One great way to get rid of writer’s block is to read other books and articles on your subject.
For non-fiction, you should have 20-50 books on the subject you are writing about. And you should have some similar books even if you are writing fiction. Look at what others have done; not to copy them, but to see how you can do it better. Write down the mistakes they made and what you would do differently. And guess what, you are writing again.