Publication: Stormwater quality improvement by a porous pavement
| dc.contributor.author | Makhtar, Salwa Mohd Zaini | |
| dc.date.accessioned | 2024-01-12T07:34:55Z | |
| dc.date.available | 2024-01-12T07:34:55Z | |
| dc.date.issued | 2020-05-01 | |
| dc.description.abstract | Increasing quantity and decreasing quality of stormwater runoff is natural but problematic consequences of urbanization. In addressing the issue, the porous pavement usage with modular installation system has been the new alternative being experimented instead of the traditional impervious asphalt and concrete pavers. It allows for reduction in surface runoff quantity while lowering the concentration of hazardous stormwater pollutants, including the heavy metals, in the infiltrate. The effectiveness of porous pavement in eliminating dangerous pollutants depends upon the media materials used which are expected to capture most of the heavy metals. This research examined the potentials of an invented surface fill arrangement to be used in conjunction with the hexagonal modular system where the media tested consists of granular activated carbon (GAC), sand and zeolite. The three paver materials were of uniform gradations, respectively with hydraulic conductivity values of 0.052 cm/s, 0.064 cm/s and 0.068 cm/s, which can be considered as medium ranged. The batch study was carried out to determine the adsorption capacity of each medium in reducing the heavy metal impacts of lead (Pb), copper (Cu), cadmium (Cd) and zinc (Zn) in the influent. The adsorption isotherms of GAC, sand and zeolite towards Pb, Cu, Cd and Zn was found to follow the Langmuir model, the Langmuir adsorption capacities were noticed respecting the order of Pb > Cu > Cd > Zn, while the adsorption kinetics on all of the paver materials obeyed the Pseudo-Second Order model. Next, the Mixture Simplex Lattice Design was used in the column study to determine the optimized usage of the media in removing the heavy metals. The resulting optimum bed heights of 5 cm, 5 cm and 0 cm respectively for the GAC, sand and zeolite, corroborated with the outcome of employing the optimization function, thus validating the reliability of the given arrangement. The column study also gave percentage removals of 99 %, 88 %, 98 % 84 % for the Pb, Cu, Cd and Zn respectively. The concern for loss of efficiency due to clogging was addressed by tests carried out on a hexagonal modular unit with 5 cm thick GAC positioned at the top, followed by 5 cm thick sand at the bottom. Generally, the clogging agent was found trapped only on the mesh because of the sizes of some of the material being larger than the size of mesh opening, while the voids of the media material were found to be not of a major effect in this respect. With the GAC and sand layers combined, the hydraulic conductivity was determined to be 0.097 cm/s and this k value can be considered low for the purpose. Modelling using CFD ANSYS FLUENT software and visualizing the changes in the hexagonal module filled with GAC and sand of 5 cm thickness each resulted in a flow velocity of 3.5 x 10-5 m/s while a physical experiment on the fixed filter bed media consisting of the two materials gave an unsaturated velocity of 3.08 x 10-5 m/s. The 12 % difference between the experimental and simulated velocities was considered acceptable. The results showed that GAC and sand can be used as the media for the modular paver system that treats stormwater for heavy metals contamination while serving as a practical porous pavement alternative. | |
| dc.identifier.uri | https://erepo.usm.my/handle/123456789/18060 | |
| dc.language.iso | en | |
| dc.title | Stormwater quality improvement by a porous pavement | |
| dc.type | Resource Types::text::thesis | |
| dspace.entity.type | Publication | |
| oairecerif.author.affiliation | Universiti Sains Malaysia |