A recent development in waste management and engineering has shown that the cellulase can be used for the liquefaction of organic fractions in household waste. The focus of this study was to optimize the enzyme hydrolysis of thermally treated municipal solid waste (MSW) by the addition of surfactant. Concurrently, the enzyme performance was analysed on pure cellulose in a solution of MSW wastewater. Results showed no effect of surfactant addition to the hydrolysis media as measured by viscosity and particle size distribution. MSW treatment wastewater was found to contain a high amount of calcium, potassium, sodium, chloride and others that may affect cellulolytic enzymes. Cellulase performance showed no effect of adding the metal ion-chelating agent EDTA to the solution. The cellulases were stable, tolerated and functioned in the presence of several contaminants.