Del. Code tit. 9, § 8779

After satisfying the tax due and the costs and expenses of sale from the proceeds of sale under this subchapter, the amount remaining shall be paid at once to the owner of the land, or upon the refusal of the owner to accept the same, or if the owner is unknown or cannot be found, the amount remaining shall be deposited in some bank in the county either to the credit of the owner, or in a manner by which the fund may be identified.