The Special Region of Yogyakarta faces a waste management problem following the closure of the Piyungan Landfill (TPA). To address this issue, a team of UGM students has innovated to reduce plastic waste, used oil, and rice husk waste by creating bricks using these materials.
The student team, part of the Student Creativity Program in Entrepreneurship (PKMK), consists of Mohammad Ridwan from the Civil and Environmental Engineering program, Yohanes Mario Putra Bagus from the Physics Engineering program, Shafa Zahra Aulia from the Chemistry program, Ratri Dwiyanti from the Accounting program, and Rakha Faiq Muyassar from the Industrial Engineering program.
In his presentation to reporters on Monday (Jul. 8), Yohanes Mario Putra Bagus, commonly known as Mario, stated that their brick innovation originated from the problem of plastic waste, which is difficult for society to manage, mainly because it decomposes very slowly in nature.
“Our country is the second-largest contributor of plastic waste in the world, and this waste is hard to decompose, thus requiring proper handling,” said Mario.
Furthermore, the team specifically chose used oil as one of the wastes needing attention, as it has been primarily used only as a termite repellent. Meanwhile, rice husk ash is known to contain silica, which can improve the quality of bricks.
“We process these three materials to enhance the quality of the bricks we make,” said Mario.
Shafa Zahra Aulia added that rice husk ash contains more than 90 percent silica, which not only improves the durability of bricks to prevent cracking but also absorbs heavy metals from used oil.
“This silica compound can absorb heavy metals from the oil to keep it safe,” she explained.
Additionally, Rakha Faiq Muyassar mentioned that the bricks they produce can minimize the impact of earthquakes.
“The design is shaped with a lateral style to minimize earthquake damage and resist cracking and breaking,” he said.
Ratri Dwiyanti explained that this PKMK innovation also involves selling the product to the public. Before selling, they conducted in-depth research regarding the standard durability and strength of the bricks. Each brick is sold at 5,300 rupiahs, and they produce around 120 bricks daily.
“We sell each brick for 5,300 rupiahs, and we are currently promoting and selling them to property agents and building material stores,” she said.
Regarding the composition of the three materials for producing one brick, Mario mentioned they use a ratio of 1 part cement to 6 parts sand, with 25 percent cut plastic waste, 10 percent rice husk ash, and 1-3 percent used oil.
Author: Gusti Grehenson
Photographer: Firsto