Decision document on the revision of the VERA protocol on air cleaning technologies March

In the project “ICT-AGRI: Development of harmonized sampling and measurement methods for odour, ammonia and dust emissions” different subgroups have been formed focusing on either ammonia, odour or dust. In this report, the conclusions of the ammonia subgroup regarding harmonization of measurement methods for the estimation of the ammonia removal from air cleaning technologies are summarized

A General Approach for Predicting the Filtration of Soft and Permeable Colloids: The Milk Example

Membrane filtration operations (ultra-, microfiltration) are now extensively used for concentrating or separating an ever-growing variety of colloidal dispersions. However, the phenomena that determine the efficiency of these operations are not yet fully understood. This is especially the case when dealing with colloids that are soft, deformable, and permeable. In this paper, we propose a methodology for building a model that is able to predict the performance (flux, concentration profiles) of the filtration of such objects in relation with the operating conditions. This is done by focusing on the case of milk filtration, all experiments being performed with dispersions of milk casein micelles, which are sort of ″natural″ colloidal microgels. Using this example, we develop the general idea that a filtration model can always be built for a given colloidal dispersion as long as this dispersion has been characterized in terms of osmotic pressure Π and hydraulic permeability k. For soft and permeable colloids, the major issue is that the permeability k cannot be assessed in a trivial way like in the case for hard-sphere colloids. To get around this difficulty, we follow two distinct approaches to actually measure k: a direct approach, involving osmotic stress experiments, and a reverse-calculation approach, that consists of estimating k through well-controlled filtration experiments. The resulting filtration model is then validated against experimental measurements obtained from combined milk filtration/SAXS experiments. We also give precise examples of how the model can be used, as well as a brief discussion on the possible universality of the approach presented here

L'Analyse de cycle de vie et l' éco-conception au service de l'amélioration des performances environnementales des procédés

D’après l’étude EIPRO - Environmental Impact of PROducts (Tukker A. et al., 2006), réalisée dans le cadre de la Politique Intégrée des Produits (Commission Européenne, 2006), l’alimentation et les boissons contribuent significativement à l’impact environnemental généré par la consommation des européens (de 20 à 30%) ; la viande et les produits carnés, puis dans une moindre mesure les produits laitiers, étant les principaux contributeurs. La charge environnementale des produits alimentaires d’origine animale est principalement associée à leur production agricole (Foster C. et al., 2006) ; il est cependant intéressant de souligner qu’il existe des leviers d’amélioration environnementale à chaque étape du cycle de vie des produits alimentaires, y compris lors de leur transformation (Roy et al., 2009). A ce titre, comme l’explique Jungbluth (2000), l’industrie agroalimentaire peut directement agir sur trois niveaux de prise de décision environnementale, dont la transformation. L’étude IMPRO-meat & dairies - environmental IMprovement of PROducts (Weidema B. P. et al., 2008), réalisée en complément de l’étude EIPRO, va également dans ce sens. Parmi les voies qu'elle propose pour améliorer les performances environnementales de la viande et des produits laitiers, elle recommande de réduire les consommations énergétiques à chaque étape du cycle de vie de ces produits, y compris lors de leur transformation industrielle. L’objectif de cet article est de présenter les deux grandes étapes d’une démarche visant à améliorer les performances environnementales d’un procédé : 1- L’évaluation environnementale du procédé ; 2- L’éco-conception du procédé intégrant les leviers d’amélioration environnementale identifiés lors de l’évaluation. Cette présentation sera illustrée par la retranscription des travaux réalisés dans le cadre du projet de recherche ECOPROM

Farm-Scale Applicability of Three Covers (Peat, Polystyrene Balls and Synthetic Sheet Roof) to Reduce Ammonia Emissions from Pig Slurry Storage

International audienceCovering the slurry pit has been shown to be one of the best ways to reduce ammonia emissions (NH3) during manure management. Yet, few studies have been conducted at farm scale. We studied the feasibility of three cover materials (peat, polystyrene balls and synthetic sheet roof) to reduce ammonia (NH3) emissions during on-farm storage of pig slurry. The impact on greenhouse gasemissions, methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2) of covering the slurry pit was also evaluated. Simultaneous field experiments were carried out using two similar pits at a farm with peat and polystyrene ball covers, which allowed direct comparison of the feasibility ofthe two covers to reduce gas emissions (measured using the dynamic chamber technique). Emissions from the third option (using a synthetic sheet roof) were estimated by measuring the concentrations in the headspace under the cover and the air leakage from the cover with a tracer gas(CO2). Results showed that the polystyrene balls cover reduced emissions of NH3 during storage by up to 80% whatever the season, but increased potential greenhouse gas emissions by 20% in summer. No consistent reduction was achieved with the peat cover even though some individual results seemed to indicate up to 25% reduction in ammonia emissions; moreover, there was a 30%increase in CH4 and CO2 emissions during the storage period. The use of a synthetic sheet roof enabledup to 90% reduction in NH3, CH4 and CO2 emissions whatever the season

Assessment and comparison of annual gaseous emissions of three biological treatments of pig slurry with a storage-spreading system

Field measurements of ammonia (NH3), nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) were carried out from biological aerobic treatment plants installed in Brittany (Western France). Three biological aerobic reactors and four treatment by-product storages were studied. The field results showed that the emissions of CH4, CO2 and NH3 were more important for the non-aerated effluents (raw slurry and separated solid fraction), which have higher ammonium and organic matter levels than treatment by-products. N2O was only detected from biological reactor and was lower than 1% of total nitrogen entering treatment plant. The assessment and calculation of annual gaseous flux based on these field results and an estimation of raw slurry, matter flows and gaseous emissions for each module of the treatment was done for 4 slurry management schemes for a farrowing-fattening farm with 200 sows. In all cases, the environmental assessment shows a decrease of the greenhouse gases and NH3 by using a biological treatment compared to a traditional manure management based on 6 months storage before spreading. The reduction is 30-50% to 68 % of NH3 when the plant is or not set up with a mechanical separation device. Greenhouse gases are reduced by about 55% whatever the biological treatment plant