Micro-algae and wastewater treatment

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The conventional Primary and Secondary Wastewater Treatment processes are being used almost everywhere in order to remove settled materials and to oxidize the organic material present in wastewater. The final outcome is a clear, apparently clean effluent which is usually discharged into natural water bodies. This secondary effluent is, loaded with inorganic substances like Nitrogen and Phosphorus which causes eutrophication and long-term problems. Microalgae culture is an effective method for wastewater treatment as it provides a tertiary biotreatment along with the production of valuable biomass, which can be used for various purposes. Microalgae cultures is a better solution to tertiary and quandary treatments as microalgae can enhance their growth with the use of inorganic Nitrogen and Phosphorus. Also, they can help in the removal of toxic organic compounds and thus does not lead to secondary pollution.

Microalgae have two major advantages over higher plants with respect to biofuels production:

 1.Biomass productivities are measurably greater for microalgae.

2. Cultivation of microalgae does not require Arable land or fresh water as it can be carried out even in shallow ponds using brackish water or saline water. Much research is going on this topic of anaerobic digestion by Microalgae. Only few studies have been published yet.

Some purposes of Algae in Wastewater Treatment are:

 

Reduction of BOD

Removal of Nitrogen and/or Phosphorous

Inhibition of coliforms

Removal of heavy metals.

 

Higher concentration of Nitrogen and Phosphorous in most wastewaters also means that they can be used as cheap nutrient sources for algal biomass production. This algal biomass can be used for:

Composting, CH4 production, Production of liquid fuels ((pseudo-vegetable fuels), as animal feed or in aquaculture and

production of fine chemicals.










References:

https://doi.org/10.1016/j.sjbs.2012.04.005

Water pollution biology, Ellis Horwood Series in Wastewater Technology, Ellis Horwood Ltd., John Wiley & Sons, Chichester (1989)

Google Scholar

 

Toxicological response of the green alga Chlorella vulgaris to some heavy metals

Am. J. Environ. Sci., 6 (3) (2010), pp. 230-237

CrossRef     Google Scholar

 

Algal Biomass echnologies

Beih. Nova Hedwigia (1986), p. 83

Google Scholar

 

 

 

 

Comments

  1. BhaskarNovember 6, 2020 at 7:14 AM

    Cultivation of Micro-algae is still a new topic. Lot of research going on this. Until they come up with a better solution.

    ReplyDelete
  2. UnknownNovember 6, 2020 at 7:27 AM

    This method is interesting compared old conventional methods in Wastewater treatment.  Good work .

    ReplyDelete

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