Treatment of Rose Oil Processing Effluent with Chlorella sp. Using Photobioreactor and Raceway

Assessing the potential of Chlorella sp. phycoremediation liquid digestates from brewery wastes mixture integrated with bioproduct production

Digestates from different anaerobic digesters are promising substrates for microalgal culture, leading to effective wastewater treatment and the production of microalgal biomass. However, further detailed research is needed before they can be used on a large scale. The aims of this study were to investigate the culture of Chlorella sp. in Digestate_M from anaerobic fermentation of brewer's grains and brewery wastewater (BWW) and to explore the potential use of the biomass produced under different experimental conditions, including diverse cultivation modes and dilution ratios. Cultivation in Digestate_M initiated from 10% (v/v) loading, with 20% BWW, obtained maximum biomass production, reaching 1.36 g L^-1 that was 0.27g L^-1 higher than 1.09 g L^-1 of BG11. In terms of Digestate_M remediation, the maximum removal of ammonia nitrogen (NH₄ ⁺-N), chemical oxygen demand, total nitrogen, and total phosphorus reached 98.20%, 89.98%, 86.98%, and 71.86%, respectively. The maximum lipid, carbohydrate, and protein contents were 41.60%, 32.44%, and 27.72%, respectively. The growth of Chlorella sp. may be inhibited when the Y(II)-F_v/F_m ratio is less than 0.4.

Recycling of wet grinding industry effluent using effective Microorganisms™ (EM)

A considerable volume of effluent released from the food processing industries, after the extensive use in the products manufacturing and industrial process. Effluents, either without treatment or with improper treatment, released out from the industries would severely damage the environment and human health. An investigation was done by recycling the effluent samples, collected from the wet grinding industry, Madurai, India, which was determined with an acidic pH (5.93), high turbidity (160.78 NTU), high BOD (62.4 mg/l) and COD (274.38 mg/l) and a significantly higher quantity of starch (115.81 mg/l). Biological wastewater treatment method was chosen in this experiment on the basis of the biodegradability index of effluent (3.21-10.75). The main goal of this study was to evaluate the effectiveness of wastewater treatment in a prototype STP utilizing the Effective Micro-organisms™ Consortium application. The US EPA International Water Quality Standards and the Water Quality Index were used to compare the water quality of the recycled effluent with and without the EM application. The effluent from the EM consortium treatment was found to have acceptable levels of pH (7.38), salinity (1.94 ppt) and Conductivity (4.05 mS); and a declining trend found in TDS (1.81 ppt), BOD (24.4 mg/l) and COD (148.83 mg/l) level when the effluent treated using EM. Removal effectiveness of EM significant reduce in the treated effluents starch (85.15%), sulphate (78.42), phosphate (79.60), nitrogen (65.54%), and turbidity (82.73%) level were observed. Which was shown to be comparatively better than employing without EM treatment. This research substantially intends to the best practices, towards sustainable industries through Cleaner Production Mechanism.

Sustainable microalgal biomass production in food industry wastewater for low-cost biorefinery products: a review

Microalgae are recognized as cell factories enriched with biochemicals suitable as feedstock for bio-energy, food, feed, pharmaceuticals, and nutraceuticals applications. The industrial application of microalgae is challenging due to hurdles associated with mass cultivation and biomass recovery. The scale-up production of microalgal biomass in freshwater is not a sustainable solution due to the projected increase of freshwater demands in the coming years. Microalgae cultivation in wastewater is encouraged in recent years for sustainable bioeconomy from biorefinery processes. Wastewater from the food industry is a less-toxic growth medium for microalgal biomass production. Traditional wastewater treatment and management processes are expensive; hence it is highly relevant to use low-cost wastewater treatment processes with revenue generation through different products. Microalgae are accepted as potential biocatalysts for the bioremediation of wastewater. Microalgae based purification of wastewater technology could be a universal alternative solution for the recovery of resources from wastewater for low-cost biomass feedstock for industry. This review highlights the importance of microalgal biomass production in food processing wastewater, their characteristics, and different microalgal cultivation methods, followed by nutrient absorption mechanisms. Towards the end of the review, different microalgae biomass harvesting processes with biorefinery products, and void gaps that tend to hinder the biomass production with future perspectives will be intended. Thus, the review could claim to be valuable for sustainable microalgae biomass production for eco-friendly bioproduct conversions.

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