FILTRATION TREATMENT OF DAIRY PROCESSING WASTEWATER

The influent and effluent wastewaters of a Sequencing Batch Reactor (SBR) wastewater treatment system used by a dairy processing plant were evaluated over a two‐month period. Pollution parameters measured were biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total solids (TS), and pH. Viable biomass of the samples was determined by adenosine triphosphate (ATP), measured in Relative Light Units (RLU) and heterotrophic plate count (HPC). The following average overall reduction of pollution parameters was achieved by the SBR system: BOD, 97%; COD, 93%; TSS, 97%; and TS, 76%. Biochemical oxygen demand was highly correlated with COD, TS, TSS, HPC, and ATP in the effluent. A significant correlation was also observed between ATP and HPC. The pH of the influent and effluent ranged from 7 to 8. The average daily effluent flow rate of the waste disposal system was approximately 94,625 liters with an average BOD of 8mg/l, COD of 72mg/l, TSS of 15mg/l, TS of 728mg/l and pH of 7.62. With the efficient reduction of BOD, COD, TS, and TSS, the SBR system was effectively used for the primary and secondary treatment of wastewater.

Toxic and harmful metals found in wastewaters are released to the environment, and this affects the living (flora and fauna including beneficial microbes) systems. An efficient and low-cost process facilitating their treatment needs to be established. Bioremediation (metallic biodegradations) is an optimistic scheme due to its low expenditure, high proficiency, and eco-friendly nature. The ability of microbes can be used as a lucrative option for eliminating/reducing chromium from the effluent by bioremediation methods. Recently, much works have been done facilitating the understanding of the interaction between the metal and the microbial communities. Such interaction is further utilized for the detoxification of different metals. Effluent is one of the hazardous pollutants of tannery industry. Higher amounts of chrome powder and chrome liquor are used during the process of tanning. Chromium an important pollutant is famous for mutagenicity, carcinogenicity, and teratogenicity in humans, experimental animals, and plants. The removal of Cr (VI) either by reduction or biosorption can significantly reduce the dangers to human body. Bio-adsorption refers to an uptake mechanism of the constituents in the wastewater by employing the living organisms. The findings of the present study demonstrated that the bacterial strain could efficiently reduce the toxic and chromium form aerobically. Strain 1 has shown a maximum capacity (98.77%) to biosorb the chromium from 100 ppm chromium aqueous solution. As the isolated bacterial strain is an excellent reduction potential of chromium, it can be exploited at the commercial level for bioremediation of chromium-contaminated environments. The tannery wastewater was analyzed and physicochemical parameters such as alkalinity, total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), chloride, dissolved solids(DO), biological oxygen demand (BOD), chemical oxygen demand (COD), phosphate, sulfate, silicate, nitrite, nitrate, hardness, calcium, magnesium, iron, and chromium (Cr). The values are when compared with Indian standard. In this work, focus was made on the removal of cations and anions by using low-cost adsorbent, namely coir pith activated carbon. This treatment has resulted in the reduction of COD, Chloride, TS, TDS, TSS, Calcium, and chromium in 1, 10, 50, and 100% diluted tannery effluent. The results indicate that the bacterial strains have exhibited the capacity for the detoxification mechanism of chromium at low at the same time, higher adsorption capacity under a wide range of environmental circumstances. The possibility of the use of these bacterial strains for the reduction of the toxic metal in the industrial wastewater has been assessed. The identified organisms can be further employed for eco-friendly cleanup processes.

A vermifilter system for reducing nutrients and organic-strength of dairy wastewater

Coagulation/flocculation process in the treatment of abattoir wastewater

Recently, the Asian rivers have faced the strong reduction of riverine total suspended solids (TSS) flux due to numerous dam/reservoir impoundment. The Red river system is a typical example of the Southeast Asian rivers that has been strongly impacted by reservoir impoundment in both China and Vietnam, especially in the recent period. It is known that the reduction in total suspended solids may lead to the decrease of some associated elements, including nutrients (N, P, Si) which may affect coastal ecosystems. In this paper, we establish the empirical relationship between total suspended solids and total phosphorus concentrations in water environment of the Red river in its downstream section from Hanoi city to the Ba Lat estuary based on the sampling campaigns conducted in the dry and wet seasons in 2017, 2018 and 2019. The results show a clear relationship with significant coefficient between total suspended solids and total phosphorus in the downstream Red river. It is expressed by a simple equation y = 0.0226x0.3867 where x and y stand for total suspended solids and total phosphorus concentrations (mg/l) respectively with the r2 value of 0.757. This equation enables a reasonable prediction of total phosphorus concentrations of the downstream Red river when the observed data of total suspended solids concentrations are available. Thus, this work opens up the way for further studies on the calculation of the total phosphorus over longer timescales using daily available total suspended solids values.

The rapid growth of industries has resulted in wastewater generation containing different organic and chemical substances channeled into the water body. This causes the arising of water pollution issues in many regions. The phytoremediation method was introduced in the process of treating water pollution as it is low cost and environmentally friendly. Lemna minor, Salvinia minima, Ipomoea aquatica and Centella asiatica were chosen in this study because they have tolerance to various pollution conditions and are able to remove organic pollutants and heavy metals. The objectives of this study were to determine the water quality before and after treatment, to determine the rate of reduction in total suspended solids (TSS), ammoniacal nitrogen (NH3-N), and chemical oxygen demand (COD) in sewage water through the phytoremediation method and to assess the effectiveness of the plants in the phytoremediation of sewage wastewater. It was found that, Lemna minor, Salvinia minima, Ipomoea aquatica and Centella asiatica were able to reduce TSS by 50.8%, 77.6%, 85.6% and 67.6%, respectively; NH3-N by 80.4%, 89.9, 97.3% and 79.1%, respectively; and COD by 75%, 82%, 44.8% and 36.46%, respectively. In this study, it was found that sewage wastewater treatment using Ipomoea aquatica was more efficient in reducing NH3-N and Salvinia minima was more efficient in reducing TSS and COD values.

BACKGROUNDCoagulation/flocculation is a physico‐chemical method for the treatment of olive mill wastewater (OMW). Coagulation/flocculation and precipitation of the agglomerates formed relies on the effective decrease of the electrical charge of the suspended solids which allows particles to approach each other and form large clusters. The present work focuses on the decrease of the electrical charge of the suspended particles by monitoring the changes in the zeta potential of the particles. This approach can also indicate with accuracy the exact concentration of the coagulant or flocculant that must be added in the wastewaters, to achieve the highest removal of the solids and organic load.RESULTSIn the present paper, experiments of coagulation/flocculation with electrolytes [FeCl3, Ca(OH)2, CaO, CaCl2] and polyelectrolytes (PDADMAC, PAH, PAA, PEI, Floccan 22‐23) are presented, either separately or in combination and screened with respect to their removal efficiency in terms of chemical oxygen demand (COD), total suspended solids (TSS), Total solids (TS) and total phenols (TP) removal and by monitoring the zeta potential. A relevant literature review is presented also regarding the coagulants and flocculants which have been examined for the physico‐chemical treatment of OMW. The compounds used, their concentrations and their removal efficiency in terms of COD, TS, TSS and phenols are listed, where possible.CONCLUSIONSThe coupling of calcium hydroxide at 20 g L−1, with PDADMAC in a range of 0.75–2.00 g L−1 led to reductions of COD, TSS, TS and phenols up to 56%, 27%, 43% and 76%, respectively. © 2014 Society of Chemical Industry

This work tests experimentally the capacities of water hyacinth (Eichhornia crassipes) and duckweed (Lemna gibba) to purify wastewater in Marrakesh.1)Eichhornia crassipes was grown in continuous culture with a constant flow rate of 10 l.min.−1 Organic, bacterial and parasitical loads were examined to determine the efficiency of the system. The results show that water hyacinth is well suited to the climatic conditions of Marrakesh. Domestic sewage purification by water hyacinth leads to satisfactory efficiency during the summer with an 87% reduction in chemical oxygen demand (COD) and 95% reduction in total suspended solids (TSS). Bacterial load reduction expressed by control of faecal contamination bacteria achieved 2 log units for a short theoretical retention time (7 days). Moreover, this process reduced parasitic helminth eggs to undetectable levels.2)Lemna gibba was grown in continuous culture with a constant flow rate of 3 1. day−1. Only organic loads were examined. Three categories of influents were tested to determine the system efficiency. The results obtained show that Lemna gibba has the capacity to purify a low organic load (COD:305–530 mg.l−1). The average influent COD was reduced by 82%. During the summer period the average influent COD and TSS has been reduced by 61% and 82% respectively.

Pre-consumer waste from supermarkets, such as vegetables and fruits dreg are always discarded as solid waste and disposed to landfill. Implementing waste recovery method as a form of waste management strategy will reduce the amount of waste disposed. One of the ways to achieve this goal is through fermentation of the pre-consumer supermarket waste to produce a solution known as garbage enzyme. This study has been conducted to produce and characterize biocatalytic garbage enzyme and to evaluate its influence on palm oil mill effluent as a pre-treatment process before further biological process takes place. Garbage enzyme was produced by three-month long fermentation of a mixture of molasses, pre-consumer supermarket residues, and water in the ratio of 1:3:10. Subsequently, the characterization of enzyme was conducted based on pH, total solids (TS), total suspended solids (TSS), total dissolved solids (TDS), chemical oxygen demand (COD), and enzyme activities. The influence of produced enzyme was evaluated on oil & grease (O&G), TSS and COD of palm oil mill effluent (POME). Different levels of dilution of garbage enzyme to POME samples (5%, 10%, 15%) were explored as pre-treatment (duration of six days) and the results showed that the garbage enzyme contained bio-catalytic enzyme such as amylase, protease, and lipase. The pre-treatment showed removal of 90% of O&G in 15% dilution of garbage enzyme. Meanwhile, reduction of TSS and COD in dilution of 10% garbage enzyme were measured at 50% and 25% respectively. The findings of this study are important to analyse the effectiveness of pre-treatment for further improvement of anaerobic treatment process of POME, especially during hydrolysis stage.

Decolorization and decontamination of textile wastewater by gamma irradiation in presence of H2O2

The objective of this study was to establish a suitable chemical process to recover magnesium compounds from Dead Sea water using a selective precipitation process. The recovered magnesium hydroxide (Mg(OH)2) and magnesium chloride (MgCl2) are applicable for wastewater treatment processes since they can effectively remove total suspended solids (TSS) and chemical oxygen demand (COD). Magnesium salts recovered from Dead Sea water were compared with cationic polyacrylamide (PAM) and inorganic salts, including aluminum sulfate Al2(SO4)3, ferric chloride (FeCl3), and ferrous sulfate (Fe2SO4) to investigate the removal efficiency of TSS and COD from wastewater using a chemical precipitation method by using coagulation and flocculation process. Results show that Mg(OH)2 yielded the highest TSS and COD removal efficiencies of 59 and 57%, respectively, with a wastewater pH of 11.5. MgCl2 yielded lower removal efficiencies of 46 and 44%, respectively; at pH 10.5, lower magnesium concentration doses were needed. The most effective chemical precipitation method for removal involved cationic PAM coagulants, resulting in an 86% reduction in TSS and a 65% reduction in COD. Combining commercial Fe2SO4 and MgCL2 recovered from Dead Sea water reduced up to 90 and 73% of TSS and COD, respectively.

Integrated membranes for the recovery and concentration of antioxidant from olive mill wastewater

Chitosan is a natural organic polyelectrolyte of high molecular weight and charge density; obtained from deacetylation of chitin. This study explored the potential and effectiveness of applying chitosan‐magnetite nanocomposite particles as a primary coagulant and flocculent, in comparison with chitosan for pre‐treatment of palm oil mill effluent (POME). A series of batch coagulation processes with chitosan‐magnetite nanocomposite particles and chitosan under different conditions, i.e. dosage and pH were conducted, in order to determine their optimum conditions. The performance was assessed in terms of turbidity, total suspended solids (TSS) and chemical oxygen demand (COD) reductions. Chitosan‐magnetite particles showed better parameter reductions with much lower dosage consumption, compared to chitosan, even at the original pH of POME, i.e. 4.5. At pH 6, the optimum chitosan‐magnetite dosage of 250 mg/L was able to reduce turbidity, TSS and COD levels by 98.8%, 97.6% and 62.5% respectively. At this pH, the coagulation of POME by chitosan‐magnetite was brought by the combination of charge neutralization and polymer bridging mechanism. On the other hand, chitosan seems to require much higher dosage, i.e. 370 mg/L to achieve the best turbidity, TSS and COD reductions, which were 97.7%, 91.7% and 42.70%, respectively. The synergistic effect of cationic character of both the chitosan amino group and the magnetite ion in the pre‐treatment process for POME brings about enhanced performance for effective agglomeration, adsorption and coagulation.

A Laboratory Scale Sequencing Batch Reactor with the Addition of Acetate to remove Nutrient and Organic Matter in Pig Slurry

Tofu industrial wastewater has a Chemical Oxygen Demand (COD) and Total Suspended Solid (TSS) value exceeding the environmental quality standards. The high value of COD and TSS of tofu industrial wastewater is caused by the high content of organic matter and if there is no treatment, the liquid waste of the tofu industry can cause pollution in the aquatic environment. One of the biological processing of tofu industrial wastewater is the bioremediation process using microorganisms. This study aims to determine the ability of the effective microorganisme-4 (EM-4) on reduction of COD and TSS in tofu industrial wastewater. This research was conducted by mixing tofu industrial wastewater and effective microorganism-4 solution into the reactor with various concentrations of EM-4 3%, 5%, 7% and 10% and residence time for 2 days, 4 days and 6 days. The parameters were measured of COD, TSS and pH. The results showed that the tofu industrial wastewater treatment using EM-4 solution with a concentration of 10% for 6 days gave the best results, namely a decrease in COD by 70%, an increase in pH to 8.36 and TSS by 180 mg/L