Industrial & Engineering Chemistry Research, Vol.42, No.22, 5457-5461, 2003
Development of nitrolysis for excess sludge treatment II: A factorial study for industrial wastes
Excess sludge generated in industrial wastewater treatment was converted to soluble organic products and gases in a nitrolysis reaction. The conversion of industrial excess sludge reached 80% by mass (99% conversion after removal inerts from the calculation). The most instrumental operating parameters in increasing this conversion were reaction temperature and acid/sludge ratio in the reactor. The reduction in mass and volume of the excess sludge shows promise in reducing the liability and cost associated with disposal. The production of organic acids (e.g., acetic acid) was also demonstrated, leading to an even more promising treatment alternative for excess sludge. The operating parameters that affect the production of organic acids were also studied. The reaction rate of the process was compared to a previously developed model, showing good agreement. The stoichiometry of the process was investigated, showing more than 90 mg of acetic acid and more than 50 mg of formic acid produced per gram of industrial excess sludge reacted.