Biomedical subjects

C Collivignarelli

Publications and source records attributed to C Collivignarelli.

6 recordsLinked to original sources

PubMed2006

Process improvement and energy saving in a full scale wastewater treatment plant: air supply regulation by a fuzzy logic system.

Achieving good performance in air supply control is an important goal in the management of wastewater treatment plants, whose highly nonlinear behaviour makes the application of conventional control techniques problematic. This paper presents the development and experimentation of a fuzzy logic system for air supply regulation in a full scale municipal wastewater treatment plant. The system is composed of two main modules, one devoted to continuously adjusting the DO set point on the basis of the current effluent NH4(+)-N concentration (on-line measurement), and the other devoted to achieve the DO set point by controlling air supply devices. The experiment was carried out on the plant for about one year, leading to significant advantages in terms of both process stability and energy saving.

Air Movements↗

PubMed2004

AOPs with ozone and UV radiation in drinking water: contaminants removal and effects on disinfection byproducts formation.

In this study, the advanced oxidation with ozone and UV radiation (with two low pressure UV lamps, at 254 and 185 nm wavelength) were experimented on a surface water in order to study the removal of two odorous compounds (geosmin and 2-methylisoborneol) and a pesticide (metolachlor), the influence on organic compounds (UV absorbance and THM precursors) and bromate formation. Different batch tests were performed with ozone concentration up to 10 mg/L, UV dose up to 14,000 J/m2 and a maximum contact time of 10 minutes. The main results show that metolachlor can be efficiently removed with ozone alone while for geosmin and MIB a complete removal can be obtained with the advanced oxidation of ozone (with concentration of 1.5-3 mg/L and contact time of 2-3 minutes) with UV radiation (with doses of 5,000-6,000 J/m2). As concerns the influence on the organic precursors, all the experimented processes show a medium removal of about 20-40% for UV absorbance and 15-30% for THMFP (trihalomethanes formation potential). As concerns bromate formation, the advanced oxidation of ozone/UV 254 nm shows a bromate formation that is about 40% lower with respect to conventional oxidation with ozone.

Acetamides↗

PubMed2003

Field monitoring and evaluation of innovative solutions for cleaning storm water runoff.

Urbanization increases the variety and amount of pollutants transported to receiving waters. Sediment from development and new construction; oil, grease, and toxic chemicals from automobiles; nutrients and pesticides from turf management and gardening; viruses and bacteria from failing septic systems; road salts; and heavy metals are examples of pollutants generated in urban areas. Sediments and solids constitute the largest volume of pollutant loads to receiving waters in urban areas. When runoff enters storm drains, it carries many of these pollutants with it. In older cities, this polluted runoff is often released directly into open waterways without any treatment. Increased pollutant loads can harm fish and wildlife populations, kill native vegetation, foul drinking water supplies, and make recreational areas unsafe. The objective of the study, performed by University of Pavia (Italy), University of Brescia (Italy) and GreenTechTexas International (US), reported herein is to evaluate the use of an innovative stormwater technology (EcoDräin) to reduce pollution due to urban runoff in existing urban areas. The paper describes the methodology and the results achieved with tests conducted in laboratory in Pavia University in Italy and in two pilot areas in Italy and in Australia to investigate the EcoDräin's effectiveness for oil and heavy metals retention and sediment trapping. In the tests performed in a marina near Sydney in Australia a reduction has been achieved in oil and grease concentration higher than 95% and a reduction in metal concentration (particularly Copper, Lead and Zinc) close to 98%. The paper also describes the methodology of the analysis on the absorbing material after its use and the consequent determination of the most efficient and environmentally safe way to dispose of consummated absorbent.

Absorption↗

PubMed2002

A comparison among different methods for evaluating the biomass activity in activated sludge systems: preliminary results.

In order to improve activated sludge plant operation (achieving higher efficiency and cost savings) beside influent and effluent characteristics and working parameters (e.g. dissolved oxygen, total and volatile suspended solids, pH, recirculation flow rate, etc.), the biomass activity should be monitored, the bacteria being responsible for the pollutant degradation. Since conventional cultivation based methods are inadequate to quantify environmental microorganisms (due to scarce number of cultivable microorganisms and time-consuming procedures) several "non-conventional" techniques were applied in this study, in order to compare the obtainable information and their routine feasibility. Different measurements (VSS concentration, Oxygen Uptake Rate, microbial counts by cultural and biomolecular methods--MPN-PCR, ATP content, dehydrogenase activity, microbial cell viability and enzymatic activity) were carried out on mixed liquor samples, taken from a municipal activated sludge plant (440,000 p. e.). The preliminary results of the research are presented in this paper.

Adenosine Triphosphate↗

PubMed2001

Optimisation of industrial wastes reuse as construction materials.

This study concerns the reuse of two inorganic wastes, foundry residues and fly ashes from municipal solid waste incineration, as "recycled aggregate" in concrete production. This kind of reuse was optimised by waste treatment with the following steps: waste washing with water; waste stabilisation-solidification treatment with inorganic reagents; final grinding of the stabilised waste after curing for about 10-20 days. Both the treated wastes were reused in concrete production with different mix-designs. Concrete specimens were characterised by means of conventional physical-mechanical tests (compression, elasticity modulus, shrinkage) and different leaching tests. Experimental results showed that a good structural and environmental quality of "recycled concrete" is due both to a correct waste treatment and to a correct mix-design for concrete mixture.

Conservation of Natural Resources↗

PubMed2001

The role of chemical oxidation in combined chemical-physical and biological processes: experiences of industrial wastewater treatment.

In this work, some experiences are described concerning the application of chemical oxidation in the treatment of industrial wastewaters in combination with other chemical-physical and/or biological processes. In the first case, two different wastewaters from saturated and unsaturated polyester resin production were considered. In a second case, optimal process conditions were assessed for the treatment of a wastewater deriving from polystyrene production. A third experience dealt with a comparison among different processes (flocculation, Fenton process, ozonisation, oxidation by means of ozone and hydrogen peroxide, oxidation by means of hydrogen peroxide and UV radiation), for the pretreatment of two industrial wastewaters (the first one being produced in a textile factory, the second one coming from detergent manufacturing). The evaluation of different processes was carried out by means of laboratory scale tests, considering treatment efficiency (organic substance removal, changes in wastewater biodegradability) and parameters (chemicals and energy consumption, sludge production) which play an important role in cost determination.

Biodegradation, Environmental↗