$a = $_SESSION['id'];
  $ob = Mage::getModel('management/file')->getCollection();
        $res = $ob->addFieldToFilter('task_id',$a);
    //  $res = $ob->addFieldToFilter('comment_id',$id);
        //$img = "";
        foreach($res as $val)
        {
            $img = $val->getFile();
            //$name = $val->getfilename();
            $Type = $val->getType();
            $type = "Content-type: ".$Type;
            header($type);
            print_r($img);
        }

<img height="30px" width="30px" src="imgs.php?Id=<?php print_r($id);?>"/>