A Novel Structure Applied to the Permeable Brick Paving System and Its Decontamination Performance

摘要

To improve the pollutant removal efficiency of the permeable brick paving system, a novel structure applied to the base layer was introduced, and its decontamination performance was researched. Suspended solids (SS), chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), total nitrogen (TN), total phosphorus (TP) and heavy metals (Cu, Zn, and Pb) in the influent and effluent were measured, and the role and mechanism of the fillers inside the novel structure were discussed by changing the type and size of the fillers. The results showed that the removal efficiency of the system using the frame structure was slightly lower than that of the cement concrete block. The removal efficiency results using different particles and materials showed that (I) The permeable brick system filled with small-diameter gravel was more effective than a system filled with large-diameter gravel, and the graded gravel of 3-15cm exerted multiple filtering effects, owning the same effectiveness as the gravel with particles sizes of 3-5 cm. (II) The addition of zeolite and iron filings in the framework could effectively reduce NH4+-N and NO3--N, while the addition of fillers such as volcanic rocks rich in iron oxides improved the adsorption effect of COD. The study provides a new and more environmentally friendly alternative for the base layer of penneable brick paving system.