Sampling and preparation system and its implementation method

A sampling and preparation method used for measuring 14C in a boiler flue of a coal and biomass co-fired power station, comprising the following acts:

• filtering and fixing step:
• filtering particulate matter and water in flue gas from the boiler flue, and fixing carbon dioxide of the filtered flue gas in a carbon dioxide trap;
• flue gas measuring step:
• obtaining an amount of the filtered flue gas entering the carbon dioxide trap by a mass flow controller;
• transferring step:
• transferring the carbon dioxide from the carbon dioxide trap into the 14C testing device, comprising the following sub-act:
• pretreating the carbon dioxide to a liquid or supercritical state;
• and
• 14C testing step:
• measuring the 14C of the carbon dioxide in the 14C testing device.

A sampling and preparation system used for measuring a blending ratio of a coal and biomass co-fired power station, comprising:

• a sampling pipe connectable with a boiler flue of a co-fired power station, wherein the sampling pipe comprises the following elements sequentially arranged from an end close to the boiler flue to another end away from the boiler flue:
• a filtering device, a mass flow controller, a carbon dioxide trap and a pumping device;
• a carbon dioxide transferring device;
• and
• a 14C testing device, the carbon dioxide transferring device being arranged to transfer carbon dioxide from the carbon dioxide trap into the 14C testing device, and the 14C testing device is configured to measure 14C in the carbon dioxide,
• wherein:
• the 14C testing device comprises an optical fiber, a scintillation counter and a14C testing bottle;
• the 14C testing bottle comprises a pressure-bearing shell and a sample bin positioned in the pressure-bearing shell, a cavity is arranged in the sample bin and the 14C testing bottle is provided with an injection port connected to the cavity;
• the injection port is connected with the transferring device;
• the sample bin is configured to diffuse light produced in the cavity;
• a scintillator is preset in the cavity;
• at least part of the sample bin is transparent, an optical fiber channel is set on the pressure-bearing shell, wherein one end of the optical fiber channel is connected with the scintillation counter and another end of the optical fiber channel is connected with the transparent part of the sample bin;
• an insulation layer is positioned between the pressure-bearing shell and the simple bin;
• a sensory assembly is positioned in the cavity and the sensory assembly is a pressure sensor and/or a temperature sensor;
• the cavity is spherical or cylindrical;
• one end of the optical fiber is inserted into the optical fiber channel of the 14C testing bottle, and another end of the optical fiber is connected to the scintillation counter.