Solution for loss in process for REM

Hi Friends ,

In one of the IS-Chemical implementation we are facing some problem , We had given REM solution because end product is same . But input raw material will change as per season or rates . There are 3-4 by-products are come in between stages . Major problem is output will varying at each time and loss are also varying each time . Here is make -to stock and continous production . This is pure chemical industry solution . How can i maintain this process . Please suggest .

Regards

Raghu