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CN-121747726-B - Deep CO of coal2Construction method and application of synthetic ecological network of storage area

CN121747726BCN 121747726 BCN121747726 BCN 121747726BCN-121747726-B

Abstract

The invention provides a synthetic ecological network construction method and application of a coal deep CO 2 sealing area, and belongs to the technical field of bioengineering and carbon sealing. The method comprises the steps of constructing a coexisting network based on in-situ microorganism data, identifying a functional target according to topological properties, designing a preliminary synthesis network scheme comprising four modules including environmental buffering, substrate processing, electron transfer enhancement and methanogenic core aiming at the target, co-culturing the scheme and a representative original colony in a system simulating extreme conditions of a stratum, monitoring a cooperative operation state, evaluating according to a preset cooperative stability criterion, and if the evaluation fails, feeding back to the previous step according to failure analysis to perform parameter optimization until a final design scheme meeting long-term cooperative stability requirements is obtained. According to the invention, through closed-loop dynamic optimization, the cooperative stabilization of a synthetic network and a primary community is realized, and the long-term reliability and the system robustness of biological methane production under the CO 2 sealing and storing environment in the deep part of coal are improved.

Inventors

  • LI YANG
  • LI NA
  • Yan xinyue
  • YAO TINGTING

Assignees

  • 安徽理工大学

Dates

Publication Date
20260512
Application Date
20260224

Claims (5)

  1. 1. The method for constructing the synthetic ecological network of the deep CO 2 storage area of the coal is characterized by comprising the following steps of: Step S1, determining a functional target point for introducing exogenous synthesis ecological network integration based on in-situ microbial community data of a target coal seam; s2, designing a preliminary synthetic ecological network design scheme; Step S3, the preliminary synthetic ecological network design scheme and a representative primary microorganism group of a target coal seam are CO-cultured in a system simulating a deep CO 2 sealing environment, and the cooperative operation state of the preliminary synthetic ecological network design scheme and the representative primary microorganism group is monitored; S4, evaluating the cooperative stability of the synthesized ecological network and the primary community according to the monitoring data; step S5, if the evaluation does not meet the collaborative stability criterion, returning to adjust the target spot screening strategy of the step S1 and the preliminary synthetic ecological network design scheme of the step S2 according to collaborative failure analysis, and re-verifying until a final synthetic ecological network design scheme meeting the collaborative stability criterion is obtained; the step S1 specifically comprises the following steps: S11, acquiring an in-situ microorganism sample of a target coal seam, and performing high-throughput sequencing to acquire species composition data; Step S12, constructing a microorganism coexistence network by adopting SparCC algorithm based on species composition data; step S13, calculating the intra-module connectivity of each node in the microbial coexistence network Value and inter-module connectivity A value; Step S14, according to Value sum A value identifying the network location of the node satisfying one of the following conditions as a functional target point, namely the connectivity between modules Network connection weaknesses with a value of less than 0.5, or intra-module connectivity A potential function enhancing region having a value of greater than 2.5 and a relative abundance of methanogenic archaea mcrA gene within the module of less than 1%; the step S2 specifically comprises the following steps: step S21, defining the functions of an environment buffer module, a substrate processing module, an electronic transmission strengthening module and a methanogenic core module according to the functional targets identified in the step S1; step S22, screening or designing strains which can form metabolic complements with the primary community, and distributing the strains to corresponding modules; step S23, calculating and determining inoculation proportion of strains in each module and among modules by taking maximization of methane yield and minimization of metabolic intermediate accumulation as optimization targets; step S24, outputting a preliminary synthetic ecological network design scheme comprising specific strain composition, module attribution and inoculation proportion; In step S5, the feedback optimization rule according to the collaborative failure analysis specifically includes: if the methane yield fluctuation coefficient criterion is violated, returning to the step S1, and screening the connectivity among the modules The threshold value of the value increases from 0.5 to 0.7; if the metabolic intermediate criterion is violated, returning to the step S2 to re-screen or verify the strain by improving the tolerance standard to the key metabolic intermediate, or returning to the step S23 to up-regulate the cell number ratio of the strain of the substrate processing module to the methanogenic core module; If the stability criterion of the bacterial flora is violated, returning to the step S2, increasing the survival rate verification of the bacterial strain under the condition of pH3.5, or returning to the step S23, and increasing the inoculation proportion of the environmental buffer module.
  2. 2. The method for constructing a synthetic ecological network in a deep CO 2 sequestration area of coal according to claim 1, wherein an environmental buffer module is used for secreting extracellular polymers and adjusting the pH of the micro-area to be above 5.0, a substrate processing module is used for degrading and converting aromatic compounds of coal sources into hydrogen, carbon dioxide and acetic acid, an electron transfer enhancement module is used for improving electron flux through electron transfer or soluble electron shuttling between direct inoculation, and a methanogenic core module is used for converting substrates into methane through hydrogen nutrition type and acetic acid nutrition type pathways.
  3. 3. The method for constructing a synthetic ecological network of a deep CO 2 sequestration area of coal according to claim 1, wherein step S3 specifically includes: Step S31, according to the design scheme of the primary synthetic ecological network output in the step S24, inoculating the primary synthetic ecological network with a representative primary microorganism community, and maintaining the environmental condition for simulating deep CO 2 sealing; Step S32, continuously monitoring metabolite indexes, environment indexes and flora abundance indexes of the co-culture system to evaluate a cooperative operation state; wherein the metabolite indicators include methane yield, acetic acid concentration, and dissolved hydrogen concentration; Environmental indicators include pH; the flora abundance index includes the gene copy numbers of the synthetic network marker strain and the methanogenic archaea as determined by quantitative PCR.
  4. 4. The method for constructing a synthetic ecological network of a deep coal CO 2 sequestration area according to claim 3, wherein in step S4, the synergistic function long-term stability criterion includes: methane yield fluctuation coefficient criterion, namely the methane yield fluctuation coefficient from 15 th day to 30 th day of the monitoring period is less than or equal to 15%; The metabolic intermediate product criterion is that the concentration of acetic acid is lower than 50mg/L in the monitoring period; The flora stability criterion is that the attenuation amplitude of the gene copy number of the synthetic network marker strain is not more than 1 order of magnitude.
  5. 5. Use of a synthetic ecological network constructed according to the method of any one of claims 1 to 4 for enhancing long-term synergistic stability of a biological methane conversion process in a deep coal seam CO 2 sequestration area, characterized in that after a final synthetic ecological network design is obtained, all functional strains in the final synthetic ecological network design are CO-cultured and amplified, and combined with a slow-release carrier composed of calcium alginate and activated carbon, to prepare a solid microsphere ecological preparation with a particle size of 2mm to 5 mm.

Description

Construction method and application of synthetic ecological network of deep CO 2 storage area of coal Technical Field The invention relates to the technical field of bioengineering and carbon sequestration, in particular to a synthetic ecological network construction method and application of a deep CO 2 sequestration area of coal. Background Carbon dioxide (CO 2) is injected into a deep coal-non-mining layer for geological sequestration, and is converted into methane by means of the action of microorganisms, so that the method is a promising carbon emission reduction and energy recovery technology. However, the deep sealing environment usually has multiple extreme conditions such as high pressure, strong acid and supercritical CO 2 fluid, and the survival and metabolism of microorganisms are seriously inhibited, so that the biological methanogenesis process is low in efficiency and difficult to stably maintain for a long time. This is a core bottleneck limiting the development of this technology. Currently, two main technical ideas exist for solving this problem. Firstly, the environment is regulated by injecting nutrient solution or chemical reagent, but the method has extensive and short effect, and can not fundamentally maintain the steady state of the microbial community. Secondly, exogenous domesticated functional flora is directly introduced into the underground, but the method often neglects the compatibility of the original complex original microorganism ecological system in the underground. The introduced flora may not be colonised due to competition exclusion or niche conflict, and its metabolic activity may even interfere with the function of the original flora, eventually leading to a decline or failure of the gas producing function of the whole system after a period of operation. A further limitation is that existing methods of flora construction and optimization are mostly of open loop static design. These methods usually complete a one-time design under standard laboratory conditions, and lack the key links for performing collaborative function verification and iterative optimization in a system simulating the extreme environment of a real stratum and containing a primary community. Thus, it is difficult in the prior art to ensure that the constructed microbial system is capable of achieving long-term stable co-operation with the primary community in a practical underground environment. Disclosure of Invention The invention aims to provide a synthetic ecological network construction method and application of a deep CO 2 storage area of coal, which solve the defects of the existing open-loop static design, and a functional module which can be cooperated and stabilized with an underground in-situ microbial ecological system for a long time is constructed in a rational design, experimental verification and iterative feedback mode by establishing a closed-loop dynamic optimization method facing a primary community, so that the sustainability and reliability of a biological methane production process under the deep CO 2 storage environment are ensured. In order to achieve the purpose, the invention provides a method for constructing a synthetic ecological network of a coal deep CO 2 storage area, which comprises the following steps: Step S1, determining a functional target point for introducing exogenous synthesis ecological network integration based on in-situ microbial community data of a target coal seam; s2, designing a preliminary synthetic ecological network design scheme; Step S3, the preliminary synthetic ecological network design scheme and a representative primary microorganism group of a target coal seam are CO-cultured in a system simulating a deep CO 2 sealing environment, and the cooperative operation state of the preliminary synthetic ecological network design scheme and the representative primary microorganism group is monitored; S4, evaluating the cooperative stability of the synthesized ecological network and the primary community according to the monitoring data; and S5, if the evaluation does not meet the collaborative stability criterion, returning to adjust the target spot screening strategy of the step S1 and the preliminary synthetic ecological network design scheme of the step S2 according to collaborative failure analysis, and re-verifying until the final synthetic ecological network design scheme meeting the collaborative stability criterion is obtained. Preferably, step S1 specifically includes: S11, acquiring an in-situ microorganism sample of a target coal seam, and performing high-throughput sequencing to acquire species composition data; Step S12, constructing a microorganism coexistence network by adopting SparCC algorithm based on species composition data; step S13, calculating the intra-module connectivity of each node in the microbial coexistence network Value and inter-module connectivityA value; Step S14, according to Value sumA value identifying the network