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Paper waste is a raw material for a lot of products with different added value. The engineering, economic and environmental aspects of paper waste recycling are analysed for production of composite material, cellulose nanofibers and nanocrystals, bricks with paper components, porous carbon, film of biopolymer, enzymatic sugar and bioenergy: bioethanol, hydrogen and biofuel. Through multicriteria analysis, it was possible to determine the most feasible paper waste recycling product in case of four product groups: egg packaging boxes, cardboard, reused paper, cellulose nanomaterials (nanofibers and nanocrystals). The production of cellulose nanofibres and cellulose nanocrystals has an advantage over egg packaging and cardboard production as well as reusable paper.

The scope of the Nordtest method is to evaluate the moisture buffer value (MBV) of materials exposed to indoor air. The test is intended to simulate daily variations with relative humidity (RH) between 75 % during 8 hours and 33 % during 16 hours. The specimens follow a recipe that consists of waste paper, glue and water. Specimens made of paper plaster were covered with different colours. The results of the experiment showed that the type of paint used and the number of layers applied affected the MBV. Natural colours have a better moisture permeability than chemical paints, but the number of natural colour layers affects the MBV. The higher the number of layers, the lower the MBV.

The search deals with the possibilities of increasing the fire resistance of paper, cardboard or paperboard. The article includes the principles of fire retardancy as well as requirements for a suitable preparation and lists substances and mixtures which, according to the literature, are/were used in the manufacturing process or after-treatment of paper products. The article is also continuously supplemented by examples from the patent literature.

High sensitivity of lead to organic compounds leads to degradation of historical lead objects stored in the depositories of museums or archives. High concentration of organic compounds in the atmosphere of depositories is caused by degradation of organic materials (wood, glue, leather, paper). Organic materials are stored together with lead objects or they are used as a packaging material. This study was aimed on the influence of packaging material properties to aggressiveness towards lead with different state of surface by the resistometric method. The results showed that aggressiveness of packaging material is determined by a complex influence of material properties. The presence of corrosion products on the lead surface significantly increases its sensitivity to organic compounds.

This paper introduces cloud manufacturing (CMfg) as a new manufacturing paradigm that joins the emerging technologies – such as the Internet of Things, cloud computing, and service-oriented technologies – for solving complex problems in manufacturing applications and performing large-scale collaborative manufacturing. Using scientific publications indexed in Scopus database during the period 2012–2017, the concept and fundamentals of CMfg are presented and discussed given the results of the most recent research. While focusing on the current state of the art, the recent research trends within CMfg concept were also identified. The review involved the methods of bibliometric analysis and network analysis. A prototype of CMfg and the existing related work conducted by various researchers are presented, and the map of co-occurrence is introduced to indicate the most commonly occurring issues related to the “cloud manufacturing” term. The VOSviewer software was used for this purpose. Finally, cloud-based manufacturing areas for further research are identified.

The aim of this study is to use material flow cost accounting (MFCA) to assess the level at which cleaner production (CP) can improve both environmental and economic performance of an organization. Higher energy and raw material prices are causing CP to grow in relevance and importance. The amount of waste to landfill is increasing steadily. Most companies are using inefficient processes and technologies that are obsolete resulting in higher production costs, which, in turn, affect their profitability and competitiveness. This study was a case study based on a paper manufacturing company using an exploratory qualitative and quantitative research methodology. The MFCA approach was used to assess the efficiency of the steam production process using coal-fired boilers. The results indicated that the process was inefficient resulting in significant negative environmental and economic impact. Environmental costs were hugely underestimated by management, as non-product output costs were not included as part of environmental costs calculated by company. Benefits and barriers to CP was also brought to the forefront at the conclusion of this research.

Comfort properties of garments are influenced by fiber properties, fabric properties, and applied finishes. Denim garments are widely used apparels, and they are processed with different industrial finishing treatments. Finishing treatments and fabric weight have a great influence on the thermal comfort of denim fabrics. The aim of this paper was to evaluate the effects of finishing treatments (rigid, bleaching, resin, softener) on the thermophysiological comfort and moisture management properties of denim fabrics considering three weight categories (light, medium, heavy). The thermophysiological comfort (thermal resistance, thermal absorptivity, air permeability, water vapor permeability tests) and liquid moisture transport capabilities (transfer wicking and drying behavior of fabrics) were measured and analyzed statistically. As a result of the study, fabric weight and finishing had been found to be important parameters for the comfort properties of denim fabrics. As a conclusion, it could be stated in the light of the results that the fabric weight type (light, medium, heavy) had a significant impact on the fabric thermophysiological comfort properties.

Carbon neutrality has become a goal of European Union countries as they held agreement on the European Green Deal; the goal needs to be achieved by 2050. To achieve this goal production industry plays major role as this sector produces considerable amount of greenhouse gas emissions. This paper analyses processes within fish processing industry as the consumption of fish products has increased; therefore, production rate in this area also has been growing. Even more, the consumption of fish products per capita is forecasted to keep increasing for at least the next further years as fish products are great protein source. Thus, it is important to improve efficiency in the fish processing industry, to reduce the amount of emissions, waste and pollution produced in the industry, to evaluate the use of water and energy as well as the resources used in order to achieve sustainable production and carbon neutrality. Data envelopment multicriteria analysis method was used in this research to evaluate energy efficiency in the fish processing industry within sterilization process. The results have shown that the full water immersion autoclave and the water and steam autoclaves are the most efficient from four technologies analysed.

This paper presents the technology of production of synthetic fibrous materials from PET-raw by vertical blowing method. Fibre production by vertical blowing method is accompanied by complex and specific phenomena; therefore, development of new progressive technologies, high-performance machines and units for producing such materials is impossible without process modelling, which can significantly reduce the number of natural tests, cost and designing time and select optimal operating modes. Molten material motion in the melting unit of the hydrostatic type is determined by means of Poiseuille formula. Furthermore, the paper has proven that the melting unit has the greatest impact on process productivity by means of outlet radius and the pressure change of compressed air acting on the molten material surface. Increase in the height of the molten material column in the main cylindrical chamber of melting unit also leads to an increase in process productivity.

The olive oil processing industry’s liquid effluents (OMW) have a polluting capacity for the ecosystems. This study aimed to evaluate the physicochemical quality of OMW of two varieties of separated and combined olives cultivated in Khenchela Eastern Algeria, from the cold extraction of the olive oil extraction system. These was to determine their degree of pollution and biodegradability during one year of storage at ambient temperature to recommend the correct treatment for each storage time. Results of the measured parameters pH, EC,TSS percent, H2O percent, lipids, DM, OM, MM, VM, COT percent, NTK percent, C/N, BOD5, COD, BI, TOM, BOD5/COD show that wastewater from olive oil mills has an acid pH, and they are very loaded with organic matter evaluated in terms of COD and BOD5, quite filled with minerals. The storage of olive mill waste can reduce progressively the pollution caused by this waste. Whereas during one year, the reduction rate of COD, BOD5, TOM, BI, is respectively 29.4%, 54.8%, 39.16%, 54.2%, but C/N, BOD5/COD continue to increase as well as pH that continues to decrease during the storage. Accordingly, storing olive mill waste during a year reduces its pollution rate, so it is slowly biodegradable. When disposing of it, an adequate treatment procedure must be required to protect the environment.

The research purpose was to develop the basics for silage preparation by vacuuming with the use of flexible polymer containers and estimating silage quality. The analysis of modern systems used for silage preparation and storage showed that the main disadvantages include the high storage and preparation costs, and losses of silage weight and nutrients by 3–25% after opening of storage facilities. To eliminate these disadvantages, the basics for preparing the silage by vacuuming in flexible polymer containers that can be transported and stored with optimum volume have been studied and developed. The study pursuits its goals by observing the changes in density and degree of silage compaction caused by the vacuum pressure and deadweight. A comparative estimation of silage quality indices was conducted by means of chemical analysis of silage specimens. The results show graphical dependencies of changes in silage volume and density at vacuum pressure up to 60 kPa. Moreover, a comparative assessment of quality indices of silage specimens prepared by vacuuming in soft containers, and traditional method using trenches was conducted. The reliability of results for silage storing quality in a vacuum container was achieved by fivefold test repetition within 2 years. Comparison of silage quality indices obtained using vacuum technology and traditional method showed improvement in favour of the proposed method: dry matter by 2.05%; protein by a factor of 1.47; nitrogenous substances by 1.37; starch by 1.56; calcium by 1.83; phosphorus by 2; digestible protein by 1.24; feed unit by 1.31; exchange energy by 1.16, which was achieved thanks to the elimination of succus leakage.

In this study, the effects of the lacquer applied to the printing materials which were printed by electrophotographic printing method on printing quality were investigated. In practice, printing materials with the same weight and different optical properties were used and the study was carried out in three stages. The optical and physical properties of the printing materials used in the first part were determined, in the second part, the printing of these materials by electrophotographic printing method and printability tests were performed. In the third chapter, matte and glossy lacquers were applied to these printed materials and printability tests were repeated. As a result of the study, it was observed that the application of gloss and matte lacquer caused a decrease in the printing density values and also the application of matte lacquer caused a decrease in the gloss values.

This article focuses on developing a methodology which can be used to estimate the concentration of dyestuff released from textiles during domestic laundering, so that further studies involving decolorization of the wastewater from domestic washing machine can be conducted in an attempt to develop eco-friendly domestic washing processes. Due to the complexity of the problem, an approach was adopted so that, as an initial step, synthetic red and blue reactive dye solutions were prepared as representative wastewater solutions using Reactive Red 195 and Reactive Blue 19 dyestuffs for the estimation of dye concentration. This was followed by an experimental work consisting of washing tests involving the calculation of dye concentration in the wastewater obtained from domestic washing machine as well as tergotometer as a machine simulator. For this part of the work, dyed cotton plain jersey fabric samples were used to obtain wastewater solutions. All the dye solutions and the wastewater samples were measured with VIS spectrophotometer, and the maximum absorbance values were obtained at relevant wavelengths. Although the characteristics of absorbance spectra of synthetic and wastewater solutions were very different, the maximum absorbance values of both solutions overlapped at relevant wavelengths. The concentration of the dyestuff was calculated from the absorbance values measured at 540 and 592 nm for the red and blue, respectively. The statistical analysis of the data suggested that tergotometer can be used as a domestic washing machine simulator. Moreover, the regression analysis done for the dyestuff concentration under discussion revealed that the most significant factor was the washing step (main wash or rinsing) (89.5%) followed by color (red or blue) (3.4%) and washing device (washing machine or tergotometer) (1.5%).

Methyl ester biodiesel was produced from Moringa Oleifera oil and Jatropha Curcas oil with the sole aim of assessing the feasibility of the feedstocks as viable sources of biodiesel in Botswana. Oil extraction and transesterification were carried out under identical experimental conditions for both Jatropha Curcas and Moringa Oleifera biomass. Oil was extracted from seeds through a soxhlet extraction method using the solvent, n-hexane. The extracted oil was then trans-esterified at 60 °C using a methanol/oil ratio of 12:1 at a stirring rate of 350 rpm, 3 wt. % catalyst loading and 120 min reaction time. Zinc Oxide modified with fly ash was used as heterogeneous catalyst for the process. GC analysis results of biodiesels produced indicated that the highest biodiesel yield was obtained from Jatropha seed oil. Moringa biodiesel showed a greater proportion of docosanedioic acid while Jatropha biodiesel composed of oleic acid in larger proportions. Both oleic and docosanedioic acid are unsaturated methyl esters. The results obtained suggests Jatropha as the more suitable feedstock as compared to Moringa.

Soluble polysaccharides were isolated from fruit pericarps of the Algerian Argania spinosa. The cell wall fraction was subjected to sequential extractions with H2O (2 × 2 h at 100°C), EDTA (1%, 6 h at 80°C) and KOH (1 and 4 M, 14 h at 25°C). The structures of the obtained polysaccharide fractions were characterized using gas chromatography (GC), infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The presence of arabinose, galactose and rhamnose in the pectin fractions suggests the presence of rhamnogalacturonan, while the abundance of xylose in the hemicellulosic fractions indicates the presence of xylan. The DSC data revealed the endothermal behavior of all the soluble polysaccharides and only two thermal transitions, the glass transition (Tg) and the fusion transition (Tf) have been recorded.

The paper deals with biogas yield production from two co-substrates - sorghum silage mixture of corn silage and crushed potatoes combined with mixture of livestock manure and swine slurry - in a semi-continuous digester under mesophilic conditions. This paper aims to evaluate the suitability of alternative substrates for biogas production under biogas plant operational conditions. In the first experiment, biogas yield was 0.159 Nm3 per hour with methane content of 56.96% vol. In the second experiment, biogas yield was 0.18 Nm3 per hour with methane content of 52.95% vol. Experiments confirmed that both substrates are suitable for biogas production under the given conditions.

The paper proposes a reagent method of water purification at the Kharkiv Coke Plant when using the phenolic wastewater in the water-circulating system, which corresponds to industry standards, together with coagulant (aluminum sulfate, aluminum hydroxychloride Pro-AQUA-18) and flocculant treatment (Extraflock and Besfloc). The use of cationic flocculants in water treatment has shown a high degree of efficiency in the removal of suspended substances compared with the Pro-AQUA-18 coagulant at a dose of 50 mg/dm3 or flocculant – 2-4 mg/dm3; it does not lead to the secondary pollution of the water and does not increase its corrosive activity. The purification of the clarified water was carried out using a filtration unit with a filtering load from a layer of quartz sand. The use of the proposed reagent method of water purification will allow it to be used for the technical purposes of the enterprise, reduce the consumption of fresh water, and eliminate the discharge of phenolic wastewater into the municipal sewer network.

Application of dried plant water soluble extracts in soil Pb decontamination is rear, but advantageous due to their ecological biodegradability. Single batch laboratory scale suitability of Terminalia mantaly, Panicum maximum, Eleusine indica and water as washing solutions for Pb removal from contaminated and spiked soils at different soil pulp densities (3%, 6%, 9%, 12%, 15% and 18%) and washing time (1, 3, 6, 12, 24 and 96 h) was investigated. Washings of Terminalia mantaly and Panicum maximum proved more efficient comparatively for contaminated soil with Pb removal efficiency of 27.2±0.64% and 27.0±0.52% respectively at 3% soil pulp density and washing time of 96 h. Removal efficiency increased with increasing washing time but decreased with increasing of soil pulp density. Furthermore, water was found effective for removing Pb from spiked soils with maximum removal efficiency of 74.5±3.38% at 3% soil pulp density after 1 h washing. High exchangeable fraction of Pb (81.2%) in spiked soil makes water more suitable against other washing solutions. Statistical t-testing showed significant difference in Pb removal efficiency between contaminated and spiked soils for all four washing solutions, reflecting differences in geochemical phases of Pb in both soils. Terminalia mantaly and Panicum maximum showed promising result in soil washing and have potential for application in Pb removal from contaminated soils. However, chemical modifications are needed to enhance and improve on their efficiencies. Similarly, more information is needed to predict and model removal efficiencies when multiple washing steps are applied.

Vinasse is the main by-product of ethanol production. In 2005, its application was regulated in the state of Sao Paulo, so if it is to be applied to the fields, its volume must meet the established concentration regulations. Straw contains one-third of sugarcane calorific value and can be used for cogeneration. For these purposes, the project objective was to assess the effects of straw on the concentration of vinasse solids through physical and chemical processes, so its concentrated form could be used as biomass for cogeneration. For that, different concentrations of straw, ferric sulphate, and ferric chloride were used. Turbidity reduction was the parameter analysed. Both reagents were effective in reducing the turbidity. The 200 ppm of ferric chloride and 0.25% straw content reduced the turbidity by 55.02% and 400 ppm of ferric sulphate and 0.25% of straw reduced it by 57.96%. The addition of straw showed no significant effect in terms of the turbidity reduction, however, both best treatments had 0.25% straw content addition in it. Straw can be used to concentrate vinasse, contributing to the efficiency of the process and increasing the energy potential of the concentrated solids.

Three-phase partitioning (TPP) was used to purify plant-esterase from wheat flour. Effect of various process parameters has been evaluated and plant-esterase was purified to 11.35-fold by optimized single step TPP system (50%, (w/v) (NH4)2SO4 saturation, 1:1 (v/v) ratio of crude extract: t-butanol at pH 4).The enzyme was found to be exclusively partitioned in the aqueous phase. Using TPP system, plant-esterase quickly purified to homogeneity with very high purity and activity. On the basis of single factor research, purification process was optimized by using response surface method, established a new type of high efficient purification plant-esterase method. To the best of our knowledge, this is the first report for purification and characterization of plant-esterase by using three phase partitioning (TPP). The results indicated that, TPP is a simple, quick, economical and very attractive process for purification of plant-esterase compared to conventional chromatographic protocols.

Sodium lignosulfonate (SL) was prepared from waste of cotton lignin (CL) through hydrothermal reaction method. Orthogonal experiment was designed with value of OIT as objective function. Polypropylene (PP) is a polymer produced by the addition polymerization of propylene. It is a white waxy material with a transparent and light appearance, which is widely used in food and pharmaceutical packaging. The results of GPC and TG analysis revealed that SL has stable thermal properties, which means that SL has the potential to be an antioxidant for PP materials. In addition, the scavenging effects of CL and SL were studied. The obtained results exhibited that the SL can obviously increase the scavenging effect on free radicals and it is a kind of new synthetic antioxidant with antioxidant property, which could effectively delay the oxidation of PP. Subsequent rheological experiments proved that the SL/PP sample can improve the heat-resistant oxygen performance of PP under the thermal oxygen shearing environment. Combined with the effect of SL on the mechanical properties of PP before aging, SL has a stabilizing effect on PP thermal oxygen aging.

The purpose of the presented research is to analyse possible methods of thickening of the Microcystis aeruginosa (Kützing) Kützing cyanobacteria using the obtained concentrate as a biomass for the production of energy carriers and biologically valuable substances. Method of cyanobacteria thickening under the action of electric current and in the electric field, as well as the method of coagulation–flocculation and gravity thickening, was experimentally investigated in labscale conditions. Electrical methods didn't show positive results for the Microcystis aeruginosa thickening, despite the reports of their potential efficiency in a number of previous studies. The high efficiency of the method of coagulation– flocculation and gravity thickening of Microcystis aeruginosa suspensions was obtained. The optimum concentrations of industrial polymeric coagulants and flocculants for the thickening of Microcystis aeruginosa suspensions were defined in the range of about 10 ppm for the coagulants and about 1 ppm for the flocculants. Negative effect of the previous cavitational treatment of the diluted suspensions of Microcystis aeruginosa on the effectiveness of the coagulation–flocculation and gravitational thickening was confirmed experimentally. Hydrodynamic cavitation should be recommended to use after the thickening as the next step of processing of concentrated suspensions of Microcystis aeruginosa to achieve maximum extraction of energy carriers and biologically valuable substances.

Excessive microalgal blooms can be caused by waste disposal into natural water bodies resulting in the destruction of aquatic life. However,, microalgae are also known to efficiently remediate pollutants. After the treatment of wastewater, microalgae absorb specific nutrients and can enhance the production of bioproducts. Growing microalgae as an alternative to wastewater treatment and bioproduct production has received considerable attention due to its rapid growth rate, efficient waste removal, tolerance to stress conditions and ability to accumulate valuable products. In addition, these microorganisms have a high photosynthetic rate of CO2 fixation, oxygen production and need no arable land for their cultivation. Nevertheless, in spite of these theoretical advantages, the issues surrounding the re-use of naturally existing microalgal strains need further exploration in respect to their isolation, identification and lab growth under stress conditions. The true potential of microalgae regarding wastewater treatment and energy has yet to be fully developed. The current cultivation system does not seem to be economically feasible as most of the strains used are commercially purchased. Indigenous microalgae could be the possible answer. Ammonia, one of the major constituents of most wastewaters, contributing to odor, taste, toxicity, and eutrophication is of utmost concern. The present review focuses on the growth of microalgae under high stress of ammonia in wastewater media. It also aims to present a clear-cut methodology for the isolation of microalgae from its indigenous habitat, its growth strategy under different trophic modes of nutrition, nutrient uptake, lipid, and fatty acid production. In addition, some solutions to the problem of how to make microalgae cost-effective and more sustainable are discussed in detail.

This paper is a kind of introduction to the special issue of CEER devoted to metal and composite structures. Papers collected in this issue were ordered from Authors who took part in International Conference on Metal Structures which was held in Zielona Góra in 2016. Selection of Authors and theme of ordered papers were done in cooperation with Metal Structures Section of the Civil Engineering Committee of the Polish Academy of Sciences. Selected papers included in this special issue of CEER were shortly presented in this editorial.

Precipitation methods are commonly used for removing phosphorus compounds from wastewater. Chemical precipitation method, based on adding iron, aluminium or calcium salts to the treated wastewater, is often used. Another possible way of precipitating phosphates is metal dissolution method, which is presented in this paper. The main difference between these two methods is how the phosphate precipitating ions are introduced to the wastewater. This paper discusses advantages and disadvantages of the metal dissolution method in comparison with traditional precipitation methods. Differences in the secondary contamination of treated wastewater by iron ions, conductivity, total alkalinity and pH correction process; the use of recyclable wastes; and energy consumption are discussed.

The aim of the paper was to determine the effectiveness of the removal of 4, 5and 6 - ring PAHs from coking wastewater using sodium percarbonate Na2CO3∙1,5 H2O2 and iron sulphate in acid condition. The samples were exposing to ultraviolet rays. The source of UV-C radiation was a lamp emitting a wave of light with a length of λ = 264 nm, placed directly above the layer of the samples wastewater. The sodium percarbonate Na2CO3 1.5 H2O2 doses were determined on the basis of stoichiometric calculation. Ratio of iron ions to the hydrogen peroxide released in reaction was: 0.5; 0.4; 0.3; 0.2; 0.1. Before and after the oxidation process, COD and TOC value were determined and as well as concentrations of selected PAHs. The total concentration of tested PAHs before oxidation reached the value of 995 μg/L. The average content of organic pollutants determined by the chemical oxygen demand (COD) was 538 mg/L, while the average content of Total organic carbon (TOC) was 180 mg/L. The use of sodium percarbonate caused the oxidation of organic pollutants and lowering of COD and TOC in the following ranges: 22-46% and 10-30%. For individual PAHs the degradation efficiency was in the ranged from 95% to 99.9%. The degradation efficiency of 4 ring hydrocarbons caused 98% and 5 and 6 ring of hydrocarbons was 98.7% and 99.4%, respectively.

The paper presents the results of the research about the efficiency of organic substance removal in a hybrid sand filter. The investigations were carried out on a model wastewater treatment plant consisting of a preliminary sedimentation tank and two sand filter with a horizontal flow of wastewater (aerobic and anaerobic beds). The efficiency of BOD5 and COD removal was analysed for different wastewater hydraulic load levels: 0.72; 1.08; 1.44 dm3·d−1. The best efficiency of BOD5 and COD removal was obtained when the hydraulic load level was 1.08 dm3·d−1, respectively 83.8 and 72.3%. The average values of BOD5 and COD in the treated wastewater were significantly higher than the values deemed acceptable by relevant regulations in Poland. Based on the studies in the analyzed case, it was found that, sand filters with horizontal flow, do not guarantee high effluent treatment effect of typical household wastewater. In order to obtain a better efficiency of organic substance removal in a hybrid sand filter wastewater need to be oxygenate before being carried to these systems.

In the bioethanol industry, per liter of the produced alcohol 9 to 14 liters of vinasse are obtained as a byproduct. If the vinasse is directly shed into bodies of water without an adequate treatment, it may have negative effects on the existing biota and human health due to its high turbidity and color, low pH and high content of organic material. The purpose of this study was to assess the acute toxicity of vinasse by means of a rapid test with Aliivibrio fischeri and compare it with a standard immobilization assay with Daphnia magna. The standard assay of D. magna by means of its EC50 of 4.7% showed that organism was more sensitive to the contaminant, in comparison with the 69.6% obtained with the A. fischeri which suggests that it should be continuesly used as one of the organisms of first choice for the evaluation of the acute toxicity of this effluent.

Single cell oil (SCO) is an attractive alternative source of oil, which, depending on the fatty acid composition, can be used as a feedstock for biodiesel production, as an ingredient for pharmaceuticals or as a source of essential fatty acids for human and animal consumption. However, the use of SCO is limited due to use of relatively expensive food or feed products in the cultivation of SCO producing microorganisms. In order to reduce SCO production costs, the use of cheaper feedstock such as biodegradable agro-industrial wastes are necessary. At the same time, the microbial treatment of biodegradable wastes ensures the neutralization of environmentally harmful compounds and reduces the negative impact on the environment. Oleaginous microorganisms are capable of fermenting a variety of industrial by-products, waste products and wastewaters, however further discussion on properties of the waste materials is necessary to facilitate the selection of the most appropriate waste materials for SCO production. Thus, this review compares various industrial waste products that can be used as cheap feedstock for the cultivation of SCO producing microorganisms. Industrial waste products, by-products and wastewaters are compared according to their global availability, current use in competing industries, required pre-fermentation treatments, oleaginous microorganism cell concentrations and SCO yields.

Various article which indicating the Aerobic granular sludge (AGS) instability, particularly in prolonged phase operating duration become a significant obstacle to its implementation. Generally, prolonged the operation period will lost its stability that can degrade performance effectiveness. As AGS stabilization in hydrodynamic shear force and resisting mass transfer resistance within the reactor generally defined or evaluated by microbial community, bioactivity, extracellular polymeric substance (EPS) structure and granular aspect. The aim of this research in order to illustrate the EPS formation on AGS which is preserved at 4°C in sequencing batch reactor (SBR) by sewage for eight months. The effective of granulation method and redevelopment of AGS stability by particular pressure produced with several hydrodynamic shear force and mass transfer resistance which controlled by low organic loading rate (OLR) between 0.26 and 0.81 kg CODs/m3 d with 1.33 cm/s of superficial air velocity (SAV). The confocal laser scanning microscope (CLSM), Fourier transform infrared (FTIR), and energy dispersive X-ray spectrometer (EDX) were implemented to notice the evolution in composition of EPS that revealed the intermolecular interaction helped the aerobic granule stability as seed to achieved the performance of EPS on stability of AGS.

Acute toxicity of raw and treated greywater towards Daphnia magna was assessed in this study. Treatment was performed with exposure of greywater to the fly-lime mixture After 48 h of exposure, 100 % mortality of D. magna was recorded when testing the following volumetric fractions of the raw greywater streams in the tested liquid medium (%; v/v): 10 % for kitchen greywater, 5 – 10 % for bathroom greywater and 1.25 – 10 % for laundry greywater. After greywater treatment with the fly-ash-lime mixture with pH adjustment to 7.0, 80 % of neonates of D. magna survived after exposure to treated laundry greywater in all dilutions at 48 h. At the same time, 100 % of neonates survived exposure to treated bathroom and kitchen greywater at all volumetric fractions. Therefore greywater had acute toxicity to D. magna, i.e. greywater treatment was required before its discharge or reuse. Values of the Pearson’s correlation coefficient between the chemical components of the raw greywater and treated greywater and the survival of D. magna indicated a lack of statistically significant correlation at 5 % level of significance (p-value > 0.05 in all cases), i.e. the survival of D. magna was independent of the concentration of chemical constituents in greywater samples tested. Further studies will have to be conducted on the chronic toxicity of the greywater effluent after treatment with the fly-lime mixture. Experiments from this study will have to be re-run for the fully scaled-up version of the fly-lime mixture-based greywater treatment systems.

This study aims at investigating the potential of Acacia gerrardii pod for the removal of Cr(VI) in batch system. Effect of solution pH, biosorbent dosage, initial concentration of Cr(VI), contact time on the removal process was examined. Complete removal of hexavalent chromium was achieved at pH values 1.0 and 2.0 whereas maximum removal of total chromium was obtained at pH of 3.0. The study showed that the biosorption and bioreduction mechanisms were involved in the removal process. The time required for complete removal of Cr(VI) using the pod of Acacia gerrardii was shortened with an increase in biomaterial dosage and decrease in Cr(VI) concentration. Kinetic data was well described using Park kinetic model. Freundlich isotherm model adequately fitted the equilibrium data indication multilayer adsorption of total chromium on the surface of biomaterial. The pod of Acacia gerrardii could be used efficiently for the removal of hexavalent chromium from aqueous solutions.

Some new Ostrowski’s inequalities for functions whose n-th derivatives are h-convex are established.

EU Directive of MARPOL Annex VI and its economic impact on the Nordic paper industry is theme of this research work. Empirical data for analysis purposes was gained from a large Nordic paper mill that exports bulk products mainly to Europe (70 % of its volume). The study shows that in the end the industry’s location still has an economical effect, and that the location has a distinct impact on competition through rising transportation costs. Environmental regulation continues and fosters long-term upwards trajectory of transportation cost, which has been experienced by the paper mill earlier during years 2001-2009. Sulphur regulation change to cleaner grades of maritime diesel did not turn as heavy cost increase in the 2015, however, possibility to gain cost benefits in rapidly deteriorating oil markets were not reached either. Therefore, in depressed industrial product markets, like paper industry, implications were such that margins of export industry remained low.

The municipal sludge characterized non-Newtonian behaviour, therefore the viscosity of the sewage sludge is not a constant value. The laboratory investigation was made using coaxial cylinder with rotating torque and gravimetric concentration of the investigated sludge ranged from 4.40% to 2.09%. This paper presents the investigation on the effect of concentration of rheological sludge behaviour. The three different rheological models: Bingham (plastic model), Ostwald-de Waele (power-law), Hershel-Bulkley’s were calculated by fitting the experimental data of shear stress as a function of shear rate to these models. In this study, the 3-parameter Herschel- Bulkley’s model fits the experimental data best.

The process of aerobic stabilization of sludge is a process used in small or medium sewage treatment plants (up to 15 000 ENI). Owing to its energy intensity resulting from the need for intensive sedimentation and longterm process, many researches are being conducted on its intensification. One such method is disintegration. The purpose of disintegration is to increase the susceptibility of sewage sludge to aerobic decomposition by breaking up sediment flocs into fine particles along with the breakdown of cell membranes and then allowing biodegradation. The paper presents results of research of aerobic stabilized sludge, which is a mixture of non-disintegrated and microwave disintegrated sludge in different volume proportions. It was shown that sludge stabilized more quickly during the first days of the process. The minimum reduction of organic solids required at 38% for stabilized sludge occure earlier in mixed sludge tests than in non-disintegrated sludge.

The aim of this work was to develop the method of lactic acid (LA) separation from fermented whey. CMI-7000 Cation Exchange Membrane and AMI-7001 Anion Exchange Membrane were employed in electrodialysis process. Experiments showed that the selected membranes separated organic acids effectively (including LA) from other organic ingredients present in medium. Selecting an appropriate volume of a receiving chamber could lead to LA concentration. Moreover, membrane fouling during separation was investigated. This phenomenon is negligible which is the main advantage of this process. As it was shown during batch processes, with the voltage increase, the rate of electrodialysis increases as well. It prompts to a reduction of residence time in electrodialyzer during a continuous separation.

Systems of anaerobic digestion should be used for processing of organic waste. Managing the process of anaerobic recycling of organic waste requires reliable predicting of biogas production. Development of mathematical model of process of organic waste digestion allows determining the rate of biogas output at the two-stage process of anaerobic digestion considering the first stage. Verification of Konto’s model, based on the studied anaerobic processing of organic waste, is implemented. The dependencies of biogas output and its rate from time are set and may be used to predict the process of anaerobic processing of organic waste.

Sludge conditioning is an important stage in sludge management. In the present study, a sequence of freeze/thaw-electro-Fenton process was designed and specific resistance filtration (SRF) was monitored during sludge conditioning as an important factor in sludge dewaterability. Furthermore, protein and polysaccharide concentrations were measured during the experiments. Results showed that the lowest SRF value contributed to −10°C in freezing process which showed a reducing trend by decreasing solution pH. In addition, results revealed that solution pH less than 3 caused a significant improvement in sludge dewatering; so the lowest SRF has been registered at pH = 2. By increasing current intensity from 0.5 to 1A, SRF values were reduced and then followed by an enhancement with increasing current intensity to 3.2 A. The lowest SRF value (6.1 × 104 m/kg) was obtained at H2O2 = 30 mg/L which was the best conditions for sludge dewatering.

The article deals with the effects made by using various n-butanol-diesel fuel blends on the combustion history, engine performance and exhaust emissions of a turbocharged four-stroke, four-cylinder, CRDI 1154HP (85 kW) diesel engine. At first, load characteristics were taken when running an engine with normal diesel fuel (DF) to have ‘baseline’ parameters at the two ranges of speed of 1800 and 2500 rpm. Four a fossil diesel (class 1) and normal butanol (n-butanol) fuel blends possessing 1 wt%, 2 wt%, 3 wt%, and 4 wt% (by mass) of n-butanol-bound oxygen fractions were prepared by pouring 4.65 wt% (BD1), 9.30 wt% (BD2), 13.95 wt% (BD3), and 18.65 wt% (BD4) n-butanol to diesel fuel. Then, load characteristics were taken when an engine with n-butanol-oxygenated fuel blends at the same speeds. Analysis of the changes occurred in the autoignition delay, combustion history, the cycle-to-cycle variation, engine efficiency, smoke, and exhaust emissions NOx, CO, THC obtained with purposely designed fuel blends was performed on comparative bases with the corresponding values measured with ‘baseline’ diesel fuel to reveal the potential developing trends.

With the increasing population and rise in industrialization, the demand for petroleum reserves is increasing almost daily. This is causing depletion of the non-renewable energy resources. This work aims to find an alternative fuel for diesel engines. The use of poultry litter oil biodiesel obtained from poultry industry waste, which is a non-edible source for biodiesel, is very encouraging as an alternative fuel for diesel engines. The aim of this study is to observe and maximize the performance of poultry litter oil biodiesel by adding alumina nanoparticles and ethanol. The biodiesel is prepared with acid and the base catalysed transesterification of poultry litter oil with methanol using concentrated sulphuric acid and potassium hydroxide as catalysts. The experimentation is carried out on a CI engine with three different blends - B20 biodiesel blend, B20 biodiesel blend with 30 mg/L alumina nanoparticles, and B20 biodiesel blend with 30 mg/L alumina nanoparticles and 15 ml/L ethanol. The performance, combustion and emission characteristics of all three blends are compared with neat diesel. The results of the experiment show that ethanol as an additive improves the combustion and performance characteristics. It increases the brake thermal efficiency and peak cylinder pressure. It also reduces CO and UBHC emissions and there is a marginal increase in NOxemissions as compared to neat diesel.

The article presents research results of the introduction of powdery activated carbon to the existing technological system of the groundwater treatment stations in a laboratory, pilot plant and technical scale. The aim of the research was to reduce the content of organic compounds found in the treated water, which create toxic organic chlorine compounds (THM) after disinfection with chlorine. Nine types of powdery active carbons were tested in laboratory scale. The top two were selected for further study. Pilot plant scale research was carried out for the filter model using CWZ-30 and Norit Sa Super carbon. Reduction of the organic matter in relation to the existing content in the treated water reached about 30%. Research in technical scale using CWZ-30 carbon showed a lesser efficiency with respect to laboratory and pilot-plant scale studies. The organic matter decreased by 15%. Since filtration is the last process before the individual disinfection, an alternative solution is proposed, i.e. the second stage of filtration with a granular activated carbon bed, operating in combined sorption and biodegradation processes. The results of tests carried out in pilot scale were fully satisfactory with the effectiveness of 70–100%.

Pattern recognition method (PRM) was applied to gas chromatographic (GC) data for a fatty acid methyl esters (FAME) composition of commercial and laboratory synthesized biodiesel fuels from vegetable oils including sunflower, rapeseed, corn and palm oils. Two GC quantitative methods to calculate individual fames were compared: Area % and internal standard. The both methods were applied for analysis of two certified reference materials. The statistical processing of the obtained results demonstrates the accuracy and precision of the two methods and allows them to be compared. For further chemometric investigations of biodiesel fuels by their FAME-profiles any of those methods can be used. PRM results of FAME profiles of samples from different vegetable oils show a successful recognition of biodiesels according to the feedstock. The information obtained can be used for selection of feedstock to produce biodiesels with certain properties, for assessing their interchangeability, for fuel spillage and remedial actions in the environment.

The introductory part of the paper is devoted to the classification of aggregates according to various criteria, one of them is the geographical origin of aggregates. From the point of view of the circular economy, the use of recycled aggregates comes to the fore, mainly from the ecological point of view but also from the economic point of view. The paper summarizes the results of research focused on the variation of the amount of 2 Recycled concrete aggregate fractions in concrete, followed by an evaluation of the effect of the presence of recycled material in the mixture on the selected property, specifically compressive strength. The highest compressive strength 34.7 MPa after 28 days hardening reached sample containing 100% recycled fraction 4/8 mm, and 60% recycled fraction 8/16 mm. This value is only slightly different from the compressive strength of the reference sample (34.4 MPa).

Aim of the paper is to analyse specific factors of human-robot collaboration and adoption to Industry 4.0 technologies in relation to working in mixed teams and in virtual work environment. Based on literature review and current findings in unified theory of technology acceptance and use of technology (UTAUT) model and its extensions, new endogenous factors might be included/considered, in a UTAUT model, namely emotional attitude (trust towards technology, perceived threat) and new moderators such as a location of organization and type of workplace-based training in organization. Team identification and self-extension process are intended as drivers for development of positive attitudes in human-robot collaboration and prerequisites of sustainable human-robot interaction. Regarding the findings in human-robot collaboration, the authors suggest including the type of personality and the attitudes towards Human-Robot collaboration among the extended factors of technology adoption within Industry 4.0 strategy. Emotional attachment acts as a relevant factor of successful Human-Robot collaboration that can be maintained by a support of team identification and self-extension process. For the development of positive attitudes in human-robot collaboration, principles of personalized design can be applied, e. g. engaging the workers in designing specific features of the robot. It can be supposed that specific models of technology adoption - as UTAUT/UTAUT2 will require new extensions in a context of work analysis in a virtual work environment, e.g. health and psychological assumptionsIn the paper, subjective assessment of the increase in well-being of the workers after the adoption of Industry 4.0 technologies is identified as one of the new Industry 4.0 outcomes within the human capital definition of Industry 4.0.

Corporate culture is made by the company´s employees. However, their age composition is different and is members of different generations that interact. Every generation brings with it something new, not only positive but also negative. Therefore, each generation should work together to eliminate the negative aspects and highlight the benefits of each generation and exploit them to their advantage. Each of the generations influences the corporate culture in different ways. The aim of the paper is to point out the results of research, which was realized at Faculty of Materials Science and Technology in Trnava and focused on individual generations of employees. We draw attention especially to the Generation Z, its impact on corporate culture and the new “wind” that it brings. This paper was written on the basis of research results of VEGA project No.1/0348/17 “The impact of the coexistence of different generations of employees on the sustainable performance of organisations”.

This paper focuses on the characteristics of the main challenges posed by the changes in demographic composition of labour market and requisite to adjust motivational programs to expectations of employees in industrial enterprises in Slovakia, but also to develop strategies to manage the cooperation between different generations. The paper describes the situation in Slovakia based on the analysis of data from quantitative research collected in 2018 on a sample of 534 employees in industrial enterprises. The empirical findings presented, which describe the differences between generations, focus mainly on the importance of work motivation factors and the level of achievement of these factors in correlation with the stated intention to change employment. Analysed data confirmed that relationships with colleagues are generally the most important work factor for all generations, but we found some significant differences between generations in work motivation items such as career advancement, personal growth, achievement, advantageous working hours and benefit to society.

Deep learning is a kind of machine learning, and machine learning is a kind of artificial intelligence. Machine learning depicts groups of various technologies, and deep learning is one of them. The use of deep learning is an integral part of the current data classification practice in today’s world. This paper introduces the possibilities of classification using convolutional networks. Experiments focused on audio and video data show different approaches to data classification. Most experiments use the well-known pre-trained AlexNet network with various pre-processing types of input data. However, there are also comparisons of other neural network architectures, and we also show the results of training on small and larger datasets. The paper comprises description of eight different kinds of experiments. Several training sessions were conducted in each experiment with different aspects that were monitored. The focus was put on the effect of batch size on the accuracy of deep learning, including many other parameters that affect deep learning [1].

In the changing economic environment, global competition where the customer demands are changing continuously, the enterprises have to focus on cost reduction, efficiency improvement, higher productivity and profitability. In the production, the resources (raw materials, humans, machines, equipment, etc.) are always limited. It is very important for the manufacturing companies to produce cost effective final products in a short lead time which can be achieved by minimized cost and higher effectiveness, and therefore, efficiency improving methods are needed. There are lot of tools and sophisticated methods for design, analysis and improvement of production and logistical processes. The author introduces the most often applied methods for it, which are the simulation, Lean method and layout design. The paper summarizes the characteristics, typical application fields of these methods and the reasons for application of these. Main aims of logistics process improvement and the main steps and advantages of the described methods are introduced.

Nowadays, the environmental assessment becomes more and more of interest as an additional tool for the decision-makers. The researchers in civil engineering focus on building materials, structures as well as whole buildings environmental evaluation. Analysis of the environmental impact of particular structures may be helpful for selecting building materials, with regard to the environmental performance of buildings in the early project phase. The aim of this paper is presentation of an environmental evaluation of the rarely assessed particular structures – building foundations and the analysis of the share of the building foundations to the overall environmental impact of building as well. The obtained data point to the need to include the environmental impacts of foundations when assessing the buildings, because of it is a necessary part of any type of family house. One kilogram of built-in foundations materials was responsible for emissions of 0.092 kg of greenhouse gases expressed by carbon dioxide (CO2). Embodied energy was calculated as equal to 1.14 MJ per 1kg of foundations materials and 832.2 MJ/m2 per building floor area. The foundation materials of houses contributed to the total environmental impact of the whole buildings by, on average, 15.0 and 22.8 % for embodied energy and global warming potential, respectively.