Incinerators and autoclaves are two of the most commonly used equipment for treating medical waste. There are advantages and disadvantages. This article will analyze from multiple perspectives so that readers can better understand the difference between them.

What is incinerator?

Incinerator is a kind of environmental protection equipment that incinerates waste gas, waste liquid, solid waste fuel, medical waste, domestic waste, animal carcasses, etc. It can reduce the waste volume and weight and utilize part of thermal energy of incineration medium.

Working principle

What’s autoclave?

The autoclave uses moist heat steam is used to kill microorganisms and viruses. The process is adopting a vacuum pump to discharge the cold air in the inner chamber and then injects steam. When the temperature reaches 134-138℃ degrees, the pressure reaches 230-240kpa, it will start the sterilization program. The sterilization time will last 10-45min.(It depends on the local medical waste treatment regulation). After sterilization, it will exhaust hot air and dry. Then unloading the sterile waste.

The autoclaves are divided into pre-shredding and post-shredding according to the different shredding time. The pre-shredding is shredding medical waste before sterilization. shredding and sterilization are completed in one sealed chamber. Post-shredding is shredding medical waste after sterilization. The shredder and sterilizer are separated.

 

Pre-shredding autoclave

 

 

Post-shredding autoclave

 

What kind of medical waste does autoclave and incinerator can treat?

  1. Sharps

Autoclaves can treat sharps. But incinerator is not recommended because metal may remain in ash and glass items may blast during incineration which may cause injuries to operators.

  1. Infectious waste

Both autoclaves and incinerator can treat infectious waste.

  1. Pathological waste

Both autoclaves and incinerator can treat infectious waste.

  1. Pharmaceutical waste

Autoclaves cannot treat pharmaceutical waste but incinerator can.

  1. Radioactive waste

Both of them are not recommend to treat the radioactive waste because the elements will be kept in the ash and cause severe problems. It should be sent to a special hazardous waste treatment center.

 

Comparison:

Area requirements for installation: Autoclave VS Incinerator

Incinerator need large installation area. Dioxin poisonous gas produced by incineration endangers human health although it install the air ventilation system. The incinerator cannot be installed in the urban area and upwind of the city. It should be away from human populations and need install 13meters height chimney.

Autoclave needs room size according to different disposal capacity. As it has no toxic emissions, the autoclave installation doesn’t have much limit.

Installation drawing of model MWT-150

 

Let’s take the model MWT-150 as an example. The overall size of autoclave is 2600*2000*2060mm(L*W*H). Place it into a suitable room, connect power, water source and draining pipes. It will work because we have assembled steam generator, water softener, air compressor and other necessary accessories together.

Product links: https://www.sinicmed.com/Product/waste-sterilizer-with-crushers/

Produict video: https://youtu.be/lH_Hv7-KiJM

 

Utility: Autoclave VS Incinerator

Both autoclaves and incinerators needs electricity although large autoclaves can use Municipal boiler to provide steam.

 

Utility Incinerator Autoclave
Electricity Fans, burner, electricity control box will need power Steam generator, vacuum pump, doors control and all electrical parts will need power
Fuel Diesel No
Water For wet scrubbers For steam generator, vacuum pump, cooling
Ventilation Air ventilation system to prevent toxic gases It has bio-filter and cooling system
Drainage For washing and disposing of effluent from scrubbers For used water discharge
Lime For drying the scrubbers NO need

 

 

Expense: Autoclave VS Incinerator

 

UNEP reports the diesel incinerator will cost $275,000 for burning 50kg/hour which meets air pollution standards corresponding to the Stockholm Convention. The most expensive part of this is the exhaust gas treatment system. That’s why some developing countries use incinerator without waste air treatment system. For autoclave, the cost will be $110000 for 80kg/h.

UNEP also estimates treatment costs for autoclaves to be 0.14-0.33US$/kg. And incineration with air pollution control costs US$ 0.27-1.66 per kg.

 

Environmental protection : Autoclave VS Incinerator

Autoclaves causes very low pollution to soil and water. Although it can generate waste water and odors, most of autoclaves have equipped with sewage treatment system and air purification system.

One of the biggest concerns about waste incineration is the production of carcinogenic substances such as dioxins. Although there is an exhaust gas treatment system, sometimes it cannot be completely avoided

 

Efficiency: Autoclave VS Incinerator

Sterilization efficiency can reach 99.99% after high temperature and pressure sterilization for autoclaves. The biological indicator will be used to test the sterilization efficiency. It uses Bacillus stearothermophilus as the spore to make the comparison. Test results are satisfactory.

 

Service life : Autoclave VS Incinerator

No matter it is a sterilizer or an incinerator, daily maintenance can prolong the service life of the equipment.

Autoclaves maintenance comes from:

  • Temperature or pressure sensor failure
  • Pipes leakage
  • Door sealing gasket failure
  • Burnout of heating elements
  • Control panel failure
  • Corrosion and pipe blockage, because of supplied water
  • Shredders failure, if autoclave have

 

It has been observed around the globe that with proper maintenance, autoclaves possibly remain operational for 10-20 years although service life is marked 8-15years (depends on the chamber material)

In incinerators, Photocell, spark electrode, the oil filter element of primary thermocouple, and heated refractory screens may need renewal once in two years. Fire bars approx; every five years; pumps and burner motors may need substitution in 10 years. Manufacturers say the lifespan of their machinery is ten years, but it’s closer to 5 years.

Conclusion

Every technology has pros and cons and this is no different. However, according to the evaluation for the difference of autoclave and incinerator, autoclaves seem to have the upper hand. Either from an environmental point of view or technological autoclaves are better.

No matter which method is chosen, it should be considered according to local policy norms, characteristics of medical waste, budget, traditional customs, etc. Our goal is to create an Eco-friendly and green environment. Make the earth’s living environment better and better