Navigation documents:
1. Overview
Nitrogen circulation spray dryer is a special equipment for preparing bio pesticide, bio medicine, powder metallurgy, lithium battery materials, tungsten carbide, precision ceramics and other powders. The system adopts explosion-proof design and nitrogen circulation, making equipment operation safer. The product is non oxidizing, of good quality, and has good biological activity protection. The loose packing density and average particle size of the powder are consistent, and its flowability can meet the continuous production of automatic presses. At the same time, the organic medium can be recycled. The entire equipment consists of a feeding system, high-speed centrifugal atomizer, explosion-proof electric heater, air supply fan, drying tower, cyclone dust collector, bag filter, exhaust fan, condensing tower, chiller unit, and electrical control system. The drying unit produced by our company has been put into use by multiple manufacturers.
Inert gas circulation spray drying project - nitrogen circulation spray drying unit consists of nitrogen closed circulation system, centrifugal spray dryer, solid gas separation, nitrogen back blowing dust removal, condensation cooling solvent recovery, electric heating and other main parts.
Using nitrogen as the conductive heat transfer medium, it achieves the drying production of organic solvent suspensions, viscous and viscous liquid materials, and the recovery of organic solvents in the fields of pharmaceuticals, biochemistry, chemical engineering, biology and other technologies, with practicality of low consumption, energy saving and emission reduction. The unit adopts the closed circulation technology, with nitrogen as the conduction heat transfer medium. While the liquid material containing organic solvent is dried and produced, the solvent is recycled by the condensation cooling technology. In order to improve the drying intensity and drying production capacity of the unit, the unit adopts the centrifugal spray drying technology. The liquid material is delivered by the feed pump to the centrifugal atomizer set in the drying tower for atomization into droplets, which is in parallel flow with the heat transfer gas from top to bottom for heat transfer and heat exchange. The purpose of moisture drying can be achieved instantly. The finished product is collected at the bottom of the drying tower, and the superheated gas is extracted by a circulating fan below the drying tower and separated by a solid gas separator. The fine powder material carried in the circulating gas settles at the bottom of the solid gas separator through the cyclone action. The circulating gas passes through the nitrogen backwash dust collector twice to capture the dust material carried in the gas. The waste heat gas enters the condenser and is cooled by the condenser cooling medium (with a condensation temperature of 5 ℃). Condense to dew point to achieve the recovery of organic solvents. The circulation system is supplemented with nitrogen to achieve a new round of closed-loop nitrogen circulation for continuous drying production, thus meeting the process requirements for industrial continuous production in the relevant industries mentioned above.
Based on the explosive and flammable safety hazards of organic solvents, this unit system adopts online oxygen measurement, overpressure relief, explosion prevention, and other safety technology measures. Through intelligent control technology, online monitoring of residual oxygen in the system, pressure balance monitoring, and automatic adjustment control are achieved. When the air (oxygen) leakage rate in the system exceeds the specified limit, the online oxygen measurement device will command the nitrogen replenishment valve to open through the control system, replenishing fresh nitrogen into the system to restore the residual oxygen level to the safe set value range (the closed-loop circulation system is designed for positive pressure, and oxygen enters the circulation system through processes such as feeding). When the air pressure value in the system exceeds the set value, the pressure relief device will automatically open the pressure relief pneumatic valve through the intelligent control center command to eliminate the overpressure gas. The explosion-proof explosion relief device is another safety technical measure adopted by this unit, which means that if the electrical or critical parts of the system fail, the normal operation of the system will malfunction, and the air pressure will rise to the safe limit value. The explosion-proof explosion relief device will automatically open the directional explosion and cut off the power supply, close the inlet and outlet pipeline valves, and maximize the avoidance of personnel injury and property damage, ensuring production safety.
Advantages reflected:
1) This unit uses nitrogen as the conductive heat transfer medium and nitrogen as the carrier to achieve closed-loop circulation of nitrogen in a closed state, effectively ensuring the safety of drying liquid materials containing organic solvents and protecting the oxidation resistance and activity of easily oxidizable wet materials and biologically active materials during the drying production process.
2) The unit adopts centrifugal spray drying technology, which can atomize viscous and thick liquid materials, so as to improve production capacity and reduce energy consumption, and achieve the production effect of energy conservation and high yield.
3) This unit adopts online monitoring and self diagnostic control functions to ensure safe production of liquid materials containing organic solvents during drying. The intelligent control system has a high degree of automation.
4) This unit realizes the recycling and utilization of materials containing organic solvents in the drying production process, and on the basis of solving the difficulties in drying and heavy pollution caused by exhaust gas emissions in related industries, achieves the practical effect of energy conservation and emission reduction through solvent recycling and utilization.
2. Design basic data
2.1. Drying materials: biological pesticides (the slurry process buyer is responsible for meeting the spray drying conditions)
2.2. Solvent composition: Alcohol (or other solvent components)
2.3 Circulating gas: Nitrogen protection (user provided)
2.4. Solvent evaporation rate: 3~5kg/h
2.5. Solid content of slurry: 20-35% (meeting atomization and conveying requirements) (designed at 25%)
2.6. Slurry pH Value: Neutral
2.7. Slurry temperature: room temperature
2.8. Inlet air temperature of drying tower: 110-120 ℃ (adjustable temperature, designed at 120 ℃)
2.9. Drying tower outlet temperature: 60-65 ℃ (adjustable temperature, designed at 65 ℃)
2.10 Alcohol recovery rate: ≥92%
2.11 Tower dwell time: 12 seconds
2.12. Residual moisture content of the product: ≤0.8%
2.13. Power supply: three-phase five wire system, 380/220V, 50Hz
2.14. Heating method: Explosion proof electric heating box
2.15. Atomization method: High speed centrifugal atomization (8000~20000r/min)
2.16. Material receiving method: Main tower receiving
2.17. Dust removal method: cyclone+pulse bag filter for dust removal
2.18. Solvent recovery method: alcohol collection tower recovery
3. Equipment performance parameters
3.1. Average heat consumption: about 6000Kcal/h
3.2. Electric heating power: 18kw (automatic temperature control)
3.3. Mechanical power: approximately 9Kw
3.4. Flow rate of feed pump: 22L/h
3.5. Unit pressure range: −3000~3000Pa
3.6. Condenser tower outlet temperature ≤ 18 ℃
3.7. Oxygen content in the tower ≤ 3%
3.8. Solvent recovery rate: ≥90%
3.9. Bag filter area: 1.5m²
3.10. Chiller power: 5.5kw
3.11. Installing sound insulation devices: reducing noise
3.12. Drying tower size (inner tank size): Φ1600×1320×60°
3.13. Tower floor area: (length x width x height) 4.5m x 2.8m x 5.2m (factory height)
3.14. Size of electrical control cabinet: (height x width x thickness) 2m x 1m x 0.5m (placed in non explosion proof area)
4. Requirements for shared facilities
Users should have facilities such as water, electricity, gas, and factory buildings
4.1. Installed capacity: 27kw (including electric heating power, mechanical power, and chiller power)
4.2 Power supply: 380/220V 50HZ three-phase five wire lead to the bottom of the electrical control cabinet
4.3 Nitrogen: Used for supplementing nitrogen in the main circulation system of the drying tower, with a pressure of 0-0.3Mpa and a consumption of 1Nm³/h. Purity 99.9%.
Used for nitrogen filling after cleaning the drying tower, with a pressure of 0-0.3Mpa and a consumption of 8Nm³/h. Purity 99.9%.
Used for pulse blowback of bag filter, pressure 0.45-0.55Mpa, consumption 2.5Nm³/h. Purity 99.9%.
DN15 pipe with ball valve, pressure regulating valve leads to designated point. Nitrogen generators or bottled nitrogen can be used.
4.4 Compressed air: oil and water removed, pressure 0.5-0.7Mpa, consumption 0.2m³/Min, DN15 pipe with ball valve, pressure regulating valve leads to designated point.
5. Supply boundary area and supply list
Supply boundary area:
From the inlet of the feed pump to the outlet of the cyclone separator and bag filter
Add nitrogen from the intake port to the gas consumption point, and exhaust from the exhaust port to the outlet of the breathing valve
Compressed air: from the air storage bag of the dryer to each gas consumption point
Power supply: from the control cabinet to various power and signal points of the unit
Tap water: from the drying tower platform column to each water consumption point
Solvent: from the outlet of the alcohol collection tower storage tank