CONFERENCE ON WATER, WASTEWATER AND SOLID | Year:2015 | دوره:6 |Papers Count:2

IN THIS PAPER A GENERAL REVIEW ON REMOVAL OF HEAVY METAL FROM WASTEWATER BY DIFFERENT MEMBRANE PROCESSES WASDONE. AS THE MAIN AIM OF THIS PAPER IS TO REVIEW THE APPLICATION OF MEMBRANE PROCESSES IN REMOVAL OF HEAVY METALFROM WASTEWATER, PROCESSES SUCH AS COMPOSITE MEMBRANES, POLYMERSUPPORTED ULTRAFILTRATION, MULTIPLE MEMBRANE, COMPLEXATION –ULTRAFILTRATION, SURFACTANTS-ENHANCED ULTRAFILTRATION, COMBINING PROCESS, MEUF TECHNIQUE, FLOTATIONWITH MEMBRANE WERE REVIEWED.

PURE CULTURE OFHYPHOMICROBIUM DENITRIFICAN DSM 1869 WAS INVESTIGATED FOR BIOLOGICAL DENITRIFICATION.THE BACTERIUM WAS CULTURED IN AN OPTIMIZED MINERAL SALT MEDIUM WITH ACETIC ACID AND METHANOL AS CARBON SOURCES IN 100-MILLILITER FLASKS. THE INITIAL CONCENTRATIONS OF NITRATE WERE 100, 250 AND 400 MG NO3-N/L AND CARBON TO NITROGEN RATIOS WERE 1.2, 2.6 AND 4.0. THE RESULTS SHOW THAT INCREASING CARBON TO NITROGEN RATIO FROM 1.2 TO 2.6, CONSEQUENCES IN HIGHER NITRATE CONVERSIONS. THE MAXIMUM SPECIFIC DENITRIFICATION RATE (2.53 MG/L.H) WAS OBTAINED FOR (NO3-N) 0 CONCENTRATION OF 400 MG/L, CARBON TO NITROGEN RATIO OF 2.6 AND ACETIC ACID AS THE SOLE CARBON SOURCE. HOWEVER, INCREASING CARBON TO NITROGEN RATIO FROM 2.6 TO 4.0 RESULTED IN THE DECREASE OF SPECIFIC DENITRIFICATION RATE. ALTHOUGH REMOVAL OF NO3-N WAS SEEN BY USING METHANOL AS THE SOLE CARBON SOURCE, IT WAS NOT VERY SUITABLE FORHYPHOMICROBIUM DENITRIFICAN TO DECREASE HIGH NO3-N CONCENTRATIONS, AND ACETIC ACID WAS A BETTER ALTERNATIVE. THE RESULTS SHOWED THATHYPHOMICROBIUM DENITRIFICANDSM 1869 IS A GOOD ALTERNATIVE FOR ACTIVATED SLUDGE, WHICH IS WIDELY USED IN WATER DENITRIFICATION PROCESSES. NITRITE ACCUMULATION WAS SEEN IN EXPERIMENTS WITH LOW CARBON TO NITROGEN RATIOS AND THE ONES THAT METHANOL WAS USED AS THE SOLE CARBON SOURCE.