Case study on phytoremediation driven energy crop production using Sida hermaphrodita.

The cultivation of energy crops on heavy metals contaminated (HMC) areas offer opportunities, which combine site remediation with energy recovery. Numerous tests have been conducted using phytoremediation in HMC soils with energy crop species. Sida hermaphrodita L. Rusby, has shown potential as an energy crop useful in the phytoextraction of HMs. The aim of the study was to investigate the efficiency of using S. hermaphrodita in energy crop production in HMs contaminated sites. The study investigated the impact of different fertiliser treatments on the composition of elements in cultivated biomass on HMC arable land and sewage sludge dewatering sites to determine its suitability for energy production in gasification processing. It was found that S. hermaphrodita is a species accumulating HMs mainly due to their bioavailability in soil (Cd r = 0.877, Zn r = 0.876). Calculated Cd and Zn bioaccumulation factors for plants cultivated on HMC arable land were 12-fold and 18-fold higher respectively, when compared to a sewage sludge dewatering site. Lower heating value of biomass was higher by about 7% for biomass cultivated on HMC arable land. Despite the presence of HMs in ash after the gasification process, some of it could be used as fertilizer, especially on heavy metal contaminated sites.

Sewage sludge as a fuel and raw material for phosphorus recovery: Combined process of gasification and P extraction.

Increasing problems associated with sewage sludge disposal are observed nowadays. As the thermal conversion of sewage sludge (combustion, co-combustion, gasification and pyrolysis) appears to be the most promising alternative for its management, the solid residues left after gasification were examined. The present study evaluates the potential of this waste as an alternative phosphorus source in the context of phosphorus recovery. The obtained solid gasification residues were characterised (chemical and phase composition, thermal properties, surface properties and technological parameters used for phosphorus raw materials) and compared to commercial phosphate raw materials. It was revealed that gasification residue is a valuable source of phosphorus and microelements, comparable to sewage sludge ash (SSA) considered nowadays as secondary phosphorus raw materials. Chemical properties as well as technological parameters characteristic for natural phosphate ores are different. Solid gasification residue was leached with mineral acids (phosphoric and nitric) according to the patented method of phosphorus recovery - PolFerAsh, developed by Cracow University of Technology. It was revealed that phosphorus can be selectively leached from solid gasification residue with high efficiency (73-82%); moreover, most of the iron and heavy metals stay in the solid phase due to the low concentration of acids and proper solid to liquid phase ratio. The obtained leachates are valuable products that can be considered for the production of fertilisers. Combining the gasification process with nutrient recovery provides the opportunity for more environmentally efficient technologies driven by sustainable development rules.

Age- and gender-specific normative data of grip and pinch strength in a healthy adult Swiss population.

Assessment of hand strength is used in a wide range of clinical settings especially during treatment of diseases affecting the function of the hand. This investigation aimed to determine age- and gender-specific reference values for grip and pinch strength in a normal Swiss population with special regard to old and very old subjects as well as to different levels of occupational demand. Hand strength data were collected using a Jamar dynamometer and a pinch gauge with standard testing position, protocol and instructions. Analysis of the data from 1023 tested subjects between 18 and 96 years revealed a curvilinear relationship of grip and pinch strength to age, a correlation to height, weight and significant differences between occupational groups. Hand strength values differed significantly from those of other populations, confirming the thesis that applying normative data internationally is questionable. Age- and gender-specific reference values for grip and pinch strength are presented.