Page 48 - March 2020 - WT Site

proved to be a tremendous tool in the reduction of Cr (VI) from Biogas produced by the landfills technique and also the anaerobic
industrial effluents and the treatment plants. By this respective digestion systems to methanol using methanotrophs (aerobic
operation, the reduction rates of Cr (VI)/d is near about 4.8 g. CH4-oxidizing bacteria). It is an emerging approach to convert the
Various types of filter media is used to estimate Cr (VI) removal in biogas (which is derived from waste) to liquid chemicals and fuels.
biofilm reactors. The biofilm reactors operated in SBR operating A methanotrophic trickle-bed reactor improved mass transport
mode. Two different materials have been applied in pilot-scale of O2 and enhanced CH4 oxidation to methanol production. The
trickling filters: (a) plastic media and (b) calcitic gravel (Dermou highest CH4 to methanol conversion rates were observed. Using
et al. 2007). optimal operating parameters, methanol productivity showed the
highest (0.9 g/L/d) from the non-sterile TBR (Sheets et al. 2017).
Gravel has high specific surface area. The void space becomes
lesser due to the formation of sediments and pore clogging at the 3. Conclusion
same time. The growth of a thicker biofilm layer has increased
by the plastic media. Due to the thicker biofilm layer avoids the Gradually, pollution regulation becomes stringent for the
pore clogging. It is used for the industrial wastewater treatment betterment of our future. Thus improvement of pollution
because the filter void space is larger. Plastic media indicates the abatement technology is gaining more impetus day by day. Proper
best performance compared to the gravel media at the different management techniques for water treatment can prohibit the water
Cr (VI) concentrations. The rate of Cr (VI) removal in the plastic crisis in near future. Aerobic water treatments gained prodigious
media is greater than gravel media. The plastic media has the importance over the past decades. Low energy consumption,
capability to remove the Cr (VI) 4.23±0.18 for 5 mg/l, 3.62±0.1 easy process, less equipment, potentiality of resource recovery
for 30 mg/l and 3.3±0.08 g for 100 mg/l. In case of other media, etc. makes this process more attractive. Design of appropriate
the removal rates of Cr (VI) were4.11±0.09, 3.52±0.06 and treatment technology, depends on the character of wastewater.
2.5±0.07 g for 5, 30 and 100 mg/l respectively. The main goal of treatment lies on the protection of environment
as well as human health.
Natural ventilation trickling filters (NVTFs) with sponge, zeolite
and ceramsite were utilized in domestic wastewater to treat. NVTFs References
have the capability to remove COD and ammonia. Nitrification
rates (NR), oxygen uptake rate (OUR) and dehydrogenase • Ali HI, El-Azim MMA, El-Rahman MSA, Lotfy AO, Mostafa
enzyme activity (DHA) of microorganism were tested by the MM (2015) The effects of modification for contact stabilization
parameters. Polymerase chain reaction-denaturing gradient gel activated sludge on EBPR. HRBC Journal 11(1):143-149
electrophoresis (PCR-DGGE) analysis was conducted for the • Almuktar SAAAN, Scholz M, Al-Isawi RHK, Sani A (2015)
differences between microbial communities. The differences were Recycling of domestic wastewater treated by vertical-flow
showed between the biofilms on zeolite, sponge and ceramsite wetlands for irrigating chillies and sweet peppers. Agric
(Zhang et al. 2016).The distribution of zeolite was similar with Water Manag 149:1-22
ceramsite than sponge. Zeolite has no superior capability to
remove pollutants or nitrifying bacteria growing. • Attwood D (2012) Surfactant Systems: Their Chemistry,
pharmacy and biology. Springer Science Business Media
Biotrickling filter reactor (BTFR) treatment process is used to
remove Formaldehyde (FA) from polluted air (Fulazzaky et al. • Bassin JP, Rachid CT, Vilela C, Cao SM, Peixoto RS, Dezotti
2016). It can be removed by two successive transfer mechanisms M (2017) Revealing the bacterial profile of an anoxic-aerobic
(1) the formation of formic acid and methanol in the aqueous moving-bed biofilm reactor system treating a chemical industry
phase. It is caused by the reaction of FA with water and hydrogen wastewater. Int Biodeterior Biodegradation 120:152-160
(2) microorganisms are able to metabolise the chemicals-derived • Caluwé M, Dobbeleers T, D’aes J, Miele S, Akkermans V,
FA from aqueous phase after passing through the biofilms. Daens D, Dries J (2017) Formation of aerobic granular
BTFR design and operations have the capability to reduce the sludge during the treatment of petrochemical wastewater.
contaminated air to improve quality of air (Fig. 2). Bioresour Technol 238:559-567

50 Water Today - The Magazine March 2020