Calcium reactor design.

[DJ88]

Rob,

You'll get dead areas in a round one too.

With the media not being a consistent density throughout the reactor the water will want to find the easiest way to the area of lowest pressure. ie where your pump is sucking water in. The easiest way to do this for the water is to run down the sides of your reactor agasint the acrylic. It is a smooth straight surface for it to run next to. So basically it shouldn't matter too much what shape your reactor is. This is called a skin effect in electronics. I presume it will be a similar effect in this situation. The water woudl rather run on the outside of the tube than the inside de to friction and resistance to flow.

It is this principle that in a high flow effluent situation that makes a second chamber in a reactor useless. If it is a slow flow reactor, say 80 ml/min or so the water will flow somewhat through all the media in the one pass it has in the second chamber. It has more dwell time in the media. But once you start getting the flow rate high enough all the water will want to do is follow the easiest route out of the tube. And that is against the sides of the reactor. Now if you were to add a recirculation pump on that second chamber you'd change that by forcing more of the effluent to run towards the center of the reactor.

I think a square reactor would work juts fine. It's just a heck of a lot easier to work with the round tube than piecing the facets together to make a square one.

In addition the reason it is a good idea to change your media regularly whether you used it all or not and not just "top it up" is that once you start breaking the media down it will form a finer and finer particle size. In time this will form a think paste like clay in your reactor and really affect the flow of effluent through the reactor.

[ 13 May 2002, 22:17: Message edited by: DJ88 ]