The paper deals with an innovative strategy and methodology to globally improve the wastewater treatment and management in a whole water basin district, where a large network of 73 treatment plants, mostly small and decentralized, are operating. The network of wastewater treatment plants (WWTPs) was analysed to outline the current state of the wastewater treatment and management. These detailed analyses were used by the competent authority to identify the critical aspects and assess the call for tender regarding the wastewater treatment and management. The call is focused on two main concepts: (1) scientific approach and technological innovation for trouble-shooting and WWTPs upgrading; (2) periodical verification and validation of the results achieved, according to protocols proposed by the tenderers. Therefore, the response of the tenderers was mainly based on the alternate cycles processes to improve the secondary effluent quality in terms of nitrogen and phosphorus content, reduce the waste activated sludge production and consumptions of electric energy. Additionally, locals adoption of waste sludge ozonization will contribute to achieve the global results in the whole water basin district.

The paper deals with the results obtained as nitrogen removal and energy savings in a wastewater treatment plant located in the Province of Trento where the vineyards grow on about 1,500 ha (19% of total vineyards of the Province). In the plant the municipal and pre-treated winery wastewater were co-treated. The optimal effluent quality and the reduction of energy consumption were achieved changing the total oxidation process to an alternate cycles (AC) one and applying a remote control system for three months. The characterization of the influent highlighted a remarkable variability of the mass loads mainly determined by the cyclic winemaking periods. The AC application allowed the system to cope with the intense variations of influent nitrogen loadings and to obtain a stable quality of the effluent with an average TN concentration less than 10 mg NL(-1). The nitrogen loading rate (NLR) up to 0.227 Kg TN m(-3) d(-1) was tolerated by the elevated AC control level device to assure successful denitrification performances (from 70% to 90%) also in conditions of COD/TN lower than 7. Comparing the AC with the pre AC conditions, a total energy saving in the range of 13-23% was estimated. Moreover, the specific energy consumptions were reduced to 59% despite the increment of the influent mass loadings.

The paper deals with the real application of a strategy, based on process control automation and remote on-line supervision, for the wastewater treatment in a piedmont. Three existing small wastewater treatment plants were selected to be upgraded and to be included into a network remotely supervised. Further, the potentialities of the process control automation were enhanced by the appropriate upgrading of the whole plant. A consolidated alternating nitrification and denitrification process was applied for the biological treatment. The selected plants well represent the area of Autonomous Province of Trento because they are characterized by remarkable seasonal fluctuation. After five months of experimentation data processed show the real stable high quality of the treated effluent in terms of total nitrogen content. Moreover, the power requirements are significantly reduced according the correct energy policy. The performances of the new biological process applied and the economical balance, put in evidence the gain by chosing the AC technology for upgrading small WWTPs.

In most cases of winery effluent, the heavy metal content, especially zinc (Zn) and copper (Cu), does not meet the limits for the discharge as imposed by the most restrictive regulations at international level (0.4 mgCu/L and 1.0 mgZn/L in the Italian regulations). An alternative for the reduction of Cu and Zn is the on-site pre-treatment of wastewater at the winery in order to meet the limits for the discharge into the public sewerage. The purpose of this study is to evaluate the effectiveness of a pre-treatment based on chemical precipitation with chelating agents (TMT: 2,4,6-trimercaptotriazine), for the reduction of Cu and Zn from raw winery wastewater. The chemical precipitation was optimised at lab-scale through jar tests in order to evaluate the optimal dosages. An average dosage equal to 0.84 mL of TMT (15%) for 1 mg of Cu removed was estimated. Furthermore, the efficiency of the on-site chemical pre-treatment was investigated at pilot scale. The results confirmed the feasibility of using TMT treatment for the reduction of Cu and Zn in order to meet the limits for discharge into the sewerage. Contextually to the removal of heavy metals, the chemical pre-treatment allowed us to obtain the reduction of particulate COD and TSS. Finally, the costs for the operation and the management of the on-site pre-treatment were evaluated.

The treatment of winery wastewater was performed at full-scale applying a two-stage fixed bed biofilm reactor (FBBR) system for the discharge in the sewerage. The results of the first year of operation at the full-scale plant are presented. Values of removed organic loads and effluent concentrations were interpreted on the basis of the COD fractionation of influent wastewater assessed through respirometric tests. The average removal efficiency of total COD was 91 %. It was not possible to reach an higher efficiency because of the unbiodegradable soluble fraction of COD (about 10% of total COD on average during the whole year), that cannot be removed by biological process or settling. Due to the high empty space offered by the plastic carriers, FBBRs did not require backwashing during the seasonal operationing period of the plant (September-March). In comparison with other treatment systems the FBBR configuration allows one to ensure a simple management, to obtain high efficiency also in the case of higher fluctuations of flow and loads and to guarantee a good settleability of the sludge, without bulking problems.

The aim of this research was the application of a biofilm system for the upgrading of a full-scale overloaded activated sludge MWWTP using the MBBR (Moving Bed Biofilm Reactor) technology. The choice of this fixed biomass system appeared appropriate because it offers several advantages including good potential in nitrification process, easiness of management and above all, the possibility to use the existing tank with very few modifications. MBBR system counts only few full-scale plants in Italy at the moment, thus a pilot-scale experimentation was preliminarily carried out. The acquired parameters were used for the fullscale MWWTP upgrading. The upgrading of the activated sludge reactor in the MBBR system has given (1) a relevant increase in the flowrate treated up to 60%; (2) a good efficiency in organic carbon removal and nitrification, equal to 88% and 90% respectively, with HRTs of 5.5-7 h; (3) the overcoming of the hydraulic overload of the secondary settler, applying a lamellar settler. It was observed a good correlation between the results obtained at pilot-scale and those observed in the full-scale plant.

Tourists visiting mountain refuges in the Alps have increased significantly in the last decade and the number of refuges and huts at high altitude too. In this research the results of an intensive monitoring of a wastewater treatment plant (WWTP) for a tourist mountain refuge located at 2,981 m a.s.l. are described. Two biofilm reactors were adopted: (a) a Moving Bed Biofilm Reactor (MBBR); (b) a submerged Fixed Bed Biofilm Reactor (FBBR). The aims of this research were: (i) the evaluation of the main parameters characterising the processes and involved in the design of the wastewater plants, in order to compare advantages and disadvantages of the two tested alternatives; (ii) the acquisition of an adequate knowledge of the problems connected with the wastewater treatment in alpine refuges. The main results have been: (i) a quick start-up of the biological reactors obtainable thanks to a pre-colonization before the transportation of the plastic carriers to the refuge at the beginning of the tourist season; (ii) low volume and area requirement; (iii) significantly higher removal efficiency compared to other fixed biomass systems, such as trickling filters, but the energy consumption is higher.