Hide the Recycle Bin link on the left hand bar for non-admin users in SharePoint 2010

look for this tag on default.master or the custom master page you are using:

<SharePoint:SPLinkButton runat="server" NavigateUrl="~site/_layouts/recyclebin.aspx" id="v3idNavLinkRecycleBin" ImageUrl="/_layouts/images/recycbin.gif" Text="<%$Resources:wss,StsDefault_RecycleBin%>" PermissionsString="DeleteListItems" />
and the tag

<SharePoint:ClusteredSPLinkButtonrunat="server"NavigateUrl="~site/_layouts/recyclebin.aspx"ImageClass="s4-specialNavIcon"ImageUrl="/_layouts/images/fgimg.png"ImageWidth=16ImageHeight=16OffsetX=0OffsetY=428id="idNavLinkRecycleBin"Text="<%$Resources:wss,StsDefault_RecycleBin%>"CssClass="s4-rcycl"PermissionsString="DeleteListItems" />
Replace the PermissionsString property in above tags from "DeleteListItems" to "ManageWeb"