An integrated Water Curtain-Microalgal Culture system (WCMC) to mitigate air emissions and recover nutrients from animal feeding operations

Abstract

Economically and technologically feasible air emission mitigation technologies are in high demand to sustain future animal agriculture. In this study, we designed an integrated Water Curtain-Microalgal Culture (WCMC) system to mitigate air emissions and recover nutrients to culture microalgae from Animal Feeding Operations (AFOs). The WCMC system included a water curtain, a windbreak wall and a raceway pond bioreactor. The water curtain was formed by continuously pumping water into a perforated water tank that flowed into the raceway pond bioreactor. The exhaust pollutants (NH 3 and particulate matter-PM) from a poultry house were dissolved and absorbed by the water droplets. Microalgal species were collected from local ponds and went through natural selection. Desmodesmus (R. Chodata) showed the best tolerances of temperature, nutrients, pH, and circulation shear force. The microalgal culture in the bioreactor was run in batch mode and the average productivity was 12.7 ± 2.9 g/m 2 /day. Exhaust ammonia (NH 3) and total suspended particle (TSP) concentrations were reduced by 74.9% and 89.2%, respectively. The harvested microalgal biomass had a protein content of 41.3%. The amino acid profile of microalgae demonstrated comparable quality to the WHO/FAO reference. Omega-3 fatty acids accounted for about 23% of total fat acids. Heavy metals (Pb, Cu,

Filamentous cyanobacteria triples oil production in seawater-based medium supplemented with industrial waste: monosodium glutamate residue

“…In large-scale production, areal and/or volumetric productivity are the main parameters to consider for space and cost efficiency [ 23 , 24 ]. These biomass and lipid productivities of different medium volumes are shown in Fig.…”

Maximum CO2 Utilization by Nutritious Microalgae

“…11−18 These members of the family Scenedesmaceae have demonstrated a tolerance for range of pH, temperature, nutrient variation, and shear force. 17 However, there are still significant barriers to growing nutritious salable microalgae, recovering nutrients from wastewater, and fixing CO 2 from flue gas in full-scale operations. 19 Currently, it is generally assumed that nutritious microalgae, including Scenedesmus obliquus, are inhibited by CO 2 levels characteristic of flue gas.…”

“…High-protein microalgae are a promising alternative to soy for more rapidly and sustainably produced protein-rich animal feed . Two members of the family of green algae, Desmodesmus and Scenedesmus, have been researched as candidates for nutritious microbial protein because of characteristic high-protein contents and favorable amino acid profiles. − These members of the family Scenedesmaceae have demonstrated a tolerance for range of pH, temperature, nutrient variation, and shear force . However, there are still significant barriers to growing nutritious salable microalgae, recovering nutrients from wastewater, and fixing CO 2 from flue gas in full-scale operations .…”