21st Century Municipal Waste Management
Process and Technology

The process of steam-cooking is an ancient technology, having been discovered by various cultures over 6000 years ago. The high-pressure steam autoclave was invented by a French scientist in 1879 to sterilize and disinfect medical instruments. Such autoclaves are now commonly used in healthcare, laboratories, and commercial food preparation.

High-pressure steam and mechanical forces in a rotating vessel significantly alter the weight of the municipal solid waste while also sterilizing it. During the process...

- Glass products are broken into aggregate-sized pieces.
- Plastic products shrink and ball-up.
- Metals are cleaned and crushed
- Labels are stripped off. 
- Fibers from food and paper stocks, and vegetable wastes and small wood chips, are thermo-mechanically pulped
- Meat wastes are stripped from bone:  the residual meat is reduced to connective tissue fibers.

In addition, many common household chemicals are hydrolyzed and detoxified. With water, fiber, and metals removal, the residual waste weight is typically less than 20% of the original weight.  The remainder is sterile and inert -- free of pathogens, litter, and decaying material that attract vermin and flies.

Estech’s proven and proprietary Fibrecycle autoclave process is an elegantly simple and robust system that sterilizes, reduces, and sorts municipal waste.

Through the process, at least 80% of the waste stream is separated as dry fiber and water.  Processed wastes can be safely sorted. With fiber, water, and metals removed, less than 20% of the original weight remains to be land filled.

Here we see a Fibercycle plant on a 5-acre site. The plant contains:
- An inbound waste-tipping floor
- A main processing area with 2 steam autoclaves and pre- and post-treatment equipment
- And a product separations/recycled materials shipping area, in addition to an office area and a central control room.

The Fibrecycle process begins when waste is fed from a conveyor into one of the autoclave vessels, and is then evenly distributed in the vessel.  The door is hydraulically closed, and vessel rotation begins.

While the vessel rotates, steam is introduced and raised up to 7 atmospheres pressure at about 330 degrees Fahrenheit for a cooking period of 30 minutes.  Processed, sterilized materials are then discharged onto an output conveyor.

The sterilezed material that emerges is without pathogens and has very little odor. This allows for easy sorting and handling of the processed material without the health and safety risks associated with raw municipal waste.

The sterilized waste is next fed into a trommel screen where the dry bulk fiber is separated out. This separated cellulose fiber typically represents  more than 30% of the municipal solid waste stream weight, and well over 60% of the treated volume – representing an enormous reduction in waste volume.

With metals removal, municipal waste weight is reduced by more than 80%.

Dry cellulose fiber has many beneficial uses .  After a detailed examination of its beneficial uses during its developmental period, Estech concluded that the best use for dry fiber was as a solid fuel, thus providing renewable energy from a domestic source.

Our sister company, Slane Energy LLC, blends these fibers with coal fines to manufacture “synthetic” coal briquettes.  These briquettes provide a coal-like fuel with lower emissions, and in some applications, tax incentives and renewable portfolio credits add to the profitability.t

The remainder of the treated waste is conveyed to a sorting station where other valuable products, such as glass, plastic and metals, are extracted for recycling.

Iron and aluminum are easily extracted using magnets and eddy current separators. In the European Fibrecycle model, plastics and glass are also separated and recycled.