Drying Oxygen in Aerobic Digestion
Waste water needs to be treated before it can be released back into the environment. There are many different processes that are used to accomplish this. This article focuses on how aerobic digestion works and why drying oxygen with desiccants can be beneficial to you.
Aerobic digestion requires the use of bacteria to digest the sludge, which is the collective contaminate in a water supply. The key component to making this process work is oxygen and there are two reasons why.
One reason why oxygen is needed is because large volumes of bacteria used in this process quickly eat up all of the oxygen the bacteria need to live, so without oxygen the process would not work and all the bacteria would die.
The second reason again revolves around aerobic bacteria eating up all of the oxygen. This presents another problem when releasing waste water back into a river or stream. When all the bacteria is released back into a stream for example they end up taking all of the river’s oxygen, which makes it impossible for plants and fish that are dependent on the stream to survive. The added oxygen ensures that there is enough for the wildlife.
Aerobic digestion works by using either a PSA oxygen generator or a cryogenic compressor/oxygen generator to aerate oxygen into the bacteria and sludge mixture. Before oxygen can be added the digestion process moisture needs to be removed from the air. This is done by using either silica gel or activated alumina in an air dryer. Once the air has been dried the aerobic bacteria can remove the sludge.
Drying the oxygen with silica gel and activated alumina can increase the efficiency of a PSA unit or cryogenic compressor, and help purify the oxygen thus giving you a higher concentration of it to insert into the digestion process. More oxygen equals more bacteria, and more bacteria makes sludge go away faster.
The primary advantage of aerobic digestion is that the process is quick and produces a high quality result. The downside is it uses a lot of energy and the potential to kill the bacteria if you do not use enough energy. The restart process once the bacteria are killed is very time consuming, and the extra cost from using too much energy to run this operation requires skilled workers and constant supervision.
Purifying and drying oxygen can help to prevent this from happening.