Transfer Routine

Can someone give me an example of a transfer routine which is written in the InfoObject

The object is 0BATCH which is a string of characters which in some cases I want to replace one of the characters. My problem is looking up the Batch Number itself. The details are:

1) I have a Batch Number and want to replace one of the characters in the Batch number and replace it with the # character

2) The character that I want to replace will be anything with an ASCII value less than 32

3) The ASCII code for # is 35