Reduction Of TDS Research Articles

Pre-treatment of petroleum refinery wastewater by coagulation and flocculation using mixed coagulant: Optimization of process parameters using response surface methodology (RSM)

The present work reports the efficacy of three coagulants CuSO4, FeCl3 and CuSO4+FeCl3 (both salt mixed in 1:1 ratio (v/v)) for treatment of wastewater from effluent treatment plant of petroleum refinery using coagulation and flocculation process. The independent parameters such as pH and dosage of coagulants were optimized using response surface methodology with central composite design technique considering final pH, reduction in COD, turbidity, TDS and color as dependent variables. The statistical fitness of developed model was checked using ANOVA. A second order quadratic model (R2> 95 %) was best fitted to develop the relation between independent and dependent variables. Charge neutralization, sweep flocculation, adsorption and formation of tribasic copper chloride (TBCC) were mainly responsible for coagulation and flocculation processes. Results showed that mixed coagulant CuSO4+FeCl3 delivered better result than CuSO4 and FeCl3 individually. CuSO4+FeCl3 along with adsorption and sweep flocculation, forms tribasic copper chloride (TBCC) as a proceeding intermediate in the pH range 5−7. The TBCC formation enhanced the flocculation by destabilizing colloidal and suspended particles due to its catalytic, decolorizing and octahedral structural properties. Maximum reduction in COD (76.77 %), turbidity (89.47 %), TDS (94.16 %) and color (95.29 %) was observed at pH 7.12 and 0.20 g/L dosage of CuSO4+FeCl3 coagulant. The final pH of solution at optimum condition for all three coagulants was under the disposal limits. Further, the flocs formed are characterized using XPS, SEM and EDX analyses to reveal the formation of TBCC as intermediate during the process.

Characterization of textile dyeing effluent and its treatment using polyaluminum chloride

The study aimed to expose the level of pollution owing to textile dyeing effluents and assess the coagulant efficiency of polyaluminum chloride (PAC) for treating the textile dyeing effluents. The discharged of untreated textile dyeing effluents have severely polluted water and soils, threatened the entire environment. The study analyzed the discharged and treated effluents using standard methods of analysis. The optimized parameters of the coagulant PAC were the dose, contact time, temperature, and agitation speed. The color removal efficiency study observed that the coagulant PAC removed the color from 85 to 95% of three dyeing effluents at optimum conditions. The result showed that the maximum reduction of EC, TDS, TSS, COD, BOD, Cl−, HCO3− and SO42− were found to be 83.66, 85.7, 82.05, 82.05, 83.45, 66.91, 66.91 and 72.88%, respectively. It also showed that the coagulant efficiently reduced heavy metals and the highest percentage of reduction achieved was 72.7 and 98.52 for Fe and Pb, respectively, from the effluents. Hence, the PAC would be a potential coagulant for treating the textile dyeing effluents that help to build a sustainable environment.

Up-scaling microbial fuel cell systems for the treatment of real textile dye wastewater and bioelectricity recovery

ABSTRACT In this work the energy recovery in microbial fuel cell was studied by electrically stacking its three individual units into series and parallel arrangements. The power output was higher in parallel stacking by 2.07 and 14.77 times than series and individual units respectively. The rate of degradation of dye wastewater was in order of individual Microbial Fuel Cell (MFC) < series stack < parallel stack. The corn cob biochar was used as an additive in the MFC to improve the efficiency of the individual MFC unit. The addition of 0.5 g corn cob biochar enhanced the power output to 38.6 mW/m2 from 0.47 mW/m2 in the MFC individual unit without the biochar additive. The simultaneous COD reduction, TDS reduction and decolourisation of dye wastewater achieved are 82.14%, 68% and 74.8% respectively. The current work demonstrates that the dose of biochar and parallel stacking are a framework to achieve enhanced dye removal and bioenergy recovery via microbial fuel cell.

Biological Treatability of Low Total Dissolved Solids (LTDS) Using SBR as a Pre-Treatment for Reverse Osmosis

Huge quantity of effluents is generated from pharmaceutical industries attributed to their wide array of manufacturing and maintenance processes. Wastewaters from pharmaceuticals are characterized by the presence of solids, pH, temperature, biodegradable organic compounds, unusual turbidity, hardness and conductivity. Wastewater from pharmaceutical industry arising from various units is categorised as low total dissolved solids (LTDS) and high total dissolved solids (HTDS) based on the concentration of total dissolved solids. The present study focuses on treatment of LTDS using a combination of biological treatment followed by membrane process, reverse osmosis. This research presents the results from the pilot-scale studies focussed on biological treatment using SBR as pre-treatment for RO towards the removal of LTDS effluent. Three-month data on a daily basis is presented. The efficiency of the process was tested with a reduction in parameters like total dissolved solids and chemical oxygen demand. SBR tested for its suitability as a preliminary treatment for the Reverse Osmosis process during the months of August-October. The highest and lowest TDS reduction was recorded as 9.72% and ?4.67% in the month of August. The highest and least COD reduction was recorded as 87.28% and 80.66% in the same month. The highest and lowest TDS reduction was recorded as 0.84% and ?7.92% in the month of September. The highest and least COD reduction was recorded as 87.07% and 83.28% in the same month. The performance of RO tested for its efficiency in removing the TDS and COD after SBR as pre-treatment. The highest and lowest TDS reduction was recorded as 94.93% and 93.27% in the month of August. The highest and least COD reduction was recorded as 96.84% and 90.19% in the same month. The highest and lowest TDS reduction was recorded at 96.53% and 91.25% in the month of October. The highest and least COD reduction was recorded as 94.31% and 72.57% in the same month. SBR has proved to be a promising solution for pre-treatment removing all substances that might result in membrane fouling. Hence, the present study concludes that a combination of SBR and RO will be a promising solution for effective removal of TDS and COD from pharmaceutical wastewaters.

Process validation of integrated bioelectrochemical and membrane reactor for synchronous bioenergy extraction and sustainable wastewater treatment at a semi-pilot scale

Continuous mode semi-pilot scale bioelectrochemical and membrane-integrated system was developed for simultaneous bio-electricity generation and synthetic wastewater treatment. The bioelectrochemical component consisted of a holistic blending of Up-flow anaerobic sludge blanket (UASB) and microbial fuel cell (MFC), whereas hollow fiber ultrafiltration (UF) membrane was incorporated in a series. A maximum power density of 10.3 Wm−3 and current density of 23.9 Am−3 was engendered during the course of bio-electrochemical operation. 91.3% COD and 54.43% TDS reduction was achieved during the integrated operation. Hydraulic retention time (HRT) and substrate concentrations were the prominent factors in the bio-electrochemical segment and coagulation/flocculation used prior to hollow fiber filtration. The voltage output was linearly associated with COD reduction and this could be strategized to develop a bioelectrochemical based biosensor to measure real-time COD in the wastewater treatment plant. A Kinetic study was carried out for an entire integrated system, wherein, theoretical and experimental current generation was linearly correlated. Theoretical net energy produced at a prior stage (0.096626 kW h/m−3) surpasses the overall energy consumed in an integrated system and the inconsistent methane production could further be enhanced with modified reactor conditions. Nevertheless, this cost-effective effluent treatment approach could be a supportive guide to develop a self-sustainable wastewater treatment strategy.

Stabilization of zero valent iron (Fe0) on plasma/dendrimer functionalized polyester fabrics for Fenton-like removal of hazardous water pollutants

This study reports the synthesis, immobilization and stabilization of multiscale zero valent iron (Fe0 = ZVI) particles on fibrous polyester (PET) nonwoven membrane for heterogeneous Fenton-like removal of hazardous pollutants in water. Activation of PET fiber surface by air atmospheric plasma with or without a consecutive grafting of hyperbranched poly-(ethylene glycol)-pseudo generation 5 dendrimer having hydroxyl (-OH) end group functionality created polar reactive functional groups allowing immobilization and stabilization of ZVI particles. Synthesis of ZVI was carried out through chemical reduction of ferric ions, either through a single step in-situ, or a two-step ex-situ reduction-immobilization method. The nonwovens were characterized using wettability, Fourier transform infrared spectroscopy (FTIR), optical microscopy, scanning electron microscopy (SEM), X-ray energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD) and thermo-gravimetric analysis (TGA). Results confirmed the formation and immobilization of nano to sub-micronic multi-scale ZVI particles. The particle size, distribution and stability of ZVI were found to be influenced by the methods of ZVI synthesis and PET surface activation used. The ZVI particles initially formed, quasi-instantaneously turned to yellowish brown indicating the formation of oxide layer, except in the case of dendrimer grafted PET, where higher content (22.30%) and stability of ZVI was detected. All ZVI immobilized nonwovens exhibited high effectiveness towards Fenton-like degradation of malachite green dye (20 ppm), with fastest color removal (98% in 20 min) achieved by dendrimer/ex-situ nonwoven. This nonwoven could be used up to eight repeated cycles providing low TDS (52 ppm) and high COD reduction (66.23%). Combined use of eco-friendly plasma and dendrimer grafting, provides efficient fibrous textile base heterogeneous catalysis.

Amelioration of Physico-Chemical Parameters and Phytotoxicity of Landfill Leachate by Microbial Degradation

Objective: To understand the effect of microbial treatment on physico-chemical parameters and phytotoxicity of leachate arising from degradation of municipal solid waste. Methods and statistical Analysis: Landfill leachate samples were collected from a municipal landfill site in Mumbai, India at different phases of its degradation cycle. The leachate was subjected to anaerobic treatment using microbial consortium based product CleanMaxx ANB followed by its counterpart CleanMaxx for aerobic treatment. Post treatment, the physico-chemical properties were analysed and the phytotoxicity was assessed using seed germination assay. The results were interpreted using ANOVA. Findings: The physicochemical parameters of the old and fresh leachate samples were analyzed after biological treatment where the percentage COD reduction was 18.97% and 53.87%; percentage ammoniacal nitrogen reduction was 22.78% and 58.8 %; percentage reduction in TDS was 24.8% and 34.76%; percentage reduction in TSS was 24.05% and 23.5% and percentage colour reduction was 25.01% and 34.35% for old and fresh leachate respectively. The aging of landfill leachate sample may have reduced its biodegradable fraction with the increase in the concentration of high molecular compounds and highly toxic compounds, which may hinder with the microbial degradation process. The seed germination bioassay using Cicer arietinum (Bengal gram) seeds revealed that the percentage germination of seeds exposed to untreated leachate samples (both old and fresh) was 11.1 and 22.2% respectively (p<0.05). Microbial treatment of both these samples improved the germination percentage to 88.8% in both cases. Application/Improvements: The improvement in physicochemical properties and reduction in phytotoxicity indicates that the microbial remediation of landfill leachate could treat the top soils and groundwater tables at contaminated sites, making the surrounding land arable.Keywords: Landfill, Leachate, Microbial Degradation, Phytotoxicity

Treatment of Waste Water Using Natural Coagulants

The use of natural coagulants like Moringa Oleifera and Okra plants are receiving attention for their effectiveness in waste water treatment. The technologies involved are economical, traditional and easy to implement and ideal for rural areas. The process being biological in nature does not generate any non-treatable wastes. These processes are easy to operate and require little or no maintenance. After the treatment of both the municipal and dairy waste water samples by two natural coagulants Moringa Oleifera and Okra seeds and synthetic coagulant alum, the results show that there is a reduction in the percentage of various polluting parameters like COD, BOD, turbidity, hardness, TSS and TDS etc. In the study different quantity of coagulants doses (50 mg, 200 mg, and 500 mg) were used but it is found that increasing the amount of coagulant increases the removal but it is not proportional and significant with respect to the quantity of coagulant added. By the effect of Moringa Oleifera coagulant the reduction of turbidity, COD, BOD, hardness, TSS and TDS are found to be 61.20 %, 65.3 %, 55 %, 25 %, 69 %, and 68% respectively. There is not much effect on the pH. By the effect of Okra coagulant, the reduction in percentages of turbidity, COD, BOD, hardness, TSS, and TDS are found to be 65 %, 67 %, 56 %, 30 %,72 %, and 69 % respectively. There is no significant change in pH due to natural coagulants. By the effect of alum coagulant the reduction percentages of turbidity, COD, BOD, hardness, TSs, and TDS are found to be 59 %, 59 %, 50.98%, 67 %, and 65 % respectively. The addition of alum makes the water more acidic.

Greywater Treatment Using Single and Combined Adsorbents for Landscape Irrigation

Greywater reuse can be considered as an additional supply of water not only to protect water resources but also to reduce water shortage. Thus, the aim of this research is to examine the feasibility of three adsorbents (activated carbon (AC), Iranian natural zeolite (Z) and stabilized nano zero-valent iron (nZVI)) in single and combined forms to treat greywater for reuse in landscape irrigation. For this purpose, greywater samples were collected from student hostel of Fasa University and analyzed in a batch mode experiment. Also, the adsorption of COD was studied in terms of kinetic, isotherm and thermodynamic models. The results indicated that among the seven treatments, the combination of AC, Z and nZVI had the best performance in greywater treatment. 85.75% removal of COD, 91.81% of TDS and 98.1% of turbidity were achieved by triple combined treatment. In double combined adsorbents, the highest adsorption rate of COD, TDS and turbidity was accomplished when AC+nZVI, AC+Z and nZVI+Z were used, respectively. The results also indicate that single adsorbents alone are not adequate to guarantee a sufficient reduction of COD, TDS and turbidity. Kinetics of COD removal by all treatments obeyed to pseudo-second-order model and the Freundlich isotherm closely fitted the experimental data. The COD data demonstrated that the sorption process is spontaneous and endothermic. The results indicated that the triple combined adsorbents were able to reduce the COD, TDS, turbidity and pH level to the required reuse in landscape irrigation and the results were satisfactory according to Iranian standards.

Electrochemical sulfur production from treating petroleum produced water

An electrochemical cell was used to remove sulfides from synthetic petroleum produced water (PPW). The cell was run for over 2 months in continuous mode. Sulfides were converted to sulfur at anode with an average conversion rate of 65%. Due to the use of a cation exchange membrane to separate cathodic and anodic chambers, along with sulfide removal conductivity and TDS reduction also took place. Conductivity and TDS reduced by 49.27% and 44.79% respectively on anode and was followed by caustic generation at cathode. Thus, in this communication treatment of PPW along with sulfur and caustic generation is being proposed.

Improvement of water quality of remnant from chemical retting of coconut fibre through electrocoagulation and activated carbon treatment

Remnant obtained from chemical retting of coconut fibre was found to have an exorbitant COD, BOD, TDS, sulphide content having blackish brown colour. Traditional (physico-chemical) treatment could not reduce its COD, TDS, colour substantially. Further, the traditional method was lengthy, consumed huge chemicals and time. Present paper reports a quicker, simpler, economic i.e., an industrially viable method to separate the chemicals and biomass by employing electrocoagulation (EC). The performance of EC was analyzed by keeping temperature, and pH of remnant constant, while varying current flow (100–2000 mA), time (15–90 min) and number of iron electrodes (2,4,6). Efficacy of EC was evaluated in terms of reduction in conductivity, pH, TDS, COD, TOC, colour and quantity of sludge generated from the wastewater. Six electrodes with 2000 mA current flow for 90 min were found to give noticeable reduction on COD (92.8%), TOC (56%), TDS (99%), and colour. To reduce pH, and TDS to an acceptable level, filtration with activated charcoal was attempted on recovered water from EC. Resultant water was also found to have acceptable LC50 value for safe disposal. Carbon content (53%) in the sludge was high, contained lignin and cellulose whiskers also, as revealed from the EDX and FTIR, SEM respectively. Cost of EC ($ 0.087 USD/L) was found to be much less as compared to traditional method ($ 0.384 USD/L).

Treatment of hospital waste water by ozone technology

Conventional treatment hospital wastewater need high cost, large area, long time and the final result leaves a new waste known as sludge. Alternative to more efficient and new technologies for treated hospital wastewaters was ozonation. Ozonation is able to oxidized pollutant materials in wastewater. This research is to know the decrease of COD and TDS levels with ozone. Waste water samples used by dr. Adhyatma, MPH Hospitals Semarang. Kruskal-Wallis test for COD and TDS with variation of concentration p-value = 0,029 and 0,001 (p≤0,05) or there is significantly difference between COD and TDS with level of concentration but there were no different between levels of COD, and TDS with reactions time variations p-value = 0,735, and 0,870 (p≥0.05). Ozone efficiently reduction of COD and TDS at a concentration of 100 mg/liter, the lowest mean value at COD 17.47 mg/liter and TDS 409.75 mg/liter.

Biological treatment of toxic refinery spent sulfidic caustic at low dilution by sulfur-oxidizing fungi

One of the major concerns in petrochemical industries is eliminating hydrogen sulfide. Sodium hydroxide solutions are generally used for removing hydrogen sulfide and result in spent caustics which have a pH greater than 11 as well as high sulfide concentrations (2–3% w/v). In this study, SMHS-3 isolate was introduced with the ability to oxidize sulfur media containing sodium sulfide, thiosulfate and elemental sulfur. An analysis based on internal transcribed spacer (ITS) gene indicated that Sadat Mahale hot spring soil (SMHS-3) was closely related to Aspergillus genus. The oxidation results showed that Aspergillus sp. SMHS-3 has the highest sulfur oxidizing ability which produced sulfate in an average range of 0.85 g L−1 after 10 days. Response surface methodology (RSM) was applied to optimize the sulfur decomposition and resulted in a 1.2 fold increase in sulfur conversion rate. Aspergillus sp. SMHS-3 was used in a low-diluted spent caustic bio-treatment, resulting in a 16% reduction of COD, 10% reduction of TDS and 55% removal of active sulfite after 10 days of treatment. Results from this study suggests Aspergillus sp. SMHS-3 as a potential fungal strain for oxidizing sulfur compounds and a possible candidate for spent caustic biodesulfurization.

REMOVAL OF ORGANIC MATERIALS FROM TANNERY WASTEWATER CONTAINING AMMONIA FOR REUSE USING ELECTRO-OXIDATION

Leather manufacturing process generates significant volume of wastewater. Deliming is one of the unit processes, in which about 4.5 L of wastewater is generated per one Kg of pelt. Reuse of wastewater from the unit processes, where significant volume of wastewater is generated is much important to address pollution mineralization and water conservation. Presence of significant level of organic pollutants is the primary factor that deters reuse of waste streams. In this paper, the Electro-Oxidation (EO) of deliming waste streams was carried out. It was found that EO was found to be effective in removing organic pollutants. The effect of process parameters such as pH, current density and duration on removal of organic pollutants was studied. Treatment efficiency was evaluated in terms of Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Kjehldahl Nitrogen (TKN). Results indicate that the pollution reduction was better during electro-oxidation at current density 0.015 A/cm2 and pH 8.0 for 90 min. The kinetics of pollutants removed by electro-oxidation was found to obey pseudo-first order with an R2 value of 0.9963. The reduction in BOD, COD, TKN, chloride and TDS was 87.37%; 81.95%; 82.67%; 5.75% and 6.56% respectively. The possibility of reuse of treated wastewater was also assessed. Treated deliming wastewater was reused for soaking did not show any impairment in quality of pelt and leather. It is concluded that EO was very effective in treating the deliming waste streams rendering the same suitable for reusing for soaking.

Non Chemical Water Treatment Process for TDS Reduction In Cooling Tower - Specific Study on Electrical Conductivity and Turbidity

Non Chemical Water Treatment Process for TDS Reduction In Cooling Tower - Specific Study on Electrical Conductivity and Turbidity

Configuration Analysis of Stacked Microbial Fuel Cell in Power Enhancement and Its Application in Wastewater Treatment

The present study examined the performance of stacked microbial fuel cell for higher power generation and also for treating brewery waste effluent. The stackable microbial fuel cells are connected in series, parallel and series–parallel using standard glucose media produces increased power density of 813, 1546.57 and 2418 $$\hbox {mW\,m}^{-2}$$ , respectively, corresponding to 288 $$\hbox {mW\,m}^{-2}$$ from single cell as control. Series–parallel setup arrangement with brewery effluent produces maximum power density of 1345 $$\hbox {mW\,m}^{-2}$$ with 81% of COD removal efficiency within 72 h of operation. The series–parallel configuration system shows significant COD removal and maximum power density due to their better stability of redox potential in overall cells. The significant reduction of TDS, TSS was also observed in series–parallel connection over other stacking MFCs. The results of the present study highlight the importance of combining electrical circuit along with stacking in generating stable and high power from MFC for practical applications.

Technology Evaluations for COD and TDS Reduction in Leachate

Technology Evaluations for COD and TDS Reduction in Leachate

Evaluation and Comparison of TDS Reduction Processes for Fast-Tracked and Long-Term Upgrades of WWTP in Southern California

Evaluation and Comparison of TDS Reduction Processes for Fast-Tracked and Long-Term Upgrades of WWTP in Southern California

PURIFICATION OF DISTILLERY SPENT WASH BY USING ACTIVATED CHARCOAL

Purification of distillery spent wash using activated charcoal has great potential as a sustainable method as it is cost effective method. The purpose of this investigation is to study the activated charcoal purification method for purification of distillery spent wash. For this, the study encompassing evaluation of reduction of various physical chemical parameters (pH, COD, TS, TDS, Ca, Mg, Na and K) of distillery spent wash was done by passing it through the activated charcoal column. The distillery spent wash was acidic (pH 4.7) and dark brown in color which often cause psychological fear in farmers for its utilization. Activated charcoal purification of distillery spent wash exhibited maximum reduction in COD (48.98%), TS (64%), TDS (55.26%), Mg (78.03%), Na (60%), Ca (80.91%), K (75.30%) and increase in pH toward pH 7. Purified distillery spent wash showed a good growth of wheat seeds.

Investigation of Coagulation Activity of Cactus Powder in Water Treatment

This paper is focused on the comparative study of cactus powder, Alum, and their combination of physiochemical analyses of water sample such as TDS, pH, conductivity, salinity, and turbidity using jar test. The result indicated that percentage removal of turbidity from turbid water sample increased from 23.9% to 54% and 28.46% to 58.2% as dose increased from 0.50 to 3.50 g for both cactus powder and Alum, respectively. Cactus powder also has a marginal effect on pH value (7.33 at 0.50 g, 7.49 at 1.50 g, 7.57 at 2.50 g, and 7.57 at 3.50 g) as compared to the usage of chemical coagulants (Alum). The salinity was increased from 0.4% to 0.69 % and 0.39% to 0.98% as the dose of cactus powder and Alum increased from 0.50 g to 3.50 g, respectively. The result revealed that cactus powder is more effective in pH upholding, TDS maintenance, and salinity removal than Alum, but their combination is the most effective in terms of turbidity removal, reduction of salinity, reduction of conductivity, and reduction of TDS and has a marginal effect on dissolved oxygen (DO) value. In conclusion, the combination of Alum and cactus powder is more effective for turbidity removal, salinity removal, and pH and conductivity upholding than either of them used individually.