Miftahul Nadya

PROGRESS I : CASE STUDY OF HYDROGEN STORAGE OPTIMIZATION PROJECT

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Hydrogen storage refers to the process or technology used to store hydrogen in a safe and efficient form until it is used or consumed.

Hydrogen is a highly reactive and flammable chemical element, so its storage must pay attention to safety and take into account the special characteristics of hydrogen.

The size of the tank needed to store 1 liter (1 L) of hydrogen will depend on the storage conditions, i.e. whether the hydrogen is stored in gaseous or liquid form.

Here are some approximate tank sizes for storing 1 L of hydrogen:

- Gas Storage: To store 1 L of hydrogen in gaseous form, the tank required will depend on the desired pressure and storage temperature. This requires storage tanks to have pressures of 350-700 bar or 5000-10,000 psi. Under these conditions, commonly used tank sizes range from a few liters to tens of liters, depending on the tank design and material.

- Liquid Storage: When hydrogen is stored in liquid form at low temperatures (about -253°C), its volume is significantly smaller than when it is in the gaseous state. However, to store 1 L of liquid hydrogen, a sophisticated and well-insulated storage system is required, such as a dewar tank specially designed to store liquid hydrogen.

- Absorbent Materials: Some materials, such as metals or imported solids (such as metal hydrides), can absorb significant amounts of hydrogen. Hydrogen can be absorbed by this material and released when needed.

There are several materials that can be used to make hydrogen storage tanks.

Some of the materials commonly used include:

- Steel: Steel is a material that is often used in the manufacture of hydrogen storage tanks. Stainless steels such as nickel alloy steel are common choices because of their high strength and corrosion resistance.

- Carbon fiber composites: Carbon fiber composites, especially carbon fiber reinforced with polymer resins, are used in the construction of high pressure hydrogen storage tanks. Carbon fiber composites have high strength and light weight, making them suitable for use in applications where weight is an important factor.

- Aluminum: Aluminum can also be used in the manufacture of hydrogen storage tanks. Aluminum has a low density and can withstand hydrogen pressure well. However, aluminum is susceptible to corrosion by hydrogen, so proper protection is necessary to prevent damage.

- Hydrogen resistant polymers: Hydrogen resistant polymers such as polyether-ether-ketone (PEEK) and polyether-sulphone (PES) are also used in some hydrogen storage applications. This polymer has good mechanical strength and resistance to hydrogen.

The size of a hydrogen storage tank will depend on many factors, including pressure, temperature, type of hydrogen (gas or liquid), and specific application requirements.

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PROGRESS II : OPTIMIZATION OF HYDROGEN STORAGE DESAIGN

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One way to store hydrogen is as gasoline, with the additional advantage that carbon is stored along with the hydrogen, both being good sources of energy.

The two downsides of gasoline are

(i) when used to power heat engines its efficiency is in the range 20–30% (a fundamental limitation of the Carnot and Otto cycles), and

(ii) although the H2O emitted by burning hydrogen is good for the planet, the CO2 emitted by burning carbon causes global warming.

Hydrogen stored at 70 MPa (700 atmospheres) as in all passenger fuel cell vehicles today has various downsides including

(i) the high cost of compressing it and then refrigerating it to -50 °C to permit fast fill, and

(ii) the insanely high factor of 15 in tank weight to contents weight.

At 70 MPa the density of H2 is about half that of liquid hydrogen at 0.06 g/cc. Neither compression nor liquefaction is as effective as chemistry in pulling hydrogen atoms together as in gasoline. The question then arises as to what chemical solutions besides those like gasoline that contain carbon exist. Ordinary compressed gas cylinders suffice for a large number of regular applications like welding and small scale semiconductor R&D applications.

Material of Storage

Tank made from carbon fiber with a metal liner (Aluminium or steel).

Let's see metal matrix composite. Approximate maximum pressure, aluminium/carbon 700 bars (70 MPa; 10,000 psi).

Dimensions of the storage cylinder

V = πr^2 x h

Where,

V = Volume/Capasity = 1 L = 1000 dm^3

π = 3,14

r = radius (dm)

h = height (dm)

1000 = π x 5^2 x h (Assumption D = 10 dm)

1000/(π x 25) = h

h = 12.73 = 13 dm

Hydrogen Storage Design

Link Google Drive : usp=sharing[1]