For wastewater treatment plants pursuing carbon neutrality, diffuse methane emissions from sludge handling processes represent an increasingly important challenge. While anaerobic digestion improves renewable energy recovery, dissolved methane remaining in digested sludge can subsequently be released during storage, dewatering and final disposal, contributing significantly to greenhouse gas (GHG) and NMVOC emissions. This paper presents over 10 years of operational experience with ELOVAC® vacuum degassing at the wastewater treatment plant in Lingen, Germany. Lingen WWTP treated municipal wastewater from 100.000 PE in Germany. ELOVAC was installed as part of a wider sludge treatment optimisation programme, the system was designed to remove dissolved methane and carbon dioxide from digested sludge prior to downstream dewatering and phosphorus recovery. The recovered gas is returned to the plants gas system for beneficial energy use, while simultaneously reducing fugitive emissions by about 150 ton CO2-eq/a. A second key operational benefit is the reduction of phosphate levels, ensuring reliable dewatering performance and preventing operational disruptions caused by struvite formation. By this treatment cake dry solids can be improved by 3-5%DS points, which leads to reduced disposal costs. Operational data from the full-scale installation demonstrate reliable long-term performance under varying sludge and loading conditions. The paper discusses measured and calculated impacts on methane mitigation, process stability, odour reduction and overall plant carbon footprint. Experience from integration with thermal hydrolysis, anaerobic digestion and phosphorus recovery processes will also be presented. The findings highlight the importance of dissolved methane management as utilities move beyond energy efficiency towards comprehensive GHG reduction strategies and net-zero wastewater treatment operations.