Khawa Ijen: The Electric Blue Beauty

Nature has its own way to astonish us. Sometimes, in the forms of blooms, sometimes in the form of volcanoes. Now, when we hear volcane, the first picture that comes to our mind must be of red, hot and viscous lava, flowing down the edges of the volcano. But that image is going to change soon, hopefully. And the credit goes to the Ijen, a volcano complex in Indonesia.

The Blue Beauty

Indonesia, apart from being the country with the largest number of volcanoes, also houses a natural uniquiety, Kawah Ijen volcano. Part of the Ijen volcano complex, situated in East Java, Indonesia, this volcano is famous for two things: a mass of electric blue liquid flowing down the sides of the volcano and the lake situated in its crater. Also known as the Kawah Ijen Crater lake, this lake has the status of being the largest highly acidic crater lake. The acidity of the water can be as high as 0.5  at the edges and 0.13  in the middle, in terms of pH. Due to the high levels of acidity, the water of this lake maintains a turquoise shade. This lake also happens to be the origin source of the river Banyupahit, which obviously, also has a high concentration of acidic compounds and metals. 

The reason behind the high acidity of the lake is that the water is saturated with hydrochloric acid. The source of this hydrochloric acid is the hydrogen chloride gas emitted by the volcano. The hydrogen chloride gas, when reacts with the water, gives rise to hydrochloric acid, with pH upt almost 0. The acidity sometimes imparts a slightly strong green colour to the water sometimes.

The reason for this electric blue wonder, though, is just pure, simple chemistry. Between sulphur and oxygen. Sulphuric gas, originating under high pressure and temperature (600°C) conditions, emerge through cracks and vents in the volcano structure. Coming in contact with the atmosphere (360°C), specifically oxygen, triggers the sulphur to combust, in the process, shooting flames at a height upto 5 metres (16 feet). 

When the gases condense into liquid sulfur, while burning, this liquid flows down the volcano slopes, along with the sulfur rich lava, giving the ultimate spectacle of blue flames. Infact, this phenomenon is also known as the Api Biru (Blue Fire) amongst the locals.

Needless to say, there is a vast expanse of sulfur in this volcanic structure. And as a part of the industrial development, this treasure mine of a resource has also been tapped. Naturally, the burning gases, on gradual condensation, deposit sulphur around the lakes. To speed up the production of sulphur, a mining company has devised their own system to aid the condensation. They have installed ceramic pipes on an active vent near the edge of the lake, which condenses and liquefies the sulfur gases passing through them. To assist this process, miners often spray cold water over the pipes. This liquid sulfur is diverted through the vent slopes to get deposited onto the sulfur mats, where they solidify. 

The miners cut these sulfur into manageable pieces and take them down the mountains on their back. They are known to carry loads of around 80 to 100 kilograms once everyday, or twice, if they work through the night. Apart from that, they also collect sulphur stalactites, which sometimes form from the dripping sulphur drops, to sell to the tourists. And for the elemental chunks of sulphur, they get about 680 Indonesian rupiah (about 6 USD cents) per kilo. 

The Darker Side 

The working conditions are far from ideal. Not only have they been exposed to highly toxic volcanic ashes and gases, more so due to the lack of protection, but also are at risk due to the dangerous trek they need to do to reach the carter. Many miners suffer from chronic and severe health problems due to the inhalation of the toxic sulfuric air, over a long period of time. Several media houses and individuals have made documentaries and pieces regarding the plight of these local sulfur miners.

Speaking of the tourists, this incredible phenomenon got its due attention when National Geography mentioned about this place. Since then, Ijen has witnessed a surge of tourists, whose most preferred activity is a night time, two hour hike to enjoy the electric blue flames in the fullest glory. But certainly not without precautionary measures!

Website Reference:

https://www.nationalgeographic.com/news/2014/1/140130-kawah-ijen-blue-flame-volcanoes-sulfur-indonesia-pictures/

https://en.wikipedia.org/wiki/Ijen

https://interestingengineering.com/blue-lava-largest-sulfuric-acid-lake-ijen-volcano

Image Credit: Reddit