"Development of microbial treatment of ret liquor generated in a coir ...

2.2.9.a. The enrichment system.
The pre-enrichment system was set up in a 30L capacity plastic basin
in which a submerged sand based filter bed was set up in the pattern of
biological filter. Water in the filter bed was circulated using an air lift pump
as depicted in Fig .1. The basin was filled with ret liquor with the
polyphenols regulated to lmg. ml-' .Water and sediment samples from
various retting grounds were collected and introduced in to the to the final
system in l Ornl and l g aliquots respectively. Nutrients such as NH 4Cl
concentration of 1% NH4N03 to the final concentration of 0.2% were
supplimented, pH adjusted to 7.5+ 0.2 with IN NaOH and the air lift pump
in the packed bed reactor was operated. The system was monitored for the
drop in pH and polyphenol content.
As the pH dropped it was adjusted to neutrality with 1N NaOH and as
the polyphenol content was brought down to less than 0.1ppm a part of the
ret liquor was drained off and replaced with fresh ret liquor and the process
continued until the system got conditioned. On conditioning the system
removal of polyphenol from the ret liquor was attained at the rate of
lrng.ml" per day. Two such systems were developed and maintained for the
isolation ofbacteria and fungi for the envisaged ret liquor treatment system.
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