The aim of this work was to study the possible deactivation effects of biogas trace ammonia concentrations on methanation catalysts. It was found that small amounts of ammonia led to a slight decrease in the catalyst activity. A decrease in the catalyst deactivation by carbon formation was also observed, with ammonia absorbed on the active catalyst sites. This was via a suppression of the carbo...

La/Fe/TiO₂ composite photocatalysts were synthesized by Sol-Gel method and well characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen-physical adsorption, and UV-Vis diffuse reflectance spectra (UV-Vis DRS). It is interesting that the doped catalysts were in anatase phase while the pure TiO₂ was in rutile phase. In addition, the composites possessed bette...

In this work modelling and experimental validation of an integrated process for the removal of carbon dioxide from ammonia solutions is presented (decarbonisation). In this process, carbon dioxide is stripped out from the solution simultaneously with small amounts of ammonia at ambient pressure in a packed column. Recovery of the stripped ammonia can be reached by combining absorption of ammoni...

A dynamic model to describe ammonia removal in a gas-phase biofilter was developed. The mathematical model is based on discretized mass balances and detailed nitrification kinetics that include inhibitory effects caused by free ammonia (FA) and free nitrous acid (FNA). The m I a s ©

Odour from agricultural activities, such as the spreading of manure and the housing of animals, is increasingly being considered a nuisance in densely populated countries like the Netherlands. The objective of this research was to study the odour removal from pig house exhaust air by a biotrickling filter that had been implemented for ammonia abatement. At a regular pig production farm, the per...

The purpose of this research was to neutralize livestock-generated ammonia by using biofilters packed with inexpensive inorganic and organic packing material combined with multicultural microbial load at typical ambient temperatures. Peat and inorganic supporting materials were used as biofiltration matrix packed in a perfusion column through which gas was transfused. Results show the ammonia r...

In the paper, control possibilities for the nitrogen removal process within activated sludge wastewater treatment plants are discussed. A predictive controller is introduced which aims to reduce the peaks in effluent concentration for ammonia nitrogen. Additionally, the controller improves the overall nitrogen removal using less aeration energy. A parsimonious deterministic model is used for th...

Currently, energy and environmental efficiency are critical aspects in wastewater treatment plants (WWTPs). In fact, WWTPs are significant energy consumers, especially in the active sludge process (ASP) for the N-ammonia removal. In this paper, we face the challenge of simultaneously improving the economic and environmental performance by using a reinforcement learning approach. This approach i...

Glycine is an important ammoniagenic amino acid, which is increased in acute liver failure (ALF). We have previously shown that L-ornithine phenylacetate (OP) attenuates ammonia rise and intracranial pressure in pigs suffering from ALF but failed to demonstrate a stoichiometric relationship between change in plasma ammonia levels and excretion of phenylacetylglutamine in urine. The aim was to i...

BACKGROUND/AIMS It has been proposed that, in acute liver failure, skeletal muscle adapts to become the principle organ responsible for removal of blood-borne ammonia by increasing glutamine synthesis, a reaction that is catalyzed by the cytosolic ATP-dependent enzyme glutamine synthetase. To address this issue, glutamine synthetase expression and activities were measured in skeletal muscle of ...