeneous electrostatic field
is created in the combustion zone, the parameters of which (value and direction of the electrical tension)
can be varied. Depending on the electrodes polarity: the field directed towards the fuel surface (the upper
electrode is positive) is indicated by -
E
, the field directed from the fuel surface (the upper electrode
is negative) -
E
.
The polymer sample for combustion is placed in the quartz glass, mounted on the bottom electrode.
Sample mass measurements are recorded by a weighing scales connected to a computer with a frequency
AFE 2021
IOP Conf. Series: Earth and Environmental Science 937 (2021) 042063
IOP Publishing
doi:10.1088/1755-1315/937/4/042063
3
of 4 measurements per second. Determination of the combustion rate was carried out by the continuous
weighing method [1]. For clarity, the results are presented in relative coordinates u/u0.
The system for the flame temperature in an electrostatic field measuring includes a thermocouple
and a positioner. A chromel-alumel thermocouple with a diameter of 60 μm was used in the work. The
thermocouple is positioned in the sample symmetry center using a positioning device, then after the
sample ignition it moves vertically to find the temperature maximum.
Figure. 1. Experimental setup for studying the electrostatic field effect on
the mass combustion rate and flame temperature.
The polymer sample for combustion is placed in the quartz glass, mounted on the bottom electrode.
Sample mass measurements are recorded by a weighing scales connected to a computer with a frequency
of 4 measurements per second. Determination of the combustion rate was carried out by the continuous
weighing method [1]. For clarity, the results are presented in relative coordinates u/u0.
The change in the combustion completeness is estimated by the formula (1) presented in [2]:
e
B
(1)
where ηe and η are the combustion completeness in the field and without the field, respectively.
3. Experimental results
The electrostatic field effect on the flame shape of the studied polymers is presented in Table 2. With
E
polarity for all polymers, there is a slight increase of the flame height and the bright yellow glow
region. For
E
polarity, the polypropylene and polyethylene flame is pressedtowards the polymer
surface, forming a sphere; for polystyrene and rubber an explosive combustion mode is observed, which
is characterized by flame pulsations [3]. It should be noted that for the explosive combustion mode case,
the flame soot tail disappearance is observed.
AFE 2021
IOP Conf. Series: Earth and Environmental Science 937 (2021) 042063
IOP Publishing
doi:10.1088/1755-1315/937/4/042063
4
Table 2. Flame shapes.
Polymer
E =0 kV/m
E
=200 kV/m
E
=200 kV/m
Polypropylene
Polyethylene
Polystyrene
Rubber
Figure 2 shows the field effect on the relative combustion rate results (negative electrical tension
corresponds to the direction -
E
, positive -
E
).
The experimental results indicate that the electrostatic field has the strongest effect on the combustion
rate at
E
, in particular, for rubber and polypropylene the combustion rate increases by 300-400% at
field strength up to 200 kV/m, for polystyrene by 150-180%. At
E
, the effect of the field is weaker:
AFE 2021
IOP Conf. Series: Earth and Environmental Science 937 (2021) 042063
IOP Publishing
doi:10.1088/1755-1315/937/4/042063
5
for polypropylene, the combustion rate is intensified to 200% at field strength up to 200 kV/m, for
polystyrene up to 150%, the field effect on rubber under these conditions is practically not noticeable.
With both electrodes polarities, the field effect on the polyethylene combustion is rather weak. However,
for the case
E
at 100 kV/m, a decrease in the combustion rate by 50% is observed.
Figure. 2. Combustion rate relative change in the fields of different strengths.
Figure 3 shows the maximum flame temperature on the field strength dependences. At
E
, an
increase in the maximum flame temperature is observed: for rubber by 60 °C, for polystyrene by 270
°C, for polypropylene by 80 °C with field strength values up to 150 kV/m. For polyethylene, the
temperature does not increase within the experimental error. At
E
for polyethylene, a decrease in
combustion temperature by 100 0C is observed. For the rest of the polymers, due to the combustion
instability, no unambiguous temperature data could be obtained.
Figure. 3. Relative change in the maximum flame temperature in fields of different strength.
The change in the maximum flame temperatures was used to estimate the relative change in the
combustion completeness β (Figure 4).
AFE 2021
IOP Conf. Series: Earth and Environmental Science 937 (2021) 042063
IOP Publishing
doi:10.1088/1755-1315/937/4/042063
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Figure. 4. The relative change in the combustion completeness in fields of
different strengths.
As can be seen from the presented graphs, the combustion completeness when an electrostatic field
E
is applied increases: for rubber and polypropylene by 8%, for polystyrene by 27% at field strength
up to 150 kV/m. At
E
for polyethylene, the combustion efficiency decreases by 12%.
4. Discussion of results
To explain the electrostatic field action on combustion parameters mechanism, it is necessary to take
into account the field effect: on the flame shape, on the chemical reactions kinetics (which is responsible
for the flame temperature), on the polymer melt properties as a dielectric, on the thermal decomposition
of the polymer in the melt [1-3].The resulting effect depends on the contribution magnitude of the listed
processes from the standpoint of intensification and inhibition. The direction of field
E
practically
does not deform the polymer flame, however, an increase in the maximum temperature and burning rate
is observed for rubber, polystyrene and polypropylene; the combustion process for polyethylene does
not change. The direction of the field
E
for polystyrene and rubber leads to an explosive combustion
mode, and as a consequence, the combustion rate increases. For polypropylene and polyethylene such a
regime is not observed, however, for polyethylene combustion inhibition is observed, and the
combustion completeness decreases. The results obtained confirm the hypothesis of the need for an
individual approach to the polymers combustion in electrostatic fields. At the qualitative level, the
polymers combustion completeness increases; however, to complete the picture, it is necessary to study
the field effect on the toxic emissions level.
5. Conclusion
Thus, the electrostatic field use can be one of the most effective methods for intensifying the polymer
waste combustion. Since it can increase the flame temperature, combustion rate and completeness, this
method improves the combustion environmental performance. The electrostatic field use in combination
with other methods to improve the combustion environmental friendliness (afterburners use, reaction
zone turbulization, installation of filtering equipment, etc.) will significantly develop and make the
technology of waste incineration safe.
References
[1] Reshetnikov S M, Pozolotin A P and Zyryanov I A 2013 Polymers combustion in an electrostatic
field Vestnik of the Samara State Aerospace University 41 p 8
[2] Zyryanov I A, Pozolotin A P, Budin A G and Kantor E V 2019 The possibility of reducing the
AFE 2021
IOP Conf. Series: Earth and Environmental Science 937 (2021) 042063
IOP Publishing
doi:10.1088/1755-1315/937/4/042063
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toxicity of gaseous emissions of power plants by the effect of an electrostatic field on the
organic fuel combustion zone Theoretical and Applied Ecology 1 pp 88-93
[3] Reshetnikov S M, Zyryanov I A and Pozolotin A P 2013 Abnormal behavior of alkanes and
rubbers during combustion in an electrostatic field Vestnik of the Kazan State Technical
University 16 pp 44-48
[4] Ilichkin V S, Smirnov N V, Eliseev Y N, Belousov Y Y, Zaytcev A A and Komova M A 2005
Determination of the materials combustion products toxicity index by the experimental
calculation method Fire and Explosion Safety 14 pp 29-34
[5] Krivosheeva L V, Hitrova I A, Ogloblina A M, Kirsanov K I, Lesovaya E A, Ivanov A A,
Belitskiy G A, Dmitrieva O V and Yakubovskaya M G 2016 Carcinogenic hazard of smoke
emissions from open burning of waste polymer and latex products International Journal of
Applied and Basic Research 1 pp 162-170
[6] Maksimov A M 2003 Creation of a system for collection, processing and disposal of used tires
and other rubber products in the Russian Federation Motor transport enterprise 12 pp 39-41
[7] Reshetnikov S M and Reshetnikov I S 2014 Combustion Anathomy (Moscow: NGSS) p 247
[8] Bazunova M V and Prochuhan Y A 2008 Methods for recycling waste polymers Bulletin of
Bashkir University 13 p 11