Re: bioballs and ceramic rings

[leebc at sbs_sumibe.co.jp]

With all the talk of bioballs and ceramic rings, it reminded me of my
university days.  I studied Chemical Engineering.  I thought that I would
have nothing more to do with those balls and rings after I decided not to
work in the chemical industry.

In the chemical industries & water treatment processes, there are 1001
designs of balls and rings (they are called packings).  They are mainly
designed to make the largest possible contact area between 2 fluid mediums
or a fluid medium on a media adsorbed on the packing.  The packings are
very elaborately designed and tested first of all for liquid flow and also
for contact area.

In my opinion, bioballs are best used for wet/dry trickle type filters.
This type of design is the best in terms of aeration.  It is designed for
the water to be distributed when it's trickling down.  I thought that
bioballs will not be particularly effective when used fully submerged.
However, bioballs need very little cleaning and virtually have unlimited
lifespan.

The ceramic ring on the other hand is good in terms of surface area.  These
rings have varied porosity depending on the material.  I have came across
Sera Siropax which is extremely porous and has very high surface area per
unit volume.  These type of design is good for canister type filters where
the water fully fill the pores.  However, these rings have limited lifespan
as these pores will get clogged.  These rings needs to be cleaned
periodically and, in the long run, the effectiveness of these rings will
decline as some of the pores will become permanantly clogged.

Hmmm... afterall, those torturous hours in the lectures did not go to
waste... :-)

BC (Singapore)