Reliability Test of Closed Crankcase Ventilation System in Industrial NG Lean Burn Engine

This study evaluates the reliability of a Closed Crankcase Ventilation (CCV) system installed on a Caterpillar G3516ULB four-stroke lean-burn natural gas (NG) industrial engine. A year of testing was conducted at a compressor station in Fort Lupton, Colorado, under varying ambient conditions. The CCV system performance reliability was quantified using engine methane (CH4) emissions reduction, oil carryover, oil filtration efficiency, and oil particle size distribution as primary metrics. Two engine configurations were compared over one year: a baseline Open Crankcase Ventilation (OCV) configuration and the CCV configuration. Results demonstrate that the CCV system reduced engine CH4 emissions by 17% to 37%. Additionally, the system mitigated particulate matter (PM) emissions by collecting oil particles entrained in the crankcase gas (CCG) and recirculating the oil back into the engine crankcase rather than venting the oil to the atmosphere. The analysis showed that the CCV system enhances thermal efficiency by reducing hydrocarbon “leftover” per cycle while simultaneously lowering oil consumption as well as PM emissions. While the system exhibited high filtration efficiency initially, filtration efficiency declined as coalescing filter hours increased. Finally, an economic analysis confirms the benefits and techno-economic feasibility of the CCV system integration under various legislative scenarios.