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Progress in Agricultural Engineering Sciences
Authors: Cecilia Hodúr, Szabolcs Kertész, József Csanádi, Gábor Szabó, and Zsuzsanna László

In this study the performance of a vibratory shear-enhanced processing system (VSEP) for the concentration of cheese whey was assessed and compared with a classical, cross-flow, plate and frame membrane configuration system (3DTA) with the same membrane (i.e. a C30F UF regenerated cellulose UF membrane with a 30 kDa molecular weight cutoff). The temperature and pressure dependences of the permeate flux, the permeate flux reduction ratio, the resistances and the rejection values were investigated. Comparison of the two systems revealed a definite advantage for the VSEP system equipped with the same membrane and operated at the same pressure and temperature. The VSEP system yielded a permeate protein retention of 99.7% vs. 74.5% for the 3DTA system, together with a higher average flux: 54 L m −2 h −1 vs. 44.2 L m −2 h −1 . The flux reduction ratio ( J/J 0 ) was 0.60 vs. 0.42, and the total resistances 2.87*10 +13 m −1 vs. 4.54*10 +13 m −1 for the VSEP and 3DTA system, respectively.

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A nyíregyházi búzaszalmával komposztált szennyvíziszap, a debreceni anaerob módon rothasztott szennyvíziszap és a miskolci riolittufával és karbidmésszel érlelt, granulált szennyvíziszap talajmikrobiológiai hatásait tanulmányoztuk tenyészedé-nyes kísérletben. Kezeletlen barna erdőtalajon (kontroll 0%), valamint a szennyvíziszapokat kezelésenként 10, illetve 15%-ban tartalmazó talajkultúrákban takarmányborsó jelzőnövényeket neveltünk. Megállapítottuk, hogy a talaj szennyvíziszapokkal való kezelése és a talaj-mikroorganizmusok száma és tevékenysége között szoros összefüggés van. Mindhárom iszap esetében valamennyi mintavételi időpontban a kontrollhoz képest megemelkedtek, vagy szignifikánsan nem csökkentek az összes baktériumszám és a mikroszkopikus gombaszám értékei. Az iszapok fokozták az ureáz, a dehidrogenáz és a celluláz enzim aktivitását, míg a foszfatázaktivitás lényeges változást nem mutatott. Ezeket a kedvező hatásokat feltételezésünk szerint a szennyvíziszapokkal bekerült, a mikrobák szaporodását és enzimtevékenységét stimuláló anyagoknak lehet tulajdonítani. A kísérletben alkalmazott különbözőképpen előkezelt települési szennyvízisza-pok mikrobaszámra és enzimaktivitásra gyakorolt hatását összehasonlítva, mindhárom esetben egyértelműen pozitív, de egymástól kissé eltérő eredményeket kaptunk. A vizsgált iszapok közül a debreceni rothasztott és víztelenített iszap hatása kifejezetten kedvező volt. A nyíregyházi rothasztás után komposztált iszap, valamint a miskolci granulált, illetve ásványi anyagokkal kevert és érlelt iszap jótékony hatása kisebb mértékű volt és közöttük lényeges különbséget nem találtunk. Az anaerob rothasztás, mint iszapstabilizációs eljárás hatásos előkezelésnek bizonyult, de mind-három iszapkezelés hozzájárulhat az eredményesebb végső elhelyezéshez. A vizsgált települési szennyvíziszapok szakszerű mezőgazdasági alkalmazásuk esetén pozitív hatást gyakorolhatnak a talajbiológiai életre, amely lényeges a talaj anyagforgalmi dinamikájának javításában, a talaj termékenységének fokozásában.

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Agrokémia és Talajtan
Authors: László Simon, Marianna Makádi, György Vincze, Zsuzsanna Uri, Katalin Irinyiné Oláh, László Zsombik, Szabolcs Vígh, and Béla Szabó

A small-plot long-term field fertilization experiment was set up in 2011 with willow (Salix triandra x Salix viminalis ’Inger’) grown as an energy crop in Nyíregyháza, Hungary. The brown forest soil was treated three times (in June 2011, May 2013, May 2016) with municipal biocompost (MBC), municipal sewage sludge compost (MSSC) or willow ash (WA), and twice (June 2011, May 2013) with rhyolite tuff (RT). In late May – early June 2016 urea (U) and sulphuric urea (SU) fertilizers were also applied to the soil as top-dressing (TD). These fertilizers and amendments were also applied to the soil in 2016 in the combinations; MBC+SU, RT+SU, WA+SU and MSSC+WA. All the treatments were repeated four times. In July 2016 the highest nitrogen concentrations in willow leaves were measured in the U (3.47 m/m%) and SU (3.01 m/m%) treatments, and these values were significantly higher than the control (2.46 m/m%). An excess of nitrogen considerably reduced the Zn uptake of the leaves, with values of 39.5 μg g-1 in the U treatment, 53.4 μg g-1 in the SU treatment, and 63.5 μg g-1 in the control. All other amendments or TDs, except for WA, enhanced the specific potassium concentrations in willow leaves compared to the control. No significant quantities of toxic elements (As, Ba, Cd, Pb) were transported from soil amendments or TDs to the willow leaves. In July 2016 the most intensive leaf chlorophyll fluorescence was observed in the MSSC and MSSC+WA treatments.

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Agrokémia és Talajtan
Authors: László Simon, Marianna Makádi, Zsuzsanna Uri, Szabolcs Vigh, Katalin Irinyiné-Oláh, György Vincze, and Csilla Tóth

Open-field small plot long-term experiment was set up during 2011 with willow (Salix triandra × S. viminalis ‘Inger’), grown as a short rotation coppice energy crop in Nyíregyháza, Hungary. The sandy loam Cambisol with neutral pH was treated three times (2011, 2013, and 2016) with 15 t ha–1 municipal sewage sludge compost (MSSC) and with 600 kg ha–1 (2011, 2013) or 300 kg ha–1 (2016) wood ash (WA). In 2018 the MSSC-treated plots were amended with 7.5 t ha–1 municipal sewage sediment (MSS), and 300 kg ha–1 WA. MSSC and WA or MSS and WA were also applied to the soil in combinations during all treatments. Control plots remained untreated since 2011. Repeated application of wastewater solids (MSSC, MSS) and wood ash (WA) significantly enhanced the amounts of As (up to +287%), Ba, Cd (up to +192%), Cu, Mn, Pb, and Zn in the topsoil of willows. The combined application of MSSC+MSS+WA resulted in significantly higher Mn and Zn and lower As Ba, Cd Cr, and Pb concentrations in topsoil than MSSC+MSS treatment of soil without WA. Nitrogen concentrations in leaves of treated plants were generally slightly lower or similar to control. All soil treatments significantly enhanced the uptake or accumulation of nutrient elements (Ca, K, Mg, P) and potentially toxic elements (As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, and Zn) in the leaves of willows during 2018, 2019, and 2020. Significantly higher Mn or Zn concentrations were measured in MSSC+MSS+WA than in MSSC+MSS treatments. Significant amounts of Cd (up to 1.11 mg kg–1) or Zn (up to 183 mg kg–1) can be translocated (phytoextracted) from a soil amended with wastewater solids or wood ash to willow leaves. In 2018 the treatments decreased the chlorophyll fluorescence values, while in 2019 and 2020 the light adapted fluorescence yield (Y) values were higher in treated than in control plants.

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Progress in Agricultural Engineering Sciences
Authors: Péter Bor, József Csanádi, Gábor Veréb, Sándor Beszédes, Zita Šereš, Zsuzsanna László, Cecilia Hodúr, and Szabolcs Kertész

To meet the requirements defined by environmental protection regulations effective wastewater treatment is required to process effluents before discharging them into sewers or living waters. While membrane separation offers a quite advantageous method to reduce the organic load of wastewaters, membrane fouling is still limiting its application in wastewater treatment.

In this study, the possibility of membrane fouling reduction by increased shear rates on the surface of the membrane was investigated. 7 and 10 kDa MWCO ultrafiltration and 240 Da nanofiltration membranes were studied, with the use of a laboratory mode Vibratory Shear Enhanced Processing. This work mostly focused on studying the effects of module vibration and recirculation feed flow rate on permeate flux, specific energy demand and membrane rejections. Using the same operation parameters, vibration and non-vibration mode experiments were carried out with high and low recirculation flow rate to have a deeper understanding of the shear rate effects. It can be concluded that higher shear rate had a positive effect on the process: increased shear rate resulted in higher flux, higher overall rejection values, as well as a significantly decreased specific energy demand. By calculating and comparing the shear rates in experiments with different operating parameters, both vibration and nonvibration mode, both low and high recirculation flow rate, we have reached the conclusion that vibration causes a significantly higher shear rate increase than setting the recirculation flow rate high.

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Agrokémia és Talajtan
Authors: Péter Csathó, István Németh, Éva Bircsák, Zsuzsanna Földiné Németh, László Radimszky, and Tamás Németh
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Progress in Agricultural Engineering Sciences
Authors: Viktória Zsom-Muha, Lien Le Phuong Nguyen, László Baranyai, Géza Hitka, Zsuzsanna Horváth-Mezőfi, Gergő Szabó, and Tamás Zsom

Abstract

Among improper harvest and/or postharvest storage conditions, the effect of direct sunlight plays an important role in quality degradation of potato resulting in the development of green surface color based on chlorophyll formation associated with the formation of poisonous chemicals – glycoalcaloids – known as α-chaconine and α-solanine. Yellow skinned and fleshed potatoes with or without visible initial marks of green surface color were stored at normal room temperature under direct natural (sun)light conditions for almost two months. The aim of this study was the preliminary investigation of the sunlight induced formation of chlorophyll related compounds in potato indirectly by the detection of chlorophyll development. This attempt was based on nondestructive determination of chlorophyll related spectral and fluorescence indices for both sunlight exposed and unexposed potato sides. For both potato groups the chlorophyll content related DA-index® and chlorophyll fluorescence characteristics (F0, Fm, Fv and Fv/Fm) increased during the storage period representing chlorophyll formation. In the case of Fm, Fv and Fv/Fm values, the yellow samples reached the values of the initial spotted green samples by the 7th–9th days. From this time, the chlorophyll fluorescence values changed only minimally. After storage day 34, in the case of both at day 0 yellow and green spotted potatoes, the sunny side's F0 value was lower than that of shaded side. Close relationship was found between the results of Walz monitoring-PAM (Pulse Amplitude-Modulated) chlorophyll fluorometer and the PSI (Photon Systems Instruments) chlorophyll fluorescence imaging device (e.g. Fv R2 = 0.7226). According to our preliminary results, the Vis/NIR DA-meter®, the monitoring-PAM and the chlorophyll fluorescence imaging fluorometers were found to be suitable nondestructive devices for further investigations concerning the postharvest chlorophyll formation based greening phenomena, which is associated with solanine development in potato.

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