Complex sentence: In spite of sophisticated technology, it may happen that higher emission values are reached due to inhomogeneous fuel (waste composition), especially in the phases of start up, shut down and malfunction of a plant.
Split into simpler sentences: In spite of sophisticated technology, it may occur that higher emission values can be reached due to the inhomogeneous fuel (waste composition). Especially in the phases of start up, shut down and malfunction of a plant.