Wyniki wyszukiwania - Biblioteka Nauki

1

Study of the Biodegrability of Degradable/Biodegradable Plastic Material in a Controlled Composting Environment

100%

Vaverková M. , Toman F. , Adamcová D. , Kotovicová J.

|

tom 19

|

nr 3

347-358

EN

The objective of this study was to determine the degrability/biodegradability of disposable plastic bags available on the market that are labeled as degradable/biodegradable and those certified as compost. The investigated materials were obtained from chain stores in the Czech Republic and Poland. Seven kinds of bags (commercially available) were used in this study. One of them was a disposable bag made of HDPE and mixed with totally degradable plastic additive (TDPA additive). Another was a disposable made of polyethylene with the addition of pro-oxidant additive (d2w additive). One was labeled as 100% degradable within various periods of time, from three months up to three years, and four were certified as compostable. The test was carried out in a controlled composting environment. The biodisintegration degree of the obtained pieces was evaluated following a modified version of ČSN EN 14806 Norm "Packaging - Preliminary evaluation of the disintegration of the packaging materials under simulated composting conditions in a laboratory scale test" and a modified version of ČSN EN ISO 20200 "Plastics - Determination of the degree of disintegration of plastic materials under simulated composting conditions in laboratory-scale test" (ISO 20200:2004). The emphasis was put on determination whether the bags are degradable/biodegradable or not.

PL

Celem badań było określenie degradacji/biodegradacji "jednorazowych" plastikowych toreb dostępnych na rynku, które są oznaczone jako degradowalne/biodegradowalne, jak również toreb certyfikowanych jako nadające się do kompostowania. Badane materiały są dostępne w sieci sklepów w Czechach oraz w Polsce. Badaniu poddano siedem próbek. Jedną z nich była jednorazowa torba wykonana z folii HDPE (polietylenu łatwo degradowalnego) z dodatkiem TDPA (powodującego całkowitą degradację folii polietylenowej). Badano też torby wykonane z różnymi dodatkami, co powodowało ich rozkład w określonym czasie. Testy zostały przeprowadzone w kontrolowanych warunkach kompostowania. Stopień rozkładu określono za pomocą zmodyfikowanej wersji normy ČSN EN 14806 "Opakowania - Ocena wstępna rozpadu materiałów opakowaniowych w symulowanych warunkach kompostowania w badaniach w skali laboratoryjnej" oraz zmodyfikowanej wersji normy ČSN EN ISO 20200 "Tworzywa sztuczne - Oznaczanie stopnia rozpadu tworzyw sztucznych w symulowanych warunkach kompostowania w skali laboratoryjnej" (ISO 20200:2004). Głównym celem badań było określenie, czy jednorazowe torby ulegają degradacji/biodegradacji czy nie.

2

THE EFFECT OF BIODEGRADATION/DEGRADATION OF DEGRADABLE PLASTIC MATERIAL ON COMPOST QUALITY

100%

Adamcová D. , Toman F. , Vaverková M. , Kotovicová J.

|

nr 4

783-798

EN

The objective of this study was to find out whether the quality of compost would change during the process of composting carrier bags claimed by manufacturers as compostable or biodegradable in terms of parameters stipulated in the standard ČSN 46 5735 Industrial composts. Eight samples were subjected to the composting process in laboratory conditions. The compost samples were analyzed in the accredited laboratory. All samples met parameters stipulated for Class II. Seven samples of the eight met parameters stipulated in the standard ČSN 46 5735 for Class I. The samples had no influence on compost characteristics: strength, content of water and salt, pH value, content of nutrients or proportion of organic substances; other components of the compost remained unchanged. Optical changes of the compost did not occur either.

PL

Celem badań było określenie wpływu procesu kompostowania „jednorazowych” plastikowych toreb dostępnych na rynku, które są oznaczone jako biodegradowalne/degradowalne, jak również toreb certyfikowanych jako nadające się do kompostu, na jakość kompostu oraz dotrzymania wymagań określonych w normie CSN 46 5735 Komposty przemysłowe. Osiem próbek poddano procesowi kompostowania w warunkach laboratoryjnych. Próbki powstałego kompostu analizowano w akredytowanym laboratorium. Wszystkie próbki spełniały parametry określone w normie dla klasy II. Siedem z ośmiu próbek spełniało parametry określone w normie CSN 46 5735 dla klasy I. Próbki poddane recyklingowi organicznemu nie miały wpływu na właściwości kompostu: konsystencję, zawartość wody i soli, wartość pH, zawartość składników odżywczych lub stosunek substancji organicznych; składniki kompostu pozostały niezmienione. Nie zaobserwowano także zmian w wyglądzie kompostu

3

Influence of Fertilization on Microbial Activities, Soil Hydrophobicity and Mineral Nitrogen Leaching

63%

Elbl J. , Vaverková M. , Adamcová D. , Plošek L. , Kintl A. , LošÁk T. , Hynšt J. , Kotovicová J.

|

nr 4

661-675

EN

This work presents the analysis of the influence of compost and reclamation substrate addition and mineral fertilizers application on leaching of mineral nitrogen, microbial activities, soil hydrophobicity and plant biomass production. To demonstrate the effect of compost, reclamation substrate and mineral nitrogen (Nmin) addition on above parameters, the pot experiment was performed. As a model crop, Deschampsia caespitosa L. was used and cultivated for 63 days in climate chamber. The leaching of Nmjn was measured by application of ion exchange discs, soil hydrophobicity was determined based on the values of saturated hydraulic conductivity (Ksat) and microbial activity was expressed as basal (BR) and substrate induced respiration (SIR). Four variants (V1-V4) with different doses of fertilizers were prepared: V1 - control without addition of fertilizers; V2 - this variant of experiment was prepared as mixture of compost and arable land in ratio 7:3; V3 - 90 g/m2 of mineral fertilizers NPK (in the ratio 1:1:1) were applied there and into V4, dose 30 g of compost were applied. The significant differences (P < 0.05) in the detection of Nmin, values of Ksat and SIR were found. The highest decrease of mineral nitrogen leaching was observed by the simultaneous applications of compost (V4) to arable soil, about 50% in comparison with the variant V4 (application of mineral fertilization) and about 10% in comparison with the control. Variants with addition of compost (V2 and V4) showed higher values than variants without, which were measured at three stages (before application of Nmin - 12 days after establishment of the experiment; after application of Nmin - 34 days; at end of the experiment - 63 days). During the experiment, two types of respiration were measured: BR and SIR. The significant differences in SIR were found between variants with addition of compost and variants without. The SIR (cumulative production of CO2) was higher about 25% in variants V2 and V4 compared to variants V1 and V3. The highest values of Ksat were found in variants with addition of compost. Conversely, the lowest value of Ksat was detected in variant with addition of Nmin. Low values of Ksat indicate an increased level of hydrophobicity.