Research On The Pyrolysis Of Edible Fungus Residue

With the continuous development of edible fungus industry,the problem of the edib le fungus residue is becoming increasingly prominent.Widespread attention at home and abroad has been paid to how to effectively make use of edible fungus residue in rece nt years.At present,the use of the edible fungus residue mainly focused on fuel,fertilizer,feed additives and so on.The research of transform edible fungus residue into biogas0 b io-oil and bio-char by thermo-chemical conversion technology was very little.In this pap er,the use of edible fungus residue pyrolysis to produce gas,in order to develop the edi ble fungus residue resources,open a new method for the utilization of the edible fungus residue,making the edible fungus production to achieve "resources-production-consumpti on-renewable resources" the cycle of industrial models.In this thesis,the kinetics of edibl e fungus pyrolysis were studied,and then on this basis,pyrolysis conditions of edible fun gus residue were systemically studied in a fixed-bed reactor.The effect of temperature,pa rticle size,catalyst on the pyrolysis of edible fungus residue were determined,and the py rolysis products(gas0liquid and solid) were analyzed.At the same time,the effect of py rolysis temperature and time on the composition and content of the pyrolysis products of edible fungus residue were studyed by Py GC/MS,and the pyrolysis liquid product was analyzed through the GC-MS online system.The main contents and results were as follows:(1) the pyrolysis reaction kinetics of edible fungus residue were conducted by thermogravimetric analyzereand the results showed that with the improvement of heating rate,the rate of pyrolysis reaction significantly paces up,the maximum pyrolysis rate increases,and the corresponding temperature is shifted to the high temperature region,when the heating rate is 10,20 and 30 E/min,the temperature of the maximum mass loss rate is 333.0 E,344.5 E and 344.5 E respectively,the corresponding maximum weight loss rate is 64.19 %,65.82 % and 62.24 % respectively.With the increasing of particle size,the pyrolysis temperature at the maximum mass loss rate continues to increase.When the particle size is 0.15~0.30 mm,0.30~0.80 and 0.8~1.25 mm,the temperature of the maximum mass loss rate is 344.5 E,349.1 E and 349.1 E respectively.And adding catalyst into the reaction can greatly decrease the reaction activation energy,the activation energy of adding 10 wt.% K2CO3 catalyst compared to 10 wt.% CaO reduced the magnitude of the larger,shows that the K2CO3 catalyst compared with CaO catalyst is more advantageous to the pyrolysis of edible fungus residue.(2) The effects of temperature,particle size,residence time on the products of edible fungus residue were researched in the fixed-bed reactor.The results show that high temperature,small particle size of raw materials and long residence time helps to improve gas production.With the increase of temperature,the content of CO decreased, the content of CO2 increased,and the content of H2 firstly increased and then decreased,while the content of CH4 decreased,other gases due to the low content,change is not obvious.We found that increasing the temperature can reduce the species of tar fell significantly by GC-MS analysis,and the proportion of the total number of without much branched chain benzene ring structure materials such as benzene,naphthalene,acenaphthene and phenanthrene,pyrene and fluoranthene increased significantly.(3) The influence of different types of catalysts such as CaO,K2CO3,ZnCl2 on the pyrolysis products of edible fungus residue in the fixed-bed reactor.With the addition of catalysts,pyrolysis gas composition changed larger,H2 had improved significantly and CO2 decreased obviously.Above all,CaO could improve the content of H2 best,adding CaO catalyst,the content of H2 was increased of 64.72 % compared with sample without catalyst;K2CO3 for reducing CO2 in the best effect,the content of CO2 was reduced of 18.28% compared with sample without catalyst,while found that ZnCl2 is very effective to improve the content of CH4 and C2H4,and improved 9.67 % and 40.54 %,respectively.The addition of catalyst can make the tar composition more simple and content lower.When the residence time is 23.015 min,high added value product such as 2,6-Di-tert-butyl-4-methylphenol content reached 30~60 %.(4) Experiments were carried out to study the pyrolysis of edible fungus residue by Py GC/MS method.The study found that when the pyrolysis time is 10 s,the pyrolysis temperature is lower than 500 E,with the increase of pyrolysis temperature,the types and yield of pyrolysis products increased.When the temperature is higher than 500 E,the types of pyrolytic products remained stable,only the yield of products changed;when the pyrolysis temperature was 600 E,high value added product yield was the largest,the content of phenol was 4.42 %,2,3-dihydrobenzofuran was 11.67 %,4-vinyl-2-methoxyphenol was 8.59 %,2,6-dimethoxyphenol was 4.70 % and N-phenyl-2-naphthylamine was 6.37 %;when the pyrolysis temperature was 400 E,the types of pyrolysis products was relatively few,easy to separation and purification of high value-added products.