Search results for "WASTE TREATMENT"
showing 10 items of 72 documents
Effects of temperature on post-methanation of digested dairy cow manure in a farm-scale biogas production system.
2003
A post-methanation process that could be adopted at farm-scale, operating at temperatures prevailing in farm manure digester post-storage tanks, was evaluated. Digested manure samples from a farm digester (35 degrees C) and post-storage tank (5-10 degrees C) were incubated in parallel batches at 5-20 degrees C and as reference at 35 and 55 degrees C. Specific methane yields (kg(-1) volatile solids (VS)(added waste)) were 0.20-0.26 m3 at 35-55 degrees C and 0.085-0.09 m3 at 10-20 degrees C for digester material (345 days of incubation) and 0.16-0.21 m3 at 35-55 degrees C, 0.053-0.087 kg(-1) VS(added waste) m3 at 15-20 degrees C and 0.026 m3 at 10 degrees C for post-storage tank material (250…
Modelling the energy costs of the wastewater treatment process: The influence of the aging factor.
2017
Wastewater treatment plants (WWTPs) are aging and its effects on the process are more evident as time goes by. Due to the deterioration of the facilities, the efficiency of the treatment process decreases gradually. Within this framework, this paper proves the increase in the energy consumption of the WWTPs with time, and finds differences among facilities size. Accordingly, the paper aims to develop a dynamic energy cost function capable of predicting the energy cost of the process in the future. The time variable is used to introduce the aging effects on the energy cost estimation in order to increase the accuracy of the estimation. For this purpose, the evolution of energy costs will be …
Municipal waste management in Sicily: practices and challenges.
2006
There are numerous problems yet to be solved in waste management and although efforts towards waste recovery and recycling have been made, landfills are still the most common method used in the EU and many other industrialised countries. Thermal disposal, particularly incineration, is a tested and viable alternative. In 2004, only 11% of the annual waste production of Italy was incinerated. Sicily, with over five million inhabitants, is the second largest region in Italy where waste management is now a critical problem. The use of landfills can no longer be considered a satisfactory environmental solution; therefore, new methods have to be chosen and waste-toenergy plants could provide an a…
Cost modeling for sludge and waste management from wastewater treatment plants: an empirical approach for Spain
2013
Abstract Wastewater treatment involves the generation of large volumes of sludge and other waste. Managing this waste in an economical and environmentally acceptable way has become a matter of increasing importance over the last few years. While the technologies and processes to reduce sludge generation are being widely studied, research on the economic aspects is much more limited. This study applies a cost-modeling methodology that uses statistical information from a sample of Spanish wastewater treatment plants (WWTPs) to generate a sewage sludge and waste management cost function with the aim of contributing to a better understanding of the cost structure and predicting the cost savings…
Hybrid moving bed biofilm reactors: an effective solution for upgrading a large wastewater treatment plant
2009
Over the last few years there has been a growing attention regarding the receiving water body quality state. As a matter of a fact, the Directive 91/271 of the European Union (EU) replaced the “emission standard” concept that fixes discharge limits depending on polluting emission characteristics, with the “stream standard” concept that fixes discharge limits for each polluting substance depending on self-depurative characteristics of the RWB. In this context, several WWTPs need to be upgraded in order to meet stricter effluent limits. The need of WWTP upgrading was also emphasized by the growing urbanization that have led, in most cases, to get overloaded WWTP due to an overcoming of the ma…
Performance of a pilot-scale biotrickling filter in controlling the volatile organic compound emissions in a furniture manufacturing facility.
2009
A 0.75-m3 pilot-scale biotrickling filter was run for over 1 yr in a Spanish furniture company to evaluate its performance in the removal of volatile organic compounds (VOCs) contained in the emission of two different paint spray booths. The first one was an open front booth used to manually paint furniture, and the second focus was an automatically operated closed booth operated to paint pieces of furniture. In both cases, the VOC emissions were very irregular, with rapid and extreme fluctuations. The pilot plant was operated at an empty bed residence time (EBRT) ranging from 10 to 40 sec, and good removal efficiencies of VOCs were usually obtained. When a buffering activated carbon prefil…
Anaerobic digestion of organic solid poultry slaughterhouse waste – a review
2002
This work reviews the potential of anaerobic digestion for material recovery and energy production from poultry slaughtering by-products and wastes. First, we describe and quantify organic solid by-products and wastes produced in poultry farming and poultry slaughterhouses and discuss their recovery and disposal options. Then we review certain fundamental aspects of anaerobic digestion considered important for the digestion of solid slaughterhouse wastes. Finally, we present an overview of the future potential and current experience of the anaerobic digestion treatment of these materials.
A data-driven methodology to support pump performance analysis and energy efficiency optimization in Waste Water Treatment Plants
2017
Abstract Studies and publications from the past ten years demonstrate that generally the energy efficiency of Waste Water Treatment Plants (WWTPs) is unsatisfactory. In this domain, efficient pump energy management can generate economic and environmental benefits. Although the availability of on-line sensors can provide high-frequency information about pump systems, at best, energy assessment is carried out a few times a year using aggregated data. Consequently, pump inefficiencies are normally detected late and the comprehension of pump system dynamics is often not satisfactory. In this paper, a data-driven methodology to support the daily energy decision-making is presented. This innovati…
Quantification of kinetic parameters for heterotrophic bacteria via respirometry in a hybrid reactor
2010
Over the last decade new technologies are emerging even more for wastewater treatment. Among the new technologies, a recent possible solution regards Moving Bed Biofilm Reactors (MBBRs) that represent an effective alternative to conventional processes. More specifically such systems consist in the introduction of plastic elements inside the aerobic reactor as carrier material for the growth of attached biomass. Recently, one of the mostly used alternatives is to couple the Moving Bed Biofilm Reactor (MBBR) process with the conventional activated sludge process, and the resulting process is usually called HMBBR (Hybrid MBBR). In the MBBR process the biofilm grows attached on small plastic el…
Stabilisation of MSWI bottom ash with sulphide-rich anaerobic effluent.
2007
Effluent of an anaerobic sulphate-reducing wastewater treatment process was used to stabilise bottom ash. The effect of stabilisation on the concentration and binding of Ca, P, S, Cu, Pb, Zn, As, Cr, and Mo were studied by comparing results of sequential extraction from fresh and stabilised bottom ash. The stabilisation treatment improved the retention of Ca, Cu, Pb, S, and Zn in bottom ash compared to a treatment with ion-exchanged water. In addition to retention, Cu, S, and Zn were accumulated from the anaerobic effluent in the bottom ash. Concentrations of As, Cr, and Mo remained on the same level, whereas leaching of P increased compared to control treatment with ion-exchanged water. Im…