WHRB waste heat steam boiler

The WHRB waste heat steam boiler turns the heat of hot exhaust and flue gases, which would otherwise escape through the stack, into steam. As the gases pass through the tubes of the fire-tube boiler, they release their heat to the water under pressure. TSB Energy builds these boilers for up to 20 000 kg/h of steam (up to about 14 000 kW) at up to 25 bar. With no fuel or burner of its own, the boiler emits no COx, NOx or SOx at the user's site, and the recovered energy reduces fuel costs and the carbon footprint.

The high-pressure, fire-tube, cylindrical boilers are built vertical or horizontal; design and manufacture follow EN 12953, PED 2014/68/EU, TRD and ASME VIII Div. 1. Shell and tube plates are P355GH (EN 10028-2) and boiler tubes P235GH or P265GH (EN 10216-2); for biogas and other corrosive gases, the shell is made of AISI 304 or 316 and the tubes of AISI 304, 316 or 316Ti stainless steel. Narrower tube diameters and a longer boiler body accelerate the flue gas at an ideal back-pressure.

The boiler comes on a single skid, ready to run, and only needs power, feedwater and the steam line to be connected. Suitable heat sources include high-temperature exhaust from furnaces, kilns and dryers, boiler flue gases and exhaust from power plants. For the investment to pay back, the site needs a process that can use the recovered heat efficiently, so TSB recommends a thorough feasibility study first. Every 20 °C recovered from the flue gas going to the stack raises the efficiency of the equipment by 1 %.