Tag Archives: Hydrogen

Things You Should Know About the Uses of Hydrogen

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Hydrogen will be one of the critical assets in the energy stream in the coming decades for the sustainable development of society. The abundant availability of hydrogen and its application in electricity production using fuel cells without any harmful emissions makes it distinct. It can be produced from renewable and sustainable resources, thus promising an eco-friendly solution for the energy transition in the coming years.

Currently, hydrogen production using the electrolysis of water is most preferred. However, hydrogen production can vary in the range of sectors. Hydrogen can be used in electricity production, biomass, solar and wind power application.

applications of hydrogen gas

Despite its advantages, two significant issues hinder its commercialisation and generalisation as an efficient fuel, and energy transition toward zero-emission and fossil-free energy solutions. The first is hydrogen is an energy vector, which means hydrogen needs to be produced before its use and eventually lead to energy consumption in hydrogen synthesis. The second is the low volumetric energy density of hydrogen, which leads to hydrogen storage and transportation issues because of its lowest volumetric energy density (0.01079 MJ/L)

Researchers have suggested several solutions to attempt to increase this value:

  • compression in gas cylinders;
  • liquefaction in cryogenic tanks;
  • storage in metal-hydride alloys;
  • adsorption onto large specific surface area-materials
  • chemical storage in covalent and ionic compounds (viz. formic acid, borohydride, ammonia)

Applications of Hydrogen

The hydrogen applications are in the food industry to turn unsaturated fats and oils present in vegetable oils, butter into a saturated state. In the metal forming industry, atomic hydrogen welding is used as an environmentally sustainable welding process. In the manufacturing industry, hydrogen and nitrogen are used to create a boundary and prevent the oxidation of metals.

The recent advancements in hydrogen applications in the steel manufacturing industry are one of the most significant hydrogen applications for low or zero-emission iron ore conversion.

ecofriendly-manufacturing

The potential use of hydrogen can play a vital role in reducing greenhouse emissions and the global target of achieving a minimal no emission target by 2050. However, the automotive industry is still the largest consumer and most attractive sector in the current scenario. But with the future forecast of reducing hydrogen fuel cost can do wonders with the goal set during Paris Climate Summit.

Hydrogen use in stationary and automotive applications, such as fuel cell vehicles and hydrogen refuelling stations above all, has shown to be hindered by its volumetric energy density – the lowest among all the standard fuels nowadays used. Compression seems to be the most efficient solution to reach high storage levels, thus making hydrogen more common as a renewable and sustainable fuel.

uses of hydrogen

The availability of several hydrogen compression technologies makes the development of new innovative and environmentally-friendly solutions for the use of energy possible, leading to a transition towards a fossil fuel divestment and making a critical contribution to sustainable development

Biomass Gasification Power Systems

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Biomass gasification power systems have followed two divergent pathways, which are a function of the scale of operations. At sizes much less than 1MW, the preferred technology combination today is a moving bed gasifier and ICE combination, while at scales much larger than 10 MW, the combination is of a fluidized bed gasifier and a gas turbine.

biomass-gasifier

Larger scale units than 25 MW would justify the use of a combined cycle, as is the practice with natural gas-fired gas turbine stations. In the future it is anticipated that extremely efficient gasification based power systems would be based on a combined cycle that incorporates a fuel cell, gas turbine  and possibly a Rankine bottoming cycle.

Integrated Gasification Combined Cycle

The most attractive means of utilising a biomass gasifier for power generation is to integrate the gasification process into a gas turbine combined cycle power plant. This will normally require a gasifier capable of producing a gas with heat content close to 19 MJ/Nm3. A close integration of the two parts of the plant can lead to significant efficiency gains.

The syngas from the gasifier must first be cleaned to remove impurities such as alkali metals that might damage the gas turbine. The clean gas is fed into the combustor of the gas turbine where it is burned, generating a flow of hot gas which drives the turbine, generating electricity.

Hot exhaust gases from the turbine are then utilised to generate steam in a heat recovery steam generator. The steam drives a steam turbine, producing more power. Low grade waste heat from the steam generator exhaust can be used within the plant, to dry the biomass fuel before it is fed into the gasifier or to preheat the fuel before entry into the gasifier reactor vessel.

Schematic of integrated biomass gasification combined cycle

The gas-fired combined cycle power plant has become one of the most popular configurations for power generation in regions of the world where natural gas is available. The integration of a combined cycle power plant with a coal gasifier is now considered a potentially attractive means of burning coal cleanly in the future.

Biomass Fuel Cell Power Plant

Another potential use for the combustible gas from a biomass gasification plant is as fuel for a fuel cell power plant. Modern high temperature fuel cells are capable of operating with hydrogen, methane and carbon monoxide. Thus product gas from a biomass gasifier could become a suitable fuel.

As with the integrated biomass gasification combined cycle plant, a fuel cell plant would offer high efficiency. A future high temperature fuel cell burning biomass might be able to achieve greater than 50% efficiency.