Microalgae production in fresh market wastewater and its utilization as a protein substitute in formulated fish feed for oreochromis spp.

Rapid growing of human population has led to increasing demand of aquaculture production. Oreochromis niloticus or known as tilapia is one of the most globally cultured freshwater fish due to its great adaptation towards extreme environment. Besides, farming of tilapia not only involves small scales farming for local consumption but also larger scales for international market which contributes to a foreign currency earning. Extensive use of fishmeal as feed for fish and for other animals indirectly caused an increasing depletion of the natural resource and may consequently cause economic and environmental unstable. Microalgae biomass seems to be a promising feedstock in aquaculture industry. It can be used for many purposes such as live food for fish larvae and dried microalgae to substitute protein material in fish feed. The microalgae replacement in fish feed formulation as protein alternative seem potentially beneficial for long term aqua-business sustainability. The present chapter discussed the potential of microalgae as an alternative nutrition in fish feed formulations, specifically Tilapia

Continuous cultivation of photosynthetic microorganisms: approaches, applications and future trends

The possibility of using photosynthetic microorganisms, such as cyanobacteria and microalgae, for converting light and carbon dioxide into valuable biochemical products has raised the need for new cost-efficient processes ensuring a constant product quality. Food, feed, biofuels, cosmetics and pharmaceutics are among the sectors that can profit from the application of photosynthetic microorganisms. Biomass growth in a photobioreactor is a complex process influenced by multiple parameters, such as photosynthetic light capture and attenuation, nutrient uptake, photobioreactor hydrodynamics and gas-liquid mass transfer. In order to optimize productivity while keeping a standard product quality, a permanent control of the main cultivation parameters is necessary, where the continuous cultivation has shown to be the best option. However it is of utmost importance to recognize the singularity of continuous cultivation of cyanobacteria and microalgae due to their dependence on light availability and intensity. In this sense, this review provides comprehensive information on recent breakthroughs and possible future trends regarding technological and process improvements in continuous cultivation systems of microalgae and cyanobacteria, that will directly affect cost-effectiveness and product quality standardization. An overview of the various applications, techniques and equipment (with special emphasis on photobioreactors) in continuous cultivation of microalgae and cyanobacteria are presented. Additionally, mathematical modelling, feasibility, economics as well as the applicability of continuous cultivation into large-scale operation, are discussed.This research work was supported by the grant SFRH/BPD/98694/2013 (Bruno Fernandes) from Fundacao para a Ciencia e a Tecnologia (Portugal). The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013. The authors also thank the Project "BioInd Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028" Co-funded by the Programa Operacional Regional do Norte (ON.2-O Novo Norte), QREN, FEDE

Rapport V. 2 Les contributions d'Électricité de France à la valorisation des rejets thermiques

Contributions of Electricité de France to thermal discharge valorization. Contributions of Electricité de France to thermal discharge valorization consist both in elaborating technologies and in transmitting them to professionals. According to those purposes, some experimental operations have been conducted since 1974 on four sites of thermal power stations, both nuclear ant fossil fueled, cooled on sea shore or on river. In this last case, thermal discharge of both once-through and recirculating cooling systems, which present different caracteristics, have been separately evaluated Experimental programs and use of information gathered are under the responsability of associations where concerned professions, technical institutes and Administration are represented. Satisfactory experimental results, increasing participation of professional organizations and full scale operations planned around Dampierre power station make a favorable issue possible in a near future. This trend allows Electricité de France to foresee a gradual decrease of its contributions, in accordance with conditions to be examined.Electricité de France contribue à la valorisation des effluents thermiques de ses centrales en agriculture et aquaculture, tant dans la mise au point des techniques que dans le transfert des résultats aux professions intéressées. Dans ce but, des opérations d'essai et de démonstration ont été conduites depuis 1974 sur quatre sites de centrales thermiques, nucléaires et au fuel, réfrigérées en bord de mer ou sur rivière. Dans ce dernier cas, les effluents thermiques résultant de la réfrigération en circuits ouverts et fermés, qui présentent des caractéristiques différentes, on fait l'objet d'évaluations distinctes. La conduite de ces essais et l'utilisation des enseignements qu'ils ont permis de dégager ont été confiées à des associations où sont représentées les professions intéressées, les instituts techniques compétents, et l'Administration. Le déroulement satisfaisant de certaines opérations, la participation plus active des organisations professionnelles et le lancement prochain d'exploitations en vraie grandeur autour du site de Dampierre, laissent à penser que ces efforts devraient aboutir à terme. Cette perspective permet d'envisager une diminution progressive de l'aide de cet établissement selon des modalités qui sont examinées.Muller-Feuga A. Rapport V. 2 Les contributions d'Électricité de France à la valorisation des rejets thermiques. In: Rejets de chaleur à l'atmosphère. Gestion des calories et hydraulique associée. Compte-rendu des XVIes journées de l'hydraulique. Paris, 16-18 septembre 1980. Tome 2, 1980

Influence de la température et du poids unitaire sur la demande en oxygène de la truite arc-en-ciel (Salmo gairdnerii R.) en eau douce

Multiple correlation analysis is applied to a series of oxygen demand measurements on rainbow trout. It confirms that temperature and fish size are determining factors in standard feeding conditions. Two types of oxygen demand adjustment have been tested in relation with these two parameters. The final choice was an exponential law for temperature influence, which allows the introduction of the Q-10 concept. Its value is halved passing from a temperature below 10°C to a temperature above 12 C

The influence of temperature and wet weight on the oxygen demand of rainbow trout (Salmo gairdneri R.) in fresh-water

Multiple regression analysis was applied to a series of oxygen demand measurements on rainbow trout. It confirmed the determinant influence of temperature and size of fish under standard feeding conditions. Two types of adjustment of oxygen demand in relation to those two factors were tested, and one of them was choosen in which the temperature is under an exponential form. This allows the introduction of the Q10 concept. The value of Q10 is 3.5 when the water temperature is below 10°C and 1.7 above 12° C.L'analyse des corrélations multiples appliquée à une série de mesures de la demande en oxygène chez la truite arc-en-ciel confirme le caractère déterminant de la température et de la taille des poissons dans les conditions standard d'alimentation. Deux types d'ajustement de la demande en oxygène en fonction de ces deux paramètres sont étudiés. L'un d'entre eux est retenu. Il fait intervenir la température sous une forme exponentielle et permet d'introduire la notion de Q10. Celui-ci diffère d'un facteur 2 selon que la température est inférieure à 10° C ou supérieure à 12° C

Appraisal of a horizontal two-phase flow photobioreactor for industrial production of delicate microalgae species

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