CB&I's Light Olefins Recovery Technology (LORT) recovers the light olefins, specifically the ethylene and propylene that are produced in a Methanol-to-Olefins (MTO) reactor. The Light Olefins Recovery Unit (LORU) also produces several co-product streams, including fuel gas, an ethane and propane stream and a C4 and C5 olefins stream. The C4 and C5 olefins stream is often sent as feed to an Olefins Conversion Unit to boost the propylene production coming from the MTO reactor and LORU by up to 40%. LORT is the leading recovery technology used for MTO reactors. It has been used in twelve units which are in operation or under design, producing over 3.6 million metric tons of ethylene and over 4.0 million tons of propylene. It is known for its high product recovery, low energy consumption, low capital costs and high reliability.
The Light Olefins Recovery Technology recovers more than 99.7% of the ethylene and propylene contained in the MTO reactor effluent thereby maximizing production rates and operating margin. A patented wash system reduces recycle and is recovered using only waste heat from the MTO reactor section rather than separate steam stripping used by competing processes. Energy costs and investment are thereby minimized. A relatively warm operating temperature in the cryogenic section of the recovery unit eliminates the potential of NOx accumulation and NOx gum buildup, making the process inherently safe. Processing the MTO reactor effluent can have high corrosion and fouling potential due to trace components contained in the stream. The design features a number of innovations and the use of special additives to minimize the fouling and corrosion potential, thus leading to high reliability and long operating cycles with limited equipment sparing, which saves capital costs. This high reliability leads to the highest return on investment for the end user.