The 60t/d Hazardous Waste Incinerator Project of Jiangxi Brothers Pharmaceutical Co., Ltd.

Engineering design conditions

The actual solid-liquid ratio of the waste is about 1:1, the processing capacity is about 18,000 tons each year, the comprehensive calorific value is considered between 3500kcal/kg and 4000kcal/kg, the daily processing capacity is 60t every day, and the overload capacity is 20%.

Note: This incinerator shall not be used for incineration and treatment of waste with flame retardant substances, high halide and high salt content.

Main equipment parameters

Requirements for the technical indicators of the incinerator

• 
  Incinerator type: rotary kiln + secondary combustion chamber

• 
  Temperature of the incinerator (secondary combustion chamber): 1,100℃

• 
  Flue gas residence time: 3.5s

• 
  Efficiency of incineration: 99.9%

• Burning and removal rate: 99.99%

• 
  Thermal reduction rate of incineration residue:＜5%

• 
  Incineration treatment:

1) First, open the air supply fan to purge the residual gas in the furnace and other flammable and explosive gas to prevent the explosion after ignition.

2) Before the burner working, turn on the induced draft fan and purge the furnace for five minutes. Combustion fuel natural gas is transported through pipeline and ignited by ignition burner. The heat of the burner slowly increases the temperature of the rotary kiln and the secondary room.

3) The solid waste is sent into the rotary kiln by the feeding system, and the combustion temperature is controlled at 850℃ by controlling the amount of oxygen supplement.

The waste liquid enters the rotary kiln or the secondary combustion room from the waste liquid pipeline.

4) The flue gas produced by the rotary kiln enters the secondary room, and the ash produced by incineration is automatically discharged by the wet scraper.

5) Incineration of flue gas in the secondary combustion chamber by organic waste liquid further high temperature incineration, the combustion temperature increased to 1100℃, make the incineration more complete, smokeless, odorless, the effect of secondary pollution, flue gas in the secondary room stay time for 3.5 seconds, make the trace organic matter and dioxin decomposition, decomposition efficiency exceeds 99.99%, to ensure that the smoke decomposition of organic composition and carbon particles at the temperature of about 1100℃. Multiple stage combustion in the secondary combustion chamber effectively inhibited the generation of nitrogen oxides.

6) The flue gas from the secondary combustion chamber enters the waste heat steam boiler, and the 10% ammonia is injected into the boiler cavity for high temperature SNCR reduction, removing the NOx in the flue gas, and then the high temperature flue gas and the boiler evaporation tube bundle for heat exchange, and producing saturated steam into the factory pipe network. At the same time, the ash in the flue gas is further settled in the boiler cavity, improving the cleanliness of the flue gas.

7) The flue gas from the boiler enters the semi-dry emergency cooling tower. By pressurized pump, through the top of the double fluid nozzle into the reactor, through the double fluid nozzle atomization into fine fog droplets, atomization fog drops by upward heat smoke, form a fog droplets near the nozzle suspended high density area, by adjusting the injection amount to control the temperature in 1s quickly reduced to about 200℃, thus effectively inhibit the regeneration of dioxin. At the same time, some sparks in the smoke are extinguished by the water spray, to protect the subsequent bag from burning out.

8) Subsequently, the flue gas enters the dry acid removal and dioxin absorption device, and is equipped with a storage tank equipped with carbon lime and activated carbon. The carbon lime and activated carbon are transported by the star ash discharge valve by high pressure wind sweep, and enter the connection flue and incineration exhaust gas reaction to further purify the exhaust gas. The effect of spraying carbon lime is to remove HCl, NOx and other acidic components in the absorbed flue gas, and the effect of activated carbon is to adsorb and remove a small amount of residual pCDDs, PCDFs and so on in the flue gas.

9) The tail gas enters the gas box type bag dust collector to remove the fine dust trapped in the flue gas. The carbon lime and activated carbon mixture sprayed in the dry spray tower enters the bag dust collector and adsorbs on the bag, and the carbon lime and activated carbon not fully reacted adsorption continue to absorb and react. The dust collector is equipped with a bypass flue. When the inlet temperature of the bag dust collector is not within the limit range, the bag bypass solenoid valve opens, and the flue gas enters the chimney from the bypass to ensure that the bag does not cause fatal damage to the bag when the smoke temperature is abnormal.

10) The flue gas from the cloth bag enters the spray tower and the wet filler tower device through the induced draft fan. The main function is to wash away the acid gas in the flue gas.

11) After reaching the standard, the gas enters the wet electric precipitator (reserved) to further dust and particle water droplets of the cooled flue gas.

12) The flue gas generated by the wet electric precipitator (reserved) is heated by the reheater, making the outlet temperature controlled by 160℃ and reaching the SCR denitration temperature.

13) High temperature flue gas enters the SCR to reduce the content of nitrogen oxides under the action of urea gas and catalyst.

14) The high temperature flue gas returns to the reheater (reserved) jacket, exchanges heat with the original low temperature flue gas, and finally discharges through the chimney.