Trash incinerator

A trash incinerator has an effective stack height of 100 m. On a sunny day with a 2 m/s wind the concentration of sulfur dioxide 200 m directly downwind is measured at 5.0 X 10-5 g/m3. Estimate the mass release rate (in g/s) of sulfur dioxide from this stack. Also estimate the maximum sulfur dioxide concentration expected on the ground and its location downwind from the stack. 

Nickel is also found in meteorites and on the ocean floor in lumps of minerals known as sea floor nodules. The earth s core contains large amounts of nickel. Nickel is released into the atmosphere during nickel mining and by industries that make alloys or nickel compounds or industries that use nickel and its compounds. These industries may also discharge nickel in waste water. Nickel is also released into the atmosphere by oil-burning power plants, coalburning power plants, and trash incinerators. 

Nickel may be released to the environment from the stacks of large fiirnaces used to make alloys or from power plants and trash incinerators. The nickel that comes out of the stacks of power plants is attached to small particles of dust that settle to the ground or are taken out of the air in rain. It usually takes many days for nickel to be removed from the air. If the nickel... 

Gas-solid Fluidized beds Trash incinerators Catalytic crackers Coal gasification Reformers Ore processing... 

There are subtle reasons why venting carbon dioxide from trash incineration is of far less concern than the venting of the same gas from fossil fuel combustion reactions. Large portions of the carbon compounds in domestic trash are paper and food wastes. Only a few years ago the carbon contained in these plant products was part of the atmosphere. On a long-term basis, returning this carbon to the atmosphere has no effect on the overall carbon dioxide balance it simply speeds up the rate of recycle of carbon from plant material to the biosphere. 

LLDPE can be disposed of by landfill or incineration. In landfill, the material is completely inert, degrades very slowly, does not produce gas, and does not leach any pollutants into ground water. When incinerated in commercial or municipal faciHties, LLDPE produces a large amount of heat (the same as heating fuel) and should constitute less than 10% of the total trash. 

Low-Level Waste Low-level waste (LLW) consists of contaminated dry trash, paper, plastics, protective clothing, organic liquids such as liquid scintillation samples, and the like. LLW is produced by any facility that handles radioactive materials such as nuclear power plants, medical facilities, colleges, and so forth. In the United States, commercial LLW is sent to one of three disposal sites (Barnwell, South Carolina, Richland, Washington, and Clive, Utah). Due to the limited size of these sites (and similar disposal sites through the world) and steeply escalating costs for waste disposal, the primary goal of LLW treatment prior to disposal is volume reduction, either by incineration or compaction, followed... 

The trash feed system consists of a high-efficiency cyclone that is equipped with a vacuum feeder that discharges into a screw conveyor. As the waste moved progressively through the lower chamber due to the additional charges of trash, it is reduced to ash and discharged from the incinerator by the automatic ash removal cylinder. 

The incinerator has operated on the controlled-air principle with minimum excess air. The lower chamber of the incinerator is equipped with two natural gas burners to ignite the trash and help preheat the chamber during initial startups. Those burners can be completely turned off when preheating has been accomplished The upper chamber is equipped with one burner to insure ignition of the smoke in the upper chamber. This burner is automatically turned off by a controller at about 1,400°F. Ignition is self-sustaining above this temperature. 

The successful operation of this system demonstrated the potential for heat recovery from incineration of cotton gin trash. At a 30% recovery ratio, enough heat can be recovered from the incineration process to supply most of the energy required for seed cotton drying, even in low-capacity gins (Table IX). Only the size and volume of the ginning operation will dictate whether such recovery will be economically feasible. 

Table IX. Potential for Heat Recovery from Incineration of Gin Trash.

One of the biggest concerns people have is that the bottles and cans they throw away today will either accumulate in unsightly, unsanitary landfills or go up in smoke from an incinerator. But the fact of the matter is that new waste treatment facilities in nearby counties soon will eliminate most of the need for landfills and incinerators. By compacting unsorted trash into blocks comparable in hardness to concrete, the new facilities make it available for use in building foundations, dikes, and road construction. This form of recycling — not part of the present proposal — doesn t require us to collect the garbage in any new way because it doesn t matter whether the content is coffee grounds or juice bottles. 

Incineration of waste offers an advantage. Less land is ruined in disposal of the solid ash left after incineration. In some cases, the heat from incineration has been used to generate electricity. Despite advantages over landfills, simple incineration with or without electrical generation has not proven to be a quality method of solid waste disposal. Trash is a poor fuel so it does not produce a hot fire when it... 

The low temperature generated by burning trash with air is far from optimum for the generation of power. The corrosive and toxic materials produced by the combustion process attack the incineration equipment and the boiler reducing their service life. The high level of toxic materials leads to the requirement for costly scrubbers and filters to meet the desired level of output quality. 

The high temperature gas resulting from the oxygen-enhanced combustion of trash is more useful for the generation of electricity than is the relatively cooler gas generated from incineration of trash with... 

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