SU927848A1 - Apparatus for automatically controlling pyrolysis of gasoil and ethane in tubular furnace - Google Patents

Description

The invention relates to devices for the automatic control of the pyrolysis of petroleum fractions in the presence of initiating additives, such as products of thermal decomposition of ethane, and can be used in the production of olefirs in the chemical and petrochemical industries.

A device for automatically controlling the pyrolysis process is known, comprising a pyrogas composition sensor, a furnace fuel flow controller, summation, multiplication and optimization units 11.

A device is also known to automatically control the pyrolysis of gasoline and ethane in a tube furnace containing coils for heating gasoline, pre-pyrolizing ethane and co-pyrolysis of gasoline and ethane, consisting of a series-connected sensor and a pyrogas temperature controller at the output of the plug and valve on the line filing

fuel to the furnace, gasoline consumption sensor to the furnace connected to the first input of the pyrogas temperature setpoint at the furnace output, the output of which is connected to the second input of the temperature controller, pyrogas composition sensor connected to the first input of the optimization unit, sensor and regulator ethane consumption, the output of which is connected to the valve on the ethane supply line t2.

The disadvantage of the devices is the impossibility of their use. For automatic control of the process,

IS where gasoline and ethane are prepared in different coils of the same furnace for further pyrolysis.

These devices do not count.

G) a set of limitations on the heat output of the furnace, imposed by the heat resistance of the materials in the furnace, and the possibilities of the heat sources. All this leads to a decrease in furnace performance. The purpose of the invention is to increase the productivity of the furnace. The goal is achieved by the fact that the device additionally contains temperature sensors in the furnace and at the coil outlet of the preliminary pyrolysis of ethane, a pressure sensor at the outlet of the temperature regulator connected to the second input of the temperature setting unit, the third input of which is connected to the temperature sensor in the furnace, the second and third the inputs of the optimization unit are connected, respectively, with gasoline and ethane flow sensors to the furnace, the temperature sensor at the output of the ethane pre-pyrolysis coil is connected to the fourth input of the unit optimization, connected by its output with an ethane consumption control knob. The drawing shows the proposed device. The device contains a sensor 1 and a pyrogas temperature regulator 2 at the outlet of the furnace connected to valve 3 on the fuel supply line to the furnace, sensor t and controller 5. Ethane consumption connected to valve 6 on the ethane feed line, sensor 7 pressure at the outlet of the temperature controller 2, the temperature sensor in the firebox and the gasoline consumption sensor 9 connected to the pyrogas temperature setting unit 1 at the furnace exit. The device also contains an optimization unit 11, to the inputs of which a temperature sensor 12 is connected at the output of an ethane pre-pyrolysis coil, a pyrogas composition sensor 13. The device works as follows. In block 10, based on the information received from the sensor 7 3 and 9, the task for controller 2 of the temperature is calculated according to the law For P, Prndx – r – j. “- t () iLv А- where R.P. is the measured and maximum allowable pressure on the fuel gas supply valve; measured and maximum H max but the temperature in the firebox is acceptable; the measured value of the temperature at the furnace exit; K - regulation coefficient, chosen experimentally within 6 - calculated temperature value. about kr. B - coefficient, set depending on the properties of the raw material within 700-750; K - coefficient specified in g limits 0,01-0,05; F - gasoline consumption in the oven, kg / h. Pu R / P max + K (Рто (х-Р) -г т. f. + K (T, ax-f) max. The calculated temperature value dd is maintained by a recirculation circuit consisting of sensor 1, l 2 of the valve and block 3 11, based on the information of the sensors k, 9, 12 and 13, the task for the regulator 5 of ethane is disaggregated by the formula A. (,) (t | -Te), T, T ... is the measured value of the output temperature of the preliminary coil ethane pyrolysis at the current and previous measurement moment; K - regulation coefficient; L ,, A | .-, - ethylene concentration in gasoline pyrolysis products A АИЭМ + Р / Р (АИММ-Э). ethylene concentration value F, k - ethane and gasoline consumption in the furnace; 3 - ethylene concentration in pyrogas, obtained from ethane using average experimental data - 50% of the control loop, sensor, torus 5 and valve 6; scaling by the expression: (t | aA-t) as such, when the device is turned on, control of the temperature at the outlet of the furnace is provided, the limit is. possibility of changing the composition of the pyrogas depending

from the current situation, as well as optimal conversion of ethane in the preliminary pyrolysis coil with full use of the thermal resources of the furnace.

The introduction of this device into industry in accordance with experimental data {|| mi allows you to increase the production of main commodity products by an average of 5 0% relative.

Claims (2)

1. USSR author's certificate number 385997, cl. From 10Q 9/20, 1973. 2. USSR Author's Certificate 30 No. 5E0329, cl. From 10Q to 9/20, 1975.