| This thesis is based on the National Nature Science Foundation Item of China (No.50076037) "The fundamental study of clean fuel derived from solid waste in a rotary kiln reactor' and the National '211' Project "The evaluation and experiment of the thermochemical treatment of waste in a rotary kiln reactor.' The used tyre was pyrolyzed in a self-designed pilot-scale rotary kiln which can pyrolyze used tyres of 10-40kg in 1 hour continuously. The utilization of pyrolytic products and the pyrolysis kinetics and mechanism of tyre and tyre components were analyzed.Firstly, the pilot-scale rotary pyrolysis equipment of used tyre and the operation conditions were introduced and the pyrolytic product yields were analyzed.Then, the physicochemical properties of pyrolytic gas from pyrolysis of used tyre in the pilot-scale rotary kiln were analyzed. The functional groups of pyrolytic gas were analyzed qualitatively and semi-quantitatively by GC-MS. The components of pyrolytic gas were analyzed quantitatively by quantitative GC and flue gas analyzer. The effect of pyrolysis temperature on the components, average molecular weight, calorific value of pyrolytic gas, the formation mechanism of pyrolytic gas and distribution of S in the pyrolytic products were studied. The results show that the pyrolytic gas is a clean fuel and can supply enough energy needed in pyrolysis.Afterward, the physicochemical properties of pyrolytic carbon black from pyrolysis of used tyre in the pilot-scale rotary kiln and the utilization of pyrolytic carbon black as commercial carbon black were studied. The proximate and ultimate analysis of pyrolytic carbon black was compared with commercial carbon black N330 and N660. The porosity properties, micromorphology, surface chemical properties, element concentration, inorganic phases and microstructure of pyrolytic carbon black and commercial carbon black were analyzed by N2 adsorption, SEM, FT-IR, XPS, EDAX, XRD, RDF. The mechanical properties of vulcanized rubber reinforced with pyrolytic carbon black were tested and the feasibility of substituting pyrolytic carbon black for commercial carbon black was discussed. The results show that the substituting pyrolytic carbon black for commercial carbon black of medium qulity such as N660 is feasible and the pyrolytic carbon black can replace absolutely the commercial carbon black of low quality used in rubber products of low quality, such as conveyor belts, carrier rings, footwear, etc.The pyrolytic carbon black was washed in acid-base method for its high ash and S contents. The effects of the type, dosage, concentration, temperature and recycling of acid-base reagents, washing time and pyrolytic carbon black particle diameter on the removal of ash and S were studied. The changes of the element concentration, inorganic phases, porosity properties and microstructure during acid-base washing were analyzed by EDAX, XRD, N2 adsorption, SEM, RDF. The chemical reactions in the acid-base washing were analyzed. The results show that the acid wash is an effective and economical way to upgrade the quality of pyrolytic carbon black.
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