3D instance not disposing




I have a site where i have a page on which i am rendering a 3D model. But I am facing a very strange behaviour i.e. when i am redirecting from 3D page and come back again, my 3D model instance is duplicating i.e. two 3d model is being display. This no. gets increase every time when i do a redirect and come back again on 3D model page.Seems 3d instance is not being dispose and with every redirect it is duplicating or creating one more new instance.
Please refer attached screen shot for reference.

If it is disposing issue then how i can dispose the whole 3d instance and re-initialise the instance again.