Laboratoire Of Biotechnologie Of Lenvironnement

Narbonne, France

Laboratoire Of Biotechnologie Of Lenvironnement

Narbonne, France
SEARCH FILTERS
Time filter
Source Type

Collet P.,French National Institute for Agricultural Research | Helias Arnaud A.,French National Institute for Agricultural Research | Helias Arnaud A.,Montpellier SupAgro | Lardon L.,French National Institute for Agricultural Research | And 3 more authors.
Bioresource Technology | Year: 2011

Due to resource depletion and climate change, lipid-based algal biofuel has been pointed out as an interesting alternative because of the high productivity of algae per hectare and per year and its ability to recycle CO2 from flue gas. Another option for taking advantage of the energy content of the microalgae is to directly carry out anaerobic digestion of raw algae in order to produce methane and recycle nutrients (N, P and K). In this study, a life-cycle assessment (LCA) of biogas production from the microalgae Chlorella vulgaris is performed and the results are compared to algal biodiesel and to first generation biodiesels. These results suggest that the impacts generated by the production of methane from microalgae are strongly correlated with the electric consumption. Progresses can be achieved by decreasing the mixing costs and circulation between different production steps, or by improving the efficiency of the anaerobic process under controlled conditions. This new bioenergy generating process strongly competes with others biofuel productions. © 2010 Elsevier Ltd.


Thalla A.K.,Indian Institute of Technology Roorkee | Chella D.,National Institute of Technology Raipur | Torrijos M.,Laboratoire Of Biotechnologie Of Lenvironnement
Journal of Hazardous, Toxic, and Radioactive Waste | Year: 2012

Experimental studies were conducted on a 5-L laboratory-scale activated sludge-biofilm reactor in two phases: phase I with 30% filling (Bioflow 9) and Phase II with 60% filling [Biofilm 9 (30%), Flocor (15%), and BioBall (15%)]. The substrate used in the study was prepared by diluting the vinasse with tap water and adding urea, KH 2PO 4 (source of nitrogen and phosphorous), and MgSO 4, resulting in a chemical oxygen demand (COD)/N/P ratio of 300/10/1.. At 30% Bioflow 9 filling, increasing the influent COD concentration [while maintainig the same hydraulic residence time (HRT)] reduced the efficiency of COD removal. At 60% filling, it was observed that increasing the feed composition while maintaining the same HRT reduced the percentage removal of COD and NH 4 +-N. The sludge concentration within the reactor slightly increased with increase in feed concentration and a stage is reached where the sludge settling in the settling tank was very poor while the yield of the sludge increased to its maximum. As the concentrations of COD and mixed liquor volatile suspended volatiles (MLVSS) decreased, the system returned to normal. In addition, hydrodynamic, particle size distribution, and single-strand conformation polymorphism (SSCP) studies were done on the system. Particle size distribution studies conducted at varying organic loading rates (OLRs) showed an increase in floc size, hindering the settleability of the sludge. Comparison of the SSCP results for fixed and suspended biomass revealed that a smaller number of species were present in suspended than in attached biomass. This finding was supported by quantitative biomass evaluations on media and in suspension. © 2012 American Society of Civil Engineers.


Gonzalez-Fernandez C.,Laboratoire Of Biotechnologie Of Lenvironnement | Sialve B.,Naskeo Environnement | Bernet N.,Laboratoire Of Biotechnologie Of Lenvironnement | Steyer J.-P.,Laboratoire Of Biotechnologie Of Lenvironnement
Biofuels, Bioproducts and Biorefining | Year: 2012

Among biofuel production processes using microalgal biomass, biogas generation seems to be the least complex. This review summarizes information regarding anaerobic digestion of different microalgae species. Various operational parameters and microalgae characteristics (macromolecular distribution and cell wall) are reviewed in the light of their effects on methane production. Additionally, the enhancement of methane production rates achievable by applying biomass pre-treatments and codigestion of substrates is also reported. The review finally covers the so-claimed similarities of microalgal biomass and activated sludge as a substrate for anaerobic digestion. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd.


Gonzalez-Fernandez C.,Laboratoire Of Biotechnologie Of Lenvironnement | Sialve B.,Naskeo Environnement | Bernet N.,Laboratoire Of Biotechnologie Of Lenvironnement | Steyer J.-P.,Laboratoire Of Biotechnologie Of Lenvironnement
Biofuels, Bioproducts and Biorefining | Year: 2012

Microalgae are now the focus of intensive research because of their potential as a renewable feedstock for biofuel production. This review briefly examines the effect of reactor design, nutrient, and light regimens on microalgae productivity and macromolecular composition. Downstream processing including common biofuel production as well as life cycle assessment and technoeconomical aspects are discussed. Even though algal biofuels are more environmentally friendly than fossil fuels, economical feasibility is a challenging issue. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd.


Uggetti E.,Laboratoire Of Biotechnologie Of Lenvironnement | Sialve B.,Laboratoire Of Biotechnologie Of Lenvironnement | Trably E.,Laboratoire Of Biotechnologie Of Lenvironnement | Steyer J.-P.,Laboratoire Of Biotechnologie Of Lenvironnement
Biofuels, Bioproducts and Biorefining | Year: 2014

In the energy and chemical sectors, alternative production chains should be considered in order to simultaneously reduce the dependence on oil and mitigate climate change. Biomass is probably the only viable alternative to fossil resources for production of liquid transportation fuels and chemicals since, besides fossils, it is one of the only available sources of carbon-rich material on Earth. Over recent years, interest in microalgae biomass has grown in both fundamental and applied research fields. The biorefinery concept includes different technologies able to convert biomass into added-value chemicals, products (food and feed) and biofuels (biodiesel, bioethanol, biohydrogen). As in oil refinery, a biorefinery aims at producing multiple products, maximizing the value derived from differences in biomass components, including microalgae. This paper provides an overview of the various microalgae-derived products, focusing on anaerobic digestion for conversion of microalgal biomass into methane. Special attention is paid to the range of possible inputs for anaerobic digestion (microalgal biomass and microalgal residue after lipid extraction) and the outputs resulting from the process (e.g. biogas and digestate). The strong interest in microalgae anaerobic digestion lies in its ability to mineralize microalgae containing organic nitrogen and phosphorus, resulting in a flux of ammonium and phosphate that can then be used as substrate for growing microalgae or that can be further processed to produce fertilizers. At present, anaerobic digestion outputs can provide nutrients, CO2 and water to cultivate microalgae, which in turn, are used as substrate for methane and fertilizer generation. © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd.


Langlois J.,Montpellier SupAgro | Sassi J.-F.,Center Detudes Et Of Valorisation Des Algues Ceva | Jard G.,Laboratoire Of Biotechnologie Of Lenvironnement | Steyer J.-P.,Laboratoire Of Biotechnologie Of Lenvironnement | And 3 more authors.
Biofuels, Bioproducts and Biorefining | Year: 2012

Algae are a promising source of industrial biomass for the future. In order to assess if aquacultured seaweed (macroalgae) could be considered an environmentally friendly source of biomass for bioenergy, life cycle assessments were performed for European countries, comparing methane as a biofuel from the anaerobic digestion (A) of whole seaweeds, (B) of alginate extraction residues, and (C) natural gas as a fossil fuel reference. These results clarify that the sources of electricity and energy used to heat the anaerobic digesters have an important impact. Recycling of materials and use of greenhouses at the nursery stage also allow environmental improvements for system (A). Ecodesign can make algal biomethane competitive in several categories compared to natural gas: a decrease of 21.9% and 54.2% in greenhouse gas (GHG) emissions and 58.6% and 68.7% in fossil depletion for systems (A) and (B), respectively, decrease in ozone depletion, and last but not least, improvement in the marine eutrophication index for system (A). For system (B), benefits are more arguable and dependent on the allocation. To conclude, seaweed could become competitive with terrestrial feedstock for biofuel production in the near future. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd.


PubMed | Laboratoire Of Biotechnologie Of Lenvironnement
Type: Journal Article | Journal: Water science and technology : a journal of the International Association on Water Pollution Research | Year: 2012

The purpose of this work was to investigate the effects of the addition of by-products from the refining of vegetable oil on the behavior of co-digestion reactors treating a mixture of grass, cow dung and fruit and vegetable waste. Three by-products were used: one soapstock, one used winterization earth and one skimming of aeroflotation of the effluents. Three 15 l reactors were run in parallel and fed five times a week. In a first phase of 4 weeks, the three reactors were fed with the co-digestion substrates alone (grass, cow dung and fruit and vegetable waste) at an organic loading rate (OLR) of 1.5 g VS/kg d (VS: volatile solids). Then, a different by-product from the refining of oil was added to the feed of each reactor at an OLR of 0.5 g VS/kg d, generating a 33% increase in the OLR. The results show that the addition of by-products from the refining of oil is an efficient way of increasing the methane production of co-digestion reactors thanks to high methane yield of such by-products (0.69-0.77 l CH(4)/g VS loaded). In fact, in this work, it was possible to raise the methane production of the reactors by about 60% through a 33% increase in the OLR thanks to the addition of the by-products from the refining of vegetable oil.

Loading Laboratoire Of Biotechnologie Of Lenvironnement collaborators
Loading Laboratoire Of Biotechnologie Of Lenvironnement collaborators