US 2026/0286233 A1 · PROCESS TO PRODUCE A PYROLYSIS OIL COMPRISING LIQUID HYDROCARBONS FROM PLASTIC MATERIAL FROM AN INTERMITTENT ENERGY SOURCE, AND RELATIVE PLANT

Abstract

Process for producing a pyrolysis oil comprising liquid hydrocarbons from plastic material, preferably waste material. The process is characterized by the use of an energy source preferably of an intermittent nature (and of variable intensity), such as for example solar radiation. The plastic material enters a pyrolysis reactor, heated with a molten salt thermal fluid. Said molten salts are heated by said intermittent source to a temperature that is not fixed but variable within a predetermined range. In particular, when the availability of the energy source is equal to or beyond a predetermined maximum value, the temperature of said molten salts is brought to the upper end of said range. Conversely, when the availability of the energy source is equal to or lower than a predetermined minimum value, the temperature of said molten salts is brought to the lower end of said range. For intermediate availability values, the temperature can also be brought to intermediate values, for example by following a linear profile. The pyrolysis temperature follows the temperature of the molten salts. The pyrolysis pressure, on the other hand, is modulated so that it is higher (at least 2.5 bara) when the pyrolysis temperature is lower and lower (no more than 2 bara) when the pyrolysis temperature is higher. Surprisingly, it has been discovered that by operating in the specified way, the quality of the pyrolysis oil obtained is kept constant, even for significant variations in the pyrolysis temperature.

Claims23

Dependent claims

A process to produce at least a pyrolysis oil from essentially plastic material using variable-intensity energy sources which comprises the steps of:

a. heating a heat transfer fluid to a temperature (THTF) comprised between 350° C. and 700° C. by means of a variable-intensity energy source;
b. heating a pyrolysis reactor by means of the heated heat transfer fluid;
c. feeding the essentially plastic material, optionally already in the molten and/or preheated state, to a pyrolysis reactor;
d. bringing said material in said pyrolysis reactor to a temperature (TMPR) between 330° C. and 650° C. in the substantial absence of oxygen and at a pressure of between atmospheric pressure and 20 bar(a) using said variable-intensity energy source;
e. holding said material in said pyrolysis reactor at a temperature (TMPR) of between 330° C. and 650° C. for a time sufficient to produce at least one effluent in the gaseous state in said pyrolysis reactor;
f. keeping the composition of the pyrolysis oil produced substantially constant by dynamically adjusting the pressure in said pyrolysis reactor in relation to a reference temperature (TREF), which is either the said temperature of said heated heat transfer fluid (THTF) or the said temperature of the material in said pyrolysis reactor (TMPR), at a value between atmospheric pressure and 20 bar(a);
g. partly or totally condensing said effluent in the gaseous state so as to form at least one liquid fluid quantitatively being at least 10% by mass with respect to the mass of essentially plastic material fed, and which comprise hydrocarbons that have a standard boiling point not below 25° C.

4 more elements

Dependencies are inferred from the claim text.

Process to produce a pyrolysis oil comprising liquid hydrocarbons from plastic material from an intermittent energy source, and relative plant

Life of this patent

Process to produce a pyrolysis oil comprising liquid hydrocarbons from plastic material from an intermittent energy source, and relative plant

Life of this patent

Abstract

Claims23