Dust removal:

Pre-dust using multi-tube dust collectors, and in the subsequent one and two-layer water filter water beds, multi-stage wet fine dust removal is also set up.

B. Nitrogen Oxide Removal

Using ferrous sulfate to absorb nitrogen oxides from flue gas, in a single-layer water filter-type water bed, the oxygen atom in NO is complexed and absorbed by divalent iron ions to form ferric nitrite sulfate, thereby reducing N to N2 and releasing it back into the atmosphere. During the denitrification process, the Fe2+ in the water is oxidized to Fe3+ by NO in the flue gas and residual O2, and Fe3+ has no affinity with H2O, so it cannot continue denitrification, and the denitrification capacity of the water body will gradually weaken. To maintain the denitrification activity of the water body, a reducing agent—iron shavings—is added. The NO in the flue gas is complexed and absorbed into the liquid phase by the ferrous ions in the ferrous sulfate solution, and the ferric nitrite sulfate formed can be reduced by elemental iron, while the elemental iron itself is oxidized to Fe2+. The iron shavings can also reduce Fe3+ in the water body to Fe2+, and the iron shavings themselves are oxidized to Fe2+, thereby maintaining the activity of the denitrification water body.

C. Desulfurization:

S02 is soluble in water, so the single-layer denitrification water filter bed inherently has the function of absorbing S02. The waste iron filings added to the water body not only replenish Fe2+ in the water but also, when the elemental iron reacts with H2S03, it can solidify and absorb S02, thereby initially reducing the S02 content in flue gas. Subsequently, the flue gas enters the second-layer water filter bed, where it undergoes flue gas desulfurization using the sodium-calcium double alkali process. The main desulfurizing agent in the water body is NaOH, with an external regeneration pool using quicklime as the regenerating agent for NaOH. The flue gas undergoes thorough "gas-liquid" impact desulfurization reactions in the second-layer water filter bed, complemented by the use of a pump to extract water from the external regeneration pool for intercepting and spraying to enhance desulfurization, resulting in a high desulfurization efficiency.

D. Dehumidification and defogging

Fine particles and N0x, S0 residues are further washed and purified in a secondary water-filtered water bed, and then, in the desulfurization仓at the top, the gas is treated and purified through a three-phase separator before being discharged.