Anaerobic membrane reactor: Biomethane from chicken manure and high-quality effluent

Chicken manure was treated in a pilot scale reactor anaerobic membrane bioreactor constituted by a completely mixed reactor combined with an ultrafiltration tube-shaped membrane in a side-stream configuration. The process operated under mesophilic condition and the inhibition of high concentration of ammonia was avoided using an ammonia stripping system. The experimental plan included a preliminary evaluation, where organic loading rates between 1.0 and 7.6 kgVS/m3/day were tested. The organic load higher than 4 kgVS/m3/d caused the accumulation of volatile fatty acids and process instability. Application of the ammonia stripping was also evaluated. The best performances were achieved using a retention time of 21 days, an organic load between 1.4 and 2.0 kgVS/m3/d, and the recirculation of stripped permeate. Reduction of the ammonia permeate content by 90% through stripping and utilization of a mixture of chicken manure/water/permeate in a ratio of 0.22/0.72/0.72 w/w led to a specific biogas production of 0.59 m3biogas/kgVS and methane content of 66–69%. The ammonia thus removed can be recovered by sulphuric acid treatment as ammonium sulphate, which can be used as a fertilizer. The proposed configuration allowed satisfactory biogas production with appropriate methane percentages, recovery of ammonium sulphate, and a high-quality effluent

Characterization of cementitious granular materials produced from contaminated soils

In the present paper, an improved solidification/stabilization (S/S) process for the production of cement-based granular materials from contaminated soils is described. The presented method is based on the use of Portland cement as a binder and superplasticizers (SPs). The effectiveness of this process on the immobilization of inorganic hazardous wastes has been tested on a contaminated soil from an industrial site, showing high levels of several heavy metals and metalloids such as copper, zinc, arsenic and lead. At first, a characterization of the contamination was carried out. The nature and distribution of contaminants have been investigated in detail by means of SEM-EDS (scanning electron microscopy with energy dispersive spectroscopy) and micro-PIXE (particle-induced X-ray emission) chemical mapping, both in the original soil and in the cement grains after the S/S treatment. The coupling of the high imaging capabilities of SEM with the excellent detection limits of micro-PIXE, allowed the identification of several metal-bearing phases in the investigated samples. The analyses showed that the main source of pollution is related to the presence of \u3bcm- to mm-sized particles of inorganic compounds, employed as pigments or additives by the glass production plant formerly operating at the studied area. In a second stage, the physico-chemical properties of the granular S/S materials were evaluated by means of mechanical and leaching tests. In particular, the attention was focused on the role played by superplasticizers in the S/S process. For this purpose, the performances of samples produced following the presented method have been compared with those of similar grains prepared without the addition of superplasticizers. Due to the lower demand of mixing water, the samples produced using superplasticizers showed a general improvement of performances in terms of decreased porosity, reduced leaching of contaminants and improved mechanical properties. The laboratory tests that were carried out showed that the granular materials produced with this improved S/S technique may be suitable for an in-situ re-use as filler or concrete aggregate and may be employed in several other large scale applications

A challenge in wastewater monitoring: technologies and biomonitoring tools

The Water Framework Directive (WFD) and coastal transitional waters IN: A changing coast: challenge for the environmental policies. Littoral 2008, 9th International Conference, November 25-28 2008, Venice, Ital

An innovative stabilization/solidification treatment for contaminated soil remediation: demonstration project results

Background, aim, and scope: An innovative stabilization/solidification (S/S) process using high-performance additivated concrete technology was developed for remediating soil contaminated by metals from abandoned industrial sites. In order to verify the effectiveness of this new ex situ S/S procedure, an area highly contaminated by metallic pollutants (As, Cd, Hg, and Pb), due to the uncontrolled discharge of waste generated from artistic glass production on the island of Murano (Venice, Italy), was selected as a case study. The technique transforms the contaminated soil into an aggregate material suitable for reuse as on-site backfill. This paper reports the main results of the demonstration project performed in collaboration with the local environmental protection agency (ARPAV). Materials and methods: An ex situ treatment for brownfield remediation, based on the transformation of contaminated soil into very dense, low porous, and mechanically resistant granular material, was set up and tested. Specific additives (water reducers and superplasticizers) to improve the stabilized material properties were developed and patented. A demonstration plant assembled on the study area to treat 6 m3 h -1was then tested. After excavation, the contaminated soil was screened to remove coarse material. The fraction ∅>4 mm (coarse fraction), mainly composed of glass, brick, concrete, and stone debris, was directly reused on site after passing through a washing treatment section. The highly polluted fraction ∅ 4 mm (fine fraction) was treated in the S/S treatment division of the plant (European patent WO/2006/097272). The fine fraction was mixed with Portland cement and additives defined on the basis of the high performance concrete technique. the mixture was then granulated in a rolling-plate system. After 28 days curing in an onsite storage area to allow for cement hydration, the stabilized material was monitored before its in situ relocation. The chemical, mechanical, and ecotoxicological reliability and performance of the treatment was checked. Metal leachability was verified according to four leaching test methods: Italian Environmental Ministry Decree (1998), EN 12457 (2002) tout court, amended only with MgSO4 and, lastly, with artificial sea water. The mechanical properties were measured according to BS (1990) and AASHTO (1999) to obtain the Aggregate Crushing Value and California Bearing Ratio, in that order. Moreover, leachate samples prepared with artificial seawater were assessed via the Crassostrea gigas embryotoxicity test and Vibrio fischeri bioluminescence inhibition test to discriminate the presence of potential ecotoxicological effects for the brackish and saltwater biota. Results: Outcomes from all leachate samples highlighted the effectiveness of the remediation treatment, fully complying with the Italian legislation for non-hazardous material reuse under a physicochemical viewpoint. The stabilized granular material demonstrated high mechanical strength, low porosity, and leachability. Moreover, ecotoxicological surveys indicated the presence of low toxicity levels in leachate samples according to both toxicity tests. Discussion: Remediated soil samples revealed a significant decrease in leachability of heavy metals as a consequence of the application of additivated cement that enhanced granular material properties, resulting in improved compactness due to the reduction in water content. The toxicity data confirmed this state-of-the-art technique, indicating that leachates could be deemed as minor acutely toxic. Conclusions: The proposed S/S treatment proved to be able to remediate soil contaminated by heavy metals through trapping pollutants in pellet materials presenting adequate physicochemical, mechanical, and ecotoxicological properties in order to prevent leachability phenomena, their reclamation, and reuse being made easier by its granular form. Recommendation and perspectives: This project foresees long-term monitoring activity over several years (until 2014) to consider treatment durability

Consecutive thermal and wet conditioning treatments of sedimentary stabilized cementitious materials from HPSS® technology: Effects on leaching and microstructure

none8noSoil and sediment contamination is recognised as one of the most relevant environmental problems caused by past industrial activities and unsustainable waste disposal practices, highlighting the need to develop or improve effective remediation techniques to support sustainable management strategies. In this context, the remediation of sediments dredged from the Mincio river (Italy) contaminated by mercury and heavy hydrocarbons (C12-40) was carried out by applying and implementing the High Performance Solidification/Stabilization technology, aimed at producing safe and reusable cement-based granular materials. The technology was improved by decreasing both the temperature and time of the thermal desorption treatment (from 280 to 110 °C and from 4-16 h to 70 min, respectively) and by including a wet conditioning step to the process. Temperature and time reduction allowed to diminish the degradation of the cementitious phases of the granules (usually related to the high temperatures employed in the process), while the wet conditioning step allowed to improve their mechanical properties, as well as to further reduce the leaching of contaminants. The physical-chemical properties of the granules and contaminant leaching in water were investigated by Inductively Coupled Plasma Mass and Optical Emission Spectrometry, Ultraviolet–Visible spectroscopy, Gas Chromatography, X-Ray Powder Diffraction, and Scanning Electron Microscopy, in order to identify the optimal parameters for both thermal and wet conditioning processes. The overall results showed that the use of consecutive thermal and wet conditioning treatment on sedimentary cementitious materials from the High Performance Solidification/Stabilization technology led to the removal of volatile pollutants and to the improvement of granule quality, thus providing a final material that satisfied all the Italian regulatory requirements for reuse. Therefore, the findings obtained in this study may contribute to the development of sustainable management strategies for contaminated soils and sediments, leading to their valorisation through the transformation into reusable materials.noneCalgaro L.; Badetti E.; Bonetto A.; Contessi S.; Pellay R.; Ferrari G.; Artioli G.; Marcomini A.Calgaro, L.; Badetti, E.; Bonetto, A.; Contessi, S.; Pellay, R.; Ferrari, G.; Artioli, G.; Marcomini, A

A challenge in wastewater monitoring: technologies and biomonitoring tools

The Water Framework Directive (WFD) and coastal transitional waters IN: A changing coast: challenge for the environmental policies. Littoral 2008, 9th International Conference, November 25-28 2008, Venice, Ital

A challenge in wastewater monitoring: technologies and biomonitoring tools

The Water Framework Directive (WFD) and coastal transitional waters IN: A changing coast: challenge for the environmental policies. Littoral 2008, 9th International Conference, November 25-28 2008, Venice, Ital

A challenge in wastewater monitoring: technologies and biomonitoring tools

The Water Framework Directive (WFD) and coastal transitional waters IN: A changing coast: challenge for the environmental policies. Littoral 2008, 9th International Conference, November 25-28 2008, Venice, Ital

Acoustic sensing of renal stone fragmentation in extracorporeal shockwave lithotripsy

This thesis describes the research carried out by the author on the exploitation of acoustic emissions detected during extracorporeal shockwave lithotripsy (a non-invasive procedure for the treatment of urinary stones) to develop a new diagnostic system. The work formed part of a research project on lithotripsy undertaken by the University of Southampton in collaboration with Guy's and St Thomas' NHS Foundation Trust (London) and a UK based company, Precision Acoustics Ltd (Dorchester). It takes to a clinical conclusion the proposition made by Leighton and Coleman in 1992 that it might be possible to build a sensor which would automatically exploit these passive acoustic emissions to monitor the efficacy of a lithotripsy treatment. The work, predominantly experimental, involved both in vitro and in vivo investigations. In particular, a first prototype diagnostic system (i.e. sensor plus analysis software) was developed and tested in vitro during trials which included the use of a novel cavitation sensor (on loan from the National Physical Laboratory, Teddington) and stone phantoms designed by the author. This initial system was, then, refined and tested during clinical trials that involved 130 patients. A preliminary trial on 51 patients aimed at refining the system and gathering knowledge on the features of emissions recorded in vivo to produce an on-line monitoring system. This trial was followed by other two trials that compared the output of the on-line acoustic system against the ‘gold standard’ X-Ray assessment of treatments outcomes. The former of these two trials involved 30 patients, and empirically defined the values of the key parameters (identified during the in vitro tests) that would be used as the basis of the diagnosis. In particular, a classification rule of treatments as being successful or unsuccessful was identified, and shown to agree significantly (kappa=0.95) with the ‘gold standard’ follow-up assessment. The latter trial tested the final system on 49 patients and confirmed an accurate treatment classification (kappa=0.94) in terms of the successful/unsuccessful criterion.EThOS - Electronic Theses Online ServiceGBUnited Kingdo