THE DIGESTING MACHINE
Pratt, GAUD, 2014
Critic: David Ruy
In 2013, the average American produces 4.4 pounds of trash daily, totaling 1600 pounds annually. Forty percent of that trash cannot be recycled. With the garbage produced in America alone, you could form a line of garbage trucks that reach the moon.
The concept is a biodegradable landfill that over time becomes an abomination, a place that causes disgust and hatred. The landfill site can be close to a city in an empty space. First, the machines are placed on the site. Then the engines start to excavate their environment. After all the machines have dug deep enough to sit entirely below ground they can begin functioning as garbage digesters. This is because the machine needs to dig deep enough to receive garbage directly dumped from trucks. With time the excavation grows deeper.
The excavation part of the machine consists of a rotating cutting wheel called a cutter head, followed by the main bearing, a thrust system, and trailing support mechanisms. The outer diameter is 19 m, and the total length is 40 m. The lifecycle of the machine is made up of 2 phases: the excavation phase and installation phase.
1. The Excavation Phase
With its rotating cutting wheels, the machine breaks the material from the earth’s crust. The broken soil is transferred into the pumping mechanism. The hydraulic cylinder presses the pump forward.
During the excavation phase the cutting wheel, whilst rotating, is pressed into the soil with the immense pressure of hydraulic cylinders. Under this high pressure, the disk cutters and the cutting knives made of high strength steel loosen the material at the earth's crust. Though it moves slowly, the machine has the potential to dig up to 350m in 1 week under optimum conditions. For reference, the Empire State Building is 443 m tall. Such a depth would include the removal of 40,000 m3 of excavated material.
The Formation of the Land
2. The Installation Phase
When the excavation phase is completed the installation phase begins. The “pouch” consists of several segments made of a prefabricated material produced in a factory. They are transferred into the machines before the machine is launched. The pouching segments are released individually by a crane. It moves the material from inside of the machine to the landfill. As it excavates the ground and pumps the drilled soil away to the perimeter of the site, the positioning of the pouch segments always follows the same routine, even as the volume of waste material changes. This makes the shape of each individual pouch different. The 20 pouch segments (stomachs) are released continuously from the main body.
How does this landfill work as a productive landscape?
Imagine many giant plastic pouches in the ground covered by the crushing engines. Waste is added on top of the crushing engines and chewed daily by the engines. After the trash becomes smaller, it falls into the plastic pouch. The system is similar to a living creature.
Large amounts of decomposing waste create methane gas build up. Methane is produced in the absence of oxygen, a result of anaerobic organic waste breakdown. This greenhouse gas can kill surface vegetation and is 34 times more potent as a green house gas in comparison to carbon dioxide. This project transports methane gas with a piping system to storage balloons. These balloons can be sold off to power cities or sent long-distance with natural gas pipelines. This requires the gas to be processed into pipeline quality by removing the water, carbon dioxide, nitrogen, hydrogen, oxygen, and any other trace contaminants. Once in the general supply of natural gas, it can be used at power plants producing electricity or in househoulds.
Any rain or snow that seeps into the cover starts to trickle down into the waste. When water and waste are mixed it creates a toxic poisonous soup called leachate. Leachate contains all of the hazardous material found in household waste. It consists of thousands of chemicals, heavy metals and other toxic materials found in electronics, batteries, prescription drugs and plastics which then filter through the waste and eventually pool at the bottom.
After 200 years the lifecycle of the digesting landfill ends. During this time some of the machines will stop working, however, none of those machines are replaced. Instead of reassembling, the machine will remain as an implant for the earth. Machine and earth will symbolically and visually merge. It will be a permanent scar on the face of the Earth.