In the vegetable oil refining and deodorization process, a thermal medium is required to ultimately heat the decolorized oil to 240-265°C, and remove volatile components such as free fatty acids from the oil by distillation under high vacuum. The thermal fluid in the process is generally generated by a thermal oil furnace or a high-pressure steam boiler. High-pressure steam boiler, also known as natural circulation steam boiler, has the advantages of high degree of automation, low energy consumption, etc., because of the use of treated soft water as a heat medium, recycling, safe and harmless, has been widely used in oil processing plants, in recent years, the new refining process is almost entirely using high-pressure steam as a heating medium (using diesel or / and natural gas as a heating source).

I. Working principle of high pressure boiler

Appropriate amount of heat medium water to meet the requirements of the high-pressure pump into the boiler system, the heat generated by the combustion system into the boiler body, and the water in the heat transfer pipeline for heat transfer to produce high-pressure steam, high-pressure steam through the pipeline into the heat transfer equipment, and the oil to be deodorized to enter the heat exchange, the condensate through the pipeline back to the boiler body piping, and then evaporation, heat transfer, condensation cycle. The system is operated by a control system that automatically controls the relevant temperature, pressure, etc. according to the data that has been entered, so that the system operates automatically within the specified safety range. Boiler system is also equipped with multiple safety protection from the program, mechanical and other aspects, if the system overpressure and other anomalies, the control system will automatically shut down the burner, the system overpressure reaches the set value of the safety valve will also jump to protect.

Second, the basic structure of the high-pressure boiler

There are three main components: burner, furnace and control cabinet. Burner includes the following components: combustion cylinder, nozzle, flame stabilizer plate, ignition electrode, solenoid valves 1 and 2, hinged flange, safety solenoid valves, flame sensors, ignition cables, timers, ignition transformer, circuit connection programmable controller, looking glass, oil pump, return pipe, dampers, blower wheels, servomotor, burner motor and so on.

 Third, the operation and use of high-pressure boilers (a well-known brand of high-pressure boilers in Germany as an example)

1. High-pressure boiler start-up preparation

1.1 Read the last time the equipment operating records and shutdown in the maintenance records of the equipment, for this normal drive to help;

1.2 Check all the fasteners and brake parts outside this equipment and make them conform to the start-up requirements in the equipment manual;

1.3 checking the operating condition of the systems attached to this equipment (diesel feed system on the periphery of the workshop) and adjusting them to the equipment start-up requirements and the requirements of the production process prior to start-up.

2. High-pressure boiler start-up sequence and operating precautions

2.1 After confirming that the equipment can be started normally, send the power supply to the equipment from the workshop operation control panel;

2.2 Turn on the power on the operation control panel, ready to start;

2.3 Click on the startup program key rest emergency stop for startup;

2.4 when the start, the program will automatically alarm prompts, will all alarms are displayed on the indicator lamp, click hooter off key, the prompts will be eliminated, and then click reset boiker key reset;

2.5 After the program starts, check whether the alarm indicator is normal and water level indication etc water level 1 ok and water level 2 ok;

2.6 Select the temperature control system as controlled by cascade temp/pressure;

2.7 Select the damper control program in the first gear, automatic control can be;

2.8 start combustion ignition burner on, selected from the O position to 1 position, combustion start, pay attention to observe the dampers and flame operation;

3. High-pressure boiler normal operation operation precautions;

3.1 Observe the instructions of the panel control system more, pay attention to the set temperature and pressure and the actual value of the

Difference;

3.2 Pay attention to the burner damper opening size, diesel fuel supply;

3.3 Often observe the chimney emissions, whether black smoke.

4. High-pressure boiler shutdown operation precautions

When it is necessary to stop the operation of the equipment, combustion ignition burner on from 1 position to select O position, combustion stops, in standby mode, if a long period of downtime need to turn off the oil inlet valve and return valve and cut off the power supply.

5 Precautions for the operation of high-pressure boilers in case of sudden power failure

Once there is a power failure, the program operation is automatically terminated, the combustion ignition burner on from 1 bit to 0 bit, to be called back to select from 0 bit to 1 bit, combustion start.