Wordpress automatically generate lot of unwanted  tags every where. Even the img tag also wrap by these  t         
        
Wordpress Visual Editor itself create those tags for new lines.
You can try to remove the filter wpautop from the_excerpt or the_content
remove_filter( 'the_content', 'wpautop' );
// OR
remove_filter( 'the_excerpt', 'wpautop' );
Sometimes it doesn't work (Didn't work for me in the past. Not with PHP).
You can try with Javascript/jQuery, place this code after DOM loaded or before the closing 
tag.
jQuery('p:empty').remove();
Will remove all empty  elements  from all over the document.