English to Polish Tech/Engineering Chemistry; Chem Sci/Eng opis patentowy elektrody

Konteksty:

1. The process of production of iron alloys is based on the principle of manufacture through electrometallurgy
which consists in the chemical reduction of one or more minerals, typically in the form of oxides, by means of pit coal
or its derivatives, which therefore act with a reducing function. In said process electric furnaces of the reduction type with resistance arc are used which require the use of electrical energy to supply the smelting heat, which therefore is to be considered as "obligatory electrical use" since the electrical energy cannot be substituted for this production process. More particularly, in the production of ferro-alloys such as ferrosilicon, ferromanganese and ferrochrome, use is made of resistance furnaces with submerged arc (process in arc furnace) which in the production phases have the electrodes immersed in the inorganic charges of the furnace.

2. In the patent application EP 1130077A2 a process is described for the preparation of hydrocarbon binders with
a low PAH content compared to the traditional ones deriving from pit coal which involves subjecting the pitch or tar to combined reactions of cracking, dehydrogenation and polymerisation in order to reduce the content of PAHs to 95% in the pitch thus obtaining PAH emissions lower than 6 mg/m3. This solution however is costly and impracticable in light of the complexity of the plant for pretreatment of the pitch. Moreover it is not described how to avoid the R45 classification of the base electrode pastes. In fact a reduction of PAHs in the paste of up to 95% does not ensure a content of PAHs below 0.1% as foreseen by law to avoid said classification since this content depends on the concentration of PAHs in the pitch or tar used and on the quantity of pitch in the paste.

EP 2 514 269 B1