Systems and methods for closed-loop recycling of a liquid component of a leaching mixture when recycling lead from spent lead-acid batteries

Patent metadata

Field	Value
Publication number	US-2015368748-A1
Application number	US-201414498798-A
Country	US
Kind code	A1
Filing date	Sep 26, 2014
Priority date	Jun 20, 2014
Publication date	Dec 24, 2015
Grant date	—

Abstract

The present disclosure relates generally to systems and methods for recycling lead-acid batteries, and more specifically, relates to purifying and recycling the lead content from lead-acid batteries. A system includes a reactor that receives and mixes a lead-bearing material waste, a carboxylate source, and a recycled liquid component to form a leaching mixture yielding a lead salt precipitate. The system also includes a phase separation device coupled to the reactor, wherein the phase separation device isolates the lead salt precipitate from a liquid component of the leaching mixture. The system further includes a closed-loop liquid recycling system coupled to the phase separation device and to the reactor, wherein the closed-loop liquid recycling system receives the liquid component isolated by the phase separation device and recycles a substantial portion of the received liquid component back to the reactor as the recycled liquid component.

First claim

1 . A system, comprising:
a reactor that receives and mixes lead-bearing material, a carboxylate source, and a recycled liquid component to form a leaching mixture yielding a lead salt precipitate; a phase separation device coupled to the reactor, wherein the phase separation device isolates the lead salt precipitate from a liquid component of the leaching mixture; and a closed-loop liquid recycling system coupled to the phase separation device and to the reactor, wherein the closed-loop liquid recycling system receives the liquid component isolated by the phase separation device and recycles a substantial portion of the received liquid component back to the reactor as the recycled liquid component.

2 . The system of claim 1 , wherein the closed-loop liquid recycling system comprises a purification device that removes at least one impurity from the received liquid component before recycling.

3 . The system of claim 2 , wherein the at least one impurity comprises dissolved sulfates.

4 . The system of claim 2 , wherein the at least one impurity comprises one or more elements other than lead.

5 . The system of claim 4 , wherein the one or more elements comprise sodium, barium, calcium, antimony, arsenic, tin, or combinations thereof.

6 . The system of claim 2 , wherein the purification device comprises:
another reactor that mixes calcium hydroxide with the received liquid component; and another phase separation device that subsequently removes a resulting calcium sulfate precipitate from the received liquid component before recycling.

7 . The system of claim 2 , wherein the purification device comprises a nanofilter or ion exchange resin.

8 . The system of claim 2 , wherein a dissolved lead salt content of the liquid component is substantially the same before and after the purification device removes the at least one impurity.

9 . The system of claim 1 , wherein the carboxylate source comprises citric acid, a salt of citric acid, acetic acid, a salt of acetic acid, or a combination thereof.

10 . The system of claim 1 , wherein the recycled liquid component is a solution at least 10% saturated in dissolved lead salt.

11 . The system of claim 1 , wherein the closed-loop liquid recycling system receives wash water along with the liquid component from the phase separation device and recycles the wash water along with the liquid component.

12 . The system of claim 1 , wherein the phase separation device comprises a belt dryer, a filter press, a clarifier, or a cyclone separator.

13 . The system of claim 1 , comprising a lead-acid battery processing device that is configured to receive at least one lead-acid battery and grind the at least one lead-acid battery into the lead-bearing material.

14 . The system of claim 1 , comprising a lead salt precipitate treatment device that is configured to receive the lead salt precipitate isolated by the phase separation device and treat the lead salt precipitate to form leady oxide.

15 . The system of claim 14 , wherein the lead salt precipitate treatment device comprises a belt dryer, a spray calciner, a stirred pot reactor, a rotary kiln calciner.

16 . The method of claim 14 , wherein treating comprises reacting the lead salt precipitate with a hydroxide to yield the leady oxide.

17 . A method, comprising:
forming a leaching mixture comprising a lead-bearing material, a carboxylate source, and a recycled liquid component, wherein the leaching mixture generates a lead salt precipitate as the carboxylate source reacts with the lead-bearing material; isolating a liquid component from the lead salt precipitate of the leaching mixture; and recycling at least a portion of the isolated liquid component back into the leaching mixture as the recycled liquid component.

18 . The method of claim 17 , comprising purifying the portion of the isolated liquid component before recycling.

19 . The method of claim 18 , wherein purifying comprises removing at least a portion of one or more sulfates from the portion of the isolated liquid component.

20 . The method of claim 18 , wherein purifying comprises removing at least one dissolved metal other than lead from the portion of the isolated liquid component.

21 . The method of claim 18 , wherein purifying comprises mixing calcium hydroxide with the portion of the isolated liquid component and subsequently removing calcium sulfate precipitate before recycling.

22 . The method of claim 18 , wherein purifying comprises using an ion exchange resin to remove one or more sulfates from the portion of the isolated liquid component.

23 . The method of claim 18 , wherein purifying comprises removing one or more impurities from the portion of the isolated liquid component without substantially removing dissolved lead salt.

24 . The method of claim 17 , wherein isolating the liquid component from the lead salt precipitate comprises using a belt dryer, a filter press, a clarifier, or a cyclone separator to isolate the liquid component.

25 . The method of claim 17 , comprising treating the lead salt precipitate to yield leady oxide after isolating the liquid component from the lead salt precipitate.

26 . The method of claim 25 , wherein treating comprises oxidizing the lead salt precipitate into leady oxide using a belt dryer, a spray calciner, a stirred pot reactor, a rotary kiln calciner, or a combination thereof.

27 . The method of claim 25 , wherein treating comprises reacting the lead salt precipitate with a hydroxide to yield the leady oxide.

28 . A system, comprising:
a closed-loop liquid recycling system coupled to a leaching vessel containing a leaching mixture, wherein the closed-loop liquid recycling system receives a liquid component of the leaching mixture, purifies the received liquid component to generate a purified liquid component having a lower sulfate content than the received liquid component, and provides the purified liquid component to the leaching vessel as part of the leaching mixture.

29 . The system of claim 28 , comprising a phase separation device coupled to the leaching vessel and the closed-loop liquid recycling system, wherein the phase separation device receives the leaching mixture, isolates a lead salt precipitate from the liquid component of the leaching mixture, and provides the liquid component to the closed-loop liquid recycling system.

30 . The system of claim 28 , comprising the leaching vessel that, during operation, receives and mixes a lead-bearing material, a carboxylate source, and the purified liquid component to form the leaching mixture.

31 . The system of claim 28 , wherein the purified liquid component includes lower sulfate content than the received liquid component.

32 . The system of claim 28 , wherein the purified liquid component includes substantially the same amount of dissolved lead salt as the received liquid component.

33 . The system of claim 28 , wherein the leaching mixture comprises water, a lead-bearing material, and a carboxylate source.

34 . The system of claim 33 , wherein the leaching mixture comprises a lead salt precipitate and dissolved lead salt.

35 . The system of claim 33 , wherein the carboxylate source comprises citric acid, a metal citr

Assignees

• Johnson Controls Tech Co

Inventors

• Meissner Eberhard
• Bauer Jürgen
• Spence Matthew A

Classifications

• C22B7/007

  by acid leaching · CPC title

• B01J6/002

  using rotating drums · CPC title

• C22B7/006

  Wet processes · CPC title

• C22B13/045 Primary

  Recovery from waste materials · CPC title

• B01J8/008

  Details of the reactor or of the particulate material; Processes to increase or to retard the rate of reaction (B01J8/0285, B01J8/067, B01J8/087, B01J8/1836 take precedence) · CPC title