添加剂及氨碱处理对青贮玉米秸秆厌氧消化特性的影响

发布时间：2018-06-20 11:28

本文选题：青贮玉米秸秆 + 厌氧消化　；参考：《兰州理工大学》2017年硕士论文

【摘要】：本文以青贮玉米秸秆为原料,研究了青贮玉米秸秆与牛粪在总固体(Total Solid,TS)比3:7混合、接种量30%、37±1℃条件下厌氧消化产甲烷特性和系统稳定性的变化。尝试应用4.5%氨水(Ammonium Hydroxide,AH)和4%Na OH(Sodium Hydroxide,SH)对青贮玉米秸秆进行联合预处理,并使用Modified Gompertz方程和Logistic函数对试验数据进行拟合和分析,为青贮玉米厌氧消化产业化应用提供一定的参考和依据。本研究得出以下结论:1.青贮玉米秸秆与干黄玉米秸秆厌氧消化特性对比青贮玉米秸秆(ME)在青贮24个月后厌氧消化产气特性与干秸秆(DC)相近,差异在1%以内,挥发性固体(volatile solid,VS)产气率较DC组提高约3.40%,VS产甲烷率提高约2.63%。2.由不同青贮玉米秸秆与牛粪混合厌氧消化试验可得:(1)不同青贮玉米秸秆与牛粪混合厌氧消化在原料特性、产气特性和系统稳定性相近。(2)通过产甲烷潜力(Biochemical Methane Potential,BMP)试验和Modified Gompertz方程、Logistic函数的拟合,FA组最大甲烷累积产量约为204.02~209.86m L·g-1TS,最大产甲烷速率约为10.20~10.22 m L/g·d-1 TS,延滞期约为12~14d,厌氧消化试验综合表现最佳。3.青贮玉米秸秆经氨联合处理后厌氧消化试验结果:(1)各处理组运行稳,化学需氧量(Chemicals Oxygen Demand,COD)消解率远大于未处理组。(2)各处理组间差异明显,且无显著延滞期或延滞期较短。结合通过BMP试验和两个模型可知,两个模型对AH-PA组的拟合效果均不理想(R2分别为0.7148和0.6903),其余处理组的拟合数据表明Logistic函数的拟合更佳,R2最小值出现在AH-FA组(0.9788)。AH-LB组延滞期最大,约为5~6d。(3)氨处理在一定程度上降低了青贮玉米秸秆的厌氧消化产气特性,其中AH-FA组整体降幅最大,累积产气量约降低63.71%;AH-PA组的降幅最小,累积产气(甲烷)量、TS/VS产气率降幅分别为17.24%、22.22%、17.24%和3.05%。4.青贮玉米秸秆经碱联合处理后厌氧消化试验结果:(1)同氨处理组,系统稳定性高。(2)各处理组差异明显,无显著延滞期或延滞期较短。结合通过BMP试验和两个模型可得,两个模型对Na OH处理组的拟合均不理想(SH-LB和SH-ME组除外,两个模型的R2均大于0.99),整体上Logistic函数的拟合效果更优异。(3)Na OH处理对不同青贮原料的产气特性影响不同:SH-CB组各项数据均大于未处理组,其中VS产甲烷率提升最大,较未处理组提升约28.30%;SH-FA、SH-ME和SH-PA组则是部分提高部分下降;SH-LB组的各项指标均低于未处理组,其中TS产甲烷率降幅最大,约为33.40%。5.同等条件下氨联合处理与碱联合处理对青贮玉米秸秆影响的对比:(1)共性:两种处理方式均明显的中和青贮玉米秸秆的p H,并加速原料的水解酸化过程,提升厌氧消化系统对原料的利用率和转化率,缩短厌氧消化试验的周期,厌氧消化系统的稳定性和效率优质很改善。(2)差异:氨处理组除平均甲烷体积分数方面比未处理组提高约0.92~3.08%(AH-CB、AH-FA和AH-LB)外,其它方面均远低于未处理组;Na OH处理组则表现各异,SH-CB组各项数据均大于未处理组,SH-FA、SH-ME和SH-PA组则是部分提高部分下降,SH-LB组的各项指标均低于未处理组。(3)两个模型对AH-PA和SH-PA组的拟合效果均不理想,且整体上看Modified Gompertz方程的拟合效果均不如Logistic函数,且较Na OH处理组更适于氨处理组的拟合。
[Abstract]:In this paper, the silage corn straw was used as the raw material to study the change of methane production and system stability in the anaerobic digestion of silage corn straw and cow dung mixed with total solid (Total Solid, TS) and the inoculation amount 30%, 37 + 1 C. 4.5% ammonia (Ammonium Hydroxide, AH) and 4%Na OH (Sodium Hydroxide, SH) were applied to the silage corn straw. Combined with Modified Gompertz equation and Logistic function, the experimental data were fitted and analyzed in order to provide some reference and basis for the industrial application of anaerobic digestion for silage corn. The following conclusions were drawn: 1. comparison of the anaerobic digestion characteristics of silage corn straw and dry yellow corn straw (ME) in green corn straw After 24 months of storage, the characteristics of anaerobic digestion were similar to that of dry straw (DC), the difference was within 1%. The gas yield of volatile solid (volatile solid, VS) was raised about 3.40% compared with that of DC group. The methane production rate of VS was improved by 2.63%.2. by the mixed anaerobic digestion test of different silage corn stalks and cow dung: (1) mixed anaerobic digestion of different silage corn stalks and cow dung In the properties of raw materials, the gas production characteristics and system stability are similar. (2) with the methane production potential (Biochemical Methane Potential, BMP) test, the Modified Gompertz equation and the Logistic function fitting, the maximum methane accumulation of FA group is about 204.02~209.86m L. G-1TS, the maximum methane production rate is approximately 10.20~10.22. 14d, anaerobic digestion test showed that the best.3. silage corn straw combined anaerobic digestion test results: (1) the treatment group runs steadily, the chemical oxygen demand (Chemicals Oxygen Demand, COD) digestion rate is far greater than the untreated group. (2) the difference between the treatment groups is obvious, and there is no significant delay or delay period. Combined through BMP test And the two models showed that the fitting effect of the two models to the AH-PA group was not ideal (R2 0.7148 and 0.6903 respectively). The fitting data of the rest of the treatment groups showed that the fitting of the Logistic function was better, the minimum R2 value appeared in the AH-FA group (0.9788).AH-LB group, and the 5~6d. (3) ammonia treatment reduced the silage corn straw to a certain extent. In anaerobic digestion, the total reduction of AH-FA group was the largest, the cumulative gas production was reduced by 63.71%, the decrease of AH-PA group was the smallest, the cumulative gas production (Jia Wan), and the decrease of TS/VS production rate were 17.24%, 22.22%, 17.24% and 3.05%.4. silage corn stalk after alkali treatment. (1) the system stability was high in the same ammonia treatment group. (2) the difference of each treatment group is obvious, there is no significant delay or delay. Combining the BMP test and two models, the fitting of the two models to the Na OH treatment group is not ideal (except the SH-LB and SH-ME group, the R2 of the two models are greater than 0.99), and the fitting effect of the Logistic function on the whole is better. (3) Na OH treatment for different silage materials The effects of gas production were different: the data of SH-CB group were greater than those in the untreated group, and the methane production rate of VS was increased by 28.30%, while SH-FA, SH-ME and SH-PA were partly reduced, and the indexes of SH-LB group were lower than those in the untreated group, and the methane production rate of TS was the largest, which was about the same conditions as 33.40%.5. under the same condition. The effects of combined treatment and alkali treatment on silage corn straw were compared: (1) common: two treatment methods were all obviously neutralized with silage corn straw P H, and accelerated the hydrolysis acidification process of raw materials, improved the utilization rate and conversion rate of anaerobic digestion system to raw materials, shortened the cycle of anaerobic digestion test, and the stability of anaerobic digestion system. And the efficiency is better. (2) difference: the ammonia treatment group is far lower than the untreated group in addition to the average methane volume fraction 0.92~3.08% (AH-CB, AH-FA and AH-LB), and the Na OH treatment group is different, the SH-CB group is larger than the untreated group, SH-FA, SH-ME and SH-PA groups are partially improved. All the indexes of the SH-LB group were lower than those in the untreated group. (3) the fitting effect of the two models to the AH-PA and SH-PA groups was not ideal, and the fitting effect of the Modified Gompertz equation on the whole was not as good as the Logistic function, and it was more suitable for the fitting of the ammonia treatment group than the Na OH treatment group.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S816.53

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