HyperTherm: Development of a high-performance electric process gas heater as retrofit to thermal processing plants.

For eco­no­mic reasons, ther­mal pro­ces­sing plants have in the past been hea­ted direct­ly or indi­rect­ly with fos­sil fuels, pri­ma­ri­ly natu­ral gas. This pro­cess releases CO₂ and other cli­ma­te-dama­ging gases into the atmo­sphe­re. In view of the plan­ned 55% reduc­tion in green­house gas emis­si­ons by 2030 com­pared to 1990, the con­ver­si­on of such gas-fired heat tre­at­ment plants to alter­na­ti­ve hea­ting methods is unavo­ida­ble in the medi­um term. An obvious solu­ti­on for redu­cing CO₂ emis­si­ons is elec­tric hea­ting, which does not cau­se any Scope 1 emis­si­ons during ope­ra­ti­on. If the long-term goals of rene­wa­ble ener­gy sup­p­ly in the elec­tric power indus­try are achie­ved, Scope 2 CO₂ emis­si­ons will also approach a value of 0 gCO₂/kWh.

The ther­mal pro­ces­sing indus­try makes a signi­fi­cant con­tri­bu­ti­on to glo­bal CO₂ emis­si­ons and the emis­si­on tar­gets set as part of the ener­gy tran­si­ti­on repre­sent a major chall­enge for this sector.

Pro­cess heat is respon­si­ble for around 25% of glo­bal CO₂ emis­si­ons. Appro­xi­m­ate­ly 17% of tho­se emis­si­ons are attri­bu­ta­ble to indus­tri­al com­bus­ti­on and appro­xi­m­ate­ly 8% to indus­tri­al pro­ces­ses. In order to meet the cli­ma­te tar­gets defi­ned in Ger­ma­ny, a reduc­tion in CO₂ emis­si­ons is necessary.

CO₂-neu­tral pro­cess heat can be gene­ra­ted both by using elec­tric hea­ting tech­no­lo­gies and by bur­ning rene­wa­ble fuels. In order to achie­ve cli­ma­te-neu­tral pro­cess heat, the neces­sa­ry elec­tri­cal ener­gy – inclu­ding that used to pro­du­ce the fuels – has to be sup­pli­ed by rene­wa­ble sources. Pre­vious rese­arch into CO₂ emis­si­on reduc­tion has focu­sed pri­ma­ri­ly on the use of car­bon-free fuels as ener­gy sources and the direct elec­tri­fi­ca­ti­on of ther­mal pro­ces­sing plants.

The goal of this rese­arch and deve­lo­p­ment pro­ject, a col­la­bo­ra­ti­on bet­ween Hyper­Heat GmbH and the Depart­ment for Indus­tri­al Fur­naces and Heat Engi­nee­ring at RWTH Aachen Uni­ver­si­ty, is to deve­lop a novel high-per­for­mance elec­tric pro­cess gas hea­ter as a retro­fit solu­ti­on for the elec­tri­fi­ca­ti­on of ther­mal pro­ces­sing plants. This offers the pos­si­bi­li­ty of repla­cing exis­ting bur­ner tech­no­lo­gy in a direct exch­an­ge wit­hout having to make major modi­fi­ca­ti­ons to the plant or the pro­cess. The elec­tri­fi­ca­ti­on of the pro­ces­ses offers the pos­si­bi­li­ty of com­ple­te­ly avo­i­ding Scope 1 emis­si­ons. The use of elec­tri­ci­ty from rene­wa­ble ener­gies also redu­ces Scope 2 emissions.

In order to retro­fit bur­ners, a gas flow cor­re­spon­ding to the bur­ners com­bus­ti­on has to be pro­vi­ded by the novel pro­cess gas hea­ter. This can only be achie­ved with gas out­let tem­pe­ra­tures from the pro­cess gas hea­ter clo­se to the adia­ba­tic fla­me tem­pe­ra­tu­re of the com­bus­ti­on pre­vai­ling in the sta­te of the art. The adia­ba­tic fla­me tem­pe­ra­tu­re of natu­ral gas-air com­bus­ti­on (air ratio λ = 1.1; cold air input) is 1950 °C. At the­se tem­pe­ra­tures, the use of cera­mic hea­ting ele­ments is unavo­ida­ble. In con­trast to com­pe­ting pro­ducts, the pro­cess gas hea­ter deve­lo­ped and paten­ted by Hyper­Heat GmbH works with oxi­de cera­mic hea­ting ele­ments, which is why pro­cess gas tem­pe­ra­tures in the requi­red tem­pe­ra­tu­re ran­ge are possible.