Scientists from the Chinese Academy of Sciences (CAS) have developed a real-time, wireless monitoring system to detect ammonia leakages in ammonia-powered ships.
According to the groups led by professor Feng Liang from the Dalian Institute of Chemical Physics (DICP) and professor Xu Minyi from Dalian Maritime University, the new leakage monitor system is self-powered by ammonia and it includes a honeycomb triboelectric nanogenerator (TENG)-based power generation system, a carbon nanotube doped polypyrrole (CNTs-PPy)-based ammonia detection system, and a signal collecting and transmitting system (Bluetooth).
Liquid ammonia is a promising marine fuel in the shipping industry due to its zero carbon, safe storage, and high energy density.
It has an energy density of around 3kWh per litre that lies somewhere between hydrogen and LNG in terms of storage volume.
Although traditionally produced from hydrocarbons, it can also be produced from renewable, non-carbon sources such as wind or solar energy resulting in green ammonia and blue ammonia respectively.
The only drawback is that it is a common toxic gas that can cause irritation to the mucous membranes and respiratory system—something you’d want to avoid on long sea voyages.
The DICP and Dalian Maritime teams have now found a way to remedy this through their self-powered ammonia detection system.
One of the first goals for the scientists lay in improving the electronic conduction efficiency via the synergistic effect between the carbon nanotubes and conductive polymers. This enhanced its sensing performance at room temperature.
According to the scientists, the sensor exhibited good performance with a low detection limit, short response time (about 90 seconds), high selectivity, good stability, and low cost.
Moreover, by using Bluetooth, the CAS and Dalian team realized wireless transmission from the detection module to the computer terminal.
And thanks to the honeycomb structure TENG provided by Dalian Maritime team, the system can collect and covert the mechanical energy generated by the vibration of the ship’s engine into electrical energy to self-power itself.
The new system was put to test on an expedition ship; it worked smoothly in the low-level cabin of the ship with high temperature and high humidity, confirming its potential in practical applications.
Image and content: Wärtsilä/Li Yuan-Chinese Academy of Sciences
