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Open access

Liliana Cepoi, Inga Zinicovscaia, Tatiana Chiriac, Liudmila Rudi, Nikita Yushin and Vera Miscu

Abstract

In order to assess ability of Spirulina platensis to recover silver and gold ions from the environment the bioaccumulation of silver and gold ions and their effect on growth, proteins and carbohydrates content of Spirulina platensis biomass was studied. Silver nitrate (AgNO3) in concentration range 0.01-1 mg/dm3 and tetrachloroaurate Na[AuCl4] in concentration range 18.5-370 mg/dm3 were added as component of the Spirulina platensis cultivation medium. In case of silver two cultivation media were studied: standard and Cl-free. The process of silver and gold uptake was traced using neutron activation analysis. Presence of silver ions in standard cultivation medium reduced biomass productivity by 66 %, while in Cl-free biomass productivity was reduced by 11.8 % only. The reduction of proteins content by 30 % in Cl-free medium and by 19 % in standard medium was also observed. The experiments showed that in case of gold ions loading, the biomass productivity and protein content were reduced only at high Na[AuCl4] concentration in the medium. The behaviour of carbohydrates content change was similar under silver and gold loadings: decrease at low metal concentration followed by increase at high metal concentrations. Scanning electron microscopy allowed observation of spherical metal nanoparticles, which were formed extracellularly during silver and gold bioaccumulation. Spirulina platensis can be used for recovery of precious metals as well as metal nanoparticles production.

Open access

Krzysztof Gondek, Monika Mierzwa-Hersztek, Michał Kopeć, Jakub Sikora, Tomáš Lošák and Piotr Grzybowski

Abstract

In the course of analysing sewage sludge biochar (BC) as a material containing phosphorus loads, we determined the following: effect of thermal conversion of three different sewage sludge biochars on the content and availability of P in biochars (BC-1, BC-2 BC-3), effect of their application on selected forms of P in soil and on the accumulation of this component in Poa pratensis L. biomass. Regardless of the type of BC, the contents of P-H2O and P-CaCl2 were lower than the contents determined in unconverted sewage sludge. A significant increase in the content of P-CaCl2 compared to the control was noted in the soil of treatments where 1 and 2 % additions of BC-2 and BC-3 were applied. Soil pH (r = 0.826; p ≤ 0.05) and the content of Ca-exchangeable (r = 0.712; p ≤ 0.05) had the strongest effect on the content of P-CaCl2 in soil; however, no significant relationship was found between the amount of P-introduced with BC, the contents of Al-ox., Fe-ox. and the content of P-CaCl2. Significant (p ≤ 0.05) increase in the phosphorus content in plant biomass was noted in all treatments compared to the control. Regardless of the type of biochar applied, the highest amount of P-uptake was determined in treatments where the greatest addition of BC (2 %) was introduced into the soil. A significant relationship between P-uptake and the amount of P-introduced with BC into the soil (r = 0.726; p ≤ 0.05) was demonstrated.

Open access

Junshan Lei, Jiazhou Chen and Wei Yin

Abstract

To investigate the retention efficiency and mechanism of nitrogen of Vegetative filter strips (VFSs) in the Danjiangkou Reservoir area, simulated runoff discharging experiments were carried out in a new-established Bermuda VFS. The results showed that the Bermuda VFS reduced 73.1-86.1 % of surface runoff through infiltration. The outflow rate of runoff increased first and then became stable with time. The concentration reduction rates (CRRs) and load reduction rates (LRRs) of NH3-N increased initially and then decreased with the increase of inflow concentration. The average CRRs and LRRs of NH3-N in three treatments ranged 66.1-90.3 % and 90.0-96.7 %, respectively. The concentration reduction of NH3-N was primarily achieved by soil adsorption. The optimal inflow concentration of NH3-N for the optimum CRR was between 0.65 and 3.52 mg/dm3. The CRRs and LRRs of NO3-N fluctuated between 6.8-14.0 % and 72.0-77.9 % in three treatments. The concentration reduction of NO3-N was primarily achieved by plant uptake and soil microbe assimilation. The optimal inflow concentration of NO3-N for optimum CRR exceeded 6.78 mg/dm3. The CRRs and LRRs of TN increased with the increase of inflow concentrations. The average CRRs in the low, moderate and high treatments reached 9.7, 14.8 and 27.4 %, respectively, and the average LRRs reached 72.1, 74.3 and 81.2 %, respectively. The optimal inflow concentration of TN for optimum CRR exceeded 10.21 mg/dm3. The study showed that Bermuda grass can retain nitrogen in runoff efficiently and should be promoted around the Danjiangkou reservoir.

Open access

Marta Marszałek, Zygmunt Kowalski and Agnieszka Makara

Abstract

Pig slurry is a heterogeneous mixture of faeces, urine, undigested remains of feed items and water used for flushing of animal excrement and to maintain the proper hygiene of livestock housing. It is formed on farms which use the non-bedding system of pig breeding i.e. animals are kept on the partially or fully slatted floors. According to the Polish law pig slurry is defined as a liquid natural fertilizer intended for agricultural use. The storage and application of pig slurry on arable land affect the surroundings and may create a number of serious risks related to, among others, the pollution of water-soil environment with biogenic elements, heavy metals, pathogens and pharmaceuticals. The article presents the reasons for the occurrence of excessive amounts of nitrogen, phosphorus, copper, zinc and antibiotics in pig slurry. The possibility of microbial and pharmaceutical contamination of water, soil and plants as well as their pollution with biogens and heavy metals as a result of improper storage and excessive spreading of pig slurry have been characterized. Moreover, methods of preventing the above-mentioned threats with reference to Polish and EU legal acts have been discussed.

Open access

Gaweł Sołowski, Izabela Konkol and Adam Cenian

Abstract

A model for calculating the maximal theoretical production of hydrogen from corn wastes is proposed. The model has been used to estimate the potential for hydrogen production from cereals wastes such as wheat, barley, and corn which are cultivated in Poland. The potentials for Pomorze and other regions of Poland are compared. The hydrogen produced from cereal wastes in Poland could potentially meet 47 % of national hydrogen demand.

Open access

Larisa Sabliy, Yevgeniy Kuzminskiy, Veronika Zhukova, Marina Kozar and Henryk Sobczuk

Abstract

The article presents the developed anaerobic-aerobic wastewater treatment technologies. These technologies aimed at removing the organic matter, nitrogen and phosphorus by means of microorganisms immobilized on fibrous carrier surfaces. The results of the laboratory research show the high efficiency of milk wastewater treatment. The following degrees of reduction were achieved for the pollutant indicators: COD -86.7-93 %, total nitrogen - 96.9-97.9 %. Compared to the traditional treatment technologies applied in Ukraine, these values are high. The concentration of organic matters and biomass of not attached bacteria decreased in bioreactor chambers. When the purification process ends, a small amount of excess biomass remains; therefore, its self-oxidation and self-regulation occurs as a result of consumption by the organisms occupying higher levels of trophic chains. The use of anaerobic-aerobic bioreactors system for the treatment of wastewater enables achieving high outflow quality and prevents the suspended substances from slipping. Immobilization of microorganisms on the first stage of the technology prevents the formation of big amount of excessive sludge and removes biomass from the bioreactor, which allows the technology even for the heavily polluted wastewater. In reactors containing immobilized microorganisms, the organic matter compounds used in subsequent reactors for phosphate accumulation are split. The presented biotechnology saves electric energy, provides sufficient quality of treatment, and ensure the compliance of treated wastewater with the effluent standards.

Open access

Joanna Zembrzuska, Dobrochna Ginter-Kramarczyk, Anna Zając, Izabela Kruszelnicka, Michał Michałkiewicz, Zbysław Dymaczewski, Anna Piątkowska and Magdalena Wawrzyniak

Abstract

The article presents results regarding the ibuprofen reduction rate at three various temperature values (8, 18 and 28 °C) which were conducted using a static test in accordance with the PN-C-04645 ‘Water and wastewater. Evaluation of partial biodegradation of anionic and non-ionic surface active substances. Initial test’ standard. A single study cycle including the analysis of ibuprofen degradation rate in specific temperature variants lasted 24 h. The activated sludge for tests was obtained from the aeration zone of a bioreactor localized in the Central Wastewater Treatment Plant in Poznan City (Poland), which was used for inoculation (1 g/dm3) of sterile samples with the medium and ibuprofen (10 mg/dm3) after appropriate pre-treatment (intense aeration for 5 h). The analysis procedure included the separation and concentration of analytes from biodegradation samples by means of solid phase extraction (SPE) and subsequent determination with high performance liquid chromatography coupled with mass spectrometry (LC-MS/MS) using an UltiMate 3000 RSLC liquid chromatogram (Dionex, USA) with a tandem API 4000 QTRAP mass spectrometer (Biosystem, MDS Sciex, USA). Both literature review as well as the conducted initial studies confirmed that the removal of ibuprofen proceeds more rapidly at higher temperature values. A higher retention rate also enhanced the reduction of ibuprofen concentration. A decrease of its concentration was observed after 24 h, which reached 40 and 50 % for temperature values of 8 and 18 °C, accordingly, whereas the highest reduction by approx. 65 % was noted at 28 °C.

Open access

Joanna Kapusta-Duch, Teresa Leszczyńska, Barbara Borczak, Adam Florkiewicz and Anna Ambroszczyk

Abstract

Broccoli has a very good nutritive value, high antioxidant activity and pro-healthy potential. Freezing is one of best methods for vegetable storage and broccoli belongs to the group of vegetables subjected to this process on an industrial scale. This work investigates the effect of type of container: low density polyethylene (PE-LD) bags and oriented polystyrene (OPS) boxes on selected quality parameters in frozen broccoli. The experimental material was the broccoli cultivar Lord F1. The vegetable was subjected to blanching, freezing and 3-month storage. At the every stage of an experiment the material was examined in terms of: vitamin C content; β-carotene; total polyphenols; and antioxidant potential, which was determined basing on the ability to quench the ABTS˙ + free radical. It has been found that vegetables which were kept frozen for 3 months in two types of container had parallel levels of vitamin C, β-carotene; total polyphenols; and similar antioxidative potential.

Open access

Antonina Kalinichenko and Valerii Havrysh

Abstract

In the world there are two main problems concerning energy and ecology. Despite the crude oil price fluctuation, it has tended to increase. Moreover fossil fuel burning emits hazard compounds, including greenhouse gas. To solve them alternative fuels for vehicle have to be used. In due to properties, their usage impacts on the engine efficiency. The alternative fuel usage needs additional investment costs on the vehicle engines adaptation and fuel supply infrastructure. So, decisions must be based on mathematical apparatus. Three submodels were used in the suggested mathematical model: energy and economic indicator for fuels; energy and economic indicator for vehicles; criteria for investment projects. As a criterion of investment projects the profitability index has been grounded. The mathematical model and the algorithm for determining the feasibility of the alternative fuel utilization have been developed. The proposed algorithm includes the following stages: calculation of the fuel energy cost; calculation of the criteria for vehicles; determining the maximum value of investments; making decisions. Biofuels and gaseous fuels for some countries have been studied. The economic attractiveness of the alternative transport fuels has been presented. According to mathematical modeling, gaseous fuels are more economically attractive compared with liquid biofuels. Among gaseous fuels, LPG has a higher economic efficiency. The economic margin of alternative fuel application feasibility has been determined.

Open access

Shahryar Jafarinejad

Abstract

The performance and economic simulation and modeling are crucial for accurate and rapid designing, construction, and forecasting future economic needs of municipal wastewater treatment plants (MWWTPs). In this study, combined nitrifying trickling filter/activated sludge (NTF/AS) process was suggested for the modernization of a MWWTP and the performance and economics of MWWTPs based on the combined TF/AS process and combined NTF/AS process were analyzed and compared. In real, the performance, total project construction, total operation labor, total maintenance labor, total material, total chemical, total energy, and total amortization costs of these proposed MWWTPs were calculated and compared. Under the used design criteria and operational conditions in this study, the project construction cost of the MWWTP based on TF/AS was 15.25 % higher than that of the MWWTP based on NTF/AS. Also, MWWTP based on NTF/AS was cost effective and the material and amortization costs for both plants were higher in comparison with the operation, maintenance, energy, and chemical costs. It is necessary to note that this study is a computer simulation for a case and drawing general conclusions only on the basis of this simulation may be insufficient.