CAJ | 학술논문

为提高纤维素类原料厌氧消化性能,降低处理成本,该研究采用复合菌剂和2%、4%、6%、8%NaOH(以玉米秸秆干物质质量计)对以玉米秸秆为代表的纤维素类发酵原料进行预处理,研究不同预处理方式对纤维素等成分的含量、厌氧消化性能和生产成本的影响.试验结果表明,经复合菌剂和NaOH处理后,秸秆的木质素、纤维素和半纤维素总含量显著降低,产气量和产气效率提高,其中,添加6%NaOH的预处理方式效果最佳,复合菌剂次之,与未处理相比,单位干物质质量产气量从120.70 mL/g分别提高到374.30和334.76 mL/g,厌氧消化时间从大于30 d缩短到18和19 d.采用复合菌剂和2%、4%、6%、8%NaOH预处理生产沼气所需的可变成本分别为0.72、0.80、0.98、1.09和1.57元/m3.综合考虑产气效率和生产成本,复合菌剂预处理由于具有较低的处理成本、较高的产气效率和较短的消化时间更利于推广应用.
위제고섬유소류원료염양소화성능,강저처리성본,해연구채용복합균제화2%、4%、6%、8%NaOH(이옥미갈간간물질질량계)대이옥미갈간위대표적섬유소류발효원료진행예처리,연구불동예처리방식대섬유소등성분적함량、염양소화성능화생산성본적영향.시험결과표명,경복합균제화NaOH처리후,갈간적목질소、섬유소화반섬유소총함량현저강저,산기량화산기효솔제고,기중,첨가6%NaOH적예처리방식효과최가,복합균제차지,여미처리상비,단위간물질질양산기량종120.70 mL/g분별제고도374.30화334.76 mL/g,염양소화시간종대우30 d축단도18화19 d.채용복합균제화2%、4%、6%、8%NaOH예처리생산소기소수적가변성본분별위0.72、0.80、0.98、1.09화1.57원/m3.종합고필산기효솔화생산성본,복합균제예처이유우구유교저적처리성본、교고적산기효솔화교단적소화시간경리우추엄응용.
@@@@Due to the existence of lignin in crop straws, the anaerobic digestion by only crop straw would be demonstrated as low in conversion and utilization efficiency. Lots of studies reported that the pretreatment of crop straws would destroy the combination of cellulose, hemicelluloses and lignin, and enhance the anaerobic performance. To improve anaerobic performance, in this study, corn straws were pretreated by composite microbes and NaOH to investigate their effects on straw components, anaerobic digestion performance and production costs. Corn straws were pretreated by the addition of composite microbes and NaOH with 2%、4%、6%、8%(calculated by dry weight of corn straws), and retting for 3 days with a thermostat setting of (38±2℃). Then the samples of the treated and untreated corn straws were withdrawn to determined cellulose, hemicelluloses and lignose contents in dry matter. Then corn straws were inoculated with sludge (40%of sludge and 60%of treated corn straw in dry matter). Anaerobic digestion experiments were carried out in 30 days under temperature of 38±2℃, and the daily biogas yields were measured by the gas-collecting method of drainage water. A control with untreated corn straws was also done to compare the difference with treated ones. The experiments were set up in triplicate. The experiment results showed that corn straws’total contents of cellulose, hemicelluloses and lignose were decreased. Compared with the control, the pretreatment method by 8%NaOH, 2%NaOH and 8%NaOH demonstrated better degradation effects for cellulose, hemicelluloses and lignose, and the maximum degradation rate were 33.5%, 38.7% and 23.1%, respectively. The reduction of cellulose, hemicelluloses and lignose helped to improve the anaerobic digestion efficiencies. The anaerobic experiments revealed that the biogas yields and production efficiencies of corn straws after pretreatment were improved. Compared with the control, their biogas production for unit dry weight were elevated from 120.70 mL/g·TS to 334.76, 309.51, 333.57, 374.30 and 309.71 mL/g·TS, respectively. The NaOH pretreatment with 6% addition were demonstrated as giving the best result. The digestion times that were reached to 80%of the maximum gas production were 21, 24, 19, 18 and 26 d for pretreatment by composite microbes and NaOH with 2%、4%、6%、8%. However, the amount of biogas produced by the control in 30 days was only 32.25%of the maximum gas production. These results showed that the pretreatments increased the gas production rates. The pretreatment variational costs were calculated to analyze whether the methods were fit for popularization. The variational costs included the fees for both raw materials and pretreatment reagents. In this study, the prices of composite microbes, NaOH and corn straw were calculated as 4 yuan/kg, 25 yuan/kg and 150 yuan/t, respectively. The variational costs for addition of composite microbes and NaOH with 2%、4%、6%、8% are 0.72, 0.80, 0.98, 1.09 and 1.57 yuan/m3, respectively. Taking anaerobic digestion performances and pretreatment costs into consideration, the pretreatment method with composite microbe would be a more conducive way to popularize.