A wearable, battery-powered device designed to actively promote continuous diffusion of oxygen (CDO) in a wound to help heal various types of wounds (e.g., arterial, venous, diabetic or pressure ulcers, skin grafts, burns, postoperative or traumatic wounds). It has oxygen (O2) delivery controls with sensors and displays for flow and pressure, and concentrates O2 from ambient air and delivers it through tubing to the wound bed, typically using a wound therapy oxygenator dressing. A battery charger, carrying case, and disposable humidification pack may be included. This is a reusable device.