As a former machinist and mechanical maintenance engineer by trade, I can attest crematoriums are a strange beast to work on. Bone fragments are left over because the crucible like structures in which bodies are immolated reach a relatively low temperature. Industrial processes routinely eclipse these by orders of magnitude and in doing so effectively vaporize and destroy anything left over. Alas, customers want proof and so certain inefficiencies are tolerated in order to deliberately generate an ash byproduct.
Most crematoriums include elaborate air filtration systems. These are far and away better scrubber systems than you would find at a chemical refinery but the media lifespan is very low, and the maintenance cost of these devices is nontrivial. The cost is worth it however...the stench of burning bodies is to be avoided in any way considering most crematoriums are adjacent to fairly residential areas. Most furnaces have a 'hard stop' at a certain number of operations to prevent any possibility of overwhelming the filters. There is also a specific mass limit to each cremation chamber, not unlike a normalizing furnace or heat treatment furnace.
Crematoriums hate two things as far as i can gather: medical implants and the obese. If enough furnace matter includes exotic plastics and metals, some fairly dangerous conditions can occur. certain plastics and magnesium parts for example can trigger a fire inside the furnace that can easily damage or destroy it. Crematorium furnaces are equipped with, in my opinion, a very limited amount of thermal refractory material compared to other industrial furnaces.
Finally the sad truth about obesity is that you'll pay triple for a cremation. Obesity increases the combustion byproduct and shortens the furnace filter and burner lifespan as it increases the time required to properly cremate the remains. large enough people require multiple furnaces.
Our thermal plant has a maintenance engineer that also works on crematorium ovens. I found him muttering, cursing, and swearing one day, obviously very irate, as he fiddled with some of our heating systems. I enquired, mainly to make light conversation, and he went on a tirade about home cheapskate crematorium manager had skimped on maintenance and that this had resulted in a breakdown mid-way through a ’ceremony’ and had required ”pulling the client out when he was only half done” and letting the chamber cool down so that the relevant part could be accessed.
That was really quite a nauseating thought. Must make for the shittiest maintenance request ever.
When they cremate pets they just toss a bunch of animals in the bin at the same time and then give each pet owner a proportionate amount of combined ash.
That's the low-cost option. When I had my cat cremated I opted for private cremation where each pet gets their own vessel in the crematory. (There can still be a tiny bit of ash mingling, as sometimes air currents will carry some flakes into adjacent vessels.)
That's the standard (cheaper) approach, but you can also pay a little more to have your pet cremated alone and get their ashes. My wife works in the funeral industry and she's done this with all of her pets that she's lost.
Most crematoriums include elaborate air filtration systems. These are far and away better scrubber systems than you would find at a chemical refinery but the media lifespan is very low, and the maintenance cost of these devices is nontrivial. The cost is worth it however...the stench of burning bodies is to be avoided in any way considering most crematoriums are adjacent to fairly residential areas. Most furnaces have a 'hard stop' at a certain number of operations to prevent any possibility of overwhelming the filters. There is also a specific mass limit to each cremation chamber, not unlike a normalizing furnace or heat treatment furnace.
Crematoriums hate two things as far as i can gather: medical implants and the obese. If enough furnace matter includes exotic plastics and metals, some fairly dangerous conditions can occur. certain plastics and magnesium parts for example can trigger a fire inside the furnace that can easily damage or destroy it. Crematorium furnaces are equipped with, in my opinion, a very limited amount of thermal refractory material compared to other industrial furnaces.
Finally the sad truth about obesity is that you'll pay triple for a cremation. Obesity increases the combustion byproduct and shortens the furnace filter and burner lifespan as it increases the time required to properly cremate the remains. large enough people require multiple furnaces.