Zeolites in complex nitrogen biofertilizers

Handbook of Microalgae-Based Processes and Products

Gouveia

2020

Microalgae-based bioproducts remain expensive mainly due to microalgae cultivation, harvesting and downstream processing costs. Nonetheless, microalgae are a high potential source of several biofuels, biofertilizers, and bioproducts (e.g. carbohydrates, long-chain fatty acids, pigments and proteins), which can provide important nutritional, cosmetical, pharmaceutical and health benefits. In addition, they are able to perform wastewater bioremediation and carbon dioxide mitigation. This not only contributes to a more sustainable microalgae production, with environmental benefits, but offers cost savings on the whole process. Hence, from these small cellular factories, a large source of compounds and products can be obtained, providing a real microalgal-based biorefinery. This type of approach is crucial for the full application and commercialization of microalgae in a large range of products and industries, with added benefits for bio-economy and society in general.This chapter addresses the potential transformation of microalgal biomass into a wide range of marketable products, presenting examples of experimental microalgae-based biorefineries grown in an autotrophic mode at a laboratory scale.

Section: Microalgae-based Biofertilizersmentioning

confidence: 99%

Microalgal biorefineries

Handbook of Microalgae-Based Processes and Products

Gouveia

2020

“…In this respect, a 50:50 ratio of urea and zeolite is more efficient than a 70:30 ratio. Chakhalyan et al (2008) reported that the complex of zeolite nitrogen-fixing microorganisms exceeded the efficiency of the known bacterial nitrogen fertilizers and ecologically safe biofertilizers. The stimulating action of zeolites was observed upon the growth and propagation of Azotobacter chroococcum.…”

Section: Fabrication Of Intercalated/impregnated Fertilizersmentioning

confidence: 99%

Nano-nitrogen Formulations for Enhancing Use Efficiency: A Review

Manikandan¹,

Deshmukh²,

Subramainan³

et al. 2019

agroped

Commercial crop production has increased nitrogenous fertilizer consumption by two to three times. However, temporal changes and yield stagnation of major crops over three decades urge us to revisit the fertilizer use efficiency through nano-techniques with specific reference to nitrogen fertilizers. Although nanofertilizer technology is quite innovative, literature available in this field is very limited. In this review, literature pertaining to the losses of nitrogen (N) in agro-ecosystems, slow-release N fertilizers, nanofertilizer N formulations with synthesis, characterization and their application in agriculture and associated effects are elaborated. This review serves as a strong database to understand and gain insights into innovative nanotechnologies infusion with N fertilizers research and their benefits in agriculture. Nano fertilizers are capable of enhancing crop yield as well as nitrogen use efficiency (NUE) of crops and may be considered as one of the potential alternatives for soil fertility and plant nutrition for agricultural sustainability.

“…Thus chemical fertilizers have become a basic input in modern agriculture. The overdependence on synthetic agrochemicals has resulted in massive ecological degradation throughout the world, leading to ocean dead zones, eutrophication, soil infertility and biodiversity loss, damaging the biosphere and causing various human diseases through the consumption of contaminated food and water . In addition, the cost of production of chemical fertilizers is rising; hence a suitable alternative is urgent.…”

Section: Introductionmentioning

confidence: 99%

Scenedesmus obliquusmicroalga‐based biorefinery – from brewery effluent to bioactive compounds, biofuels and biofertilizers – aiming at a circular bioeconomy

Ribeiro

Biofuels Bioprod Bioref

et al. 2019

Self Cite

100

The circular bioeconomy concept relies on the exploitation of wastes as a feedstock of different biotechnological processes to obtain, as much as possible, a huge spectrum of biochemical components through a biorefinery platform. This work deals with the treatment of brewery effluent through the cultivation of Scenedesmus obliquus microalga and the use of the biomass in a complex biorefinery. The treatment proved efficient in the removal of nutrients (N, P and COD removals of 88, 30 and 71% respectively). Several compounds and products were obtained from the biomass, such as: (a) phenols (0.249-1.016 mg GAE mL −1 ) and flavonoids (0.05-0.167 mg CE mL −1 ) by subcritical water extraction (SWE) at 120 °C, the extraction efficiency being five times higher at 200 °C; (b) biohydrogen by dark fermentation (67.1 mL H 2 g VS −1 ); (c) bio-oil (64%), biochar (30%) and biogas (6%) by pyrolysis; and (d) enhanced capacity of germination/growth of wheat and barley seeds by S. obliquus culture and biomass (pellet, after centrifugation); better results were obtained with the biomass cultivated in brewery effluent (when compared with synthetic medium), and the biomass pellet was better than the whole culture; barley seeds 1170 A Ferreira et al.In the Field: Scenedesmus obliquus microalga-based biorefinery aiming at a circular bioeconomy treated with the pellet from the brewery effluent had the highest germination index (GI) of 85 compared with the control (tap water) GI of 35. The innovative study emphasis was on reducing microalgae production costs, providing environmental benefits in a biorefinery-based S. obliquus platform.