The Power of Reversible Hydrogen Fuel Cells: Separating Hydrogen and Oxygen from Water

Introduction:

The quest for clean and sustainable energy sources has led to significant advancements in the field of hydrogen fuel cells. One of the key challenges in harnessing hydrogen as an energy carrier is the separation of hydrogen and oxygen gases from water. In recent years, reversible hydrogen fuel cells have emerged as a promising solution for this task. In this article, we will explore the workings of reversible hydrogen fuel cells and their role in efficiently extracting hydrogen and oxygen from water.

 

Understanding Reversible Hydrogen Fuel Cells:

 

Reversible hydrogen fuel cells, also known as reversible proton exchange membrane fuel cells (PEMFCs), are a variant of traditional PEMFCs. While conventional PEMFCs generate electricity from hydrogen gas, reversible fuel cells can operate in reverse mode, enabling the production of hydrogen and oxygen gases from water.

 

Mechanism of Action:

 

Reversible hydrogen fuel cells operate through a series of electrochemical reactions that take place within the cell. Let's dive into the detailed process:

1. Electrolysis Mode:

In the electrolysis mode, an external electrical current is supplied to the reversible fuel cell, initiating the splitting of water molecules into hydrogen and oxygen gases.

• At the anode:

2H2O (liquid) → 4H+ (protons) + 4e- (electrons) + O2 (oxygen gas)

• At the cathode:

4H+ (protons) + 4e- (electrons) → 2H2 (hydrogen gas)

 

When the electrical current is applied, water molecules at the anode are oxidized, releasing protons (H+) and electrons (e-). The protons migrate through a proton exchange membrane to the cathode, while the electrons flow through an external circuit. At the cathode, the protons and electrons combine, resulting in the production of hydrogen gas.

2. Fuel Cell Mode:

 

During the fuel cell mode, hydrogen gas and oxygen gas are supplied to the reversible fuel cell, which then generates electrical energy through the reverse reaction.

• At the anode:

2H2 (hydrogen gas) → 4H+ (protons) + 4e- (electrons)

• At the cathode:

O2 (oxygen gas) + 4H+ (protons) + 4e- (electrons) → 2H2O (liquid)

 

In this mode, hydrogen gas is oxidized at the anode, releasing protons and electrons. The protons migrate through the proton exchange membrane to the cathode, while the electrons flow through an external circuit, generating electrical power. At the cathode, oxygen gas combines with protons and electrons to form water.

Note: This animation from FREUDENBERG Youtube Channel will remove your confusion about Electrons migration and producing Electricity.

Efficiency and Advantages:

 

Reversible hydrogen fuel cells offer several advantages over traditional electrolysis methods for hydrogen production. Firstly, they are highly efficient, allowing for the conversion of electrical energy into chemical energy (hydrogen) with minimal energy loss. Secondly, these fuel cells can be integrated with renewable energy sources, such as solar or wind power, enabling sustainable hydrogen production. Furthermore, reversible fuel cells provide the flexibility to switch between electrolysis and fuel cell modes, making them versatile for various applications.

 

Conclusion:

 

Reversible hydrogen fuel cells represent a significant leap forward in the field of hydrogen separation from water. By leveraging the principles of electrochemistry, these innovative cells enable the efficient extraction of hydrogen and oxygen gases. With their high efficiency and adaptability, reversible fuel cells hold great potential for a sustainable and clean energy future, providing an eco-friendly alternative to traditional fossil fuel-based systems.

 

Once again, many thanks from ELBCAMPUS administration for providing us such an interesting subject with great practical methods.

 

Naeem Nekmal

Hamburg, Deutschland

June, 2023

How to Determine Your Well Pump Flow Rate on Wells with Pressure Tanks

An overview: The first step is to count the gallons “drawn down” from the pressure tank. This is the amount of water the pressure tank stores before your well pump needs to kick in. This is known as pressure tank ‘drawdown’.

Then the next step is to time (in seconds) how long it takes for your well pump to turn on and then turn off. This is referred to as the cut-in and cut-off cycle of the well pump.

You just need those two numbers: The amount of water in gallons, of the drawdown of the pressure tank; and the time in seconds it takes for the well pump to fill up an empty pressure tank!

Here are the Easy Steps To Take:

First, allow the well pump to build up to full pressure by running water in the home or from a hose bib or faucet until you hear the well pump kick in or pressure switch points click.

Close faucet and make sure no water is being used in the home. Well pump will build up pressure for a few minutes and then pressure switch will shut off well pump.

Next, open a hose bib (also referred to as a ‘spigot’ or ‘faucet’) anywhere near or after the pressure tank.

Run the water into a 5-gallon bucket, noting how many gallons you collect. If bucket fills up, dump out water and keep measuring and filling.

Measure the number of gallons drawn down from the pressure tank until the well pump turns on.

When you hear the pump turn on, immediately close the hose bib.

Time the period in seconds it takes for the well pump to build back up to pressure that is, between the cut- in and cut- out of the pressure switch. The pressure switch turns on the pump at a lower pressure and turns off the pump when it reaches a higher pressure.

The formula for determining the flow rate is gallons drawn down (that were measured above), divided by the seconds required for recovery, then multiplied by 60:

(Gallons / Seconds) x 60 = Gallons per Minute (GPM) flow rate..

For example, if 20 gallons are drawn down and it takes 120 seconds to build pressure back up, then: 20 divided by 120 = .166. Then multiply .166 x 60 = 10 gallons per minute flow rate.

So you have a 10 GPM flow rate.

Mechanization in Construction Industry- Motivations, and Advantages

Mechanization is the process of shifting from working largely or exclusively by hand to do that work using machines. The construction projects are becoming more demanding and complicated in construction and delay of projects would arise if the conventional construction method is used.

Delays in construction are costly and have prompted developers to embrace mechanization. Construction machinery is used in order to achieve larger output, cost-effective, execution of work that is not feasible by manual efforts, reduce the amount of heavy manual work which would cause fatigue, maintaining large output, and finalize projects on time.

Mechanization is based on rented construction equipment is cost-effective. construction equipment when rented can be exactly to match the requirement. For rented equipment, time to make the equipment ready for operation is important.

Motivations for Mechanization of Construction Industry

• The work can be done speedily which avoids the time and cost over-runs.
• A large number of materials can be handled, so the size of the project can be increased
• The complex projects involving high-grade material.
• High-quality standards can be maintained.
• A time schedule can be kept.
• Optimum use of material, manpower, and finance.
• Shortage of skilled and efficient manpower.
• To control the duration and cost implications by using mechanized equipment over the Conventional method, which can be used in the planning of construction projects.
• Lower insurance costs for builders.
• Easier and safer work for construction workers.
• Increased sustainability over a building’s lifetime.
• Little to no building-site construction waste.

Applications of Construction Mechanization

1. Highway projects
2. Irrigation
3. Buildings
4. Power plant and other applications

Fig. 1: Highway Construction

Fig. 2: Mechanization of Building Construction

Sources of Construction Mechanization

Fig. 1 illustrate the source of equipment from which construction equipment can be selected and obtained.

Fig. 3: Sources of Equipment

Factors Affecting Selection of Construction Equipment

1. Availability of equipment.
2. Suitability of job condition with special reference to climatic and operating condition.
3. Uniformity type; easier operation and maintenance, easy exchange of spare parts and operating personnel.
4. Size of equipment.
5. Use of standard equipment; made by several companies so that easy purchase and delivery.
6. Country of origin; If importing foreign exchange facilities should be easily available.
7. The unit cost of production – the cost of running.
8. Availability of spare parts and selection of manufacturers.
9. Availability of local labor for operations.
10. Function to be performed.
11. The capacity of the equipment.
12. Method of operation and its limitations.

Common Types of Construction Equipment

• Earthmoving equipment
• Hauling equipment
• Hoisting equipment
• Conveying equipment
• Aggregate and concrete production equipment
• Pile driving equipment
• Tunneling and rock drilling equipment
• Pumping and dewatering equipment
• Tower cranes
• Laser Screeding Paving machine
• Plastering machine
• Bar cutting machine
• Bar straightening
• Core drill machine
• Laser screed Machine
• Arial platform work lifting machine

Fig. 4: Tunnel Construction Machine

Fig. 5: Laser Screed Machine

Advantages of Construction Mechanization
Economical
Improve construction quality
Increase the safety of construction conditions
Enhance the speed of construction
Feasibility
Disadvantages of Construction Mechanization

1. Loss of Skill

The craftsman with the superior skill had disappeared. Such skill is no longer necessary. The only type of skill that is needed now is to run the machines.

2. Dependence

Machinery has increased our dependence on others. We depend on our water and light on the satisfactory working of water-works and the power-house.

A small flaw would result in the supply of these necessaries being cut off at any time. This may mean not only an inconvenience but a serious dislocation of normal life.

3. Insanitary Surroundings

Big factories pollute their surroundings and make them filthy and unsanitary. This has led to moral degradation and physical deterioration.

4. Over-specialization

Machinery leads to too much specialization. This overspecialization increases the risk of unemployment and cramps the worker physically.

5. Class-conflict

The use of machinery is responsible for class-conflict—the capitalist on one side and the laborer on the other.

6. Unemployment

It creates unemployment because one machine can take the place of several men.