If you’re scanning large numbers of pages in the library, you’ll need software to help you merge your PDFs.
You can still merge PDFs without having access to a paid tool like Adobe Acrobat.
There are plenty of free online tools that you can use.
MergePDF is a quick, free and easy online tool for combining your documents.
You’ll be limited to files that are 5MB or less for each merge you perform.
Once you finish the merge and download the combined document, the original files will be deleted.
If you find yourself merging PDF files frequently, a free desktop solution might be in order.
Try downloading PDFSam. It will merge and separate your PDF files easily.