How & where to claim refund for itc on expenses under gst ?

Friends,

One of our client is Importer of Pulses, which are exempt under GST. He pays various expenses such as Loading, Unloading, CMC Charges, Examination Exps, Delivery Charges & Agency Charges etc related with import of goods.

So, where to claim refund for such GST paid on Expenses ? Because the firm does'nt have any taxable goods and hence he can not set-off this ITC. He has to apply for Refund.

Pl Help.

T & R

K P Bhanushali