vast-, wast-
(Latin: waste, lay waste completely; from vastare, "to make empty, to lay waste", from vastus, "empty, waste, desert")
A process that generates energy from useless, discarded materials; especially, by the incineration of municipal solid wastes or (MSW): The waste-to-energy process utilizes "waste" to generate useful energy; such as, electricity, heat, or both.
This waste-to-energy is possible, and convenient, when the heat generated by burning the "waste" is high enough to warrant satisfactory combustion conditions and to make enough energy available to overcome losses and auxiliary consumption.
Characteristics of waste-to-energy production
- Waste-to-energy is the offspring of the incineration of materials, which were originally introduced to sterilize and to reduce the volume of useless substances by burning it in a furnace.
- Modern waste-to-energy plants allow the export of energy, with very low environmental impact.
- The waste-to-energy plant consists of four basic sections: waste combustor, recovery boiler, flue gas treatment, and steam cycle.
- The design of the combustor varies widely with the waste characteristics: physical state (solid versus liquid), size distribution, heating value, ash and moisture content, etc.
- Municipal solid waste is typically burned on a moving grate, where it is kept 20-30 minutes until it is completely burned.
- The hot gases generated in the combustor go through the recovery boiler to generate steam, which is used directly as a heat carrier or it is sent to a steam turbine to produce power.
- Flue gases are treated by adding reactants called sorbents and by filtering the particulate matter.
- A modern, large plant, treating a half-million tons of municipal solid waste per year, can generate more than 400 million kWh per year, meeting the electricity needs of more than 150,000 families.
Waste-to-energy is the process in which municipal waste is used to generate useful energy for electricity, heat, or both.
Used fluids; a broad term for any liquid that has been used by a household, farm, business, industry, and so on, and then returned to the environment; typically containing dissolved or suspended matter that can cause pollution if not properly treated: The city authorized the building of a treatment plant for the wastewater that was being discharged by various industries and agricultural uses.
1. A channel for carrying away excess water; such as, at a reservoir or dam: The city engineers and Mr. Carlton designed a new wasteweir in an attempt to avoid floods that had plagued the area of the city near the river.
2. An overfall that functions for the escape, or overflow, of superfluous liquids from a canal, reservoir, pond, etc.: A wasteweir is a dam that is built across a river to regulate the flow of water, to divert it, or to change its level.
2. An overfall that functions for the escape, or overflow, of superfluous liquids from a canal, reservoir, pond, etc.: A wasteweir is a dam that is built across a river to regulate the flow of water, to divert it, or to change its level.
The wasteweir is also a term for a barricade for fish; such as, a fence placed in a stream to catch or to keep them from swimming away from the area.
1. Someone who is regarded as being a spendthrift who squanders his or her time and is lazy: Glenda's nephew was a wastrel so she refused to include him in her will.
2. An idler or a good-for-nothing: The wastrel stood around the door of the saloon waiting for someone to give him enough money for a drink.
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2. An idler or a good-for-nothing: The wastrel stood around the door of the saloon waiting for someone to give him enough money for a drink.
