Working principle: The garbage enters the inclined downward grate through the feed hopper (the grate is divided into a drying area, a combustion area, and a burn-out area). Due to the interlaced movement between the grate, the garbage is pushed down and the garbage passes through in turn Various areas on the grate (when garbage enters from one area to another, it acts as a large turn) until it is burned out of the furnace.
The combustion air enters from the lower part of the grate and mixes with the garbage; the high-temperature flue gas generates hot steam through the heated surface of the boiler, and the flue gas is also cooled. Finally, the flue gas is discharged after being processed by the flue gas treatment device.
Features: The grate furnace domestic garbage incineration technology is stable in operation, has a strong ability to treat garbage thoroughly, and is suitable for continuous operation. After optimized flue gas treatment technology, the emission reaches the standard.
However, the material requirements and processing accuracy requirements of the grate are high, requiring that the contact surface between the grate and the grate is relatively smooth, and the gap between the rows is relatively small. In addition, the mechanical structure is complex, the damage rate is high, and the amount of maintenance is large.
2. Fluidized bed incinerator
Working principle: The furnace body is composed of a porous distribution plate. A large amount of quartz sand is added into the furnace chamber, the quartz sand is heated to above 600 ℃, and hot air above 200 ℃ is blown into the bottom of the furnace to make the hot sand boil, and then put in Rubbish.
Rubbish boils with hot sand, and the rubbish is quickly dried, caught on fire, and burned. The proportion of unburned garbage is lighter and continues to boil. The proportion of burned garbage falls to the bottom of the furnace. After water cooling, the coarse and fine slag are sent to the outside of the plant with a sorting equipment. A small amount of medium slag and The quartz sand is sent back to the furnace through the lifting equipment to continue to use.
Features: The fluidized bed is fully combusted and the combustion control in the furnace is good, but the amount of dust in the flue gas is large, the operation is complicated, the operating cost is high, the uniformity of the fuel particle size is high, and a high-power crushing device is required. The equipment is badly worn and the equipment maintenance is heavy. It is easy to cause coking, and the system's continuous operation ability is low.
3. Rotary incinerator
Working principle: The rotary incinerator is arranged with cooling water pipes or refractory materials along the furnace body, and the furnace body is placed horizontally and slightly inclined. Through the non-stop operation of the furnace body, the garbage in the furnace body is fully burned, and at the same time, it moves in the inclined direction of the furnace body until it is burned out and discharged from the furnace body.
Features: High equipment utilization, low carbon content in ash, low excess air, and low harmful gas emissions. But the combustion is not easy to control, and it is difficult to burn when the calorific value of garbage is low.
4. CAO incinerator
Working principle: The garbage is transported to the storage tank, enters the biochemical treatment tank, and dehydrated under the action of microorganisms, so that natural organic matter (kitchen waste, leaves, grass automatic garbage power generation crane, automatic garbage power generation crane, etc.) is decomposed into powder, other solids Synthetic organic matter including plastics and rubber and inorganic matter in the garbage cannot be decomposed and pulverized.
After screening, the unpulverized waste enters the first combustion chamber (temperature is 600 ℃) before entering the incinerator, and the combustible gas produced enters the second combustion chamber. The non-combustible and non-pyrolyzable components appear as ash The shape is discharged in the first combustion chamber.
The temperature in the second chamber is controlled at 860 ° C for combustion, and high-temperature flue gas heats the boiler to produce steam. The flue gas is discharged from the chimney to the atmosphere after treatment. The metal glass will not be oxidized or melted in the first combustion chamber and can be sorted and recovered in the ash.
Features: Recyclable useful materials in the garbage; but the processing capacity of a single incinerator is small and the processing time is long. At present, the daily processing capacity of a single furnace is up to 150 tons. Because the residence time of flue gas above 850 ℃ is difficult to exceed 1 second The clock is short, and the content of dioxins in the smoke is high, making it difficult to meet the environmental protection standards.
5. Pulse toss
Working principle: The garbage is sent to the drying bed of the incinerator through an automatic feeding unit for drying, and then sent to the first-stage grate. After high-temperature volatilization and cracking on the grate, the grate is thrown by the impulse aerodynamic device The garbage is thrown into the next level grate step by step, at this time the polymer material is cracked and other materials are burned.
In this way, it will enter the ash slag pool after being burned out at the end, and be discharged by the automatic slag removal device. Combustion-supporting air is injected into the air holes on the grate and mixed with the garbage to burn while suspending the garbage in the air. The volatilized and cracked substances enter the second-stage combustion chamber for further cracking and combustion. The unburned flue gas enters the third-stage combustion chamber for complete combustion; the high-temperature flue gas heats the steam through the boiler heating surface, and the flue gas passes Discharge after cooling.
The advantages are:
(1) A wide range of waste disposal, capable of processing industrial waste, domestic waste, hospital waste, waste rubber tires, etc .;
(2) The combustion thermal efficiency is high, the normal combustion thermal efficiency is more than 80%, even if the domestic waste with large water content, the combustion thermal efficiency is more than 70%;
(3) Low operation and maintenance costs, due to the use of many special designs and a high level of automation control, there are few operating personnel (only two people are required for a furnace including ash removal personnel), and the maintenance workload is also small (4) High reliability, after nearly 20 years of operation, the failure rate of this incinerator is very low, the annual operation is more than 8000 hours, and the general utilization rate can reach more than 95%;
(5) The level of emission control is high. Due to the use of secondary flue gas burning and advanced flue gas treatment equipment, the flue gas is fully treated;
(6) The grate is purged by compressed air and has a self-cleaning function.