Hydrogen Sulfide Project Detailed Information

PROBLEM:

The problem consists of multiple variables that can affect my actions towards solving. Therefore, I have contacted some of the professionals in this field. With some advanced terminologies, I grasped the concept firmly.
Speaking of the findings, I narrowed down my target substance from toxic to hydrogen sulfide  because the harm it gives to the environment has made it the perfect focus area. Then, I made a research about how hydrogen sulfide occurs in the pipes and what gives its toxicity. More deeply, I realized the correlation between lack of oxygen and hydrogen sulfide. 
By the same token, in anaerobic conditions, sulfate is converted to sulfur ion by the bacteria as an oxygen source for biochemical reactions. Later, the sulfur ion also reacts with hydrogen to form hydrogen sulfide. Moreover, being a dangerous gas, hydrogen sulfide is heavier than the air by %20 which leads it to sediment under the sewage pipes. Which in turn, gives the water’s construction toxicity. On top of that, this toxic wastewater can erode the sewer pipes and mix with the soil, or it can damage the aquatic ecosystem from the sewer pipes opening to the water resources.
However, some recent methods for solving this obstacle are available in newly constructed sewage systems, which are not usable for the majority. What is more, a system named “Aeration Mixers ” is one of the conventional systems to reduce the oxygen inefficiency problem. In this system, the diffuser plays a vital role in the oxygen reaching the bacteria. This effective installation equipment increases the oxygen solubility in water to a very high level. Nevertheless, there is quite a fraud this system accommodates within, t external hydrogen sulfide may get out the diffusers when the capacity level reaches out. Additionally, this system is set up for the recently constructed sewage pipes. For example, armed with the discussions I have had with DİSKİ authorities, Diyarbakir is possessed of widely used wastewater plants that go back to the 90s which has a negative influence on its availability. Also, I would like to point out the fact that %92 percent of the sewer systems in the world have been implemented in the last 15 years or older. The comprehension I have gained with the help of my research, in this case, I might conclude that the low accessibility of this system creates a need for a new alternative system which I am planning to design.

PROJECT AND PROTOTYPE: 
Having known the massive impact of oxygen level on the hydrogen sulfide level relatively, I mainly focused on the ways for the oxygen to get into the pipes. I realized something vital for the last shape of my solution project. There was no need for oxygen to come from outside, it can be produced within the sewage pipes. Moreover, I deduced to use the algae, cyanobacteria for oxygen production. As a general knowledge, these prokaryotic beings are being held responsible for the creation of %80 oxygen on the Earth. However, there was a little flaw in my thinking, light energy. As most of the kinds are photosynthetic, they would be needing an energy source to perform their oxygen production process. Before mentioning how I catered this feature, I want to present my whole prototype manufacturing phase. 
First of all, I thought of the outer skeleton of the prototype as being a rectangular prism for better compatibility and easier mass production. Then, I placed two chambers inside the prism for the hydrogen sulfide detector I used in my project and for the algae also known as cyanobacteria. These spaces are identically the same but placed in exactly opposite positions on the rectangular prism. Moreover, one of them is completely open at the bottom, so there is a hole in the form of space from top to bottom for holding the algae with a mechanism that opens and closes. The other chamber was designed to hold the detector close to the mechanism for eliminating accuracies. Mentioning the electrical system, I utilized an Arduino System in which I included an Arduino Uno Card, a breadboard, a DC motor, a sound sensor, several jumper cables, and lastly some resistance for the wiring.
So let’s talk about the working principle, firstly, as the hydrogen sulfide gas detector is known for vibrating and sounding when detecting the target substance in a certain threshold level which can range from 1 to 15 ppm depending on the device’s capacity. The sound sensor recognizes the treble and sends the command to the Uno Card to activate the DC motor. This sensor was coded for detecting only the trebles. If I arranged it to the general sounds like water floating, the hatch located under the algae chamber would stay open forever. In the hatch I designed, I use a DC motor in order to open and close it.
Later, as I was aware of the light need of algae, I added an extension for holding an Arduino light bulb. This way, I was able to provide a suitable environment for photosynthetic cyanobacteria. Having all that done, I finally completed my prototype production.