Closed cycle inert gas spray drying project

  Project Overview

Closed cycle inert gas spray drying project - closed cycle air flow spray drying unit consists of nitrogen closed cycle system, air flow spray dryer, solid gas separation, nitrogen back blowing dust removal, condensation cooling solvent recovery, steam 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 air flow spray drying technology, that is, the liquid (solid content is 50%) material is in the drying process, and the liquid material is transported by the peristaltic pump to the air flow spray gun set in the drying tower (the spray gun can be set with 3-7 nozzles as required by the production capacity) to atomize into droplets. The spray gun is in convection contact with the heat transfer gas from top to bottom from bottom to conduct heat transfer and heat exchange, so as to achieve the purpose of moisture drying in an instant. The finished product is collected at the bottom of the drying tower, and the superheated gas is discharged through a circulating fan below the drying tower and separated by a solid gas separator. The fine powder material carried in the overheated air settles at the bottom of the solid gas separator through the cutting cyclone effect. The superheated 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 3 ℃). 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 of industrial 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, the 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 0.9% (v/v), the oxygen measuring 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 system is designed for positive pressure, and oxygen enters the circulation system through the feeding process). When the air pressure value in the system exceeds the set value (the pressure balance value of the circulation system is set to 0.02mPa), 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 there is a fault in the electrical or critical parts of the system, the normal operation of the system will fail, and the air pressure will rise to the safety limit value (the designed pressure resistance value of the system is less than or equal to 0.05Mpa). The explosion-proof explosion relief device (composed of explosion-proof membrane, explosion guide valve and explosion relief element) will automatically open the directional explosion and automatically cut off the power supply, close the inlet and outlet pipeline valves, and maximize the avoidance of personal injury and property loss. Ensure production safety.

Technical process (flowchart): Call to discuss in detail.

  
Advantages reflected

1) This unit uses nitrogen as the conductive heat transfer medium and nitrogen as the carrier to achieve closed-loop circulation in a closed state, effectively ensuring the safety of drying liquid materials containing organic solvents and protecting the oxidation resistance of easily oxidizable wet materials during the drying production process.

2) The unit adopts air flow spray drying technology, so as to achieve the high solid content that traditional centrifugal spray drying can not compare with, and has viscous and thick liquid material nitrogen power atomization, so as to improve production capacity and reduce energy consumption by more than 70%, achieving significant energy saving and high-yield production effect.

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.

Note: Currently, this project has applied for one invention patent and two utility model patents.