Methods and systems for decontamination of pyrolysis oil using modular units

A method of removing metal compounds and non-metal compounds from a mixed plastic waste pyrolysis oil, the method comprising:

• obtaining a mixed plastic waste pyrolysis oil containing metal compounds and non-metal compounds, the non-metal compounds being two or more of silica compounds, halogenated compounds, phosphorous compounds, oxygenates, and nitrogenates;
• passing the mixed plastic waste pyrolysis oil through a filter medium to remove a portion of solid particles greater than about 10 microns from the mixed plastic water pyrolysis oil to produce a filtered mixed plastic waste pyrolysis oil;
• cooling the filtered mixed plastic waste pyrolysis oil to a temperature at least below 50° C.;
• introducing the filtered mixed plastic waste pyrolysis oil into a coalescing unit having a coalescing medium to separate at least a portion of water from the filtered mixed plastic waste pyrolysis oil;
• passing the filtered mixed plastic waste pyrolysis oil through a first medium in a first trap to remove a portion of the metal compounds from the filtered mixed plastic waste pyrolysis oil;
• passing the filtered mixed plastic waste pyrolysis oil from the first trap through a second medium in a second trap to remove a portion of the silica compounds from the filtered mixed plastic waste pyrolysis oil;
• passing the filtered mixed plastic waste pyrolysis oil from the second trap through a third medium in a third trap to remove a portion of the halogenated compounds from the filtered mixed plastic waste pyrolysis oil;
• conveying the filtered mixed plastic waste pyrolysis oil from the third trap to a molecular sieve unit with a plurality of molecular sieves, each of the plurality of molecular sieves containing pores therein that adsorb at least a portion of the oxygenates or nitrogenates or phosphorous compounds from the filtered mixed plastic waste pyrolysis oil to produce a partially decontaminated pyrolysis oil;
• supplying the partially decontaminated pyrolysis oil to a hydrogenation unit;
• and
• processing the partially decontaminated pyrolysis oil in presence of a hydrogenation catalyst in the hydrogenation unit to convert at least a portion of the olefin compounds in the partially decontaminated pyrolysis oil into one or more saturated hydrocarbon compounds and to produce a decontaminated hydrogenated pyrolysis oil with a reduced amount of the metal compounds and the non-metal compounds as compared to the amount of the metal compounds and the non-metal compounds in the mixed plastic waste pyrolysis oil.

A modular system for removing metal compounds and non-metal compounds from a mixed plastic waste pyrolysis oil, the modular system comprising:

• a filter having a first inlet and a first outlet, the first inlet connected to and in fluid communication with a mixed plastic waste pyrolysis oil feed, the filter configured to remove solid particles greater than about 10 microns from the mixed plastic water pyrolysis oil feed to produce a filtered mixed plastic waste pyrolysis oil;
• a coalescing unit having a second inlet and a second outlet, the second inlet connected to and in fluid communication with the first outlet, the coalescing unit containing a coalescing medium to separate water from the filtered mixed plastic waste pyrolysis oil;
• a metals adsorption bed having a third inlet and a third outlet, the third inlet connected to and in fluid communication with the second outlet, the metals adsorption bed having a first porous bed material to adsorb a portion of metal compounds from the filtered mixed plastic waste pyrolysis oil;
• a silica adsorption bed having a fourth inlet and a fourth outlet, the fourth inlet connected to and in fluid communication with the third outlet, the silica adsorption bed having a second porous bed material to adsorb a portion of silica compounds from the filtered mixed plastic waste pyrolysis oil, pores of the second porous bed material being smaller in size than pores of the first porous bed material;
• a halogenated compounds adsorption bed having a fifth inlet and a fifth outlet, the fifth inlet connected to and in fluid communication with the fourth outlet, the halogenated compounds adsorption bed having a third porous bed material to adsorb a portion of halogenated compounds from the filtered mixed plastic waste pyrolysis oil, pores of the third porous bed material being smaller in size than the pores of the second porous bed material and the pores of the first porous bed material;
• a molecular sieve unit containing a plurality of molecular sieves and having a sixth inlet and a sixth outlet, the sixth inlet connected to and in fluid communication with the fifth outlet, each of the plurality of molecular sieves adsorbing a portion of oxygenates or nitrogenates or phosphorous compounds from the filtered mixed plastic waste pyrolysis oil passing through the molecular sieve unit;
• and
• a hydrogenation unit having a seventh inlet, the seventh inlet connected to and in fluid communication with the sixth outlet of the molecular sieve unit and receiving the filtered mixed plastic waste pyrolysis oil therefrom, the hydrogenation unit having a hydrogenation catalyst therein and being operable to convert at least a portion of olefin compounds in the filtered mixed plastic waste pyrolysis oil into one or more saturated hydrocarbon compounds and produce a decontaminated hydrogenated pyrolysis oil with a reduced amount of plurality of metal compounds and non-metal compounds as compared to the amount of plurality of metal compounds and non-metal compounds in the mixed plastic waste pyrolysis oil.