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Semi-continuous biological hydrogen production through anaerobic digestion of mixture of waste by anaerobic digestion of mixture of waste with specified average residence time, and feeding equivalent volume of fresh mixture into reactor
No full textNOVELTY - Semi-continuous biological hydrogen production includes anaerobic digestion of mixture of waste in a hydrogen production reactor with an average residence time of the mixture in the hydrogen production reactor of 2-4 days, obtained through daily removal of a portion corresponding volume of mixture in the reactor; and feeding an equivalent volume of analogous fresh mixture into the reactor.
USE - Method for semi-continuous biological hydrogen production (claimed).
ADVANTAGE - The method can produce high quantities of hydrogen, with constant production of the element in time, which can be integrated with other processes for biochemical transformation of organic waste to provide a process whose end products are all useful and re-usable.
DETAILED DESCRIPTION - Semi-continuous biological hydrogen production comprises anaerobic digestion at 30-40 degrees C of a mixture of waste having not greater than 10 wt.% solids, containing biodegradable organic fractions of urban waste, both from separate refuse collection and from mechanical sorting, by vegetation waters deriving from olive oil production and by active sludge from urban sewage purification. The method is conducted with an average residence time of the mixture in the hydrogen production reactor of 2-4 days, obtained through daily removal of a portion corresponding to approximately 1/n of the volume of mixture in the reactor, where n indicates the number of days of desired average residence time, and feeding an equivalent volume of analogous fresh mixture into the reactor. INDEPENDENT CLAIMS are included for:
(1) anaerobic hydrogen production reactor (13) of the continuous stirred-tank type, equipped with inlet port(s) and outlet port(s), both gas-tight, with instruments to control pH and temperature of the reaction mixture present in the reactor, and with gas-tight ports to take samples of gas or reaction mixture; and
(2) a plant (10) for the combined production of hydrogen and methane, constituted by the reactor and a second gas-tight reactor (14) for methane production, connected in series by gas-tight ports and feed systems, so that an outlet port of the hydrogen production reactor is connected to an inlet port of the second reactor
Bonifica di mezzi porosi contaminati da metalli pesanti mediante elettrocinesi. Applicazione al trattamento di sedimenti marini
No full textDynamic transformations of nitrogen during mechanical-biological pre-treatment of municipal solid waste
No full textMechanical–biological pre-treatment (MBP) of municipal solid waste (MSW) has gained evidence as a practice capable of accomplishing
the requirements for environmental sustainable landfilling. In particular, MBP is effective in reducing the ammoniacal nitrogen
content in the leachate. However, few data are available on the modifications of the nitrogen forms occurring during MBP and on the
role played by processes such as nitrification and generation of refractory organic compounds. The dynamic transformations of nitrogen
were investigated during the MBP. MSW was mechanically and biologically pre-treated; samples were collected at different stages of the
process and analysed to investigate the evolution of nitrogen forms; batch and column leaching tests were performed as well. The results
indicate that nitrification is negligible and volatilization can only partially explain the low ammoniacal nitrogen content in the leachate.
Incorporation of ammoniacal nitrogen into a refractory organic form was assessed and is likely to play an important role. The maximum
content of refractory organic nitrogen in the solid waste was achieved after about 60 days of aerobic pre-treatment; therefore, the minimal
duration of the MBP should be about 8–9 weeks in order to optimize the ammoniacal nitrogen incorporation, unless the waste is
characterized by a low C/N ratio
Contaminazione ed Estrazione Mediante Ultrasuoni e Microonde del Fenantrene in Sedimenti Marini per lo Studio del Risanamento con Elettrocinesi
No full textEffects of separate collection efficiency on the costs of the MSW management system. A case study
No full textLow-power sonication for enhancing food waste hydrolysis in view of hydrogen bio-production
No full textEstrazione sequenziale ed estrazin con EDTA applicata a sedimenti portuali contaminati da metalli pesanti
No full textUna barriera elettrocinetica per il contenimento della dispersione di contaminanti. Studi preliminari
No full textPossible role of MSW anaerobic digestion in an integrated waste-water and municipal solid waste management cycle
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