The paper presents an analysis of gaseous emissions arising from the operations of printing using a printing process hot offset rotary. The first part presents the general characteristics of the process and the paint used. The following part shows the results of modelling the emission of pollutants according to the efficiency of the cleaning system, as well as depending on other parameters influencing the dispersion process impurities

Heryan, Andrzej

Krawczyk, Janusz

Wawszczak, Łukasz

Portal Czasopism Naukowych (E-Journals)

 JANUSZ KRAWCZYK
, ANDRZEJ HERYAN, ŁUKASZ WAWSZCZAK 
ENVIRONMENTAL INTERACTION ASSESSMENT  
OF VOC’S EMISSION FROM PRINTING PLANT  
HOT ROTARY HEAT-SET 
 
OCENA ODDZIAŁYWANIA NA ŚRODOWISKO 
EMISJI LZO W PROCESIE DRUKU  
GORĄCY OFFSET ROTACYJNY (HEAT-SET) 
 
 
 
A b s t r a c t  
The paper presents an analysis of gaseous emissions arising from the operations of printing 
using a printing process hot offset rotary. The first part presents the general characteristics of 
the process and the paint used. The following part shows the results of modelling the emission 
of pollutants according to the efficiency of the cleaning system, as well as depending on other 
parameters influencing the dispersion process impurities. 
Keywords: modelling of emissions, printing industry, rotary offset (heat-set) 
S t r e s z c z e n i e  
W pracy przedstawiono analizę emisji zanieczyszczeń (LZO) powstających w wyniku 
działalności zakładu poligraficznego wykorzystującego w procesie druku gorący offset 
rotacyjny. Część pierwsza prezentuje ogólną charakterystykę procesu oraz wykorzystywanych 
farb. W dalszej części przedstawiono wyniki modelowanie emisji zanieczyszczeń w 
zależności od sprawności układu oczyszczającego, a także w zależności od innych 
parametrów wpływających na proces dyspersji zanieczyszczeń. 
Słowa kluczowe: modelowanie emisji zanieczyszczeń, gorący offset rotacyjny 
DOI:   
                                                          
 PhD. DSc. Eng. Janusz Krawczyk, prof. CUT, Institute of Thermal and Process Engineering, 
Faculty of Mechanical Engineering, Cracow University of Technology. 

 DSc. Andrzej Heryan, MSc. Łukasz Wawszczak, Department of Scientific Research "Eko-Hera", 
Cracow. 
160 
 
1.  Introduction 
From the time of Johannes Gutenberg, who is considered to be one of the precursors of 
industrial printing method, printing processes have undergone many changes and 
modifications. Constant competition forces the use of ever newer solutions to optimise 
printing costs, while maintaining appropriate quality parameters. In the case of multi-
format printing, a frequently used technique is the process of printing by hot rotary heat-set, 
which enables to print significant amounts of paper in a relatively short time. Multi-format 
printing implies the use of the equipment of printing machines that are significant sources 
of emissions of dust and gas pollutants, mainly organic compounds. 
The paper presents an analysis of the emission of dust and gas emitted by modern offset 
printing, in which a large part of printing is done on automatic thermoforming machines. 
2.  Analysis of the sample printing offset in the context of emissions of dust and gas 
into the atmosphere 
2.1.  The object of the study 
The object of the analysed company is printing activity. 
The printing plant prints colour magazines, newspapers, advertising catalogues and 
leaflets, etc. A flat indirect (offset) printing technique with the fixation of paint at elevated 
temperature (heat-set) applies in the production process. 
The printing plant is located in one of the outlying districts of the city in an area planned 
for the activities of production and services. The immediate surroundings of the plant are 
the lands used for the purposes of business production and service. 
2.2.  Printing technology 
Web offset printing is a relatively cheap and quick way to obtain a large number of 
prints. Lightweight aluminium matrix formed on the drum printing sends an image on an 
intermediate drum with a rubber coating, which in turn transfers the image to paper. Hence, 
there is the second important definition of this technique – indirect print. This printing unit 
is capable of rotation at high speed. 
 
Fig. 1. Offset printing 
161 
 
Common use of colour web offset printing in addition to speed arises from the variety 
of possible use of media, i.e.: from coated paper (non-absorbent surface), the newsprint to 
cardboard (substrate absorbent). 
2.3. Raw materials used in the printing process 
Due to the volume of raw materials, which are used and the characteristics of the fusing 
mechanisms of printing inks in the process of web offset printing, determination of the 
characteristics of used inks is essential in order to assess the impact of the installation on 
the atmospheric air. Fusing mechanisms of inks of the type of heat-set occur due to the 
influence of the delivery of significant amounts of heat (blow heat, drying tunnels, which 
are heated by gas burning, etc.). Depending on the drying system, the paper has a 
temperature ranging from 90 to 150°C, which corresponds to a temperature of 200÷300°C 
of the drying agent. At these high temperatures, it evaporates mineral oil, which is a solvent 
for paints of heat-set type and water (moisture) from paper and wetting agents.  
For the production of heat-set paints, adhesives containing the composition of phenol-
formaldehyde resins and alkyd resins, polymerised linseed oil, mineral oil (fraction with a 
boiling point of 240÷300°C), colorants, tinters and excipients are used. Mineral oils used 
for the production of paints of the type heat-set are special species usually of naphthenic 
mineral oils. They are refined in such a way that they are almost odourless and colourless. 
Depending on the distillation, the boiling point is in the range of 240÷270°C, 260÷290 and 
270÷300°C. In the halftone paints, mineral oils vary in their boiling points because paints 
of different colours are to be traversed in the printing path of different distances. Therefore, 
a black colour which has the longest distance to go, has in its composition an oil having the 
lowest volatility. The yellow ink goes in turn the shortest possible route and, therefore, 
contains mineral oil with high volatility [1].  
2.4. Characteristics of emerging emissions 
For the production of heat-set paints, mineral oils containing aromatic compounds are 
used. In addition, wetting agents containing alcohol, iso-propyl or organic alternatives are 
used in the printing process. Depending on the drying system, it evaporates mineral oil, in 
varying amounts, which is a solvent of heat-set paint and water (moisture) from paper and 
wetting agents. The main pollution are therefore volatile organic compounds (VOCs) 
emitted in the installation in the amount of approx. 30 kg/h of VOC. 
Furthermore, due to the demand on the substantial amount of thermal energy for the 
drying process of the paper, the fuel is typically used for natural gas, in which the products 
of combustion (mainly nitrogen oxides, carbon monoxide, carbon dioxide) also flow to the 
atmosphere.  
2.5. Legal requirements relating to the issue of emerging contaminants 
Legal requirements for environmental protection regulate the Framework Law of 27 
April 2001. Environmental Protection Law (Polish Journal of Laws of 2013 item. 1232, as 
amended.) and implementing acts to the above Law. According to the Regulation of the 
Minister of Environment of 26 January 2010 on reference values for certain substances in 
the air (Polish Journal of Laws of 2010 no. 16 item. 87) [2] plant, which leads pollution in 
162 
 
an organised manner to the atmosphere is obliged to use solutions that will not exceed the 
permissible reference value, ice. appropriate normative values concerning excess emissions 
will be saved. 
Moreover, in the case of large printing plants, which consume large quantities of raw 
materials (this translates into considerable use of VOC), additional requirements apply for 
the protection of atmospheric air as defined in the Regulation of the Minister of 
Environment of 4 November 2014 on emission standards for certain types of installations, 
combustion plants and equipment incineration or co-incineration of waste [3]. The 
processes carried out in the system used in this printing plant include (in accordance with 
Annex 7 to the above regulation to hot offset rotary process, which identified the following 
emission standards (Annex 8 point 1): 
For VOC usage> 25 Mg / year 
S1 = 20 mg / m
3
 VOC 
(counted on organic carbon). 
2.5. Methods of reducing emissions of pollutants 
Systems of injecting air containing solvents are usually designed to maintain an 
adequate atmosphere within the workspaces and equipment significantly below the 
permissible concentrations of pollutants. Deriving solvents from the key sources can lead to 
disposal system of waste gases because of the need to comply with regulations on 
environmental protection. When designing injecting systems, some things must be taken 
into account: 
 the amount of the discharged air, 
 level of solvent, 
 type of utilisation, its cost-effectiveness and impact on the environment, 
 number of working hours per year. 
 
When injecting a large amount of air relative to the solvent increases the size of 
reduction system, and may increase the amount of energy required as drive, which supports 
combustion. In the case of large printing plants using web offset printing generally used 
methods are based on oxidation of pollutants through the use of thermal afterburners. In 
certain cases, it is reasonable to use catalytic afterburners, which through the use of a 
catalyst operate at lower temperatures than thermal afterburners (this translates into energy 
savings). 
Moreover, in the case of large printing plants, there are also solutions in which every 
single print line may have a dedicated system of waste gas treatment. For example, if it is 
integrated into the dryer(s), the system allows for easy use of heat or exhaust gases for 
heating the air in the dryer. Printing presses in such a case depend on the central system of 
waste gases. 
2.6. Sources of emissions in the tested offset printing plant 
When injecting pollutants into the air is related to the functioning of the basic 
technological processes (sources of emissions from the production equipment). Vapours 
produced during drying of the printed paper web are extracted on machines and routed to a 
163 
 
thermal afterburner, which reduces pollution. Burners with the installed thermal capacity in 
the range 850÷1600 kW function for particular drying tunnels of web offset printing 
machines for drying the printed paper. 
2.7. Maps of the distribution of concentrations of selected pollutants around the premises 
Simulations of the changes of individual pollutants concentrations in the atmosphere 
were made using modelling software a steady-state Gaussian plume model on the basis of 
measurements of pollutants emissions carried out by an accredited laboratory according to 
Polish reference methodology [2]. The resulting simulations are expressed as map of spatial 
concentration distribution and demonstrated in Figs. 2 a and b to show the greatest 
concentration of major pollutants in the vicinity of the plant. 
 
Fig. 2a. The map showing isolines of the peak concentrations of selected pollutants 
(aromatic hydrocarbons) 
 
Fig. 2b. The map showing isolines of the peak concentrations of selected pollutants 
(aliphatic hydrocarbons) 
164 
 
3.  Calculation of the concentrations of dust and gas pollutants emitted into the 
atmosphere depending on changes of selected technical parameters of the installation 
According to the measurements carried out by the accredited laboratory, the afterburner 
efficiency in the test plant is approx. 99% of VOC. The tables 1 and 2 show how the change 
in volume would have affected the maximum concentration of emitted pollutants (VOC) by 
using afterburner with a different efficiency, as well the change of peak levels when 
choosing the other technical characteristics of the emitter (height, diameter) was presented.  
This simulation was performed to investigate whether the use of relatively cheap and 
fast to carry out technical solutions (change in height or diameter of the emitter) instead of 
afterburners with extremely high efficiency, can significantly reduce the impact of printing 
plant on the atmospheric air. 
T a b l e  1  
The average increase in the concentrations of pollutants compared to the actual 
afterburner efficiency 
Pollution 
Maximum concentration of impurities (depending on the 
efficiency of the afterburner) [mg/m3] 
95% 96% 97% 98% 99% 
Benzene [1] 2.03 1.84 1.64 1.44 1.24 
Xylene [2] 2.08 1.74 1.39 1.04 0.69 
Styrene[3] 1.09 0.90 0.70 0.50 0.30 
Toluene [4] 1.69 1.41 1.12 0.84 0.56 
Aromatic hydrocarbons [5] 14.42 11.71 8.99 6.28 3.57 
Ethylbenzene [6] 1.21 1.02 0.82 0.62 0.42 
Aliphatic hydrocarbons [7] 31.34 25.43 19.53 13.63 7.72 
      
The average increase in the 
concentrations of pollutants 
compared to the actual  
afterburner efficiency [%] 
+ 218.28 + 163.67 + 109.10 + 54.52 – 
 
When changing the performance of an afterburner from 99% to 95%, we can observe up 
to 218% average increase in the concentration of pollutants in the air. Even in the case of 
restriction of performance of afterburner from 99% to 98% we can observe up to 50% 
average increase in peak concentrations in the atmosphere. A summary of calculation 
results is also presented graphically in the chart below: 
165 
 
 
Fig. 3. A graph showing maximum concentration of selected impurities depending on the 
performance of afterburner 
The change of the height of the emitter can affect the concentration pollutants as 
follows: 
T a b l e  2  
The average decrease in the concentrations of pollutants depending on the height of emitter of 
afterburner 
 
Maximum concentration of impurities 
(depending on the amount of boost emitter) [m] 
14 16 18 20 22 
The average decrease in the 
concentrations of pollutants 
depending on the height of 
emitter of afterburner [%] 
– - 6.05 - 11.32 - 14.36 - 18.31 
 
When changing the diameter of the emitter, concentrations of pollutants can achieve the 
values as follows: 
T a b l e  3  
The average decrease in the concentrations of pollutants depending on the diameter of emitter 
of afterburner 
 
Maximum concentration of impurities 
(depending on the diameter of emitter) [m] 
1,4 1,3 1,2 1,1 1,0 
The average decrease in the 
concentrations of pollutants 
depending on the diameter of 
emitter of afterburner [%] 
– - 2.46 - 4.96 - 6.30 - 9.18 
 
166 
 
4.  Conclusions 
 From the presented analysis of emissions (VOC) resulting from the operations of the 
printing plant using hot offset, in a printing process, we can conclude that the 
concentrations of VOCs are within the range of permissible emission standards. 
 Change of the performance of afterburner to a varying degrees results in the maximum 
concentration of each pollutant. 
 Change of performance of afterburner from 99% to 98% causes – according to 
modelling, which was carried out – more than 50% increase in peak concentrations of 
impurities. 
 Change of the diameter of the emitter by about 0.2÷0.4 meter or change of the height of 
the emitter by 2 to 6 meters allows for a reduction of the maximum concentrations of 
pollutants by approx. 5 to 15%. 
 In the case of small deviations from the normative reference values of pollutants in 
ambient air can be considered as a method to reduce nuisance on a change of parameters 
of emitter (height, diameter). 
 
R e f e r e n c e s  
[1] Jakucewicz S., Farby drukowe, Michael Huber Polska Sp. z o.o., Wrocław 2001. 
[2] Regulation of the Minister of Environment of 26 January 2010 on reference values for 
certain substances in the air, Polish Journal of Laws of 2010, no. 16, item 87. 
[3] Regulation of the Minister of Environment of 4 November 2014 on emission stan-
dards for certain types of installations, combustion plants and equipment incineration 
or co-incineration of waste, Polish Journal of Laws of 2014, vol. 1, item 1546. 
 


Environmental interaction assessment of VOC’s emission from printing plant hot rotary heat-set

http://www.ejournals.eu/sj/index.php/Cz/article/download/6716/pdf_837

Environmental interaction assessment of VOC’s emission from printing plant hot rotary heat-set

Abstract

Similar works

Full text

Available Versions

Portal Czasopism Naukowych (E-Journals)