Chapter 378—Oxygen and Nitrogen
This test is not only of great practical significance, but also an excellent educational opportunity, so in addition to participants Ai Gesha, Sylvie, Chamez In addition to Camo Spoel, Roland also called the other members of the Witch Alliance, Carter, Axe and Barov. In order to accommodate these 20 people, the test site was selected in the fifth experiment with the largest space. room.
For the first time, the fractionation vessel was not made too large, about one person tall, one meter in diameter, similar to a tower. The inside of the container is divided into three layers, the bottom layer is air intake, and the upper two layers are used for exhausting.
Before the separation began, Roland first gave everyone a simple chemistry class, told them what might happen, and put a few small questions, let Everyone is looking for an answer by themselves - in addition to being able to attract the interest of the audience, it can greatly enhance the effectiveness of teaching, which is also the skill used by chemistry teachers.
"...In theory, when Aegusa lowers the internal temperature of the container, the air gradually condenses into a liquid, which passes through the perforated partition and drops to the bottom. So when you observe that there is fluid at the bottom, tell us."
Because it cannot be directly visualized, it must be observed by Hilli through the container, it will change Described, so Roland is particularly detailed in this section.
Silvi nodded in doubt, "Can you really see the liquid? Is it not the water vapor in the jar?"
"Reassure, the liquid air is light blue, completely different from water vapor." Roland waved. "And at that temperature, the water vapor has solidified into ice crystals." Then he made a love for Gesha. A gesture, "Let's get started."
"Wait... this hole at the bottom of the container doesn't need to be blocked?" she asked.
"There will be some more blocking, otherwise the air in the jar is too small, and no obvious change is observed." Because it was only a test, Roland chose the easiest The way to inhale - when the temperature inside the tank drops rapidly, the pressure will drop, causing the outside air to constantly flow into the tank. In normal production, this is not worth the loss, because the air-conditioning will continue to be lost, wasting energy, but Ai Gesha uses magic, and the cooling efficiency is far more than any refrigerator, so Roland is too lazy to prepare the air pump to inflate.
Ai Gesha took a deep breath and pressed her hands on the fractionation tower.
Between the number of interest, there is a howling sound in the intake pipe, which is the sound of the rapid influx of airflow. A layer of hoarfrost emerges at a rate visible to the naked eye around the nozzle and is constantly expanding - the moisture in the air quickly condenses at the low temperature of the overflow and adheres to the outer wall of the container. Anna turned the black fire into a thread and cleaned up the ever-increasing ice crystals.
In a short while, Sylvie said with surprise, "I saw liquid on the partition, but more white cream."
"White condensate may be influx of water vapor, or it may be crystalline carbon dioxide," Roland explained. "Considering the extremely low carbon dioxide content in the air, most It should be water vapor.”
If the air is drawn into the fractionation tower before it is officially produced, it must be dried first, otherwise the water vapor will easily block the layer after condensation. Plates and vents reduce production efficiency.
After about a quarter of an hour, Sylvie reported that the bottom of the container had been filled with blue liquid, and Roland let Soroya block the intake pipe and coat it. seal.
The next step is the key warming.
Depending on the boiling point of nitrogen and oxygen, nitrogen will first reach the boiling point, and the gas will escape upwards, thereby achieving separation. At this temperature, he does not remember the specific value. At present, there is no means to measure it. It can only be grasped by Ai Gesha himself. The specific performance is that the vent hole at the top of the fractionation column has gas discharge, and the remaining liquid at the bottom will become bluer, which means that the purity of liquid oxygen is continuously increasing.
Fortunately, Ai Gesha is no stranger to the control of magic. She accurately adjusts the cooling rate and makes it slowly rise. In a short while, Sylvie also observed. Liquid level boiling phenomenon. Bubbles began to appear in the coated tubes that passed into the water, and Kaimo quickly collected several bottles of gas using the drainage gas collection method.