Last August, an underwater volcanic eruption near Japan released vast amounts of pumice rock into the sea. These tiny lightweight rocks have since made their way to the Taiwan, posing a threat to local wildlife and ship engines. But as the saying goes, necessity is the mother of invention. In New Taipei’s Wanli District, one man has built a simple machine that can quickly filter pumice from the ocean. Let’s see how it works. ##

A triangular structure floats on the surface. Inside, a machine pumps water from the structure into a pipe.

The water contains lots of pumice fragments. They are filtered through a net, to catch even the small pieces.

Wang Kuo-chang
Inventor
The main machine is underwater. It works like a siphon, sucking up the pumice into our pipes.

This device was developed by diving instructor Wang Kuo-chang. It uses a vacuum to draw water carrying small pieces of volcanic rock. It took half a month of testing before it was able to operate 24 hours a day.

Chen Chi-fang
Fisheries Agency
The machine saves a lot of work and time. It’s automated and effective. It’s also worth looking into putting more of them in fishing ports everywhere. And if more pumice suddenly floats into a port, we can rent one for a day or two to clean out the pumice.

Last August, an underwater volcanic eruption near Japan released pumice into the ocean. The pumice has been floating to Taiwan, threatening marine wildlife and fishing vessels. Small stones have gotten lodged in ship engines and broken down cooling systems. It’s dangerous and the repairs are expensive.

Hsiang Yen-hao
Boatman
They can ruin the whole engine, and in severe cases, it can cost the owner millions. For example, ours is lighter, so if you take it apart to wash it, it might cost you tens of thousands of NT to clear it out.

Wang Kuo-chang
Inventor
Here in Wanli, every day we have to – look, there are so many people scooping the rocks out. It’s high tide so we can do that now. But in low tide we can’t do anything. We don’t have enough manpower. There’s so much and it’s heavy.

Before, fishermen used skimming nets to clear out the floating stones. Now, thanks to the machine, they no longer need to work so hard, saving time and energy. The machine’s developers have provided design blueprints free of charge, to support mass production and to help more fishermen clean out their ports.