| The raw hemp needs to be degummed before it is used in subsequent spinning and other processes,and the biological degumming method is highly favored by enterprises due to its green and pollution-free characteristics.The anaerobic continuous flow biological degumming system solves the problems of expensive bacterial strain preparation,separation of degumming process and bacterial strain preparation,and inability to continuously produce.It realizes the continuous production of "gelatinous bacteria,bacterial enzyme production,and enzymatic degumming",and has a very broad application prospect.However,the existing anaerobic continuous flow biological degumming system has problems such as long degumming time and unstable device operation,which affect the industrial application of continuous flow biological degumming.The research team in the previous research found that both alkaline additives and boiling pretreatment can help improve the continuous flow degumming efficiency.In order to further improve the time efficiency of anaerobic continuous flow degumming and promote the development of industrialization,the experiment first chose boiling pre-treatment as the research topic.By adjusting the types and additives used for pre-treatment,pre-treatment time,and degumming time,the degumming time was shortened from 72 hours to 48 hours.The differences in weight loss rate and chemical composition were analyzed to compare the degumming efficiency,and the fiber physical properties were tested to evaluate the degumming quality,and the water quality indicators were used to estimate the system running stage,and scanning electron microscopy was used to conduct the comprehensive analysis.Then the effect of boiling pretreatment on the anaerobic continuous flow biological degumming efficiency of hemp was explored,and the optimal pretreatment process parameters for hemp degumming were determined.Secondly,to reach the purpose of low consumption and safety,referring to previous research,the pretreatment of soaking hemp was selected for the same analysis as boiling,to explore whether degumming after soaking hemp pretreatment could decrease the degumming time to 48 hours;Finally,in order to improve the degumming efficiency of the degumming tank and improve the structural defects of the degumming tank,the project redesigned,built,and debugged the existing degumming tank,and analyzed the degumming performance of the new degumming system using the new degumming tank.The experiments were designed with single factor variables,and the following conclusions were obtained:(1)Boiling pretreatment can effectively improve the degumming effect of continuous flow systems.Resultshave shown that using 2% sodium hydroxide and boiling for1.5 hours can reduce the anaerobic continuous flow biological degumming time of hemp from72 hours to 48 hours,and meet the quality requirements of the enterprise for degumming.(2)Using the existing degumming tank,no matter which additives were used in this paper,the degumming time cannot be shortened to 48 hours and cannot meet the requirements of the enterprise for degumming quality.(3)The degumming system in this paper has a good removal effect on water-soluble substances,pectin and ash,while the removal effect of hemicellulose is poor.The physical properties of the degummed hemp fiber are good,meeting the strength requirements of the enterprise for the subsequent treatment of degummed hemp.And the use of sodium hydroxide additives in pre-treatment helps to reduce fiber fineness while maintaining the same strength.Scanning electron microscopy analysis of degummed hemp showed that the removal of colloid between the fibers of the degummed hemp bundle was better,but the removal of colloid inside the fibers was less.(4)The new degumming system reconstructed using a new degumming tank has good stability and sealing during no-load operation.(5)The new degumming system can shorten the degumming time to 48 hours in the condition of soaking hemp for 24 hours.(6)The new degumming system can increase the load of hemp raw hemp from 400 g to 600 g.In summary,the project has determined two optimal process parameters for anaerobic continuous flow biological degumming pretreatment,boiling and hemp soaking,which can meet the application requirements.The improved new degumming tank and its new degumming system has solved the problem of unstable operation of the existing anaerobic continuous flow biological degumming system,and also achieves a shortened degumming time in hemp soaking conditions and significantly increases the load of hemp raw hemp.The findings obtained in the paper benefit to promote industrial application of anaerobic continuous flow biological degumming systems in the cannabis industry. |
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