electric arc furnace

Examples of electric arc furnace in the following topics:

• Steelmaking and Refining

  • Secondary steelmaking is most commonly performed in an electric arc furnace.
  • Once the furnace is charged with scrap metal, meltdown commences.
  • The electrodes are lowered onto the scrap, an arc is struck, and the electrodes are set to bore into the layer of shred at the top of the furnace.
  • Once the electrodes have reached the heavy melt at the base of the furnace and the arcs are shielded by the scrap, the voltage is increased and the electrodes raised slightly, increasing the power to the melt.
  • For plain-carbon steel furnaces, as soon as slag is detected during tapping, the furnace is rapidly tilted back towards the deslagging side, minimizing slag carryover into the ladle.

• One more time...

  • One day after class, two attendees approached me to discuss a business idea that involved encasing inefficient furnaces and boilers in factories with low-grade technology that converted wasted heat into electricity.
  • Their research had concluded that the number of poorly designed and badly insulated furnaces and boilers around the world was staggering so the target market was huge.
  • I asked them how much the wasted energy was worth compared to the amount of electricity it generated – and at that moment they realized the fault in their idea.
  • Without question, the raw material (wasted fuel) was worth more than the envisioned end product (electricity).

• Advantages of fuel cells

  • Since fuel cells are smaller than coal-fired furnaces, less land is required to set them up as compared to traditional power plants.
  • Recent breakthroughs in fuel cell technology have produced electricity from carbon and bacterial enzymes, which eliminates the need for precious metals (such as platinum).

• Putting Chaku-Chaku into practice

  • Waste heat from furnaces and boilers, exhaust, compressors and hot-liquid blowdowns can be collected and used in other processes.
  • In the USA, for example, most power stations convert 34% of their fuel into electricity.
  • Denmark, on the other hand, converts 61% or more of its electrical-plant fuel into power by, in part, recapturing heat with efficient furnace design.
  • • Insulate boilers and furnaces with ceramic fibres or other super-efficient materials.
  • As one factory worker told me, ‘If you can't place your hand on the exterior wall of a furnace because it's too hot, you're burning money. '

• Additional suggestions for eliminating production waste

  • Waste heat from furnaces and boilers, exhaust, compressors and hot-liquid blowdowns can be collected and used in other processes.
  • In the USA, for example, most power stations convert 34% of their fuel into electricity.
  • Denmark, on the other hand, converts 61% or more of its electrical-plant fuel into power by, in part, recapturing heat with efficient furnace design.
  • • Insulate boilers and furnaces with ceramic fibres or other super-efficient materials.
  • As one factory worker told me, ‘If you can't place your hand on the exterior wall of a furnace because it's too hot, you're burning money. '

• Preparing for change

  • The solutions they came up with – on their own included identifying and fixing steam leaks, reducing electricity consumption, super-insulating industrial furnaces and introducing real-time monitoring (immediate feedback from mechanical processes).

• Bronze Age Advancements in Metallurgy

  • Certain metals, notably tin, lead and (at a higher temperature) copper, can be recovered from their ores by simply heating the rocks in a fire or blast furnace, a process known as smelting.
  • Two golden arcs along the sides, marking the angle between the solstices, were added later.
  • A final addition was another arc at the bottom surrounded with multiple strokes (of uncertain meaning, variously interpreted as a solar barge with numerous oars, as the Milky Way, or as a rainbow).

• How much waste is out there?

  • For example, a new electric motor purchased for $1,500 can cost as much as $13,000 a year to run and a typical 100 horsepower AC induction motor purchased for $5,000 can require $35,000-worth of electricity to operate annually (some motors actually consume more than the amount of their purchase price in electricity costs every week).
  • As much as 70% of the energy produced from burning coal is lost in the power plant due to poorly insulated and poorly designed furnaces.
  • From the amount of electricity that emerges from the plant, 10% is lost due to inefficiencies in the transmission lines.
  • All together, the amount of electricity motors consume totals around 40% of the world's electrical power or roughly 75% of all industrial electricity usage.
  • And since most electricity is derived from burning coal, an examination of the costs behind coal must be taken into account.

• Building efficiently

  • If concrete must be used, consider a mixture of 55% concrete and 45% slag (a waste product from blast furnaces) which saves energy and produces an alternative that is stronger than concrete alone.
  • When wiring a building, use the next higher size diameter of electrical wire than that recommended by building code requirements.
  • Thicker copper wire costs more, but because it reduces electrical resistance it costs less to operate.
  • For example, around 10,000 structures (called passive houses) without furnaces or air conditioners have been built in Germany, Sweden and Switzerland.
  • Wider, regional benefits include increased air quality, lower electricity demands (particularly in the summer), reductions in local air temperatures, and an improvement in the aesthetics of the area where the building is located.

• Reflexes and Diagnosis

  • Scientific use of the term "reflex" refers to a behavior that is mediated via the reflex arc; this does not apply to casual uses of the term "reflex".
  • While the reflexes above are stimulated mechanically, the term H-reflex refers to the analogous reflex stimulated electrically, and Tonic vibration reflex for those stimulated to vibration.