Yes, they accept mattresses. See this list for what they can and cannot accept: https://www8.miamidade.gov/global/service.page?Mduid_service=ser1464797123341331
This facility is for disposal. A mattress will be taken to the landfill.
I am not 100% certain that they recycle them, but I do believe they will accept them. Sorry I couldn't be of more help!
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