CN118256566A - Combined production method for producing hydrogen by photosynthetic organisms and producing ethanol by organisms from crop straws - Google Patents
Combined production method for producing hydrogen by photosynthetic organisms and producing ethanol by organisms from crop straws Download PDFInfo
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Classifications
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E50/00—Technologies for the production of fuel of non-fossil origin
- Y02E50/10—Biofuels, e.g. bio-diesel
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- Preparation Of Compounds By Using Micro-Organisms (AREA)
Abstract
The invention provides a combined production method for producing hydrogen and ethanol by photosynthetic organisms of crop straws, belonging to the technical field of biology. A combined production method for producing hydrogen and ethanol by photosynthetic organisms of crop straws takes a hydrogen production culture medium containing crop straw powder as a fermentation culture medium, and is inoculated with cellulase, photosynthetic hydrogen production bacteria HAU-M1 and active dry yeast for brewing to ferment; the concentration of the crop straw powder is 5-55 g/L. According to the invention, crop straws are used as biomass raw materials, active dry yeast for brewing wine is added at different stages of hydrogen production to carry out ethanol fermentation, and the energy conversion of biomass is realized by utilizing a one-step method and a two-step method for hydrogen-alcohol co-production, so that the yield of hydrogen and ethanol is improved, and meanwhile, the sustainable development of energy, environment and economy is also improved.
Description
Technical Field
The invention belongs to the technical field of biology, and particularly relates to a combined production method for producing hydrogen and ethanol by photosynthetic organisms of crop straws.
Background
China is used as a large agricultural country, a large amount of agricultural wastes are produced annually, the traditional straw treatment mode is firstly and directly used for burning, a series of outstanding problems such as resource waste and environmental pollution exist, and in order to solve the problems, the biological straw is utilized in modes [1] such as biomass anaerobic fermentation, biomass liquid fuel, biomass power generation and biomass solid molding fuel by energy. Biological hydrogen energy and bioethanol are widely regarded as promising green sustainable alternative novel energy sources, biomass such as straw and the like is utilized as raw materials for photo-biological fermentation, so that treatment of a large amount of straw waste can be completed, pollutant emission caused by straw combustion can be reduced, utilization of solar energy is increased, and efficient output and utilization [2] of clean energy are realized.
The photo-fermentation hydrogen production is widely considered as an ideal hydrogen production mode at present, the sources of raw materials are wide, and the photo-fermentation hydrogen production comprises organic wastes [3,4] such as carbohydrates and proteins in plants, and the like, can effectively convert the energy of the raw materials into hydrogen, and has the advantages of treating the organic wastes and utilizing solar energy to produce clean energy. Researchers can automatically adjust and control the reaction environment of photosynthetic bacteria, optimize the hydrogen production process and increase the energy conversion efficiency [5,6] in the hydrogen production process. Ivanenko et al [7] summarize the basic principles of photo-biological hydrogen production and aim to move from laboratory studies to various improved bio-hydrogen production strategies for full-scale applications. Zhang et al [8] selected various energy grasses as experimental materials in the study, performed hydrogen production experiments under different enzymolysis times, and studied the method for producing bio-hydrogen by photo-fermentation with energy grasses as substrates by changing the enzymolysis time. The influence of active saccharification and passive saccharification and fermentation on biological hydrogen production by alfalfa photo-fermentation was studied by using HAU-M1 as a photo-fermentation hydrogen-producing bacterium by Lu et al [9]. The biomass hydrogen production technology has been developed and matured, the biological hydrogen production process obtains larger conversion efficiency, but the tail liquid after the fermentation hydrogen production still contains available nutrient substances, and the energy conversion efficiency of the substrate is still to be improved.
The technology for preparing ethanol by biomass has long been developed, and a set of mature technological production flow exists. The traditional ethanol industry mainly depends on edible crops such as corn, sugarcane and the like as raw materials, which not only causes excessive consumption of edible crop resources, but also causes potential threat [10,11] to grain safety. The biomass ethanol can be prepared by using waste, crop straws, forest waste and other non-edible biomass as raw materials, so that the problems in the traditional ethanol production are effectively solved. Kumar [12] was fermented using reducing sugars from coconut husk and rice bran as substrates, and produced 0.53% ethanol by the action of baker's yeast and wine starter, respectively. Significant advances have been made in the research and development of biomass ethanol production technology, but some challenges remain. The greatest difficulty is how to increase biomass conversion efficiency and reduce production costs.
The research on ethanol production by biomass and biological hydrogen production is continuous and intensive, and mature production technology and fuel production are provided, so that the research possibility is provided for biomass photo-fermentation coupling co-production of ethanol. At present, li et al [13] developed an effective acetone-butanol-ethanol (ABE) fermentation process that utilizes the thermo-catalytic technology to manipulate the microbial metabolism of Clostridium to enhance the co-production of butanol and hydrogen. Angel Mario et al [14] used genetically engineered E.coli to co-produce hydrogen and ethanol by dark fermentation, analyzed the impact on environmental and economic sustainability of lignocellulosic biorefineries, and concluded that co-production schemes could be substituted for lignocellulosic ethanol biorefineries. Khamanitjaree Saripan et al [15] utilize one-step fermentation of sugarcane to increase hydrogen and ethanol production potential and enhance the utilization of cellulose in sugarcane. However, the current biomass hydrogen and ethanol production has the problem of low yield. Therefore, development of efficient co-production technology for producing hydrogen and producing ethanol from agricultural wastes is urgently needed.
Reference to the literature
[1]Zhang CY,Chen WH,Hof SH,et al.Pelletization property analysis of raw and torrefied corn stalks for industrial application to achieve agricultural waste conversion[J].Energy,2023,285.
[2]Khan A,Niazi MBK,Ansar R,et al.Thermochemical conversion of agricultural waste to hydrogen,methane,and biofuels:A review[J].Fuel,2023,351.
[3]Sadh PK,Chawla P,Kumar S,et al.Recovery of agricultural waste biomass:A path for circular bioeconomy[J].Science of the Total Environment,2023,870.
[4]Lu C,Zhang Z,Ge X,et al.Bio-hydrogen production from apple waste by photosynthetic bacteria HAU-M1[J].International Journal of Hydrogen Energy,2016,41(31):13399-13407.
[5]Wang Y,Zhou X,Hu J,et al.A comparison between simultaneoussaccharification and separate hydrolysis for photofermentative hydrogenproduction with mixed consortium ofphotosynthetic bacteria using corn stover[J].International Journal ofHydrogen Energy,2017,42(52):30613-30620.
[6]Lu C,Zhang H,Zhang Q,et al.An automated control system forpilot-scale biohydrogen production:Design,operation and validation[J].International Journal ofHydrogen Energy,2020,45(6):3795-3806.
[7]Ivanenko AA,Laikova AA,Zhuravleva EA,et al.Biological productionof hydrogen:From basic principles to the latest advances in processimprovement[J].International Journal ofHydrogen Energy,2024,55:740-755.
[8]Zhang Y,Zhang H,Lee DJ,et al.Effect of enzymolysis time onbiohydrogen production from photo-fermentation by using various energy grassesas substrates[J].Bioresource Technology,2020,305.
[9]Lu CY,Jing YY,Zhang H,et al.Biohydrogen production through activesaccharification and photo-fermentation from alfalfa[J].Bioresource Technology,2020,304.
[10]Lu CY,Wang GT,Zhang QG,et al.Comparison of biorefinerycharacteristics:Photo-fermentation biohydrogen,dark fermentation biohydrogen,biomethane,and bioethanol production[J].Applied Energy,2023,347.
[11]Wang G,Lu C,Liang X,et al.Strategiesfor the Biotransformation ofTung Leaves in Bioethanol Fermentation.Fermentation,2023.9,DOI:10.3390/fermentation9110986.
[12]Narendra Kumar HK,Chandra Mohana N,Rakshith D,et al.Bioprocessing of cellulosic waste biomass for ethanol production byChryseobacterium culicis Bp16[J].Sustainable Chemistry and Pharmacy,2023,33:101081.
[13]Li JZ,Zhang YF,Sun K,et al.Optimization of a cathodicelectro-fermentation process for enhancing co-production of butanol andhydrogen via acetone-butanol-ethanol fermentation of[J].Energy Conversion andManagement,2022,251.
[14]Lopez-Hidalgo AM,G,Rodriguez F,et al.Co-production of ethanol-hydrogenby genetically engineered
in sustainable biorefineries for lignocellulosic ethanol production[J].Chemical Engineering Journal,2021,406.
[15]Saripan K,Reungsang A,and Sittijunda S.Co-production ofhydrogen and ethanol by Thermoanaerobacterium thermosaccharolyticum KKU-ED1 from alpha-cellulose and cellulose fraction of sugarcane bagasse[J].Bioresource Technology Reports,2021,15:100759.
Disclosure of Invention
In view of the above, the invention aims to provide a combined production method for producing hydrogen and ethanol by photosynthetic organisms from crop straws, which uses crop straws as biomass raw materials, and adds yeast at different stages of hydrogen production to ferment ethanol, thereby improving the yield of hydrogen and ethanol.
The invention provides a combined production method for producing hydrogen and ethanol by photosynthetic organisms of crop straws, which comprises the following steps:
taking a hydrogen production culture medium containing crop straw powder as a fermentation culture medium, and inoculating cellulase, photosynthetic hydrogen production bacteria HAU-M1 and active dry yeast for brewing to ferment;
The concentration of the crop straw powder is 5-55 g/L.
Preferably, the photosynthetic hydrogen-producing bacteria HAU-M1 and the brewing active dry yeast are simultaneously inoculated into the fermentation medium.
Preferably, the fermentation time is 12-84 hours;
the initial pH value of the fermentation is 6.8-7.2;
the fermentation temperature is 28-32 ℃;
The illumination intensity of the fermentation is preferably 2950-3050 Lux.
Preferably, the photosynthetic hydrogen-producing bacteria HAU-M1 are firstly inoculated into a fermentation medium for hydrogen-producing fermentation, and then are inoculated with active dry yeast for brewing wine for ethanol fermentation after the hydrogen-producing fermentation is finished.
Preferably, the hydrogen production fermentation time is 12-84 hours;
The initial pH value of the hydrogen-producing fermentation is 6.8-7.2;
the temperature of the hydrogen production fermentation is 28-32 ℃;
The illumination intensity of the hydrogen-producing fermentation is 2950-3050 Lux.
Preferably, the ethanol fermentation time is 3-36 hours;
the temperature of the ethanol fermentation is 34-36 ℃;
and fermenting the ethanol in a dark place.
Preferably, the inoculation amount of the photosynthetic hydrogen-producing bacteria HAU-M1 is 20% -30%;
the inoculation amount of the active dry yeast for brewing wine is 0.95-1.05 g/L.
Preferably, the concentration of the crop straw powder is 15-45 g/L.
Preferably, the crop species include at least one of the following: corn stalks, wheat stalks, rice stalks and peanut vines.
Preferably, the addition amount of the cellulase is 0.39-0.41 mL/g straw.
The invention provides a combined production method for producing hydrogen and ethanol by photosynthetic organisms of crop straws, which comprises the following steps: taking a hydrogen production culture medium containing crop straw powder as a fermentation culture medium, and inoculating cellulase, photosynthetic hydrogen production bacteria HAU-M1 and active dry yeast for brewing to ferment; the concentration of the crop straw powder is 5-55 g/L. According to the invention, crop straws are used as biomass raw materials, photosynthetic hydrogen-producing bacteria HAU-M1 are utilized for hydrogen-producing fermentation, yeast is added at different stages of hydrogen production for ethanol fermentation, the concentration of the raw materials is limited, and the energy conversion of biomass is realized by utilizing a one-step method and a two-step method for hydrogen-alcohol co-production, and simultaneously, a large amount of hydrogen and ethanol content is obtained. The method of the invention can realize the co-production research of hydrogen and ethanol while realizing the fermentation of biomass photosynthetic organisms to produce hydrogen and ethanol, and realize the full utilization of agricultural straws and the sustainable development of energy, environment and economy.
The combined production method provided by the invention specifically limits the inoculation time of photosynthetic hydrogen-producing bacteria HAU-M1 and active dry yeast for brewing wine, and forms a one-step method hydrogen alcohol co-production method and a two-step method hydrogen alcohol co-production method respectively. Experimental results show that the hydrogen production effect is best when the concentration of the corn straw in the two-step hydrogen alcohol co-production is 25g/L, the accumulated hydrogen production is 350.08mL, the hydrogen production per unit straw is 70.02mL/g, the ethanol concentration after yeast addition and the maximum ethanol production per unit corn straw are 1.181g/L and 0.1345g/L respectively, and the concentration is improved by 13.89% compared with that before yeast addition. The concentration of the ethanol produced by the hydrogen alcohol produced by the one-step method and the accumulated hydrogen produced by the hydrogen alcohol produced by the one-step method are 6.40g/L and 153.70mL respectively, and the maximum energy conversion efficiency is 25.96% when the concentration of the corn straw is 5 g/L. Compared with a one-step method, the method has the advantages that the highest accumulated hydrogen yield of the two-step method is 2.45 times of the highest accumulated hydrogen yield of the one-step method, and more ethanol is converted by the one-step method.
Drawings
FIG. 1 is a graph showing the effect of different substrate concentrations on the co-production of hydrogen and alcohol in a one-step process, including hydrogen gas volume fraction (a), cumulative hydrogen production (b), redox potential (c), pH (d), reducing sugar concentration (e) and ethanol concentration (f);
FIG. 2 is a graph showing the effect of different substrate concentrations on the co-production of hydrogen and alcohol in a two-step process, including hydrogen content (a), cumulative hydrogen production (b), redox potential (c), pH (d), reducing sugar concentration (e) and ethanol concentration (f);
FIG. 3 shows the light conversion efficiency, wherein (a) is the light conversion efficiency of the one-step process; (b) the light conversion efficiency of the two-step method;
FIG. 4 shows energy conversion efficiency, wherein (a) is energy conversion efficiency of a one-step process; (b) is the energy conversion efficiency of the two-step process.
Detailed Description
The invention provides a combined production method for producing hydrogen and ethanol by photosynthetic organisms of crop straws, which comprises the following steps:
Taking a hydrogen production culture medium containing crop straw powder as a fermentation culture medium, and inoculating cellulase, photosynthetic hydrogen production bacteria HAU-M1 and active dry yeast for brewing to ferment; the concentration of the crop straw powder is 5-55 g/L.
In the present invention, the co-production process preferably includes a one-step fermentation process or a two-step fermentation process. The one-step fermentation method preferably means that the photosynthetic hydrogen-producing bacteria HAU-M1 and the active dry yeast for brewing wine are simultaneously inoculated into a fermentation medium for fermentation. The hydrogen-producing medium is preferably an aqueous solution comprising the following components in the following amounts: mgCl 20.2 g/L、NH4 Cl 0.4g/L, naCl g/L, sodium glutamate 3.56g/L, yeast extract 0.1g/L and K 2HPO4 0.5 g/L. The concentration of the crop straw powder is preferably 15-45 g/L, more preferably 25-35 g/L. The crop species include at least one of the following: corn stalks, wheat stalks, rice stalks and peanut vines. The grain size of the crop straw powder is preferably 60-80 meshes, more preferably 70 meshes. The addition amount of the cellulase is preferably 0.39-0.41 mL/g straw, more preferably 0.4mL/g straw. The inoculation amount of the photosynthetic hydrogen producing bacteria HAU-M1 is preferably 20% -30%, more preferably 25%. The inoculation amount of the active dry yeast for brewing wine is preferably 0.95-1.05 g/L, more preferably 1g/L. The fermentation time is preferably 12 to 84 hours, more preferably 24 to 60 hours, and still more preferably 36 to 48 hours. The initial pH of the fermentation is preferably from 6.8 to 7.2, more preferably 7.0. The method for adjusting the pH value of the fermentation medium is not particularly limited, and agents which are well known in the art for adjusting the pH value can be used, for example, a citric acid/sodium citrate buffer solution with pH=4.8 is used for adjusting the pH value of the system, so that the pH value of the fermentation medium tends to be stable. The temperature of the fermentation is preferably 28 to 32 ℃, more preferably 30 ℃. The illumination intensity of the fermentation is preferably 2950 to 3050Lux, more preferably 3000Lux.
In the embodiment of the invention, corn straw is used as a raw material to explain the effect of jointly producing hydrogen and ethanol by using crop straw as biomass. Experiments show that the volume fraction of hydrogen is increased greatly within 12-24 h of fermentation, the accumulated hydrogen yield is increased continuously within 60h, and the higher the concentration of crop straw powder is, the higher the hydrogen yield is. The maximum unit straw hydrogen production observed when the concentration of crop straw powder is 25g/L is 28.60mL/g. In the aspect of ethanol production, the concentration of crop straws is increased, the concentration of the ethanol shows a remarkable increasing trend, the maximum concentration of the ethanol obtained by a 55g/L experimental group is 7.09g/L, and the maximum ethanol yield per unit straw is 0.74g/L. The concentration of the ethanol produced by the hydrogen alcohol produced by the one-step method and the accumulated hydrogen produced by the hydrogen alcohol produced by the one-step method are 6.40g/L and 153.70mL respectively, and the maximum energy conversion efficiency is 25.96% when the concentration of the corn straw is 5 g/L.
In the two-step fermentation method, the photosynthetic hydrogen-producing bacteria HAU-M1 are preferably inoculated into a fermentation medium for hydrogen production fermentation, and then the fermentation medium is inoculated with active dry yeast for brewing wine for ethanol fermentation after the hydrogen production fermentation is finished. The variety of the fermentation medium, the concentration of crop straw and the addition amount of cellulase are fermented by the same step method, and no detailed description is given here. The hydrogen-producing fermentation time is preferably 12 to 84 hours, more preferably 24 to 60 hours, and still more preferably 36 to 45 hours. The initial pH of the hydrogen-producing fermentation is preferably from 6.8 to 7.2, preferably 7.0. The temperature of the hydrogen-producing fermentation is preferably 28 to 32 ℃, more preferably 30 ℃. The illumination intensity of the hydrogen-producing fermentation is preferably 2950-3050 Lux, more preferably 3000Lux. In the embodiment of the invention, the hydrogen production fermentation is carried out by adopting different crop straw concentrations, and the result shows that the maximum hydrogen content is 43.83% when the crop straw concentration is 25g/L for fermentation. The gas production was stopped at 84 hours after the hydrogen production fermentation was performed, and the hydrogen production rate was decreased after 60 hours after the fermentation was performed. For the accumulated hydrogen production, the accumulated hydrogen production of the fermentation medium with the crop concentration of 25g/L is optimal, the accumulated hydrogen production is 350.08mL at the highest, and meanwhile, the accumulated hydrogen production of the fermentation medium with the crop concentration of 25g/L is 70.02mL/g.
In the present invention, the time for the ethanol fermentation is preferably 3 to 36 hours, more preferably 6 to 12 hours. The temperature of the ethanol fermentation is preferably 34 to 36 ℃, more preferably 35 ℃. The ethanol fermentation is preferably performed in a dark place. The inoculation amount of the photosynthetic hydrogen producing bacteria HAU-M1 is preferably 20% -30%, more preferably 25%. The inoculation amount of the active dry yeast for brewing wine is preferably 0.95-1.05 g/L, more preferably 1g/L. In the embodiment of the invention, in the aspect of ethanol production, the experimental group with the crop straw concentration of 45g/L obtains the maximum concentration of ethanol of 1.64g/L and the maximum ethanol yield of 0.51g/L of unit straw.
In the invention, the hydrogen production kinetics of the two methods are also analyzed, in the one-step photo-fermentation hydrogen production, an experimental group with the straw concentration of 35g/L has higher hydrogen production rate, and an experimental group with the straw concentration of 45g/L has larger hydrogen production potential but larger delay period, and the photosynthesis of photosynthetic fermentation bacteria is slow. In the two-step hydrogen production experiment, the 25g/L experimental group has the maximum hydrogen production potential 356.26mL and the maximum hydrogen production rate 15.75mL/h, and compared with the one-step experimental group, the hydrogen production rate is improved by 2.6 times.
In the invention, the light conversion rate in the hydrogen production process is also analyzed, the maximum light conversion efficiency of the light fermentation hydrogen production is 9.35 percent of the straw concentration of 45g/L, and the minimum straw concentration is 5g/L. Compared with the light conversion efficiency of the one-step method, the light conversion efficiency of the two-step method reaches the maximum hydrogen production when the concentration of the straws is 25g/L, and simultaneously the maximum light conversion efficiency is 17.68%.
In the invention, the energy conversion efficiency is also analyzed, the maximum energy conversion efficiency of the one-step hydrogen conversion rate is 2.15% of the concentration of the straw at 25g/L, the photosynthetic conversion efficiency is 7.22% and is less than 9.35% of the concentration of the straw at 45 g/L. In the two-step hydrogen alcohol co-production, the highest hydrogen energy conversion efficiency of the corn stalk concentration of 25g/L is 5.34%.
The following describes in detail a method for producing hydrogen and producing ethanol by photosynthetic organisms from crop straw by combining the embodiments, but they should not be construed as limiting the scope of the invention.
Example 1
Combined production method for producing hydrogen by photosynthetic organisms and producing ethanol by organisms from corn stalks
1. Material
The substrate used in this test was a dry corn straw powder crushed to 60 mesh, the straw being from the university of agricultural in Henan, agricultural college.
Photo-fermentation biological hydrogen production strain: photosynthetic hydrogen-producing bacteria HAU-M1 (Jiang Danping, han Binxu, wang Yi, et al HAU-M1 analysis of physiological characteristics and hydrogen production characteristics of photosynthetic hydrogen-producing bacteria [ J ]. Solar journal 2015,36 (02): 289-294.) comes from the rural renewable energy materials and equipment key laboratory of the university of agricultural division in henna. It comprises rhodospirillum rubrum (Rhodospirillum rubrum) 27%, rhodopseudomonas capsulata (Rhodopseudomonas capsulate) 25%, rhodopseudomonas palustris (Rhodopseudomonaspalustris) 28%, rhodopseudomonas palustris (Rhodobactersphaeroides) 9% and rhodobacter sphaeroides (Rhodobacter capsulatus)11％([1]Lazaro CZ,Varesche MBA,and Silva EL.Effect of inoculum concentration,pH,light intensity and lighting regime on hydrogen production by phototrophic microbial consortium[J].Renewable Energy,2015,75:1-7.[2]Zhang ZP,Yue JZ,Zhou XH,et al.Photo-fermentative Bio-hydrogen Production from Agricultural Residue Enzymatic Hydrolyzate and the Enzyme Reuse[J].Bioresources,2014,9(2):2299-2310).
Biological ethanol preparation strain: brewing high-activity dry yeast; bioethanol microorganisms are purchased from Angel Yeast Co.
HAU-M1 growth medium: naHCO 31 g/L、NH4 Cl 0.5g/L, yeast extract 0.5g/L, K 2HPO40.1 g/L、CH3COONa 2g/L、MgSO4 0.1 g/L and NaCl 1g/L.
HAU-M1 hydrogen production medium: mgCl 20.2 g/L、NH4 Cl 0.4g/L, naCl g/L, sodium glutamate 3.56g/L, yeast extract 0.1g/L, K 2HPO4 0.5 g/L.
Liquid cellulase (51 FPU/mL, novozymes Biotechnology co., ltd, denmark).
2. Test method
(1) One-step photosynthetic organism hydrogen production and biological ethanol production co-production experiment: a200 mL conical flask is selected as a hydrogen production reaction vessel for co-production of hydrogen and alcohol by a one-step method. To the conical flask were added 1, 3, 5, 7, 9 and 11g of corn straw powder, respectively, followed by 50mL of the formulated and well mixed HAU-M1 hydrogen-producing medium solution and 100mLpH = 4.8 citric acid/sodium citrate buffer for stable pH adjustment. And the pH was adjusted using NaOH solution and sulfuric acid solution so that the pH of the fermentation broth in each conical flask was 7. In each conical flask, a corresponding amount of liquid cellulase was added dropwise in an amount of 0.4mL of cellulase per gram of substrate. 50mL of photosynthetic hydrogen-producing bacteria HAU-M1 in the growth phase at the late logarithmic phase and 0.2.+ -. 0.01g of dry yeast with brewing activity were added to each bioreactor. The prepared solution was placed in a constant temperature incubator at a temperature of 30.+ -. 2 ℃ and illuminance of 3000.+ -. 50 Lux. Recording is carried out every 12 hours until the gas production is stopped.
(2) Two-step photosynthetic organism hydrogen production and biological ethanol production co-production: similar to the one-step method, 1,3, 5, 7, 9 and 11g of corn stalk powder was added in 200mL conical flask, 50mL of the prepared and uniformly mixed hydrogen-producing medium solution and 100mL of citric acid/sodium citrate buffer solution with ph=4.8 were added, the pH was adjusted to 7, and 50mL of hydrogen-producing bacterium HAU-M1 was added to perform hydrogen-producing fermentation. The prepared solution was placed in a constant temperature incubator at a temperature of 30℃and an illuminance of 3000Lux, and the gas characteristics and the liquid characteristics of the test sample were measured and recorded at intervals of 12 hours. After the hydrogen production is finished, 0.2g of active dry yeast for brewing wine is respectively added into each experimental group, the conical flask is sealed, and the fermentation liquid is put into a dark fermentation box at 35 ℃ for continuous ethanol production fermentation, so that the two-step method hydrogen-alcohol co-production is realized. The gas characteristics and the liquid characteristics of the experimental samples are detected and recorded every 3 hours within 12 hours after the yeast is added, and the recording is performed every 12 hours after 12 hours until the gas production is stopped and the ethanol concentration has no obvious change.
Three replicates were run simultaneously for each set of experiments.
3. Detection method
The hydrogen content was determined using a model 6820GC-14B gas chromatograph. The carrier gas was nitrogen, column temperature 80 ℃, detector temperature 150 ℃. Ethanol concentration was measured using an Agilent gas chromatograph (7090B, USA), column box temperature 40 ℃, inlet and detector temperatures of 250 ℃ and 300 ℃, pressure 10psi, column flow 2.396mL/min, valve box temperature 44.1 ℃. The fermentation broth was measured for pH and redox potential using a pH meter (Metretolidol, switzerland) model FE28 and an ORP meter (Shanghai Sanxin Co., china) model SX721, respectively, using a DNS method with a reducing sugar concentration, and at OD 540nm using a U-T1810DSPC spectrophotometer (Shanghai Meter, inc., china).
2.4 Analysis of Hydrogen production kinetics and energy conversion efficiency
The energy conversion efficiency of the co-production fermentation of hydrogen and alcohol using corn stalks is given by the following formula (1):
Wherein: e is the energy conversion efficiency of the hydrogen alcohol co-production fermentation,%; m corn stalk is the mass of the corn stalk, g; m 1 is the mass of hydrogen produced by fermenting corn stalks, g; m 2 is the mass of ethanol produced by fermenting corn stalks, g; q Hydrogen gas ,Q Ethanol and Q corn stalk are the heat values of hydrogen, ethanol and corn stalks, which are 14300J/g,29696J/g and 17003J/g respectively.
The light conversion efficiency formula is calculated from formula (2):
Wherein: epsilon is the light conversion efficiency; ρ H2 is hydrogen density, g/L; v H2 is hydrogen volume; i is light intensity, W/m 2, where 1W/m 2 = 683lx; a is a light region, m 2; t is the total hydrogen production time, h.
And carrying out hydrogen production dynamics analysis on the accumulated hydrogen production by adopting a corrected Gompertz equation, wherein the analysis equation is shown as a formula (3):
Wherein: p H2 (t) is the accumulated hydrogen yield, mL; p max is the maximum hydrogen production potential, mL; r m is the maximum hydrogen production rate, mL/h; lambda is hydrogen production delay period, h; e is the base of natural logarithm, and takes the value of 2.718.
The energy conversion efficiency was calculated using Excel and statistical analysis of kinetic and anova was performed by Origin software. R 2 >0.98 shows a strong statistical significance.
3. Results and analysis
3.1 Analysis of Hydrogen-alcohol co-production characteristics by the next step method with different substrate concentrations
By analyzing the results of the next-step hydrogen-alcohol co-production experiment of different substrate concentrations, the trend of the volume fraction change of the hydrogen in the one-step hydrogen-alcohol co-production experiment is shown in the figure 1 (a), and when the substrate concentration is 25g/L, the volume fraction of the hydrogen is increased at a larger rate within 12-24h in the reaction process. When the substrate concentration is 5g/L, the volume fraction of hydrogen has no obvious acceleration change between 12 and 24 hours, and the gas production is stopped at 48 hours. The results showed that the maximum hydrogen volume fraction was 38.39% at a substrate concentration of 25g/L for all groups, which stopped the production of gas at 84h, due to the large amount of hydrogen production inhibitor produced in the latter stage of hydrogen production. With the increase of the volume fraction of the hydrogen, the area surrounded by the volume fraction curve of the hydrogen and the X axis is continuously increased, but when the concentration of the substrate is 5g/L, the area is not basically changed, and the straw content is too low, so that nutrition required by the propagation of the photosynthetic bacteria HAU-M1 cannot be provided, and the propagation of the photosynthetic bacteria stagnates and even die. Photosynthetic bacteria can obtain enough nutrition to maintain life activities at higher substrate concentrations to produce hydrogen. The maximum hydrogen volume fraction of 56.55% obtained by jin et al in the hydrogen production of corn stalk photosynthetic organisms is significantly higher than the maximum hydrogen volume fraction of 38.39% in the hydrogen-alcohol co-production by a one-step method, and the main analysis is that the experiment is the hydrogen-alcohol co-production by a one-step method, and yeast is added in the initial stage of the reaction, and the yeast consumes a certain amount of substrate, so that the hydrogen production volume fraction is reduced.
By analyzing the results of the next-step hydrogen alcohol co-production experiment with different substrate concentrations, the cumulative hydrogen production variation trend is shown in the graph (b) in fig. 1, and the cumulative hydrogen production obtained in 60h in the reaction process of all experiment groups is continuously increased, and the higher the substrate concentration is, the higher the cumulative hydrogen production is. The minimum value of the accumulated hydrogen yield in the experimental group with 5g/L is 1.10mL, and the maximum value of the accumulated hydrogen yield in the experimental group with 45g/L is 185.17mL. The results show that a higher substrate concentration can increase the cumulative hydrogen production while the maximum hydrogen production per straw observed at a substrate concentration of 25g/L is 28.60mL/g. However, in the course of going from the 5g/L experimental group to the 45g/L experimental group, the cumulative hydrogen production increases with increasing concentration, and then the trend is changed inversely, because the substrate concentration is too high, causing rapid deterioration of the hydrogen production environment, for example, because the activity of photosynthetic bacteria is inhibited due to rapid decrease of the pH value, further reducing the hydrogen production capacity, and further causing decrease of the cumulative hydrogen production.
The trend of the oxidation-reduction potential was as shown in FIG. 1 (c), and the oxidation-reduction potential was drastically decreased during the whole experimental group reaction for 0to 12 hours, followed by a slight rise and then a slight fluctuation of the oxidation-reduction potential. The highest redox potential value is-172 mV after 60 hours of 55g/L experimental group reaction, and the lowest redox potential value is-433 mV after 60 hours of 45g/L experimental group reaction. The oxidation-reduction potential is rapidly reduced within 0-12h, and the reduction of the oxidation-reduction potential can infer that the reduction is stronger at the moment, thereby being more beneficial to the biochemical reaction.
The trend of pH change is shown in FIG. 1 (d). Different experimental groups show a tendency of overall decrease in pH as the concentration of straw increases. The pH value during the reaction of all experimental groups was first reduced rapidly and then essentially unchanged. The pH of the 25g/L experimental group was reduced from 7 to 5.56 in 24h, and finally stabilized around 6.0. The pH of the 55g/L experimental group was reduced from 4.94 to 4.78 in 24-96 hours. The pH of the 5g/L experimental group was reduced to a minimum of 6.14 over a period of 24 hours. Experimental results show that the speed of the degradation of the corn stalks into hydrogen and the consumption of fatty acid in the soluble substances of the soluble substances is higher than the speed of the output of fatty acid in the first 24 hours of the hydrogen production reaction. The reason is that photosynthetic microorganisms can convert organic substances in the straw into products such as hydrogen, organic acid and the like in the straw fermentation process. The production of organic acids increases the acidity in the solution. With the progress of the reaction, the pH value decreases. This phenomenon is caused by the fact that when the concentration of the straw is low, macromolecular organic substances are consumed by hydrogen and acid production, so that no new organic acid is produced, the pH value is basically unchanged, and the pH value is basically stabilized at 7.0.
The reducing sugar concentration change trend is shown in the (e) of the figure 1, the reducing sugar concentration increases along with the increase of the corn straw concentration, the maximum reducing sugar concentration value is obtained by each experimental group at 12 hours, the reducing sugar concentration is reduced at a higher speed within 12-24 hours of the experiment, and the reducing sugar concentration is not changed basically after 36 hours. Wherein the 55g/L experimental group obtained a maximum reducing sugar concentration of 5.95g/L at 12 h. Experimental results show that the corn stalk concentration can obtain higher reducing sugar concentration when the corn stalk concentration is higher. The maximum reducing sugar value of each group is increased along with the substrate concentration, but the reducing sugar concentration is obviously reduced due to the fact that photosynthetic bacteria can quickly degrade nutrients such as reducing sugar to produce hydrogen and organic acid, and saccharomycetes degrade reducing sugar to ethanol.
By analyzing the results of the next-step hydrogen alcohol co-production experiment of different substrate concentrations, the trend of the change of the ethanol concentration is shown in (f) in fig. 1, the higher the substrate concentration is, the higher the concentration of the soluble substances is, because the photosynthetic bacteria producing hydrogen by photo-fermentation can degrade additional substrates for metabolism. The ethanol concentration of the 5g/L experimental group was almost zero. This indicates that at lower substrate concentrations, the metabolic pathway of volatile fatty acids is superior to ethanol. The maximum concentration of ethanol obtained by the 55g/L experimental group is 7.09g/L, and the maximum ethanol yield per unit straw is 0.74g/L. With the increase of the concentration of the straw, the concentration of the soluble substances shows a continuous rising trend, wherein the concentration of the ethanol shows a remarkable rising trend, and the concentration of the soluble fatty acid is basically kept unchanged. Too high a straw concentration will inhibit further elevation of ethanol concentration due to the inhibitory substances produced by the high concentration of substrate. After the yeast is added, saccharification and fermentation of the straw are carried out simultaneously, so that the inhibition effect of high-concentration substrates on cellulose hydrolysis and independent fermentation can be effectively relieved. The 5g/L experimental group obtained the smallest ethanol concentration of 0.62g/L, and the 55g/L experimental group obtained the largest ethanol concentration of 7.09g/L.
3.2 Two-step method for hydrogen-alcohol co-production characteristic analysis under different substrate concentrations
The variation trend of the volume fraction of the co-produced hydrogen of the corn stalks and the hydrogen alcohols with different substrate concentrations is shown in the figure 2 (a). When the concentration of the corn stalk substrate is 25g/L, the hydrogen content of the fermentation solution is highest, and the highest value is 43.83%. When the concentration of the corn stalk substrate is 55g/L, the maximum hydrogen content of the fermentation solution is the lowest in the rest control fermentation solution, and the hydrogen production content is only 9.90%. All experimental groups stopped producing gas at 84h, respectively. Experimental results show that at the beginning of the reaction, corn stalks are slowly decomposed, the available nutrient substances of photosynthetic bacteria are less, the concentration of reducing sugar reaches the peak at 12 hours, the hydrogen production amount begins to increase, the hydrogen production is increased, and after 60 hours, the hydrogen production begins to rapidly decrease, and when the reaction reaches the later stage, the hydrogen production is stopped along with the consumption of the reducing sugar, because the nutrient substances of the photosynthetic bacteria are basically completely utilized.
The effect of co-production of hydrogen alcohol on cumulative hydrogen production at different substrate concentrations is shown in fig. 2 (b). The cumulative hydrogen production of the experimental group of 5g/L is only 22.20mL at the lowest. The accumulated hydrogen yield of the fermentation liquid with the substrate concentration of 25g/L is optimal, the accumulated hydrogen yield is 350.08mL at the highest, and meanwhile, the accumulated hydrogen yield of the fermentation liquid with the substrate concentration of 25g/L is 70.02mL/g, which is slightly higher than the final unit yield of the accumulated hydrogen yield of the dark fermentation. The results showed that as the substrate concentration increased from 5g/L to 25g/L, the cumulative hydrogen production increased continuously with increasing corn stover, but then the trend was reversed. The reason is that when the substrate concentration is too high, the hydrogen production environment is rapidly deteriorated, the pH value is rapidly reduced to inhibit the activity of photosynthetic bacteria, and the hydrogen production is further reduced, so that the accumulated hydrogen production is reduced.
The variation trend of the co-production oxidation-reduction potential of the corn stalk hydrogen alcohol with different substrate concentrations is shown in the figure 2 (c). The oxidation-reduction potential before the end of hydrogen production is changed Cheng Bolang, the highest oxidation-reduction potential value is-9 mV after 120 hours of 5g/L experimental group reaction, and the lowest oxidation-reduction potential value is-368 mV after 36 hours of 25g/L experimental group reaction. The results showed that the end of hydrogen production substrate concentration was between-9 mV and-176 mV for all redox potentials. In the process of producing hydrogen by fermentation, in order to ensure the reaction of anaerobic fermentation microorganisms, fermentation liquor is carried out in an environment with low oxidation-reduction potential. Various researches indicate that the oxidation-reduction potential can be fluctuated in the fermentation process, the fluctuated oxidation-reduction potential can be fluctuated in the hydrogen production process due to the fact that electrons are lost and transferred in the hydrogen production process, partial oxygen is consumed in the fermentation process to enhance the reducibility of the hydrogen production process to carry out higher accumulation, and the oxidation-reduction potential can be low in the hydrogen production peak, so that the fluctuation phenomenon of the oxidation-reduction potential can be generated. The final redox potential of the end-of-hydrogen-production experimental solution eventually stabilized between-116 mV and-11 mV. In the process of producing ethanol, electrons are lost and lost in oxidation-reduction potential, and saccharomycetes have better activity between-50 mV and-150 mV in the growth environment, so that reducing sugar in fermentation liquor can be better oxidized and decomposed into ethanol.
The pH variation trend of the co-production of hydrogen alcohol by the two-step method of corn stalks with different substrate concentrations is shown in the figure 2 (d). The pH is reduced and then increased, because when cellulose breaks down the corn stover, the corn stover is degraded into macromolecular sugars, which in turn are degraded into small molecular acids. Therefore, the fermentation liquid shows acidity in the hydrogen production process, and the higher the concentration of the corn stalks is, the stronger the acidity is. The pH initially drops rapidly and after 24 hours the pH is stable. In the alcohol production stage, the pH of the substrate concentration is 5g/L, the pH is overall higher, and the maximum value of the pH is 7.95 at 72h of alcohol production. The pH of the reaction solution was the lowest at 48h, the pH of the reaction solution was 4.13, and the final pH of the test solutions at the end of 96 h for alcohol production at 5, 15, 25, 35, 45 and 55g/L at the end of 96 h for yeast addition were 7.66, 6.2, 6.03, 5.8, 5.91 and 4.23, respectively. After alcohol production, the pH of the corn stover was the lowest at a concentration of 55 g/L. This is because the hydrogen production is too low, and a large amount of small molecular acid contained in the solution consumes a part of reducing sugar in the ethanol production process and continues to produce a part of small molecular acid, so that the pH continues to be reduced, and an acidic environment is shown. Meanwhile, too low acidity can inhibit the growth and propagation of yeast, and influence the activity of the yeast.
The variation trend of the concentration of the reducing sugar before the co-production of the corn stalk hydrogen alcohol with different substrate concentrations is finished is shown in the (d) of the figure 2. The concentration of reducing sugar increases with the increase of the concentration of the corn stalks before the end of hydrogen production, and the maximum reducing sugar concentration value is obtained in each experimental group at 12h, wherein the substrate concentration is 55g/L, and the maximum reducing sugar concentration is 6.05g/L. At 96h, the minimum value achieved at this time for the substrate concentration of 5g/L of the test group of reducing sugars was 0.412g/L. The basis of nutrient substances in the corn stalks is a necessary condition for producing hydrogen and ethanol. In the hydrogen production process, the higher the concentration of the corn straw is, the more the content of the reducing sugar is, the cellulose is used for degrading lignin in the corn straw, the content of the reducing sugar is rapidly reduced after 12 hours, the reducing sugar is greatly consumed because the reaction liquid generates hydrogen under the action of photosynthetic bacteria, and the content of the reducing sugar tends to be stable at 36 hours, because the rate of reducing sugar consumed in hydrogen production is basically equal to that of reducing sugar decomposed by the corn straw by the cellulose.
When alcohol is produced, the content of reducing sugar in fermentation liquor is increased along with the increase of straw concentration, compared with the content of reducing sugar in hydrogen production, the total content of reducing sugar in all fermentation liquor is slightly reduced after yeast is added, and glucose is consumed by yeast to produce ethanol, but the content of reducing sugar is slowly reduced, besides the factors of slow decomposition of corn straw, the reducing sugar is greatly consumed in the hydrogen production stage, so that the reducing sugar is less in the ethanol production stage, and the content of reducing sugar quickly tends to balance after being reduced in a short time. At the moment, the reducing sugar content is lower, the straw content of the fermentation liquor with the straw concentration of 55g/L is highest, the reducing sugar content is higher during ethanol fermentation, and the ethanol production concentration is relatively highest.
The concentration change of the co-production ethanol of the corn stalks with different substrate concentrations is shown in (f) of fig. 2. After the hydrogen production is completed for 84 hours, the concentration of the ethanol in the experimental group with the concentration of the straw of 5g/L is lower, and the minimum concentration of the ethanol is 0.18g/L. Before yeast is added, the maximum concentration of ethanol obtained by an experimental group with the concentration of the straw of 45g/L is 1.64g/L, and the maximum ethanol yield per unit straw is 0.51g/L. After yeast addition, the maximum ethanol concentration of the 45g/L experimental group was 1.87g/L, which was only 11.40% higher than that of the ethanol concentration without yeast addition. This may be due to the accumulation of small molecular acids in the hydrogen production process of the straw, which results in too low pH, difficulty in yeast reproduction, and influence on the activity of the yeast. Meanwhile, the concentration of the ethanol in the fermentation liquid is increased by 13.89% when the concentration of the straw is 25g/L, and the concentration of the ethanol is not the maximum but is higher than the lifting rate of the maximum concentration of the ethanol, probably because the pH of the fermentation liquid with the concentration of the straw of 25g/L is more stable, and the activity of saccharomycetes in the pH range is also more stable. Too high a concentration of straw, the ethanol conversion efficiency is also reduced, because the too high concentration of straw can produce a part of fermentation inhibitor for decomposing and fermenting the straw to further influence the ethanol fermentation.
3.3 Analysis of Hydrogen production kinetics
TABLE 1 simulation parameters of hydrogen production kinetics
Kinetic parameters obtained from the Gompertz model are shown in Table 1, and according to hydrogen production kinetic analysis, the maximum hydrogen potential of corn straw concentration of 5g/L to 25g/L increases with increasing straw concentration, and then the tendency of decrease occurs. In the one-step photo-fermentation hydrogen production, the experimental group with the straw concentration of 35g/L has higher hydrogen production rate, and the experimental group with the straw concentration of 45g/L has larger hydrogen production potential but larger delay period, and the photosynthesis of the photosynthetic fermentation bacteria is slow.
In the two-step hydrogen production experiment, the 25g/L experimental group has the maximum hydrogen production potential 356.26mL and the maximum hydrogen production rate 15.75mL/h, and compared with the one-step experimental group, the hydrogen production rate is improved by 2.6 times. The maximum hydrogen yield of the experimental group is also increased and then reduced with the increase of the straw concentration, and the result is similar to that of a one-step method. The calculated and predicted maximum hydrogen production potential is basically consistent with the experimental result, and R 2 in the one-step method and the two-step method is larger than 0.98, which shows that the Gompertz model can be well fit with hydrogen production data.
3.4 Light conversion efficiency
And (3) calculating the light conversion efficiency in the photosynthetic hydrogen production process according to the formula (2). The light conversion efficiency in the one-step hydrogen alcohol co-production is shown in fig. 3 (a), and interestingly, the maximum light conversion efficiency of the light fermentation hydrogen production is 9.35% of the straw concentration of 45g/L, and the minimum light conversion efficiency is only 0.06% of the straw concentration of 5g/L, which is probably due to the fact that the light co-production hydrogen bacteria can use less energy substances when the straw concentration is too low in the co-fermentation of photosynthetic hydrogen producing bacteria and yeast bacteria, the light conversion is very low, and the optimal one-step hydrogen alcohol co-production hydrogen production concentration is achieved when the concentration reaches 45 g/L.
The light conversion efficiency of the two-step method is shown in fig. 3 (b), and compared with the light conversion efficiency of the one-step method, the light conversion efficiency of the two-step method reaches the maximum hydrogen production when the concentration of the straw is 25g/L, and simultaneously the maximum light conversion efficiency is 17.68%. The photosynthetic fermentation of the straw is in the same environment, the light energy is utilized by photosynthetic hydrogen-producing bacteria to produce hydrogen, and the light conversion efficiency of the hydrogen is not neglected while the economy is considered.
3.5 Energy conversion efficiency analysis
And (3) calculating the energy conversion efficiency of producing hydrogen and ethanol by fermenting the corn straw according to the formula (1). The energy conversion efficiency of the one-step hydrogen alcohol co-production is shown in (a) of fig. 4, the one-step hydrogen conversion rate is low, the maximum hydrogen energy conversion efficiency is 2.15% of the straw concentration of 25g/L, the photosynthetic conversion efficiency is 7.22%, and the energy conversion efficiency is less than 9.35% of the straw concentration of 45 g/L. As more ethanol is produced by the hydrogen alcohol co-production of the one-step method, the heat value of the ethanol is higher, and the generation of hydrogen is inhibited, the total energy conversion efficiency of the one-step method is higher than that of the two-step method, the highest total energy conversion efficiency is 25.88 percent of the straw concentration of 5g/L, and compared with the two-step method, the energy conversion efficiency is improved by 8.1 percent. The reason is that the energy of the ethanol is higher, and compared with pure hydrogen production, the conversion efficiency of the corn straw is improved when the ethanol is produced.
The energy conversion efficiency of the co-production of hydrogen and alcohol by the two-step method is shown in (b) of fig. 4, the highest energy conversion efficiency of hydrogen with the concentration of 25g/L of corn straw is 5.34%, the light conversion efficiency of the photo-fermentation hydrogen production has the highest light conversion efficiency of 17.68% when the concentration of the straw is 25g/L, and the maximum conversion efficiency of the one-step method is 8.33%. When the concentration of the straw reaches 5g/L, the maximum energy conversion efficiency reaches 17.79 percent. The practical economy of ethanol is to be commercially established because of its low concentration and some difficulty in extraction.
The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.
Claims (10)
1. The combined production method for producing hydrogen and ethanol by photosynthetic organisms of crop straws is characterized by comprising the following steps of:
taking a hydrogen production culture medium containing crop straw powder as a fermentation culture medium, and inoculating cellulase, photosynthetic hydrogen production bacteria HAU-M1 and active dry yeast for brewing to ferment;
The concentration of the crop straw powder is 5-55 g/L.
2. The co-production method according to claim 1, wherein the photosynthetic hydrogen-producing bacterium HAU-M1 and the Saccharomyces cerevisiae active dry yeast are simultaneously inoculated into the fermentation medium.
3. The co-production method according to claim 2, wherein the fermentation time is 12 to 84 hours;
the initial pH value of the fermentation is 6.8-7.2;
the fermentation temperature is 28-32 ℃;
The illumination intensity of the fermentation is preferably 2950-3050 Lux.
4. The combined production method according to claim 1, wherein the photosynthetic hydrogen-producing bacterium HAU-M1 is inoculated into a fermentation medium for hydrogen-producing fermentation, and then inoculated with active dry yeast for brewing alcohol fermentation after the hydrogen-producing fermentation is completed.
5. The method according to claim 4, wherein the hydrogen-producing fermentation time is 12 to 84 hours;
The initial pH value of the hydrogen-producing fermentation is 6.8-7.2;
the temperature of the hydrogen production fermentation is 28-32 ℃;
The illumination intensity of the hydrogen-producing fermentation is 2950-3050 Lux.
6. The joint production method according to claim 4, wherein the time of ethanol fermentation is 3 to 36 hours;
the temperature of the ethanol fermentation is 34-36 ℃;
and fermenting the ethanol in a dark place.
7. The joint production method according to claim 1, wherein the inoculation amount of the photosynthetic hydrogen producing bacteria HAU-M1 is 20% to 30%;
the inoculation amount of the active dry yeast for brewing wine is 0.95-1.05 g/L.
8. The co-production method according to any one of claims 1 to 7, wherein the concentration of the crop straw powder is 15 to 45g/L.
9. The combination production method according to claim 8, wherein the crop species includes at least one of: corn stalks, wheat stalks, rice stalks and peanut vines.
10. The co-production method according to any one of claims 1 to 7 and 9, wherein the cellulase is added in an amount of 0.39 to 0.41mL/g straw.
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