This is noting universal that can be decided for your unknown sample. The best would be do a TS analysis for your specific samples.

It mainly depends on the type of digestion lagoon or chamber you use but as you do not want to lose gas, water evaporation will be low. It further depends on how old the manure was and how much straw it contains. Over the thumb, dry matter content of manure digestate is 10 to 15%.

Colleague

To determine dry matter, let say 100 g of sample at 60 C degree for 40 h in air circulation oven, could be ok. Regards

sure, nothing is better than analyzing it for each of your samples.

What I'm saying is, I'm working on a study for an anaerobic digester with a retention time of 30 days, and the raw material is only cow dung, and I'll add water to the fresh dung by a 1:1 ratio lt/Kg dung.

and I want to know approximately the water content of my effluent so I can design the dryer of my slurry to produce organic fertilizer.

Dear Isam A.AZIZ Attar

I hope you are doing great. You mentioned that you are going to add water to fresh cow dung at 1:1 ratio, but the important thing here is that the "fresh cow dung" contains up to 80% water in it, depending on type of the cattle, what it eats, and how the manure is collected from the cattle farm. So that you should initially measure the water content of the dung. Afterwards, by adding more water, you will exactly know the amount of water in your anaerobic digester. If you wanna calculate the remaining water content in your AD digester, you should know the operation temperature of the digestion process at first which good be 10-60 centigrade degrees. Then you can calculate the amount of remaining water using energy balance equations related to sensible and latent heat flows. Another option could be measuring the water content of the produced digestate or slurry, if you have a continuous anaerobic digester. So by having the percentage of the water in the digestate, you could estimate the approximate mass percentage of the remaining water in the digester.

Best