Application of microalgae and wastewater as plant nutrients and stimulants in hydroponic technology

Publication Type:
Issue Date:
Full metadata record
Nitrous oxide is 300 times stronger than carbon dioxide in causing climate change, and 80% of global nitrous oxide is from nitrogen fertilisers used in soil-based agriculture. Finding ways to minimise the carbon footprint related to the production of nitrogen-based agricultural fertiliser, and reusing waste nutrients from wastewater, will benefit parallelly in saving the energy expenses of wastewater treatment and in producing fertilisers. This research proposes utilising high concentration wastewater, such as desalination brine, blended with low concentration wastewater (for example, secondary treated domestic wastewater) in the optimal proportion to produce microalgae growth media. Growing nitrogen-fixing microalgae in blended wastewater yields a dual solution for wastewater nutrient recovery and obtaining biologically fixed nitrogen. The nitrogen produced by the algae is a usable form of plant nutrient. Microalgae are known to produce plant hormones; the acid-digested algal biomass can be used as a source of nutrients and plant stimulants to grow plants in hydroponics. Growing plants in hydroponics minimise nitrogen nutrient loss (as in soil-based agriculture) and nitrous oxide evolution. This study used non-hazardous wastewaters for producing microalgae biomass using blends of high and low-concentration wastewaters and assessed its nutrient recovery rates. Applied microalgal biomass extract as a source of nitrogen and whole nutrients to grow plants in hydroponics and added effort to profile the plant hormones in the algal biomass. The aims of this research focused on (i) using different wastewater nutrient concentrations as a source to attain an optimal microalgal growth media for biomass production and nutrient recovery from wastewater; (ii) comparing the efficacy of microalgal biomass extract based hydroponic nutrients with other commercial hydroponic nutrients. Consequently, the objective are (1) to develop a wastewater blending method for microalgal cultivation and nutrient recovery, (2) to examine the feasibility of producing hydroponic nutrients and stimulants from microalgal biomass, (3) to compare the growth efficiency of food crops in microalgal extracts nutrients and other available hydroponic-nutrients. The comparative study of microalgal biomass extract-based hydroponic nutrients with other commercial product showed clear evidence that the microalgal biomass-based hydroponic nutrients have commercialisation potentials Further product improvement by using different microalgal species can yield high and robust nutrients and stimulants.
Please use this identifier to cite or link to this item: