Table 10.
Modern methods of treatment of wastewater effluent from different sources
| S.No | Type of industry | Effluent composition | Recent advancements in effluent treatment | Treatment category | Target of removal | Merits | Demerits | References |
|---|---|---|---|---|---|---|---|---|
| 1 | Electric power plants | Methane, siloxanes, carbon-dioxide, ammonia, hydrogen sulphide, suspended solids | Development of microbial fuel cell with biocatalysts for concurrent electricity production and pollutant removal from effluent | Biological | Ammonia, Carbon-dioxide, methane through nitrification, denitrification and bio-mineralization | Offers better aversion to environmental stress | High cost and short life span | Guo Y et al. (2020) |
| 2 | Battery manufacture | Metals like aluminium, cobalt, copper, lead, iron, hydrogen fluoride, lithium, manganese and nickel | Application of pyro, hydro and biohydro—metallurgy for metal extraction from the effluent | Mechano-chemical | Nickel, lithium, cobalt | Separation of valuable metals and economically viable | Reliant to chemical composition and high energy consumption | Mossali E et al. (2020) |
| 3 | Nuclear power plants | Gaseous (inert gas, halogen, aerosol) and liquid (tritium) radioactive substances | Solidification with barriers to cease water and prevent the water radio-nuclide migration and droning in intense development secluded with biosphere | Chemical | Radioactive materials | Harmless to ecosystem and human beings | High operational cost | Ye et al. (2016) |
| 4 | Mines and quarries | Sulphide minerals such as suchlike pyrite (FeS2), pyrrhotite (FeS) | Bioremediation and phytoremediation that relies on microbes to degrade the organic contaminants in the wastewater effluent | Biological | Polymetallic sulphides | Economical and less disruptive to the environment | Sensitive to toxicity level | Agboola O et al. (2020) |
| 5 | Food | Organic compounds, suspended solids, sugar, fats, color, preservatives and nutrients | Employment of hydrophobic neoteric solvents as extractants such as eutectic solvents, ionic liquids, bio-based solvents etc. for phenolic compound separation from food effluents via liquid–liquid extraction | Physico-chemical | Phenolic compounds (flavonoids and non-flavonoids) | Facilitates the separation of high value-added compounds such as phenolic anti-oxidants | Time consuming process and the solvent should be evaporated to concentrate the extract | Canadas R et al. (2020) |
| 6 | Agriculture | Antibiotics, synthetic compounds, organic compounds and suspended solids, nitrogen and phosphorus | Incorporation of micro-algae into wastewater effluent based on autotrophic nitrification and heterotrophic denitrification for intensified biological N & P removal | Biological | Nitrogen, phosphorus and other organic waste | Eco-friendly and sustainable alternative to conventional biological treatment | High energy requirement and overall cost | Mohsenpo ur SF et al. (2020) |
| 7 | Dairy | Lactose, fats, whey proteins, chlorides, sulphate, soluble organics, suspended and dissolved solids, BOD, COD | Implementation of unmodified rice husk (by-product of rice milling) as a biosorbent which gets protonated at low pH and thereby capturing the organic materials to the binding sites | Physico-chemical (adsorption) | Organic substances | Easy accessibility of raw materials and cost-effective | Usage of high adsorbent dosage leads to COD loading | Pathak U et al. (2016) |
| 8 | Oil extracting mills | Organic carbon, nitrogen, methane, carbon-dioxide, hydrogen sulphide, suspended solids, BOD, COD | Utilization of palm kernel shell for the development of biomass adsorbent through the integration of zeolite and iron oxide for the adsorption of organic pollutants from the effluent | Physico-chemical (adsorption) | Heavy metals, diligent organic/inorganic contaminants | Increased stability and adsorption efficiency, good separation, aids in the conversion of solid waste to useful adsorbent | High pre-production cost | Jun KC et al. (2020) |
| 9 | Petroleum and petrochemicals | Dissolved oil, hydrocarbons, gases like H2S, CO2 and organic acids | Hybrid system using continuous flow intermittent cleaning biofilm technology -based moving bed biofilm reactor and assimilated native microbial association – based continuous stirred tank bioreactor | Biological | COD and total petroleum hydrocarbons | High resistance to toxic effects, increased mass transfer between hydrocarbon and biocatalyst, highly precise | High operational and maintenance costs | Kuyukina MS et al. (2020) |
| 10 | Organic chemicals | Crude oil and grease, hydrocarbons, BOD, resins, pesticides, synthetic fibers, organic chemicals (benzene, toluene, phenols, etc.) and heavy metals (chromium, lead, copper etc.) | Integrated treatment involving fixed biofilm bioreactor, two-phase partitioning bioreactor, sequencing batch reactor to remove the toxic pollutants | Physico-chemical, biological | Heavy metals and other inorganic matter | Technologically and economically feasible | Sedimentation is required to prevent clogging, time-consuming | Awaleh MO et al.(2014) |
| 11 | Leather | Volatile organic compounds, heavy metals, COD, BOD, dissolved solids, sulphides, calcium/ammonium salts, chromium, H2S | Employment of waste tea leaves (dropped out from teashops/residence) for heavy metal removal from the tannery effluent, due to its good biosorption ability | Physico-chemical (adsorption) | Heavy metals like chromium, iron, nickel, lead | Effective, inexpensive, copiously obtainable cheap | Release of soluble carbon content and applicable only for heavy metal removal | Nur-E-Alam et al. (2020) |
| 12 | Paper and pulp | Suspended solids, organic matter, chlorinated resin acids, wood extractives, lignin, cellulose, tannins, diterpene alcohols, BOD, COD | Incorporation of fungal consortium (Nigrospora sp., curvularialunata sp.) to remove BOD, COD, lignin and bacterial consortium (actinomycetes sp.) that generates laccase enzyme to degenerate cellulose and lignin under alkaline environment | Biological | Lignin, cellulose/hemi-cellulose, BOD, COD | Cost effective, ecofriendly | Complexity in micro-biological mechanism, slow process | Ram C et al. (2020) |
| 13 | Iron and steel | Oil and grease, phenol, cyanides, ore particles, sulfur compounds and metal ions | Employment of steel slags (containing iron oxide) to remove metallic iron, and steel slag-based induction furnace for chromium removal | Physico-chemical method (adsorption) | Heavy metals | Economically sustainable, reuse of steel waste | Stability problems | Branca TA et al. (2020) |
| 14 | Pharmaceutics | Dissolved and suspended solids, COD, organic matter such as alcohol, aromatic compounds, acetone, antibiotics, chlorinated hydrocarbons | Molecularly imprinting technology that employs molecularly imprinted polymers to produce affinity membranes for the removal of antibiotics from water | Physico-chemical method (membrane filtration) | Antibiotic-tetracycline | High selectivity, affinity, stability, easier operation | High utilization of template molecules | Gadipelly C et al. (2014) |
| Nanofiltration which is pressure driven membrane separation process for eliminating the antibiotic concentration from the wastewater effluent | Physico-chemical method (membrane filtration) | Antibiotic-amoxicillin | High operational efficiency | Expensive and high energy consumption | ||||
| 15 | Textile | Dyes and fibers (reactive, vat, azoic), toxic chemicals (acids, alkali, surfactant-dispersing agents), heavy metals (copper, chromium, cadmium, zinc etc.) | Photocatalytic degradation using TiO2 nanoparticles, | Chemical (photocatalysis) | Dyes | Application of nanotechnology in textile effluent treatment is efficient in eliminating and retrieving pollutants | Costly, instability of nanoparticles | Kumar PS et al. (2017) |
| Carbon-based nanomaterials | Physico-chemical (adsorption of pollutants) | Organic/inorganic contaminants | ||||||
| Nanosorbents | Physico-chemical (adsorption of pollutants) | Metal oxides | ||||||
| Zeolites, carbon nanotubes, | Physico-chemical (adsorption of pollutants) | Heavy metals |