Boiler dust emission concentration measuring method and system

The invention discloses a boiler dust emission concentration measuring method and system. The boiler dust emission concentration measuring method comprises the steps that a boiler comprises a boiler body and a flue communicated with the boiler body. The flue is connected with a dry dust collector, a wet desulphurization device and a wet dust collector which are arranged in sequence. The dust emission concentration measuring method comprises the following steps that the dust concentration mo produced after fuel is combusted is measured at an inlet of the dry dust collector; the concentration md of impurities brought out by desulphurization liquid drops is measured at an outlet of the wet desulphurization device; the dust collection efficiency etasp of the dry dust collector, the dust collection efficiency etasn of the wet desulphurization device and the dust collection efficiency etaw of the wet dust collector are obtained; the dust emission concentration me is figured out based on the formula: me=[mo*(1-etasp)*(1-etasn)+md]*(1-etaw), and the dust collection efficiency etasn of the wet desulphurization device and the concentration md of the impurities brought out by the desulphurization liquid drops are added into the calculation formula of the dust emission concentration me, so that the obtained result is more consistent with the reality, and the calculation precision is higher.