and gas oil fired energy input 13.1 MW fuel input natural gas 1206 kg/hr, gas oil 1097 kg/hr, air flow 14,000 Nm3/hr, flue gas flow natural gas 14,150 Nm3/hr, gas oil 14,866 Nm3/hr, heating surface area furnace 60sqm, screen 2.6sqm, evaporator 33sqm, walls of convection part 25sqm, economizer 1 683sqm, economizer 2 78 SqM, total 881 SqM. 2 x 20 t/hr boilers working in tandem, the boilers are all welded water tube boiler with natural water circulation, built as a vertical and self-contained construction in which the downcomers form the supporting columns, vertical expansion of the boiler is free upwards, boiler has a radiation part, a convection part and a detached economizer, the radiation part is to reduce the flue gas temperature before the convection part, the radiation part is built as an all-welded membrane wall section on the sides, top and partition wall, the economizer is in the back of the convection part and is made with horizontal tube coils, these are a nest of pipes consisting of 14-tube lines of each 28 tubes, the evaporator is made with diagonal tube coils, which are a nest of 6-tube lines of each 28 tubes, the detached economizer is built as a four sided casing tower in which are placed horizontal convection heating surfaces, final condensing (Ceecon) economiser which preheats the boiler feed water. Main item consists of: (2) 20 t/hr (design load, 100% Maximum Continuous Rating) Ansaldo Volund water tube boilers, design pressure 91 bara, normal working pressure 83 bara, feed water temperature 105 deg C, flue gas for dimensioning 16,667 Nm3/hr, flue gas temperature after economizer 139.5 deg C, content of CO2 in flue gas 8.92 volume %, H20 15.84 volume %, O2 2.07 volume %, net calorific value 42.8 MJ/kg (gas oil), 39 MJ/kg (natural gas), Saacke type TSAAYD-135-E3-6275 steam atomizing burner, designed for natural gas or oil, heat input 22,000kg/hr, gas oil output 190-1329 kg/hr, natural gas 163-1631 Nm3/hr, (1) 1640ltr c/steel boiler drum, steam space load 275 m3/m3xh, 1200mm diameter x 3m long, 40mm thick, weld dished ends, (1) Detached in-line fin tube Economizer, manufactured by Emvertec, 683sqm, design pressure 13.5 bar, (1) 316 s/steel Deaerator vessel, manufactured by Cool Technology ltd, design pressure 2 bara @ 105 deg C, operating pressure 0.21 bara (3) Feed water pumps, manufactured by KSB, type HGM-2/15, Other associated equipment include fans, valves, pumps, instruments, control panels, platform between boilers, etc