Liquid production wastes and process off gases are used for site internal steam generation at DSM/Sisseln. New components and systems were erected and integrated into the existing energy infrastructure in order to ensure waste disposal. STEAG Energy Services was representing the Owner’s Engineer in this projects and had performed the following services: concept preparation, integration planning, tender preparation, proposal evaluation, control of design layout and engineering, construction supervision, commissioning supervision, optimization. In addition to the mentioned services STEAG Energy Services is performing the integration of two process off gases into the firing systems of the boilers K7 and K8 including the realization of necessary modernization work. The SES services were executed in different time periods.