How to print only src path of taxonomy image
A quick look at a download of the current version of the module (1.7) shows that there is a function based on the $tid that returns a lot of formatted and unformatted information:

/**
 * Function to get an image object with more useful data for custom formatting.
 * @param
 *   $tid - the term tid.
 * @return
 *   image object.
 */
function taxonomy_image_get_object($tid, $recursive = NULL)


with one of the things being returned being the url to the image.  Assuming this function exists in your version, would this work for your use case?  If so, there is even a helper function available as well:

/**
 * Function to get a url for an image, for use in css, html or other client-side code.
 * @param
 *   $tid - the term id
 * @return
 *   The url string.
 */
function taxonomy_image_get_url($tid) {
  $image = taxonomy_image_get_object($tid);
  return $image-&gt;url;
}