Removal efficiency of invertebrates in the filtrate of biologically activated carbon filter with sand bed

Activated carbon filter is often used as the pretreatment process of nanofiltration or reverse osmosis membrane system, especially when the content of organics and free chlorine in influent water is high. However, a lot of microorganisms often rapidly reproduce in the activated carbon filter after continuous operation, resulting in a large number of bacteria in the effluent. So when the activated carbon filter was used as pretreatment of membrane systems, membrane fouling caused by biological contamination often occurred. The objective of this paper was to discuss how to effectively control the activated carbon biological contamination. Three different control methods—water backwashing, hot alkali treatment and ultrasound treatment were compared. Results showed that ultrasound treatment was the most effective. A relatively high removal efficiency of biomass (above 90%) was obtained when 40 kHz ultrasound was applied at 90 W for 20 min. Bacterial count in the effluent can be decreased from 3.90×104CFU•mL-1 to 8.5×103CFU•mL-1. After 3 days of continuous operation, bacteria count increased from 8.5×103CFU•mL-1 to 4.06×104CFU•mL-1. After ultrasound treatment, the removal efficiency of CODCr increased from -386.3% to 73.8%.

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Application of Aerated Activated Carbon Filter for Advanced Treatment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.864-867.2090 ◽

2013 ◽

Vol 864-867 ◽

pp. 2090-2095

Author(s):

Feng Xun Tan ◽

Rong Zhen Zhou ◽

Dao Ji Wu ◽

Ning Wang ◽

Nan Lu ◽

...

Keyword(s):

Activated Carbon ◽

Removal Efficiency ◽

Treatment Effect ◽

Polluted Water ◽

Advanced Treatment ◽

Water Plant ◽

Activated Carbon Filter ◽

The Impact ◽

Carbon Filter

The objective of this research was to study the treatment effect of micro-polluted water usingconventional activated carbon filter(CACF) andaeration activated carbon filter(AACF), test the effect of backwashing on the performance of carbon filters, and provide a reference for water plant upgrading. The removal efficiency of pollutants and the impact of backwash of AACF was studied and compared with CACF. The results showed that, with an influent turbidity of 0.67 versus 0.44NTU, CODMnof 2.48 versus 2.74mg / L, UV254of 0.045versus 0.045cm-1and NH4+-N of 0.15 versus 0.11mg / L, the removal effect of turbidity, CODMn, UV254,and NH4+-N are 36.19% versus 33.67%, 30.63% versus 21.53%, 23.06% versus 26.57% and 34.34% versus 19.62% . AACF improved the treatment of CODMn,and NH4+-N by 26.66% and 60%. Backwash is found to enhance the performance of AACF on CODMnwith the removal efficiency increases from the 25.82% to 29.75% after 2 hr backwash, and stabilizes at approximately 30% at the consequent 6 hrs; Backwash decreases UV254removal from 17.51% to 16.64% after 2 hr backwash, increases it to 19.64% to after 4 hr treatment, and drops to 13.44% after 8 hrs. Additionally, backwash has no significant effect on NH4+-N.

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Chemical-Free Greywater Treatment Using Aeration, Sedimentation, Followed by Granular Activated Carbon Filter (GAC) -A Case Study of Baghdad city household

Journal of Engineering ◽

10.31026/j.eng.2020.10.05 ◽

2020 ◽

Vol 26 (10) ◽

pp. 66-79

Author(s):

Marwa M. Ali ◽

Nawar Omran Ali ◽

Mahdi Shanshal Jaafar

Keyword(s):

Activated Carbon ◽

Removal Efficiency ◽

Irrigation Treatment ◽

Treatment Plant ◽

Oxygen Demand ◽

Granular Activated Carbon ◽

Water Source ◽

Small Scale ◽

Activated Carbon Filter ◽

Carbon Filter

Greywater is a possible water source that can be improved for meeting the quality required for irrigation. Treatment of greywater can range from uncomplicated coarse filtration to advanced biological treatment. This article presents a simple design of a small scale greywater treatment plant, which is a series of physical and natural processes including screening, aeration, sedimentation, and filtration using granular activated carbon filter and differentiates its performance with sand filter. The performance of these units with the dual filter media of (activated carbon with sand) in treatment of greywater from Iraqi house in Baghdad city during 2019 and that collected from several points including washbasins, kitchen sink, bathrooms, and laundry, was recorded in terms of removal efficiency of particular pollutants like Turbidity 94%, chemical oxygen demand (COD) 93%, and oil 91%. Dual filter was the most effective filter for decreasing these pollutants, while sand indicates the lowest removal efficiency. In general, granular activated carbon media seemed to be the most proper medium to improve greywater quality for reaching the quality of irrigation within the terms of organic matter decrease. Accordingly, this technology may be reliable for greywater treatment in a residential area.

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Validation of chemotherapy drug vapor containment of an air cleaning closed-system drug transfer device

Journal of Oncology Pharmacy Practice ◽

10.1177/10781552211030682 ◽

2021 ◽

pp. 107815522110306

Author(s):

Galit Levin ◽

Paul JM Sessink

Keyword(s):

Activated Carbon ◽

Closed System ◽

Membrane Filter ◽

Drug Transfer ◽

Glass Vessel ◽

Air Cleaning ◽

No Release ◽

Activated Carbon Filter ◽

Carbon Filter ◽

Transfer Device

Purpose The purpose of this study was to test the efficacy of ChemfortTM, an air filtration closed-system drug transfer device to prevent release of chemotherapy drug vapors and aerosols under extreme conditions. The air cleaning system is based on the adsorption of drug vapors by an activated carbon filter in the Vial Adaptor before the air is released out of the drug vial. The functionality of the carbon filter was also tested at the end of device’s shelf life, and after a contact period with drug vapors for 7 days. Cyclophosphamide and 5-fluorouracil were the chemotherapy drugs tested. Methods The Vial Adaptor was attached to a drug vial and both were placed in a glass vessel. A needle was punctured through the vessel stopper and the Vial Adaptor septum to allow nitrogen gas to flow into the vial and to exit the vial via the air filter into the glass vessel which was connected to a cold trap. Potential contaminated surfaces in the trap system were wiped or rinsed to collect the escaped drug. Samples were analyzed using liquid chromatography tandem mass spectrometry. Results Cyclophosphamide and 5-fluorouracil were detected on most surfaces inside the trap system for all Vial Adaptors without an activated carbon filter. Contamination did not differ between the Vial Adaptors with and without membrane filter indicating no effect of the membrane filter. The results show no release of either drug for the Vial Adaptors with an activated carbon filter even after 3 years of simulated aging and 7 days of exposure to drug vapors. Conclusions Validation of air cleaning CSTDs is important to secure vapor and aerosol containment of chemotherapy and other hazardous drugs. The presented test method has proven to be appropriate for the validation of ChemfortTM Vial Adaptors. No release of cyclophosphamide and 5- fluorouracil was found even for Vial Adaptors after 3 years of simulated aging and 7 days of exposure to drug vapors.

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