I ask this question on behalf of a housemate who asked me.
I am aware that the Divine Liturgy can be celebrated only once on an altar between midnight and midnight of one day, and that a priest can (con)celebrate the Liturgy only once in the same span of time. But can a layperson RECEIVE Holy Communion twice in one day (again defined as midnight to midnight)? Citation of canons or rules from the Typikon are highly recommended to back up your assertions.
Personally, I don't think so, since the Divine Liturgy is the work of the entire assembly--bishop/priest and faithful--and not just the work of the clergy. Thus, even the laity can and should in this sense be considered concelebrants and not just receivers of the Holy Mysteries. But I don't know for certain how the canons/Typikon understand this, and I don't want to push forward my reasoning as authoritative.