A method and system is provided for regenerating and cleaning an air-oil coalescer of a crankcase ventilation system of an internal combustion engine generating blowby gas in a crankcase. The coalescer coalesces oil from the blowby gas. The method and system includes regenerating and cleaning the coalescer by intermittent rotation thereof.

A separating module for a ventilation device has a housing that surrounds a separating element designed to separate liquid particles from a gas flow. A line module and a ventilation device with such a separating module and such a line module are provided. The housing of the separating module is designed to be connected to the line module that has at least three geometrically parallel channels and the housing of the separating module has corresponding housing openings to be connected to the at least three channels. Several separating modules and several line modules can be combined to adapt the ventilation system as needed.

Apparatuses, systems and methods are disclosed for separating oil from a blow-by gas of an engine. An example includes a method that includes passing the blow-by gas to a first oil separating apparatus and a second oil separating apparatus, wherein the first oil separating apparatus and the second oil separating apparatus are physically coupled together along interfacing surfaces and in fluid communication with one another as an array, separating the blow-by gas by passing the blow-by gas through respective filters of the first oil separating apparatus and the second oil separating apparatus, removing the oil from the blow-by gas with the respective filters and recombining the blow-by gas after passing from the respective filters; passing the blow-by gas as a single flow stream from the first oil separating apparatus and the second oil separating apparatus.

A first passage communicating a portion downstream side of the compressor in the intake passage and an upstream side of the intercooler with the crankcase, a second passage communicating a portion downstream of the intercooler in the intake passage with the crankcase, and a third passage communicating a portion upstream of the compressor in the intake passage with the crankcase are installed in the turbocharged engine, and a switching valve for switching between a state in which the first passage communicates and the second passage is blocked, and a state in which the first passage is blocked and the second passage communicates is provided.