Effect of Compatibilizing Agent on the Properties of Highly Crystalline Composites Based on Poly(lactic acid) and Wood Flour and/or Mica

This article contains a concept of the mechanical properties improvement of the highly crystalline poly(lactic acid) (PLA) and filled composites. PLA as a semi-crystalline thermoplastic polymer was plasticized with poly(ethylene glycol) and filled with 30 vol% of organic and/or inorganic filler. The degree of crytallinity was intentionally increased by annealing. The filler/polymer matrix interphase was modified with the addition of 4, 4′-Methylenediphenyl diisocyanate (MDI). The effect of compatibilizing as well as plasticizing agent on the thermal and mechanical properties, the water-absorption behaviour and crystallization characteristics were studied. The results indicated that high content of filler and crystallites have a strong influence on the composite′s mechanical properties despite of the plasticizer content, showing a high Young modulus. The MDI seems to react in preference easy with plasticizing agent and then alternatively with filler due to the low functionality of commercial PLA grade.     

Pimp Your Landscape: A Tool for Qualitative Evaluation of the Effects of Regional Planning Measures on Ecosystem Services

The article presents the platform “Pimp your landscape” (PYL), which aims firstly at the support of planners by simulating alternative land-use scenarios and by an evaluation of benefits or risks for regionally important ecosystem services. Second, PYL supports an integration of information on environmental and landscape conditions into impact assessment. Third, PYL supports the integration of impacts of planning measures on ecosystem services. PYL is a modified 2-D cellular automaton with GIS features. The cells have the major attribute “land-use type” and can be supplemented with additional information, such as specifics regarding geology, topography and climate. The GIS features support the delineation of non-cellular infrastructural elements, such as roads or water bodies. An evaluation matrix represents the core element of the system. In this matrix, values in a relative scale from 0 (lowest value) to 100 (highest value) are assigned to the land-use types and infrastructural elements depending on their effect on ecosystem services. The option to configure rules for describing the impact of environmental attributes and proximity effects on cell values and land-use transition probabilities is of particular importance. User interface and usage of the platform are demonstrated by an application case. Constraints and limits of the recent version are discussed, including the need to consider in the evaluation, landscape-structure aspects such as patch size, fragmentation and spatial connectivity. Regarding the further development, it is planned to include the impact of land management practices to support climate change adaptation and mitigation strategies in regional planning.     

Limitations for heavy metal release during thermo-chemical treatment of sewage sludge ash

Phosphate recycling from sewage sludge can be achieved by heavy metal removal from sewage sludge ash (SSA) producing a fertilizer product: mixing SSA with chloride and treating this mixture (eventually after granulation) in a rotary kiln at 1000 ± 100 °C leads to the formation of volatile heavy metal compounds that evaporate and to P-phases with high bio-availability. Due to economical and ecological reasons, it is necessary to reduce the energy consumption of this technology. Generally, fluidized bed reactors are characterized by high heat and mass transfer and thus promise the saving of energy. Therefore, a rotary reactor and a fluidized bed reactor (both laboratory-scale and operated in batch mode) are used for the treatment of granulates containing SSA and CaCl₂. Treatment temperature, residence time and - in case of the fluidized bed reactor - superficial velocity are varied between 800 and 900 °C, 10 and 30 min and 3.4 and 4.6 m s⁻¹. Cd and Pb can be removed well (>95 %) in all experiments. Cu removal ranges from 25% to 84%, for Zn 75-90% are realized. The amount of heavy metals removed increases with increasing temperature and residence time which is most pronounced for Cu.In the pellet, three major reactions occur: formation of HCl and Cl₂ from CaCl₂; diffusion and reaction of these gases with heavy metal compounds; side reactions from heavy metal compounds with matrix material. Although, heat and mass transfer are higher in the fluidized bed reactor, Pb and Zn removal is slightly better in the rotary reactor. This is due the accelerated migration of formed HCl and Cl₂ out of the pellets into the reactor atmosphere. Cu is apparently limited by the diffusion of its chloride thus the removal is higher in the fluidized bed unit.     

Invasion costs,impacts, and human agency: response to Sagoff 2020

Article impact statement: In an era of profound biodiversity crisis, invasion costs, invader impacts, and human agency should not be dismissed.