Polymeric Ferric Chloride Research Articles

Enhanced purification of hospital wastewater by a novel ferrate(VI) flocs recycling process

Traditional Fe(VI) treatment process does not fully utilize the fresh iron flocs. This study proposed a novel Fe(VI) flocs recycling process. The flocs were recycled into the front-end reactor and the flocculation effluent further reacted with Fe(VI). Compared with Fe(VI) alone, the CODCr of the secondary effluent of hospital wastewater decreased from 74.9 to 59.4 mg/L and TP decreased from 0.36 to 0.10 mg/L at the dosage of 20 mg/L Fe(VI). However, the enhanced removal of NH3-N and TOC by the flocs recycling process is limited. The Fe(VI) flocs recycling process also strengthened the removal of luminescent bacterial acute toxicity, from 0.52 ± 0.01 in secondary effluent to 0.17 ± 0.01 mg-ZnSO4/L. Compared with polymeric ferric chloride and ferric chloride (FeCl3), Fe(VI) showed the best performance on purifying wastewater in the flocs recycling process. Compared with FeCl3, the CO bond contents in flocs from Fe(VI) changed more obviously. Flocs from Fe(VI) have a smaller average particle size than those from FeCl3, which may result in better adsorption capacity of Fe(VI) flocs. In conclusion, the flocs recycling process not only taken full use of the Fe(III) flocs and reduced the iron sludge, but also strengthened the purification of the wastewater without additional Fe(VI) dosing.

Innovative polymeric inorganic coagulant-flocculant for wastewater purification with simultaneous microbial reduction in treated effluent and sludge

The current work introduces polymeric inorganic coagulant-flocculants; poly-ferric chloride (POFC) which prepared using iron-containing waste. Different POFCs were produced according to Fe/basicity ratio. Likewise, the efficiency of POFC for purification and microbial decontamination of domestic wastewater was evaluated using various doses of POFC coagulant-flocculants. The solid content of the prepared POFCs was ranged from 11.1 to 29.9%, and density was varied from 1.13 to 1.24 kg/L with the varying iron/basicity ratios. Analyses results of XRD, FTIR and SEM confirm formation of a new inorganic polymeric ferric chloride that it is not assumed simple mixture of components. Moreover, the prepared POFCs showed coagulant-flocculant characteristics; therefore it is employed for treating wastewater without introducing organic polymer. Both POFCs coagulant-flocculants showed removal efficiencies of 99, 99 and 91% for total suspended solids (TSS), turbidity and chemical oxygen demand (COD) from domestic wastewater. Also, a complete deactivation of the tested waterborne species in wastewater was achieved at 100 ppm dose of POFCs. At POFC dose of 150 ppm, it was found that the anaerobic microbes and sulfate-reducing bacteria in sludge were reduced by 99.9 and 98%, respectively. The deactivation anaerobic micobes and sulfate-reducing bacteria in the produced sludge by using POFC will result in odor reduction generated from sludge. Moreover, the integration between POFC-based coagulation and rapid sand filtration (RSF) lowers POFC dose use and showed a good efficiency for domestic wastewater purification and microbial decontamination. Finally, POFC-based treatment aids in the decrease organic and bacterial load that results in reducing disinfection use and declining disinfection by-products levels. Moreover, POFC-based treatment/rapid sand filtration is considered a well-located cost-effective train for purification of domestic wastewater and microbial decontamination in treated effluent and sludge and which can be reused for safe agricultural purpose.

Sustainable solutions for urban wastewater management and remediation

Sustainable development with environmental protection is one of the greatest challenges of the 21st century. There is a growing consideration of the sustainable development and environmental management in new industrial cities. Investigational aspects were carried out in El Obour city as Egyptian new industrial city for estimating the current wastewater problems as well as applying mitigation actions. Industrial inventory was constructed for selected industrial sectors as food, chemical and textile sectors including water consumption, materials and energy resources. Wastewater samples from different factories and lifting stations were analyzed for estimating the industrial effluent loads. The obtained data revealed that food sector represents the highest load for BOD and TSS with values of 80 ton BOD/day and 2.33 ton SS/day. For selected industrial sectors, cost-effective technology is applied to reduce the loads on the centralized wastewater treatment plant (WWTP) as well as on the lifting stations. Inorganic polymeric ferric chloride (POFC) coagulant gives higher removal efficiency for TSS and COD without pH control. Moreover, the chemicals cost for treating wastewater is reduced by 40 % with using POFC instead of conventional coagulants.

Experimental Studies on Enhanced Coagulation of Tail Water

Traditional wastewater treatment methods can no longer remove effectively nitrogen and phosphorus that are the direct murderers of water eutrophication hazard. Enhanced coagulation method was adopted to improve the treatment effect by dosing suitable coagulants and coagulant aids. The raw water was from the reclaimed water in a University. TP and ammonia nitrogen removal of the water had been researched through an enhanced coagulation process with dosing ferric chloride, aluminum sulfate, polymeric ferric chloride, and poly-aluminum chloride (PAC) in this study. The coagulants effects were estimated by determining the removal rate of ammonia nitrogen, TP, COD and turbidity. When dosing the raw water with 80 mg/L PAC, the removal rates of ammonia nitrogen, TP, COD and turbidity are respectively 6.12%, 67.79%, 26.21%, 85.41%. The experimental results can be used as a reference of water treatment in the reclaimed water station.

Characterizing membrane foulants in MBR with addition of polyferric chloride to enhance phosphorus removal

The effect of polymeric ferric chloride (PFC) addition on phosphorus removal and membrane fouling were investigated in an anoxic/oxic submerged membrane bioreactor. The total phosphorus concentration in effluent averaged at 0.26mg/L with PFC addition of 10–15mg/L, while the rate of membrane fouling increased 1.6 times over the control MBR (without PFC addition). Three-dimensional excitation–emission matrix fluorescence spectroscopy and Gel Filtration Chromatography analysis indicated that soluble microbial byproduct-like materials and large molecules (MW>100kDa) were one of the main contributors of biofouling. Fourier transform infrared spectrum confirmed that the major components of the cake layer were proteins and polysaccharides materials. Scanning electron microscopy demonstrated that membrane surfaces were covered with compact gel layer formed by organic substances and Energy Dispersive X-ray analysis indicated that ferric metals were the most important inorganic pollutants. Consequently, soluble organic substances and dose of PFC should be controlled to minimize membrane fouling.