At the LHC top quarks will for the first time be produced abundantly and with very large transverse momenta. For hadronic decays of top quarks at large pT the three jets merge into a single jet: a top monojet. Identification of these objects among the overwhelming QCD di-jet background requires the development of specific experimental techniques. In this note the use of flavour tagging algorithms based on the B-hadron lifetime for the identification of top monojets will be explored
