CN1190179A

CN1190179A - Garbage drying method using preheated air

Info

Publication number: CN1190179A
Application number: CN98110636A
Authority: CN
Inventors: 朱平生
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-01-23
Filing date: 1998-01-23
Publication date: 1998-08-12

Abstract

Flue gas is used to preheat comburant air and the comburant air is then used to stove garbage.

Description

New method with the preheated air garbage drying

Employing is burnt away the refuse and with the domestic waste of be situated between determining the reason that the pollution problem of surrounding environment obtains more people at home and abroad just gradually is situated between, approval, and promote rapidly.The burning of house refuse can reach and subtract appearance, sterilization, the purpose of minimizing landfill land used.

Can keep a higher temperature levels for making when the incinerator stove is inherent to be moved, the house refuse that enters incinerator must have higher calorific value.Because the house refuse calorific value of the gap developed country of living standard is high far beyond developing country.Statistics shows that general developed country house refuse calorific value is 6270～10450 kilojoule/kilograms.And domestic house refuse calorific value is only about 3344 kilojoule/kilograms.(1)P.110。Be situated between and certainly contain a large amount of cinders, dust etc. are the smooth combustion problem of the house refuse of flammable discarded object not, can take letter sorting, and natural air drying adds auxiliary fuel to incinerator, and measures such as oven dry can burn house refuse to improve the operation furnace temperature in incinerator.The statistical information table open-birth is lived in the rubbish, and (1) P.110 in 20～60% scopes for water content.The reduction that the existence of moisture is serious the heat of rubbish, furnace temperature is reduced, firing rate is slow, even is difficult to keep stable fired state.The existence of moisture is very big to the influence of the calorific value of rubbish, according to Mendeleev's formula:

Q=339C+1030H-109 (O-S)-25W kilojoule/kilogram (2) P.415

C in the formula, H ... in generation, is with the absolute value of each component content percentage in 100 kilograms of fuel.If adopt baking operation make in the rubbish water content reduce 35% by following formula as can be known calorific capacity will improve Q=W * 35=25 * 35=875 kilojoule/kilogram.This shows that oven dry can improve the calorific value of rubbish significantly, thereby improve temperature levels and firing rate in the incinerator.

Increasingly mature along with garbage incineration process paid attention to by the people day by day to the preheating and drying technology of rubbish before burning, patent No. CN85105948A and patent No. CN87103229A have promptly reflected some research achievements of this respect in recent years.But this two patent all need use water vapour as intermediate medium, and flue gas makes the water endothermic gasification by water vapour heat be passed to rubbish again with the indirect heat transfer form by boiler wall earlier.Its water vapour also needs Special Equipment with separating of air, thus above two kinds make the required intermediate link of mode of drying garbage numerous, the equipment complexity.In number of patent application 971066345, use out kiln gas directly to dry the method for rubbish, but the foul smell that this drying mode volatilizes when oven dry rubbish will be sneaked in the flue gas, if follow-up operation can not be with its thorough removing, then the flue gas of discharging from chimney will pollute surrounding environment.

During bulk cargo oven dry operation is that the large quantity of moisture of bed of material inside can in time be evaporated, and must make heat can import bed of material inside rapidly into.Rubbish belongs to loose indefinite form bulk cargo body, and internal thermal resistance is very big, relies on the slow motion of fire grate to be difficult to make heat to import moist rubbish internal layer rapidly in incinerator as adopting.The present invention proposes to set up an independent rotating drum type drying machine outside incinerator, sees accompanying drawing.Among the figure: the 1-feed screw; The 2-cylindrical shell; The 3-discharging is cut down; The outlet of 4-preheated air; The import of 5-preheated air; 6-holds in the palm metal plate; 7-rubbish; The 8-preheated air.Barrel configuration is simple, reliable operation.Add hot-air earlier with the air preheater that is arranged in the flue, again the hot-air of preheating is introduced in the rotating cylinder, rubbish carries at the holder metal plate of oven dry rotating cylinder inwall and is scattered in the hot air flow that flows in the tube after being thus lifted to suitable height with rotatablely moving of rotating cylinder down, thereby can fully directly contact the intensification drying with high-temperature hot air.Though this diabatic process thermal resistance is bigger than patent 971066345, but this patent No. exists the problem that the discharging flue gas easily pollutes surrounding environment, the hot-air that this patent comes out from dryer is directly sent in the incinerator combustion air as waste incineration and is not polluted the environment and also do not reduce the drying capacity of dryer simultaneously, is the improvement of a last method.Ordering about the mechanical power that rubbish moves in rotating cylinder in addition is little far beyond other oven dry mechanical types also, so bigger superiority is arranged economically.

Waste heat with waste incineration is dried moist rubbish in advance outside incinerator, this just can make rubbish enter in the incinerator with oven-dried condition, thereby significantly reduced the time of rubbish pre-heating temperature elevation in incinerator, and the furnace air coefficient of excess is reduced, the speed that this has just improved the furnace temperature level in the incinerator significantly and burnt away the refuse.Working space in the incinerator also can use the burning of what rubbish to need more fully simultaneously.

Contain a large amount of heat energy in rubbish in burning process always the form with high-temperature flue gas bring to outside the stove.The present invention makes flue gas add hot-air by preheater earlier, and the air after the preheating makes the rubbish oven dry with the rubbish direct contact heat transfer in the oven dry rotating cylinder, and the diabatic process thermal resistance is less, and equipment is simple, is easy to control all advantages.

(1): " garbage problem of opinion Chinese city " Cai Jiancheng, work such as Li Guozhen, publishing house of China University of Geosciences.

(2): " metallurgical furnace thermal basis " Liu Renda chief editor, metallurgical industry publishing house publishes.

Claims

Combustion air is sent in the preheater that is arranged in the incinerator flue with air-introduced machine, the hot flue gas that utilizes waste incineration to produce adds hot-air, air behind the pre-heating temperature elevation enters in the dryer rotating cylinder, directly contacting with oven dry rubbish with the moist rubbish that after the lifting of rotating cylinder inwall, is scattered. the foul smell that produces in the oven dry rubbish process then together enters in the incinerator along pipeline with the combustion air after the cooling, thoroughly burns the method for cinder in the waste incineration process.