In designing waste recycling systems, energy usage and pollution emissions are considered. However, it is necessary to quantify and compare waste recycling program options. The Second Law of Thermodynamics can be used to explain why a properly designed source-separation recycling program may be better than a centralized recycling program. A centralized program collects mixed waste over a large area and hauls it to a centralized facility. At this centralized facility, workers or machinery separate the wastes for recycling. A source-separation recycling program takes less energy and produces less pollution. These differences have significant implications on efficiency and environmental friendliness.
This article discusses an application of the Second of Law of Thermodynamics in designing recycling programs.
What is the Second Law of Thermodynamics?
The Second Law of Thermodynamics says that every action is accompanied by irreversible entropy or disorder. This disorder is technically at the molecular or atomic level. However, in layman’s terms, entropy describes disorder in human actions, the environment, and others aspects. Every action leads to additional disorder in the universe. Such disorder becomes a permanent part of the universe.
The Second Law of Thermodynamics can be used to evaluate recycling programs. This is possible by comparing the entropy or disorder effects of recycling programs. In a practical sense, entropy and disorder can be measured in terms of energy consumption and pollution generation. Each recycling program produces pollution and consumes energy to recycle waste.
Entropy in Centralized Program & Facility for Waste Recycling
A centralized program that collects mixed waste over a large area and hauls it to a centralized facility for recycling involves more energy for transportation, more energy for waste processing, and more pollution. Such a program produces more entropy in the long term because more energy is involved in transporting waste to the central recycling facility. The waste must travel more than it would if the facility was localized or the processing decentralized.
If a centralized recycling system is used, energy is used in collecting the waste, transporting it over long distance toward the centralized facility, and processing the waste in the facility. Pollution is produced in the transport of waste materials over long distances to the centralized recycling facility. Based on the Second Law of Thermodynamics, all this energy consumption and activity leads to more entropy or disorder in the universe.
Entropy in Source-Separation Recycling Program
A source-separation recycling program involves less energy consumption because less energy is spent in transporting waste materials to the recycling facility. The separation at the source means that less waste is transported to the central facility. Less fuel is used in processing waste. Less pollution is generated from transporting waste to the recycling facility. Based on the Second Law of Thermodynamics, less entropy or disorder is generated from source-separation recycling programs.
The problem with bringing all the waste materials to the central recycling facility is that this step involves spending energy for transportation and generating pollution from the transport of waste to have it recycled.
The centralized recycling system creates more entropy with the transport of waste materials to the central recycling facility. The Second Law of Thermodynamics shows that the localized and decentralized source-separation system is better for people and the environment.
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