Tenebrio molitor as substrate for anaerobic digestion

Petra WOJNAROVÁ, Jiří RUSÍN
VŠB - TU Ostrava, Institute of environmental technology, 17. listopadu 2172/15, 70833 Ostrava Poruba, Czech Republic
e-mail: petra.wojnarova@vsb.cz

The range of organic substrates suitable for anaerobic production of biogas and bio-fertilizer is limited. The use of insect biomass for this purpose can be a feasible future solution, as this biomass is characterized by high mass gains and high lipids and protein content. The insects can be bred while being fed by difficult to degrade waste biomass or by common food biowaste. Hibernation in hypothermia allows humane way of killing insects before processing. Nowadays, the mealworm beetle (Tenebrio molitor) is being bred for the production of food. Its use for energy production should also be considered. To verify the energy balance of insect breeding and following production of biogas from its biomass it is necessary to have knowledge about production of biogas and methane. This paper discusses the results of the biochemical methane potential test of the biomass of the Tenebrio molitor larvae.

Keywords: insect, Tenebrio molitor larvae, anaerobic digestion, biochemical methane potential test

Thermal treatment of by-product from cement-bonded particleboards production for further use

Tomas MELICHAR, Matej LEDL, Jiri BYDZOVSKY, Amos DUFKA
Brno University of Technology, Faculty of Civil Engineering, Veveri 331/95, 602 00 Brno, Czech Republic,
 e-mail: melichar.t@fce.vutbr.cz, ledl.m@fce.vutbr.cz, bydzovsky.j@fce.vutbr.cz, dufka.a@fce.vutbr.cz

This paper presents the issue of thermal treatment of by-products arising in the production of cement-bonded particleboards. These by-products are formed during the processing of cement-bonded particleboards (cutting and grinding). The aim of the presented research was to evaluate the effect of thermal treatment on the properties of the mentioned by-products and then cement composites with containing these compounds. The reason for the research was to assess the possibility of activation of by-products from the production of cement-bonded particleboard with regard to participation during the formation of the structure of the cement matrix. The heat treatment of the by-products took place at temperatures of 1000 °C and 1200 °C. Thermally treated offcuts and dust (from two collection towers) were applied to cement composites as a partial cement replacement in amounts of 10 and 25%. Subsequently, the influence on physical-mechanical properties of mortars including changes in chemical, resp. mineralogical composition and microstructure was evaluated. The properties and behaviour of the materials were monitored and evaluated at the age of 28 and 90 days of curing.

Keywords: Cement-bonded particleboard, by-product, thermal treatment, cement mortar, microstructure, gross heat of combustion, mechanical resistance.

Cut Flowers and Greenhouse-Gas Production during the Landfilling of Biodegradable Municipal Waste

Petr BURYAN¹, Šimon BURYAN^2
1 University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, CR,
e-mail: buryanp@vscht.cz
² University of Economics Prague, CR, W. Churchilla 1938/4, 130 67 Prague 3, CR, e-mail: simon.buryan@vse.cz

Cut flowers create a pleasant atmosphere, influence the aesthetic feeling of the perception of many life situations. Unfortunately, faded flowers end at landfills, where they are subject to anaerobic digestion, producing significant amounts of greenhouse gases. In addition, their use also involves air and car transport and thus carbon-dioxide emissions.

The total emissions from deposited roses is 0.41 mil. m³ methane and 28492 t CO₂, from deposited chrysanthemums 0,13 mil. m³ methane and 9 149 t CO₂, and from carnations 0,04 mil. m³ methane and 2 624 t CO₂.

A summary of the hidden ecological contexts associated with greenhouse gases in selected species of cut flowers is provided below.

Keywords: greenhouse gas, municipal waste, cut flowers

Analysis of a practical approach to the concept of sustainable development in a manufacturing company in the automotive sector

Andrzej PACANA^1*, Karolina CZERWIŃSKA¹, Lucia BEDNÁROVÁ² , Jana DŽUKOVÁ^2
1 Rzeszow University of Technology, The Faculty of Mechanics and Technology, al. Powstancow Warszawy 8; 35-959 Rzeszow, Poland
² Technical university of Košice, FBERG, Letná 9, 04001 Košice, Slovakia
* Correspondence: app@prz.edu.pl; Tel.: +48-178-65-1390

The sustainable operation of production enterprises can contribute to their attractiveness as well as strengthen their competitive position in the market. The implementation of these principles enables goods and services to be produced and provided in a way that uses processes and systems that reduce environmental impact. The article analyses the idea of sustainable development in building the value of a socially responsible production company. The aim of the article was to present the importance of sustainable development issues in relation to the functioning of one of the companies from the automotive sector and to conduct an analysis and demonstrate the benefits of designing and creating a department for secondary metal smelting - aluminum chip smelting.

Keywords: production management, sustainable development, ecological motorization, ecological innovations

Numerical and Experimental Investigation of the Effect of the Mineral Wastewater and Improved Dune Sand Subgrade and Pavement Rutting

Mohammad Mehdi KHABIRI ^*, Sadegh Heidari BAFGHI ², Bahareh EBRAHIMIALAVIJEH
Faculty of Civil Engineering, Yazd University, Yazd, Iran
*Corresponding author: mkhabiri@yazd.ac.ir

Nowadays, along with an increase in mine activities, pay attention to environmental issues to achieve the sustainable targets has gained a special place. On the other hand, an increase in various types of natural destructive pollutants and also increasing the use of industrial and drinking water by human societies is deniable. Using mineral  wastewater and mine tailings in road and building construction projects will provide great help for the environment. In the present study, stabilization of dune sand, which is one of the loose soils in road construction projects, has been investigated using a kind of mineral wastewater at three weights 7, 14 and 21 percentages by dry weight of soil. For this purpose, compaction, compressive strength, direct shear and CBR tests have been done to investigate the effect of this material on the resistance parameters of dune sand. The results showed that the addition of mineral wastewater to the soil, led to a decrease and an increase in optimum moisture content and maximum dry density, respectively. The addition of mineral wastewater increases the compressive strength and displacement and as a result of an increase in the weight percentage of mineral wastewater, the number and the depth of failure cracks have been reduced Increase the mineral wastewater from 14 to 35%, has led to an increase in compressive strength of more than 39%. By checking the SEM images, it was found that the reduction in the holes and porosity of the soil, as well as an increase in interlocking between the particles, are the factors of increase in strength parameters. To investigate the application of this method in road construction, the effect of stabilized layer and the mineral wastewater content of the settlement has been studied. The results of numerical analysis show that add 7 and 14 percent of mineral wastewater reduces the settlement compared with unstabilized sample. Therefore, the probability of rutting failure of subgrade will be reduced. Finally, the recommended function of Response Surface Methodogly for settlement in terms of the two variables includes layer width and mineral wastewater content has been defined using the response level analysis method.

Keywords: Mineral wastewater, subgrade stabilization, shear strength, compressive strength, dune sand, rutting.

Use of waste marble sludge as a source of calcium for self-healing concrete with the use of bioremediation

Zdeněk PROŠEK, Pavla RYPAROVÁ, Pavel TESÁREK
Czech Technical University in Prague, Faculty of Civil Engineering, Thákurova 7, 166 29 Praha 6, Czech Republic

The presented article is focused on the use of recycled materials in construction in the design of a new mixture of cement paste with bio-remediation effects. The paper presents the method of bio-remediation of concrete, respectively. cement matrix, from the point of view of additional application of bacteria and culture medium to the surface of the damaged sample. The issues from the point of view of application in the Czech Republic, the selection of the most suitable bacteria and culture medium, the issues of monitoring bio-remediation using electron microscopy and the use of micronized waste marble as a source of calcium in remediation processes are specified. The results show that micronized marble has a positive effect on the bioremediation of the cement matrix.

Keywords: Cement composite, waste marble sludge, microscopy, recycling, bio-remediation.