Hi Asif,
What do you mean by retirement value not available?
If I assume that these assets don't have any retirement value,you can use ABAVN t-code to do the retirement.
You can do the mass retirement by creating a simple LSMW of above transaction code.
Alternatively, you can follow below link on which AR01 worklist method is explained in detail for mass retirement.
Usage of Worklist Functionality in Asset Accounting-Part I
Regards,
Vivek
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