Studies of Humic Acid Removal from Aqueous Systems by Using Polymeric Membrane Ultrafiltration Process

Abstract

This paper proposes to investigate in detail the behavior of polymeric membranes ultrafiltration process uses in the retention of humic acid from aqueous systems. Nowadays, the aqueous systems (contaminated water and/or wastewater) resulting from various domestic and industrial activities contain many contaminants, some of them increasingly dangerous to the environment. Laboratory testing of membranes in the ultrafiltration process as well as their experimentation with different chemical compounds is essential because it is important to know how they can be eliminated before they cause a negative impact. Testing of polymeric membranes consists in carrying out the process of ultrafiltration of aqueous systems containing humic acid over a set time, following the variation in time of the volume of permeate obtained as well as the influence of process parameters. Following the investigation of the ultrafiltration process of the water through the polymeric membrane, it was found that the formation of the humic acid layer on the surface of the membrane that favors fouling is delayed, after many hours of operation, due to both the internal fiber structure which offers advantages to this type of membranes as well as high efficiency of humic acid retention. Experimental results showed that the humic acid retention rate increased by up to 37% as a result of the double decrease of the conductivity value in the permeate samples from about 600 mS/cm to 373 mS/cm and the temperature being continuously increasing, from 22.5 at 25oC over 5 h influenced the entire ultrafiltration process. The full process approach as well as the expression and interpretation of the results will be detailed in this paper.

Surface Water Quality Assessment from a Mining Area. Case study, Groapa Burlacu lake, Targu Ocna, Romania

“…What leads to the decrease of the quality of the water both the surface and the underground are the different mining activities, industrial and municipal, the wastewater discharge, the improper storage of the different categories of waste. For a more efficient management of water quality it is necessary to monitor it regularly [1][2][3][4][5][6][7][8][9][10].…”

Treatment Study of Brook Water by Using the Ultrafiltration Pilot with Polymeric Membrane

“…At the same time, 14 chemical elements present in the waste water were analyzed and after determining the concentration of the heavy metals after the completion of the experiment it can be confirmed that the use of polymeric membranes is and will be a viable solution for the purpose of protecting the environment and health.Industrial areas, regardless of the intensity of their activities, generate huge quantities of wastewater that contain pollutants from the most "friendly" with the environment to the most dangerous [1][2][3][4][5][6][7][8][9][10][11]. A quite important part of the industries generates waters that have in their composition high concentrations of heavy metals, such as: chromium, nickel, cadmium, manganese, iron, lead, etc., some being retained through the purification processes of the stations thus designed, others bypassing them, being a threat to aquatic life as well as to human health [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28].In addition to the conventional methods of purification, the membrane technology has several advantages because the membranes, regardless of their type, have lower costs, are easier to exploit, in addition, they offer the possibility to separate the compounds for future use [29][30][31].The application of membranes in the processes of separation of heavy metals can have a rather high efficiency, but this efficiency depends very much on the working parameters of the experiment, such as the pH of the solution, the concentration of metals in the solution, the pressures that are created over time, other added solutions, operating time, etc. [32-34].Some studies have shown a decrease in the rejection of heavy metals as the pH value decreases, which meant a decrease in the absorption of metal ions [35]…”

“…Industrial areas, regardless of the intensity of their activities, generate huge quantities of wastewater that contain pollutants from the most "friendly" with the environment to the most dangerous [1][2][3][4][5][6][7][8][9][10][11]. A quite important part of the industries generates waters that have in their composition high concentrations of heavy metals, such as: chromium, nickel, cadmium, manganese, iron, lead, etc., some being retained through the purification processes of the stations thus designed, others bypassing them, being a threat to aquatic life as well as to human health [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28].…”

Hydrodynamic Surface Evaluation of a Polymeric Reverse Osmosis Membrane Using a Crossflow Cell

“…Filtration is a method of separating solid impurities from fluids, following flow through permeable porous media, called filter media or filters [8][9][10][11][12][13].…”