The fouling and slagging phenomena usually occur on heating surface of coal-fired boilers, and the problem of fouling becomes more serious when the boiling fires high ash and high sulfur content coal. To solve this problem, the advantages and disadvantages of the existing cleaning devices were analyzed. On this basis, a new type of steam pulsed acoustic dust cleaning device was developed in this paper. The three-dimensional flow path of the cleaning device was built. Combined with the principle of acoustic cleaning, the relationship between the total pressure drop of the fluid and the opening degree as well as the change trend of the pressure and velocity in the flow field were analyzed in detail. Finally, part of the key data of the power plant before and after the new cleaning device was put into service was compared, and the economic and environmental benefits were calculated. The results show that, the pressure and velocity pulsation are generated at each point in the fluid domain when the opening degree of the settler is changed. During this process, the mechanical energy of the fluid is converted into pulsed wave oscillation to realize cleaning. After the cleaning device is installed on the boiler, the exhaust temperature decreases by an average of 16.35℃ and no low temperature corrosion is observed. The annual coal conservation and steam conversation are 1 650 t and 21 192 t, The annual emission reduction of CO2 and SO2 are 726 t and 33 t respectively. In addition, it can also reduce the soot and slag emission by 25 t and 429 t each year. The money saved due to coal consumption is more than 1.6 million yuan per year and the annual economic benefit is 980 000 yuan.
Thermal Power Generation
boiler, heating surface, ash deposition, low frequency sound wave, acoustic ash cleaning, soot blowingsystem, energy saving and emission reduction, economic benifit