distillery slops color problem 1

[iski]

hi!

does anybody had the experience to reduce the color of distillery slops? i have observed systems using anaerobic and aerobic treatments effectively reducing the BOD and other nutrients, but not the color.

thanks in advance

 

[camabee]

What about Ozone? Effective for colour removal, cost effectiveness very dependant on scale and value you can place on colour removal.

 

[iski]

thanks for the info.

have you happen to actually apply this on distillery slops? do you some data which i can already use?

thanks again.

 

[kenvlach]

I have some experience in treating dyes.
Besides the ozone method already mentioned, hypochlorite is commonly used to destroy organics.
For automated setup, use sodium hypochlorite liquid w. ORP controller & metering pump.
For small/batch setup/occasional use, calcium hypochlorite 65% granules added manually may be cost effective.

Hydrogen peroxide can also be used, and it doesn't have odor or residual Cl- like hypochlorite, but it is slower acting and sometimes ferrous sulfate is added as a catalyst (Fenton's Reagent).

For a nice, clean, non-chemical* method, consider electrocoagulation. The fluid is passed between a bank of iron or aluminum plates of alternate charge, and generated ions do the decomposition. Find a local vendor for a better explanation and a demonstration using a portable unit.
*some Al or Fe does dissolve.

 

[iski]

thanks for the info and fast response

 

[Modak]

Dear sir,
As regards distillery slop colour removal, we have developed reverse osmosis based solution. Rochem Separation Systems India P. Ltd., offers a special system usefulfor high TDS & COD application, which can process either raw distillery slop or slop after biogas generation to recover colorless water to the extent of 70% of the volume & the balance is to be composted by a suitable agro residue. It is very successful in India & a pilot unit of 90m3/day capacity is working very fine for past one year. Another unit of 260m3/day capacity will be commissioned by end June 03.for more details please contact me (Dr. H. M. Modak on e-mail id: tejashri@vsnl.com
Rgds, Dr. Modak

 

[Shamil]

I suppose you are dealing with grain as a raw material. A dark color product you do not wish comes out as a result of caramelization (Milliard) reactions, that are taking place in the jet cooker, mash column and the dryer. Dark color means poor quality of this product as an animal feed.
The DDGS color you get depends on the cooking and drying temperatures and the amount of residual sugars in the beer (the higher-the darker). There is no way to improve the quality by any further treatment. You can only prevent.
To obtain nice light color (and therefore, good nutritional quality)you have to consider lowering the cooking temperature, making sure the fermentations are complete and the residual sugars are low. The most radical solution is to put under vacuum the mash column and the thin stillage evaporator to keep stillage processing temperatures under 80 deg C.