管式加热炉温度控制系统设计与仿真(英文)

英文介绍

Tubular furnace temperature control system

1 plan selected

Tubular furnace is important in the production of oil refining, chemical industry, one of the devices its task is to put the ingredients oil heated to a definite temperature, to ensure that the next working procedure smoothly. Accordingly, often choose materials for oil export temperature controlled parameter, fuel flow control variables, temperature control system, the influence of raw material oil export temperature disturb any materials oil flow, raw material inlet temperature, fuel oil pressure, fuel pressure, etc. This system oil export temperature changes according to the raw material to control valve opening, through fuel change fuel flow will crude oil exports temperature control in the provision of numerical, is a simple control system.

When the fuel pressure or fuel calorific value change, the influence of furnace temperature, then first by the heat transfer process of gradual influence material outlet temperature of oil. From the fuel flow changes after three capacity, just the oil export temperature changes caused by raw materials, the channel, about the time constant big 15min, slow to respond. And temperature regulator is based on raw materials with setting the export of oil temperature control the deviation. When the fuel parts appear disturbance, control system and cannot seasonable generates control effect, overcome interference for the controlled the effects of parameters, control quality is poor. When production process on raw materials when oil export temperature demanding, the simple control system is difficult to meet the requirements.

Fuel burning in hearth furnace, first cause temperature change, again through the chamber and raw materials to temperature will heat the oil, but also among raw oil pipe by raw materials oil pipeline. Obviously, fuel change or fuel calorific value of furnace temperature changes, first make changes. If the accused of parameters of furnace temperature as single loop control system composed, can make the control channel capacity, time constant lagging reduce 3min, about the interference from fuel to the control function of comparative timely. But the problem is of furnace temperature after all cannot truly representative materials, even if oil export temperature of furnace temperature constant, raw material flow or entrance of the oil itself temperature change can still affect raw materials, because the oil export temperature from raw material oil interference and not included in the feedback loop, the control system can't overcome within oil export of raw materials, the control effect is the influence of the temperature of still cannot meet production process requirements. If will above two control system of the advantages - temperature regulator accurate control of controlled parameter of temperature regulator, the interference from the fuel control in time combined, according to the change of furnace temperature, change fuel, to quickly remove the interference from the fuel for the influence of the temperature of furnace; Then according to the raw materials of temperature and oil export value deviation of furnace temperature regulator, change the setting, further regulate fuel to keep raw oil export constant temperature, thus constituted raw materials for the main oil export temperature accused of furnace temperature parameters to control parameters for auxiliary was the cascade control system. Tubular furnace cascade control system in such interference on crude oil exports mainly by