AD plant foam and H2S solutions?

[mugger24]

The pumps on the biolectrics are only small. You could install a bigger one but you would need to be mindful of the o2 levels if pumping to much air. do you have a gas analyser that monitors o2?

 

[mawleymoos]

I Wil try and find out how much oxygen we are putting in! When OMNI lifted the amount, it killed the little air compressor!! So they have now put a fish pump on which seems to be doing fine! But still not sure at what rate it is set at though!!

 

[mawleymoos]

Just looked up! We are putting in about 30ltrs of oxygen per min! Sulphur level is at 300ppm before carbon and 20ppm after, at the moment! Only been settled now for a couple of weeks though as mentioned earlier!!

 

[Chippy]

The plant doesn’t have a gas analyser but we have a mobile one we can test it with. I have to pumps that constantly pump air into the dome but you can’t adjust it. This is screenshot of how much is going in

 

[mugger24]

Fit one of these to what you have now and you will know how much air you are putting in, check to o2 level at present and a quick calc against how much gas you are producing should tell you if you can pump in more air

https://uk.rs-online.com/web/p/flow-sensors-switches-indicators/4487467/

 

[Grass And Grain]

If a cow had frothy bloat I would give it cooking oil and fairy liquid.

Don't know if that helps.

 

[mugger24]

Can you not get advice from the manufacturers? This is quite normal for slurry only AD?

 

[Chippy]

Biolectric haven’t been as helpful as I’d liked......

 

[thesilentone]

Chippy, I think you need some biological testing before you get in a knot. I notice you are adding salt (to reduce H2S) and cooking oil (I assume to liquefy foam). In addition, others are adding stimulants to try to activate the culture.

My advice would to stop doing anything more, slow down the feeding and get the biological results for what you are dealing with.

You supplier will have a testing facility, ask them to give you some priority. soon, you may soon be losing kwhr's and these cannot be replaced !!

To much uncontrolled trial and error going on for my liking (not only you).

 

[Chippy]

Sample being sent tomorrow. Do larger plants have nets to catch the sulphur like mine or do they use something different?
Also we think the iron sulphate were using is making H2S worse and we have now been told it should be Ferric Hydroxide that going in, is this true?

 

[The Son]

Yes we have a net which the bacteria grows on, did you seed the net before closing the tank, ours was sprayed with slurry to get the bacteria growing quickly.

I use liquid ferric chloride, dosing a 2700m3 tank with 15l daily.

 

[Chippy]

Yes mine was sprayed with digestate

 

[The Son]

Are the bugs growing nicely?

 

[Digester Man]

FM Bioenergy have been supporting my biology for the past 18 months and I have found their advice to be excellent. They are affiliated with Schaumann in Germany who would be one of the market leaders in this field. Tim or Adrian would be worth a call

I am no expert by any means but would the sulphur in iron sulphide contribute to h2s?

 

[Chippy]

It certainly looks like it’s contributing to the H2S so I’m just putting a liquid version in now but not sure that’s any better. Anyone know if lots of stirring creates more foam?

 

[thesilentone]

Sample being sent tomorrow. Do larger plants have nets to catch the sulphur like mine or do they use something different?
Also we think the iron sulphate were using is making H2S worse and we have now been told it should be Ferric Hydroxide that going in, is this true?

Firstly it is Iron (ferric) Chloride you need not Hydroxide.

As regards foaming, of course more stirring can cause foaming. In fact , it is one of the most common causes as operators increase stirring to break up a floating layer.

 

[Chippy]

An expert just told me yesterday it’s Hydroxide I should be using and it’s what he sells to loads of AD plant owners [emoji23]
It’s called Active Fe33 made by Omex
I don’t know who to believe now

 

[thesilentone]

An expert just told me yesterday it’s Hydroxide I should be using and it’s what he sells to loads of AD plant owners [emoji23]
It’s called Active Fe33 made by Omex
I don’t know who to believe now

have a read....
file:///C:/Users/User/Downloads/KRONOSecochemTI5_01_EN.pdf


Can't help with the Active Fe, they say very little on the website: http://www.omex.com/product/ActiveFe/

 

[thesilentone]

For the reduction of H2S

Ferros Chloride

specification: http://www.kronosecochem.com/ehome_...ED/$File/TI 1_05_EN_KRONOFLOC.pdf?OpenElement

Hydroxide

Specification: http://www.celticchemicals.co.uk/_documents/Methatec-Detox-S-Standard.pdf

 

[Chippy]

Just found small label on the drum of stuff I got 2 days ago and it’s actually chloride but not reducing H2S yet. How long would you expect 10 litre/day in a 100,000 gallon tank take to have effect?