The invention is to a process for removing contaminants from a compressor and/or compressor intercooler in a methanol to olefin separation system. The process comprises compressing an effluent in a compressor having an inlet and an outlet and a compressor surface, the compressing occurring under conditions effective to form a contaminant on the compressor surface. A contaminant-removal medium is injected into the compressor or intercooler and the contaminant-removal medium contacts the contaminant under conditions effective to remove the contaminant from the compressor or intercooler inner surface thereby forming a mobile contaminant. The mobile contaminant is then removed from the compressor or intercooler.