Methodology for upgrading and cleaning of used tires, waste lubricants as well as any kind of oils and fats for utilization as feedstock in thermochemical conversion processes

Abstract

A methodology for cleaning and upgrading any kind of tires (cars, motorcycles, trucks, etc.), any kind of waste lubricants (internal combustion engines, industrial parts), any kind of oils as well as plant and animal fats by means of removal of the inorganic elements (potassium, sodium, chlorine, sulfur, phosphorus and heavy metals such as Pb, Cu, Cd, Zn, Hg, Mn, etc.) and the simultaneous addition of new such as calcium, magnesium and ammonium, in order to produce a clean and upgraded rubber material, lubricant as well as fat/oil, which can be used as raw material in thermochemical conversion processes such as flash (t<1 sec)/fast pyrolysis.

Claims

1. A method for leaching a raw material comprising at least one selected from the group consisting of tires, waste lubricants, vegetable oils, and animal fats, the method comprising: a) contacting the raw material with an aqueous solution comprising a salt or salt mixture in a reactor under leaching conditions to remove inorganic elements of potassium, sodium, chlorine, sulfur, phosphorus, copper, lead, zinc, chromium, mercury, cadmium, manganese, nickel, vanadium, barium, and molybdenum while adding calcium, magnesium, aluminum and ammonium to produce an upgraded material, wherein: the salt or salt mixture comprises calcium and a total amount of salt or salt mixture in the aqueous solution is 0.5 to 4 wt %, the leaching conditions include a temperature of 110 C. to 250 C., a pressure of 2 to 45 atm, and a time of 1 min to 2 h, and a pH within the reactor is kept neutral or basic; b) separating an aqueous phase from the upgraded material.

2. The method according to claim 1, wherein the aqueous solution comprises at least one inorganic calcium salt and/or at least one organic calcium salt.

3. The method according to claim 1, wherein the raw material comprises tires.

4. The method according to claim 1, wherein the aqueous solution further comprises a magnesium salt and/or an ammonium salt.

5. The method according to claim 1, wherein step a) further comprises sequentially contacting the raw material with an aqueous solution comprising a magnesium salt and contacting the raw material with an aqueous solution comprising ammonium salt.

6. The method according to claim 1, wherein water from a public water system is employed to create the aqueous solution and a ratio of raw material to aqueous solution ranges from 15 grams per liter to 800 grams per liter.

7. The method according to claim 1, wherein the raw material comprises tires, water from a public water system is employed to create the aqueous solution, and a ratio of raw material to aqueous solution ranges from 15 grams per liter to 800 grams per liter.

8. The method according to claim 1, wherein a ratio of raw material to aqueous solution ranges from 140 grams per liter to 800 grams per liter.

9. The method according to claim 1, wherein the raw material comprises tires and a ratio of raw material to aqueous solution ranges from 140 grams per liter to 800 grams per liter.

10. The method according to claim 1, wherein the leaching time is 5 to 30 min.

11. The method according to claim 10, wherein step a) includes mixing the raw material and the aqueous solution and a leaching time of 5 to 20 minutes.

12. The method according to claim 1, wherein the temperature is 110 C. to 150 C. and the pressure is 2 to 7 atm.

13. The method according to claim 1, wherein any alkali metals, chlorine, sulfur, phosphorus, copper, lead, zinc, chromium, mercury, cadmium, manganese, nickel, vanadium, barium, and/or molybdenum present in the raw material are transferred to the aqueous phase during the contacting and are separated with the aqueous phase.

14. The method according to claim 1, further comprising separating at least a portion of an aqueous phase rich in at least one of alkali metals, chlorine, sulfur and phosphorus from the aqueous phase, wherein the at least a portion of the aqueous phase is used as liquid fertilizer.

15. The method according to claim 1, wherein the aqueous solution is fed to the reactor using a pressure pump.

16. The method according to claim 1, wherein the reactor comprises a direct discharge valve which communicates with an interior of the reactor via a pipeline with an end having a 40 micron diameter solids filter, and wherein the method further comprises: i) separating the aqueous phase from the upgraded material by passing the upgraded material through the direct discharge valve and solids filter to produce the aqueous phase and a solid phase, ii) cooling the aqueous phase in a tank to produce a cooled aqueous phase, iii) recycling at least a portion of the cooled aqueous phase to step a), and iv) removing the solid phase from the direct discharge valve by opening the direct discharge valve.

Description

EXAMPLE 1

(1) Used motorcycle tires are treated at atmospheric conditions utilizing calcium nitrate as solvent. The applied conditions are the following: temperature 80 C., solid/liquid ratio 15% w/w dry basis, agitator use at 500 rpm, leaching time 20 minutes, solvent concentration 3% w/w, material particle size <5 mm. After the pretreatment, the sample is filtered and dried at 50 C. After the pretreatment, 1.5% weight increase of the treated dry material is noticed because of the calcium absorption by the material. Sample analysis by electron microscopy, SEM-EDX confirms the significantly increased calcium concentration in the sample as well as the absence of chlorine and alkali metals while the sulfur concentration appears to be significantly reduced by 10-20%. Then both the untreated and the treated material are used in fast pyrolysis tests (t=2 sec) at 600 C. and 800 C. These tests showed that the material conversion into gaseous and liquid products as increased from 35.7 to 62.5% at 600 C. and from 75 to 91.1% at 800 C. after pretreatment. At the same time, although SO.sub.2 was produced in the final gaseous and liquid products during pyrolysis of the raw material, there was no presence of SO.sub.2, in case of the treated material. Additionally, the production of liquid hydrocarbons appears to be decreased by more than 70% in case of the treated sample while the primary end product is a gas mixture rich in H.sub.2, CO, CH.sub.4, and other hydrocarbons.

EXAMPLE 2

(2) Used motorcycle tires are treated at elevated pressure using the reactor shown in FIGURE utilizing calcium chloride as solvent. The applied conditions are the following: temperature 140 C., pressure 7 atm, solid/liquid ratio 25% w/w dry basis, leaching time 4.5 minutes, solvent concentration 4% w/w, material particle size <5 mm. After the pretreatment, the sample is dried at 50 C. After the pretreatment, 1.9% weight increase of the treated dry material is noticed because of the calcium absorption by the material. Sample analysis by electron microscopy, SEM-EDX confirms the significantly increased calcium concentration in the sample as well as the absence of chlorine and alkali metals while the sulfur concentration appears to be significantly reduced by 15-30%. Then both the untreated and the treated material are used in fast pyrolysis tests (t=2 sec) at 600 C. and 800 C. These tests showed that the material conversion into gaseous and liquid products was increased from 35.7 to 73% at 600 C. and from 75 to 93% at 800 C. after pretreatment. At the same time, although SO.sub.2 was produced in the final gaseous and liquid products during pyrolysis of the raw material, there was no presence of SO.sub.2 in case of the treated material. Additionally, the production of liquid hydrocarbons appears to be decreased by more than 80% in case of the treated sample while the primary end product is a gas mixture rich in H.sub.2, CO, CH.sub.4, and other hydrocarbons.

EXAMPLE 3

(3) Waste cooking oil from waste cooking oil recycling company RENOVOIL is treated at atmospheric conditions utilizing calcium acetate as solvent. The applied conditions are the following: temperature 30 C., oil/liquid ratio 25% weight basis, agitator use at 500 rpm, leaching time 20 minutes, solvent concentration 3% w/w. After the pretreatment, the sample is separated from the liquid phase using a separating funnel. The concentrations of chlorine, sulfur, alkali metals, calcium, magnesium, heavy metals, etc., in both raw and treated oil are determined by using ion chromatography and ICP-AES. The results show 99.9% chlorine removal, more than 35% sulfur removal, alkali metals removal by more than 55% for sodium and 99% for potassium while heavy metals removal such as V, Cu, Ba, Mo, Mn ranges from 30-80%. At the same time, the calcium concentration in the treated oil is significantly increased. Then both the untreated and the treated material are used in fast pyrolysis tests (t=2 sec) at 600 C. and 800 C. These tests showed that the material conversion into gaseous and liquid products was increased from 40 to 75% at 600 C. and from 55 to 90% at 800 C. after pretreatment. At the same time, although SO.sub.2 was produced in the final gaseous and liquid products during pyrolysis of the raw material, there was no presence of SO.sub.2 in case of the treated material.

(4) Additionally, the production of liquid hydrocarbons appears to be decreased by more than 75% in case of the treated sample for both temperatures while the primary end product is a gas mixture rich in H.sub.2, CO, CH.sub.4, and other hydrocarbons

EXAMPLE 4

(5) Waste cooking oil from waste cooking oil recycling company RENOVOIL is treated at elevated pressure using the reactor shown in FIGURE utilizing calcium chloride as solvent. The applied conditions are the following: temperature 140 C., pressure 6 atm, oil/liquid ratio 25% weight basis, leaching time 4.5 minutes, solvent concentration 2.5% w/w. After the pretreatment, the sample is separated from the liquid phase using a separating funnel. The concentrations of chlorine, sulfur, alkali metals, calcium, magnesium, heavy metals, etc., in both raw and treated oil are determined by using ion chromatography and ICP-AES. The results show 99.9% chlorine removal, more than 35% sulfur removal, alkali metals removal by more than 55% for sodium and 99% for potassium while heavy metals removal such as V, Cu, Ba, Mo, Mn ranges from 30-80%. At the same time, the calcium concentration in the treated oil is significantly increased. Then both the untreated and the treated material are used in fast pyrolysis tests (t=2 sec) at 600 C. and 800 C. These tests showed that the material conversion into gaseous and liquid products was increased from 40 to 75% at 600 C. and from 55 to 90% at 800 C. after pretreatment. At the same time, although SO.sub.2, was produced in the final gaseous and liquid products during pyrolysis of the raw material, there was no presence of SO.sub.2 in case of the treated material. Additionally, the production of liquid hydrocarbons appears to be decreased by more than 75% in case of the treated sample for both temperatures while the primary end product is a gas mixture rich in H.sub.2, CO, CH.sub.4, and other hydrocarbons.

EXAMPLE 5

(6) Corn oil is treated at atmospheric conditions utilizing initially citric acid and then calcium acetate as solvent. Each wash is carried out separately while the treated material is separated from the first solvent using a separating funnel before being treated with the second. The applied conditions are the following: temperature 30 C. for citric acid and 20 C. for calcium acetate as solvents, oil/liquid ratio 25% weight basis, agitator use at 500 rpm, leaching time 20 minutes (10 minutes with the acid and 10 minutes with the acid salt), citric acid concentration 0.25% weight basis, calcium acetate concentration 0.2% weight basis. After the pretreatment, the sample is separated from the liquid phase using a separating funnel. The concentrations of chlorine, sulfur, alkali metals, calcium, magnesium, heavy metals, etc., in both raw and treated oil are determined by using ion chromatography and ICP-AES. The results show 99.9% chlorine removal, more than 40% sulfur removal, more than 25% phosphorus removal, alkali metals removal by more than 60% for sodium and 99% for potassium while heavy metals removal such as V, Cu, Ba, Mo, Mn ranges from 30-90%. At the same time, the calcium concentration in the treated oil is significantly increased. Then both the untreated and the treated material are used in fast pyrolysis tests (t=2 sec) at 600 C. and 800 C. These tests showed that the material conversion into gaseous and liquid products was increased from 45 to 73% at 600 C. and from 51 to 92% at 800 C. after pretreatment. Additionally, the production of liquid hydrocarbons appears to be decreased by more than 78% in case of the treated sample for both temperatures while the primary end product is a gas mixture rich in H.sub.2, CO, CH.sub.4, and other hydrocarbons.

EXAMPLE 6

(7) Sunflower oil is treated at atmospheric conditions utilizing calcium acetate/magnesium acetate ratio: 60/40 as solvent. The applied conditions are the following: temperature 30 C., oil/liquid ratio 65% weight basis, agitator use at 500 rpm, leaching time 20 minutes, solvent concentration 4% weight basis. After the pretreatment, the sample is separated from the liquid phase using a separating funnel. The concentrations of chlorine, sulfur, alkali metals, calcium, magnesium, heavy metals, etc., in both raw and treated oil are determined by using ion chromatography and ICP-AES. The results show 99.9% chlorine removal, more than 30% sulfur removal, alkali metals removal by more than 75% for sodium and 99% for potassium while heavy metals removal such as V, Cu, Ba, Mo, Mn ranges from 30-85%. At the same time, the calcium as well as the magnesium concentration in the treated oil is significantly increased. Then both the untreated and the treated material are used in fast pyrolysis tests (t=2 sec) at 600 C. and 800 C. These tests showed that the material conversion into gaseous and liquid products was increased from 44 to 77% at 600 C. and from 49 to 89% at 800 C. after pretreatment. Additionally, the production of liquid hydrocarbons appears to be decreased by more than 80% in case of the treated sample for both temperatures while the primary end product is a gas mixture rich in H.sub.2, CO, CH.sub.4, and other hydrocarbons.