vertical structure Oil gas boiler has a natural circulation system with a boiler shell. According to the height between the decks and the way of the host engine discharge the gas.The Oil-fired part and exhaust-gas part can work together or separately. The steam capacity of the Oil-fired part is 0.3t/h~4t/h, the maximal working pressure is 0.7Mpa; the heating surface area of the exhaust-gas part is decided by the discharged smoke of host engine.