Coke ovenlow pressure ammonia valve changing method for preventing gas discharging

Abstract

The inventionprovides a coke ovenlow pressure ammonia valve changing method for preventing gas discharging. Before changing, the pressure of a gas collecting tube is set to a lower limit of 95-105 Pa; when the temperature of the gas collecting tube is too high so that the pressure surge greatly exceeds an upper limit, a manual operation is performed at the scene; a high pressure ammonia valve with a corresponding oven number is opened with a small open degree of 1 / 5-1 / 4, and high pressure ammonia is temporarily used to replace the low pressure ammonia to cool raw coke oven gas; during the changing process, the opening degree of the high pressure ammonia valve is less than 1 / 4, to ensure the pressure in a coking chamber is higher than the pressure of a combustion system at the same level; after the change is completed, the high pressure ammonia valve is closed in time to prevent the temperature of the gas collecting tube from continuously increasing. The invention can greatly shorten the valve change time, and reduce the raising of the temperature of the gas collecting tube and pressure surge, thereby effectively avoiding environmental pollution caused by coke oven discharging, preventing the pipe fitting of the gas collecting tube from being damaged, and reducing costs for replacement parts.

Description

technical field [0001] The invention belongs to the field of coking, and in particular relates to a method for replacing a low-pressure ammonia water valve of a coke oven for preventing gas from being released. Background technique [0002] The temperature of the raw gas in the gas collecting pipe is generally 80-100°C after being sprayed and cooled by ammonia water. When replacing the low-pressure ammonia water valve, only a certain section of the gas collecting pipe can be stopped. Due to the long operation time, the temperature of the gas collecting pipe can rise to 400 ℃, from the gas state equation PV / T=K (K is a constant), it can be known that when the gas temperature T changes, the volume of the gas begins to expand freely, and the gas collecting pipe is a rigid closed space, and the volume V of the gas collecting pipe is fixed. The increase of the temperature T of the raw gas directly leads to the increase of the pressure P of the gas collecting pipe, which locally i...

AI Technical Summary

Problems solved by technology

[0002] The temperature of the raw gas in the gas collecting pipe is generally 80-100°C after being sprayed and cooled by ammonia water. When replacing the low-pressure ammonia water valve, only a certain section of the gas collecting pipe can be stopped. Due to the long operation time, the temperature of the gas collecting pipe can rise to 400 ℃, from the gas state equation PV / T=K (K is a constant), it can be known that when the gas temperature T changes, the volume of the gas begins to expand freely, and the gas collecting pipe is a rigid closed space, and the volume V of the gas collecting pipe is fixed. The increase of the temperature T of the raw gas will directly lead to the increase of the pressure P of the gas collecting pipe, which will locally increase the pressure of the raw gas in this section, resulting in uneven pressure distribution inside the entire gas collecting pipe.

When the automatic regulator is adjusting, the pressure in the gas collection pipe changes greatly, and the gas collection pipe is prone to release due to untimely adjustment, and a large amount of raw gas escapes, causing serious environmental pollution

In addition, the air collecting pipe and fittings may crack due to temperature rise