Removal of tungsten oxyanions from industrial wastewater by precipitation, coagulation and flocculation processes

Untreated wastewater from textile industries when discharged to nearby waterways would cause considerable health concerns to humans and animal life and to the host environment. They contain various chemicals such as dyes, detergents and surfactants, some of which are recalcitrant to biodegradation. Such wastewater can be better remediated by chemical treatment. The treatment of a textile bleaching and dyeing industrial wastewater was done by Coagulation and Flocculation Method using a jar test apparatus. Alum, polyaluminum chloride (PAC), and ferrous sulfate were used in separate runs as coagulants, while excelfloc 264 (a polyacrylamide copolymer) was used as flocculant. Preliminary tests were first conducted to determine the appropriate coagulation and flocculation agitation rates and settling time. The initial pH of the sample effluent was varied from 5 to 8 for alum coagulation, 5 to 8.5 for PAC coagulation and 9 to 11 for ferrous sulfate coagulation. The dosages of each coagulant and the excelfloc were varied from 200 to 1000 ppm, and 0.5 to 2.5 ppm, respectively. Experimental results showed that the optimum initial pH of the wastewater using alum, PAC, and ferrous sulfate were 7, 7.5, and 10, respectively. The optimum dosages of the coagulants were found to be 600ppm for alum and 800ppm for both PAC, and ferrous sulfate. The optimum flocculant dosages were 1.5ppm with alum, 1 ppm with PAC and 2ppm with ferrous sulfate. The highest percentage removal of COD, Total Suspended Solids (TSS), Total Dissolved Solids (TDS), chromium, and color were found to be 58.55%, 65%, 36.51%, 76.45%, and 78.96%, respectively, using alum: 65.4%, 67.5%, 35.84%, 44.92%, and 75.49%, respectively using PAC; and, 55.72%, 34.16%, 33.95%, 19.88%, and 48.56%, respectively, using ferrous sulfate. Among the three coagulants tried, coagulation with PAC gave the highest percentage of COD removal of 65.64% and TSS removal of 67.5% while alum gave the highest removal of both chromium and color at 76.45% and 94.49%, respectively. Rapid and slow agitation rates used were 240rpm for 1 minute and 40rpm for 20 minutes, respectively; while settling time was 30 minutes. Kinetics of the COD removal was studied at the optimum conditions. Kinetic model, determined by curve fitting with the coagulation/flocculation reaction, was observed to follow a first-order rate of reaction.

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Performance Evaluation of Phosphorous Removal by Coagulation using Natural Coagulants

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.b1025.1292s219 ◽

2019 ◽

Vol 9 (2S2) ◽

pp. 106-109

Keyword(s):

Industrial Wastewater ◽

Natural Waters ◽

Mixing Time ◽

Settling Time ◽

Calotropis Procera ◽

Phosphorous Removal ◽

Coagulation And Flocculation ◽

Natural Coagulants ◽

Hyacinth Bean ◽

Banana Leaves

Phosphorous is one of the major nutrients contributing the increased eutrophication of lakes and natural waters. The concentration of phosphorus in domestic sewage is generally adequate to support aerobic biological wastewater treatment. Coagulation and flocculation processes can also to remove phosphorous from industrial wastewater.In this experimental study, an attempt is made to feasibility of natural coagulants like Cassia Alata, Calotropis Procera, Hyacinth bean, Banana leaves, Carcia Papaya, Acacia mearnsii, Jatropha Curcas, Cactus and Tamarind seeds on the decrease of Phosphorous from Industrial wastewater. The batch coagulation test was done to optimum graph was plotted between the removal efficiency all the chose coagulated. From the optimum trails, that the rate of phosphorous removal is more for hyacinth bean with a level of 75, trailed by casuarinas leaves with 74% and Banana leaves with 73%. Tamarind seed demonstrates the least Phosphorous expulsion from the wastewater with 56%. From the optimum trails, the Hyacinth bean can be utilized as a successful coagulant for the expulsion of phosphorus from the wastewater. In the optimum trails coagulation studies were carried out to investigate the factor like optimum dosage, pH, initial concentration of Phosphorous, Mixing time and the settling time which influences the removal of phosphorous by coagulation process. From the study, it might be inferred that the maximum percentage removal of phosphorous was acquired for the coagulant measurement of, pH of 8, the initial phosphorous concentration of, mixing time of and settling time of 45 minutes. It might be presumed that the Phosphorous removal from the industrial wastewater of 95% was conceivable when we kept up the optimum condition by the coagulation procedure..

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Development of Treatment Technology for Dye Containing Industrial Wastewater

Journal of Scientific Research ◽

10.3329/jsr.v2i3.4302 ◽

2010 ◽

Vol 2 (3) ◽

pp. 567 ◽

Cited By ~ 12

Author(s):

M. S. I. Mozumder ◽

M. A. Islam

Keyword(s):

Activated Charcoal ◽

Congo Red ◽

Industrial Wastewater ◽

Dye Removal ◽

Treatment Technology ◽

Promising Alternative ◽

Coagulation And Flocculation ◽

Major Mode ◽

Removal Processes ◽

Removal Studies

The removal of Congo red was carried out by heating with changing pH, using coagulant and by adsorption. Acidic pH was favorable for the removal of Congo red by heating. It is possible to remove a major portion of Congo red just by decreasing the pH (< 4). Removal studies suggest that coagulation might be the major mode of dye removal. It is becoming a promising alternative to replace or supplement the present dye removal processes from wastewater. In these studies, removal of Congo red from aqueous solution by coagulation and flocculation was investigated. Treatment with alum and lime was found to be the most effective. Activated charcoal is also an effective adsorbent for the removal of Congo red. From the isotherm (Langmuir and Freundlich) and kinetics study we find that the Congo red-activated charcoal system has high affinity and capacity. Keywords: Congo red; Coagulation; pH; Temperature; Adsorption; Activated charcoal. © 2010 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.DOI: 10.3329/jsr.v2i3.4302 J. Sci. Res. 2 (3), 569-578 (2010)

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RESEARCH AND EVALUATE TREATMENT EFFICIENCY ON TAPIOCA PROCESSING INDUSTRIAL WASTEWATER BY AEROBIC BIOFILTER TECHNOLOGY WITH VARIOUS MATERIALS

Science and Technology Development Journal ◽

10.32508/stdj.v13i3.2143 ◽

2010 ◽

Vol 13 (3) ◽

pp. 54-66

Author(s):

Phuong Thi Thanh Nguyen ◽

Phuoc Van Nguyen ◽

Anh Cam Thieu

Keyword(s):

Wastewater Treatment ◽

Industrial Wastewater ◽

Utilization Rate ◽

Organic Loading ◽

Treatment Efficiency ◽

Research Results ◽

Loading Rates

This study was performed to evaluate the efficiency of tapioca processing wastewater treatment using aerobic biofilter with variety of biofilter media: coir, coal, PVC plastic and Bio - Ball BB15 plastic. Research results in the lab demonstrated all four aerobic biofilter models processed can treated completely N and COD which COD reached 90-98% and N reached 61-92%, respectively, at the organic loading rates in range of 0.5, 1, 1.5 and 2 kgCOD/m3.day. The results identified coir filter was the best in four researched materials with removal COD and specific substract utilization rate can reach 98%, and 0.6 kg COD/kgVSS.day. Research results open the new prospects for the application of the cheap materials, available for wastewater treatment.

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