The combination of CO2 regeneration from CO2-rich solvent and atmospheric CO2 content increment in the agricultural greenhouse was explored when the membrane-based air stripping technology and CO2-rich potassium glycinate (PG) were adopted. Additionally, the method of CO2 content increase for tomato growth in the greenhouse was also put forward. Results showed that an increase of the initial CO2 loading of CO2-rich PG solution straight forwardly increased the CO2 regeneration efficiency and then the released CO2 amount under the conditions of 40~80℃ reaction temperature. A regeneration equilibrium can be obtained within 60minutes. Under the optimal operating conditions of 6L/min air stripping flow rate, 0.75mol/mol initial CO2 loading and 60minutes regeneration time, the released CO2 amount can be easily controlled only by regulating the rich PG solvent flow rate and regeneration temperature. Two approaches for increasing the atmospheric CO2 content in a standard greenhouse (600m3) were provided for improving the growth of tomato. Firstly, the atmospheric CO2 content was rapidly increased to the maximum value through CO2 regeneration from rich PG solvent, and then the required CO2 amount during tomato growth was supplemented according to the plant photosynthesis. Secondly, based on the calculation of total CO2 amount required for tomato growth in some times, CO2 form rich solvent regeneration was supplemented into the greenhouse at a fixed speed. Compared with the traditional method, this method using CO2 released from CO2-rich solvent as CO2 gas-fertilizer can obtain a lower cost and environmental sensitivity. For example, the CO2 generation cost can reduce by up to about 58.00%. For a bio-natural gas plant with 1000m3/d biogas yield, the released CO2 during biogas upgrading can be completely absorbed and fixed by the plants cultivated in the three multi-span greenhouses when the developed technology was used.