Giovanni De Feo

Public opinion and awareness towards MSW and separate collection programmes: A sociological procedure for selecting areas and citizens with a low level of knowledge

The principal aim of this study was to define and apply a procedure based on a structured questionnaire survey useful to analyze the peoples environmental knowledge in order to select the areas and age groups with a low level of knowledge in a municipality (in Southern Italy) and, therefore, suggest a specific educational campaign for each. The detailed sampling procedure made it possible to carry out a meticulous statistical analysis of the results. The youngest and oldest people showed the lowest level of awareness for each district. A high level of education did not necessarily imply a high level of environmental awareness as well as a greater acceptance of MSW facilities. The satisfaction level of the recycling program was higher amongst the oldest age group. All the citizens in the several areas were unanimous in pointing out the presence of dirt in the street as the main shortcoming of the bring separate collection program. Only the youngest age group self-criticised, considering that they revealed a low level of participation to the separate collection program. While, the oldest people retaining them less influential, claimed that the citizens were not responsible for the failure of the separate collection program. The prevailing opinion of the sample was that people protested against the construction of waste facilities because they were not well-informed, with the most significant opinion of all the age subdivisions being that incineration is a hazardous treatment. The presence of criminal organizations was indicated as the main reason why the Campania Region suffers a serious solid waste emergency. While, the percentage of people pointing their finger at politicians increases with the average age of the respondents with there being a very strong correlation (r(2)=0.9903).

Siting landfills and incinerators in areas of historic unpopularity: Surveying the views of the next generation

The Campania Region in Southern Italy has suffered many problems with municipal solid waste management since the mid-1990s, leading to significant public disturbances and subsequent media coverage. This paper reports on the current views and knowledge of young people (university students) in this region about waste management operations and facilities, specifically the siting of landfills and incinerators. By means of a structured questionnaire, opinion and knowledge were systematically examined by degree type and course year. The study took place in 2011 at the University of Salerno campus. A sample of 900 students, comprising 100 students for each of the nine considered faculties, and 20 students for every academic course year, was randomly selected. Only about a quarter of respondents were not opposed to the siting of a landfill or an incinerator in their city. This clearly highlights that historic opposition to the construction of waste facilities is difficult to overcome and that distrust for previous poor management or indiscretions is long-lived and transcends generations. Students from technical faculties expressed the most reasonable opinion; opinion and knowledge were statistically related (Chi-square test, p<0.05) to the attended faculty, and the knowledge grew linearly with progression through the university. This suggests that awareness of waste management practices develops with experience and understanding of environmental issues. There is general acceptance that many stakeholders - technicians, politicians and citizens - all have to be part of the decision process when siting a new waste management facility. The opinions of the young respondents were significantly influenced by their level of environmental knowledge.

Full-scale treatment of wastewater from a biodiesel fuel production plant with alkali-catalyzed transesterification

The treatment of wastewater derived from a biodiesel fuel (BDF) production plant with alkali-catalyzed transesterification was studied at full scale. The investigated wastewater treatment plant consisted of the following phases: primary adsorption/coagulation/flocculation/sedimentation processes, biological treatment with the combination of trickling filter and activated sludge systems, secondary flocculation/sedimentation processes, and reverse osmosis (RO) system with spiral membranes. All the processes were developed in a continuous mode, while the RO experiment was performed with batch tests. Two types of BDF wastewater were considered: the first wastewater (WW1) had an average total chemical oxygen demand (COD), pH and feed flow rate of 10,850.8 mg/L, 5.9 and 2946.7 L/h, respectively, while the second wastewater (WW2) had an average total COD, pH and feed flow rate of 43,898.9 mg/L, 3.3 and 2884.6 L/h, respectively. The obtained results from the continuous tests showed a COD removal percentage of more than 90% for the two types of wastewater considered. The removal of biorefractory COD and salts was obtained with a membrane technology in order to reuse the RO permeate in the factory production cycle. The rejections percentage of soluble COD, chlorides and sulphates were 92.8%, 95.0% and 99.5%, respectively. Because the spiral membranes required a high number of washing cycles, the use of plane membranes was preferable. Finally, the RO reject material should be evaporated using the large amount of inexpensive heat present in this type of industry.

Performance of vegetated and non-vegetated vertical flow reed beds in the treatment of diluted leachate

This study was undertaken to investigate the behaviour of a vertical flow reed bed system with 3 kind of wastewaters (W1, W2 and W3) and for two hydraulic retention times (3 and 7 days) as well as to assess the role of Phragmites Australis in constructed wetland treatment processes. The adopted batch experimental system consisted of six vertical flow filters, filled with granular media and planted with reeds. For each vegetated reactor there was a correspondent blank in order to make a comparison. Wastewaters were obtained mixing tap water, MSW landfill leachate and activated sludge in different percentages. W1, W2 and W3 were designed in order to reproduce treated or untreated wastewaters not in compliance with legislation in force (Directive 91/271/EEC), with increasing level of NH4 +-N from W1 (16.3 mg/L) to W3 (76.0 mg/L). In average terms, 3 days was sufficient for W1 and W2 to face the compliance limits; while, for W3 even 7 days was not sufficient to respect the compliance limit for ammonia nitrogen (1.4 times greater). The obtained results shown that the vegetation played an essential role especially in the removal of nitrogen: for the wastewater with the highest loads the contribution of reeds in the removal of nitrogen was greater than that of biofiltration processes. The contribution of the vegetation was also detectable in the removal of orthophosphate, but with minus efficiency.This study was undertaken to investigate the behaviour of a vertical flow reed bed system with 3 kind of wastewaters (W1, W2 and W3) and for two hydraulic retention times (3 and 7 days) as well as to assess the role of Phragmites Australis in constructed wetland treatment processes. The adopted batch experimental system consisted of six vertical flow filters, filled with granular media and planted with reeds. For each vegetated reactor there was a correspondent blank in order to make a comparison. Wastewaters were obtained mixing tap water, MSW landfill leachate and activated sludge in different percentages. W1, W2 and W3 were designed in order to reproduce treated or untreated wastewaters not in compliance with legislation in force (Directive 91/271/EEC), with increasing level of NH4 +-N from W1 (16.3 mg/L) to W3 (76.0 mg/L). In average terms, 3 days was sufficient for W1 and W2 to face the compliance limits; while, for W3 even 7 days was not sufficient to respect the compliance limit for ammonia nitroge...

Sociological survey in a municipality with a high level separate collection programme in an area of historic unpopularity

Behaviours, opinions and knowledge of citizens on MSW and separate collection were investigated in the city of Mercato San Severino (about 22,000 people), in the Campania region of Southern Italy that is an area suffering from a serious solid waste emergency that has lasted over 17 years due to the absence of treatment facilities. The image of heaps of rubbish in the streets of Naples and other nearby cities is only one side of the coin. Mercato San Severino has adopted an effective kerbside collection system since 2001 and a pay-as-you-throw program during 2005, guaranteeing more than the minimum level of recycling required by the Italian legislation. Structured questionnaires were administered to a sample of 500 people in 2010. Chi-square tests of independence were applied to state whether the differences were statistically significant (5%). About 90% of the sample stated that the success of the separate collection program was due to either the citizens and local authority or only the local authority, highlighting the leading role of the local authority and confirming that trust is the key to any social program success. The registered level of knowledge was better than that of nearby university students and citizens. The higher the education level, the greater the level of knowledge was.

Carbon and nitrogen removal from low-strength domestic wastewater with a two-stage submerged biological filter

The aim of the present study was to evaluate the secondary and tertiary treatment of low -strength domestic wastewater with submerged biological filters (BFs). The experiments were carried out with a two-stage pilot plant consisting of two subsequent filter columns. In the first aerated reactor, the removal of carbon and nitrification was accomplished (secondary nitrification); while, in the second anoxic reactor a post-denitrification process with methanol as external carbon source was performed. During the 3 months of experimental period, in average terms, Total Suspended Solids (TSS) concentrations of 156 mg/L were reduced to 5 mg/L; Chemical Oxygen Demand (COD) concentrations of 179 mg/L were reduced to 43 mg/L. In the secondary nitrification, mean influent NH4 + concentrations of 6.1 mg/L were reduced to average values of 1.8 mg/L. During the post-denitrification, mean influent NO3 − concentrations of 12.0 mg/L were reduced to average values of 6.1 mg/L. The overall process produced a backwashing effluent with an average concentration of about 175 mg/L of TSS.The aim of the present study was to evaluate the secondary and tertiary treatment of low -strength domestic wastewater with submerged biological filters (BFs). The experiments were carried out with a two-stage pilot plant consisting of two subsequent filter columns. In the first aerated reactor, the removal of carbon and nitrification was accomplished (secondary nitrification); while, in the second anoxic reactor a post-denitrification process with methanol as external carbon source was performed. During the 3 months of experimental period, in average terms, Total Suspended Solids (TSS) concentrations of 156 mg/L were reduced to 5 mg/L; Chemical Oxygen Demand (COD) concentrations of 179 mg/L were reduced to 43 mg/L. In the secondary nitrification, mean influent NH4 + concentrations of 6.1 mg/L were reduced to average values of 1.8 mg/L. During the post-denitrification, mean influent NO3 − concentrations of 12.0 mg/L were reduced to average values of 6.1 mg/L. The overall process produced a backwashing eff...

Combined Carbonaceous Removal and Nitrification with Biological Aerated Filters

Abstract This paper describes the use of a submerged biological aerated filter (BAFs), on a pilot plant scale, in the secondary nitrification of low strength domestic wastewater. The results, obtained throughout three months of tests, confirmed the ability of BAFs to obtain simultaneous carbonaceous removal and nitrification. In fact, after a start-up period of 5 weeks, a remarkable steady state condition in the removal of suspended solids (TSS), chemical oxygen demand (COD) and nitrification was reached. For a hydraulic loading rate of 1.6 m3 m−2 h−1, the mean efficiency of the process in the removal of TSS and COD was 85% and 83% respectively. Mean concentrations in the influent flow of around 114 mgTSS/L and 140 mgCOD/L were reduced to average values of below 17 mgTSS/L and 25 mgCOD/L. Secondary nitrification was achieved with a mean efficiency of 85% for a mean volumetric loads of 0.45 kgN-Namm m−3 d−1 (25°C). Through an intensive activity of nitrification, in the steady state condition, mean influent concentrations of around 12 mgN-Namm/L were reduced to average values of below 2 mgN-Namm/L. The removal loading rate increased linearly with the applied loading rate for volumetric loads of up to 0.7 kgN-Namm m−3 d−1. The nitrification was not sensitive to the applied COD loads because of the low level of carbon substrate.

Potential reuse of a leather tanning and an urban wastewater treatment plant effluent in Italy

This study aimed to evaluate the potential reuse of a leather tanning district and an urban wastewater treatment plant (UWWTP) effluents. The UWWTP discharges into the Sarno river which is one of the most polluted river in Europe. A water restoration program covering the rationalisation of the water use between industry and irrigation is in progress for this river. However, no use for fire protection which gains the most importance in summer season in the river catchement area as well as in all over Italy, was considered. The evaluation of potential reuse in this study included industrial reuse and storage for fire protection. Chlorine is suggested as disinfectant before fire protection use while UV is for the non-contact industrial use. The existing water reuse limits in Italy are discussed. Finally, the establishment of compliance limits for each reuse alternative is emphasised.

Removal of Trace Pollutants from Wastewater in Constructed Wetlands

The first experiments using constructed wetland for wastewater treatment were carried out in Germany in the early 1950s. Since then, their potential for removal conventional contaminants from wastewater is well established, making of them a technology suitable to fulfill important remediation strategies. Furthermore recent studies assessed the ability of CWs to remove trace pollutants. This chapter focuses on the fate of trace pollutants in constructed wetlands and aims at improving their assessment in full-scale studies. The removal of some categories of trace contaminant of worldwide relevance, classified as endocrine disruptors compound (EDCs) as well as pharmaceuticals and personal care products (PPCPs), has been reviewed together with mechanisms associated to their removal.

Chemically Assisted Primary Sedimentation: A Green Chemistry Option

Chemically Assisted Primary Sedimentation (CAPS) consists of adding chemicals in order to increase the coagulation, flocculation and sedimentation of raw urban wastewater. The CAPS process can be developed in order to increase the efficacy of primary sedimentation as well as avoid any interference with biological treatment processes. The application of CAPS is particularly suitable as a technique for the upgrading of urban wastewater treatment plants (UWWTPs). In fact, CAPS does not require any further significant structural intervention (so saving investment costs and territory portions). The aim of this contribution is to emphasise the role of CAPS as a green chemistry option available in a UWWTP. In particular, a specific aim of the chapter is to focus the attention on the energetic importance of CAPS due to its capacity to increase the production of the primary sludge and consequently the energy production with an anaerobic digestion treating separately primary and secondary sludge. The energetic convenience and “green” propensity of the application of CAPS is discussed by means of the presentation of a paradigmatic case study containing economic evaluations, as well.