Increasing market opportunities for renewable energy technologies with innovations in aquifer thermal energy storage.

Heating and cooling using aquifer thermal energy storage (ATES) has hardly been applied outside the Netherlands, even though it could make a valuable contribution to the energy transition. The Climate-KIC project "Europe-wide Use of Energy from aquifers" - E-USE(aq) - aimed to pave the way for Europe-wide application of ATES, through the realization and monitoring of six ATES pilot plants across five different EU countries. In a preceding paper, based on preliminary results of E-USE(aq), conclusions were already drawn, demonstrating how the barriers for this form of shallow geothermal energy can be overcome, and sometimes even leveraged as opportunities. Based on final pilot project results, key economic and environmental outcomes are now presented. This paper starts with the analysis of specific technological barriers: unfamiliarity with the subsurface, presumed limited compatibility with existing energy provision systems (especially district heating), energy imbalances and groundwater contamination. The paper then shows how these barriers have been tackled, using improved site investigation and monitoring technologies to map heterogeneous subsoils. In this way ATES can cost-efficiently be included in smart grids and combined with other sources of renewable (especially solar) energy, while at the same time achieving groundwater remediation. A comparative assessment of economic and environmental impacts of the pilots is included, to demonstrate the sustainability of ATES system with different renewables and renewable-based technologies. The paper concludes with an assessment of the market application potential of ATES, including in areas with water scarcity, and a review of climate beneficial impact.

Sediment management in coastal infrastructures: Techno-economic and environmental impact assessment of alternative technologies to dredging.

The presence of anthropic activity in the coastal or riverine environment modifies the wave as well as the water and sediment current regime. In particular, the body of water around ports is an area where intense currents and sediment transport rates are usually present and can be affected by low water velocities that take place close to the entrance and inside the port basin. Consequently, sediment can be entrained and accumulated in such areas, creating problems to navigation. Ports and moorings are filled with fine sediments due to deposition resulting from solid transport. In particular, silt particles settle because of the weak vertical and lateral shearing of the velocity field. The result is that harbours frequently require ordinary maintenance dredging. The dredging process involves the removal of sediment in its natural deposited condition by using either mechanical or hydraulic equipment. Dredging is a consolidated and proven technology, but involves considerable drawbacks. In particular, dredging has a notable environmental impact on marine flora and fauna, contributes to the mobility and diffusion of contaminants and pollutants already present in the silted sediments, obstructs navigation and is characterized by relatively high and low predictable costs. This paper aims to provide an original structured overview of technologies alternative to dredging that have been tested in the past 50 years. More than 150 articles have been analysed to compare standard dredging technologies with market-ready competitors from techno-economic and environmental perspectives. In particular, the paper focuses on anti-sedimentation infrastructures and on innovative plant solutions characterized by low maintenance costs and by a very limited environmental impact. The final aim of the paper is to describe the currently available technologies that prevent port inlet and channel siltation and to classify them through a techno-economic and environmental impact assessment. The comparison shows that dredging has both the higher costs and environmental impact, while fixed sand by-passing plants are characterized by the lowest environmental impact and operation costs that are competitive with dredging.

Sewage sludge drying process integration with a waste-to-energy power plant.

Dewatered sewage sludge from Waste Water Treatment Plants (WWTPs) is encountering increasing problems associated with its disposal. Several solutions have been proposed in the last years regarding energy and materials recovery from sewage sludge. Current technological solutions have relevant limits as dewatered sewage sludge is characterized by a high water content (70-75% by weight), even if mechanically treated. A Refuse Derived Fuel (RDF) with good thermal characteristics in terms of Lower Heating Value (LHV) can be obtained if dewatered sludge is further processed, for example by a thermal drying stage. Sewage sludge thermal drying is not sustainable if the power is fed by primary energy sources, but can be appealing if waste heat, recovered from other processes, is used. A suitable integration can be realized between a WWTP and a waste-to-energy (WTE) power plant through the recovery of WTE waste heat as energy source for sewage sludge drying. In this paper, the properties of sewage sludge from three different WWTPs are studied. On the basis of the results obtained, a facility for the integration of sewage sludge drying within a WTE power plant is developed. Furthermore, energy and mass balances are set up in order to evaluate the benefits brought by the described integration.

Material and energy recovery in integrated waste management system--an Italian case study on the quality of MSW data.

This paper analyses the way numerical data on Municipal Solid Waste (MSW) quantities are recorded, processed and then reported for six of the most meaningful Italian Districts and shows the difficulties found during the comparison of these Districts, starting from the lack of homogeneity and the fragmentation of the data indispensable to make this critical analysis. These aspects are often ignored, but data certainty are the basis for serious MSW planning. In particular, the paper focuses on overall Source Separation Level (SSL) definition and on the influence that Special Waste (SW) assimilated to MSW has on it. An investigation was then necessary to identify new parameters in place of overall SSL. Moreover, these parameters are not only important for a waste management system performance measure, but are fundamental in order to design and check management plan and to identify possible actions to improve it.

Hot waste-to-energy flue gas treatment using an integrated fluidised bed reactor.

This paper describes an innovative process to increase superheated steam temperatures in waste-to-energy (WTE) plants. This solution is mainly characterised by a fluidised bed reactor in which hot flue gas is treated both chemically and mechanically. This approach, together with gas recirculation, increases the energy conversion efficiency, and raises the superheated steam temperature without decreasing the useful life of the superheater. This paper presents new experimental data obtained from the test facility installed at the Hera S.p.A. WTE plant in Forlì, Italy; discusses changes that can be implemented to increase the duration of experimental testing; offers suggestions for the design of an industrial solution.

[Prevalence of changes in performance, subjective symptoms and occupational dermatitis before and after carrying out improvements in the surgical block of the Modena Polyclinic]. / Prevalenza di alterazioni delle performances, sintomi soggettivi e dermopatie professionali prima e dopo interventi di bonifica di un blocco operatorio del Policlinico di Modena.

The Preventive Medicine Unit for Personnel in the USL N. 16 of Modena has conducted a study to evaluate the prevalence of subjective symptoms and professional dermatitis among nurses working in a general surgery operating theatre of the Modena "Policlinico" Hospital (36 and 41 employees were studied respectively in 1990 and 1991), before and after the installation of gas evacuators and a modification in the use of detergent and disinfectant substances. The study demonstrates that installation of gas evacuating systems, if not supported by an intervention of air-conditioning plant, does not sufficiently reduce alterations in subjective symptoms. On the other hand, the modifications in the use of detergent and disinfectants has demonstrated a favourable reduction in the prevalence of professional dermatitis (from 43% to 18%; chi2 = 4.35, p = 0.037).

[Urinary measurement of D-glucaric acid in operating room personnel in the Modena USL 16 hospitals]. / Dosaggio urinario di acido D-glucarico nel personale di sala operatoria degli ospedali dell'USL 16 di Modena.

The Authors describe the results of a research conducted in order to evaluate the amount of D-glucaric acid in the urine of 131 operating theatre workers exposed to anesthetic gases and in a control group of 25 non-exposed hospital personnel. The comparison of the results of the two groups points out a significant difference (in the exposed members 60.7 +/- 2.4 mumol/1 to 46.7 +/- 4.3 mumol/l [+/- s.e.] in the control group; t-test: p = 0.016). The research also considered the influence of certain variables such as age, sex, smoking, alcohol, drug use and liver disorders. None of these variables has proven to be of significant influence on the D-glucaric acid urinary concentration.