Effect of Cold Temperatures on Sulfur Denitrification

[LobsterOfJustice]

I have been getting some inconsistent performance from my sulfur denitrator the past few weeks, when in the past I have had pretty solid results. What I mean is that I am intermittently seeing a lot of nitrate breaking through into the effluent, and I keep fiddling with the drip rate in an effort to get low nitrates out of the reactor. The nitrates in the main system have climbed as a result.

This is my first winter in my current house. My sump and equipment are in the garage which can get as cold as the upper 50s - or temporarily dip lower when the garage door is opened for cars going in/out. I have enough heaters in the sump to handle this, but given that the flow through the denitrator ranges from a drip to a trickle, it occurred to me that this flow rate is not enough to maintain temperature inside the reactor. I just did a quick check of the effluent and it read at 64 degrees, and I would assume it could get lower than this at night when the ambient temp is cooler.

Is it reasonable to assume that the microbial activity slows significantly at temperatures around 60* compared to 80*, and/or that swings in the temperature of the reactor could be detrimental to maintaining a stable bacterial population?

 

[Randy Holmes-Farley Verified Community Expert]

I have been getting some inconsistent performance from my sulfur denitrator the past few weeks, when in the past I have had pretty solid results. What I mean is that I am intermittently seeing a lot of nitrate breaking through into the effluent, and I keep fiddling with the drip rate in an effort to get low nitrates out of the reactor. The nitrates in the main system have climbed as a result.

This is my first winter in my current house. My sump and equipment are in the garage which can get as cold as the upper 50s - or temporarily dip lower when the garage door is opened for cars going in/out. I have enough heaters in the sump to handle this, but given that the flow through the denitrator ranges from a drip to a trickle, it occurred to me that this flow rate is not enough to maintain temperature inside the reactor. I just did a quick check of the effluent and it read at 64 degrees, and I would assume it could get lower than this at night when the ambient temp is cooler.

Is it reasonable to assume that the microbial activity slows significantly at temperatures around 60* compared to 80*, and/or that swings in the temperature of the reactor could be detrimental to maintaining a stable bacterial population?

Yes. Most biological processes slow down considerably as the temperature declines, and I see no reason to think it wouldn't happen in a sulfur denitrator.