Dear, Fatemeh Towhidi

Yes, you can’t use soil or sediment Koc values for sewage sludge.

First let me know that why you are going to use Koc

Second, what about composition of your sewage/sludge? Is it close to the composition of soil? What about the content to organic matter (OC) of your sewage sludge?

If its composition is close to the soil and (OC) is not much higher, you can use soil Koc and OC to find Kd for your sludge. But uncertainty of this Kd is very high because other component to sewage may effect on Kd

So, best thing is find out the experimental Kd for your sewage/sludge

Piyal

Sewage sludge are mainly organic matter (>80%) but soils are usually

Mr. Piyal and Dr. Henrik, thank you for your replies, 

I have both primary ( low organic matter) and secondary sludge (high organic matter). my compounds are Chlorophenols as well as pharmaceuticals. Since Kd is not available, Im trying to find them experimentally though I thought I can use Koc for them and then compare with experimental Kd to see how well the correlation will be. 

How do you think about it?

Thank you in advance

yes, your idea is good. if you need further help (to find Koc) let me know I will help you.

Regards

Piyal 

There are some reports mentioning Koc which I will use them, also would like to try EPIsuite which seems can predict Koc. 

Nice of you. Will definitely pm you in case I have any problem. Thank you so much Mr Piyal,