I agree with the views of Sh.Ganeshan Kalyani, Sir. As per Section 2 (f)(iii) of Central Excise Act one the conditions is that goods i.e. whether waste scrap or bye-product must be marketable. In your case, your waste scrap is not marketable, hence no Central Excise duty is payable. A judgement of Supreme Court and Board's Circular are appended below:-
2015 (322) E.L.T. 769 (S.C.) = 2015 (10) TMI 566 - SUPREME COURT
IN THE SUPREME COURT OF INDIA
A.K. Sikri and Rohinton Fali Nariman, JJ.
UNION OF INDIA
Versus
DSCL SUGAR LTD.
Press-mud arising during manufacture of Sugar, not excisable
Circular No. 730/46/2003-CX., dated 31-7-2003
F.No. 387/S/108/02-JC
Subject : Excisability of Press-mud arising during manufacture of sugar -Adjudication of cases regarding………
Cenvat Credit is also not to be reversed contained in the waste scrap arisen during the manufacture of final product. Relevant extract of Board's circular is appended below:-
F. No. B-4/7/2000-TRU, dated 3-4-2000