hello richardg,
you can use it , as long as you do mix it with other stuff. You could buy some old straw and mix it with that or you could get some farmyard manure or horse manure , as long as there is plenty of straw in it !! , and mix it with that . You can use it in the compost bins ( well mixed ) or you could just mix and pile it in situ ...it will rot down fine either way . You just need to make sure you mix it well . If you use just straw, you will need to make sure you soak the straw well first , then mix it with the grass cutting sludge. It is heavy work doing the mixing , but it doesn't need to be done all in one go . So take care and don't overdo things . It is very easy to put your back out doing this....Hope that helps a bit...
cheers
Russ