title: Comprehensive utilization of the pyrolysis products from sewage sludge.
abstract: Bio-oils were produced from pyrolysis of sewage sludge in a horizontal tubular furnace under the anoxic or anaerobic conditions, by varying operating parameters and moisture content (MC) of the feedstock. Physicochemical properties of the obtained bio-oil (such as density, acid value, kinematical viscosity, high heating value and flash point) were analysed and compared with Chinese fuel standards. Tend, RT and β were found critical to control the yield and physico-chemical properties of bio-oil products. The relative importance of various parameters such as Tend, RT, β and MC was determined and the optimum values for the lowest kinematic viscosity and acid value and the highest yield of the bio-oil were achieved using the orthogonal matrix method. The parameters 550°C, 45 min, 5°C min(-1) and MC of 10% were found effective in producing the bio-oils with most of the desirable physico-chemical properties and yield. Benefit analysis was conducted to further optimize the operating parameters, considering pyrolysis treatment, comprehensive utilization of the pyrolysis products and final disposal of sewage sludge; the results showed the best economy of the pyrolysis parameters 450°C, 75 min, 3°C min(-1) and MC of 10%. The char obtained under this condition may serve as a microporous liquid adsorbent, while the bio-oil may serve as a low grade fuel oil after upgrading it with conventional fuel oil and deacidification. Pyrolysis products may become economically competitive in addition to being environment friendly.
authors.affiliation: a State Key Laboratory of Pollution Control and Resource Reuse , Tongji University , Shanghai 200092 , People's Republic of China.
authors.forename: W Y
authors.initials: WY
authors.lastname: Xu
authors.forename: D
authors.initials: D
authors.lastname: Wu
mesh_terms: D056804:Biofuels / Q000032:analysis*; D006361:Heating / Q000379:methods; D017745:Incineration / Q000379:methods*; D059027:Recycling / Q000379:methods*; D012722:Sewage / Q000032:analysis* / Q000737:chemistry*; D013696:Temperature; D018508:Water Purification / Q000379:methods*
chemical_list: D056804:Biofuels; D012722:Sewage
keywords: benefit analysis; comprehensive utilization; pyrolysis products; sewage sludge; upgrading