Try this:
<td id="myTd"><span class="dott active green"></span> Firstname Lastname</td>
$('#myTd').find('span').remove();
solved Remove HTML element from string
Try this:
<td id="myTd"><span class="dott active green"></span> Firstname Lastname</td>
$('#myTd').find('span').remove();
solved Remove HTML element from string