Amino acid-containing condensate steam stripping system and tail gas treatment method

Abstract

The invention discloses an amino acid-containing condensate steam stripping system and a tail gas treatment method for solving the problems of an existing steam stripping system that a treatment method is complex, system energy consumption is high, corrosion to pipe plates and pipelines is serious and equipment investment is high. The method comprises the steps of correspondingly feeding high temperature condensate, medium temperature condensate and low temperature condensate to a high temperature condensate stripping section, a medium temperature condensate stripping section and a low temperature condensate stripping section of a stripping tower, respectively, reducing the temperature of stripping gas at a stripping tower top to be 85-90 DEG C through an overhead condenser, and feeding into an incineration furnace, wherein the high temperature condensate stripping section is provided with a reboiler, low-pressure steam used as a heat source is used for carrying out steam stripping to the condensate, the medium temperature condensate stripping section and the low temperature condensate stripping section adopt high temperature flash gas generated by the high temperature condensate stripping section as the heat source, and low-pressure nitrogen gas is introduced for gas stripping. The process is simple, the operation can be controlled flexibly, the system stability is good, energy is saved, the consumption is reduced, the corrosion of the steam stripping system can be reduced to the maximum extent and the service life of the equipment can be prolonged.

Description

technical field [0001] The invention relates to a condensate stripping process, in particular to a treatment method for stripping an acid-containing condensate and tail gas. Background technique [0002] Acid-containing condensate generally comes from the condensation of process gas. For example, in the modern large-scale coal chemical industry, a large amount of condensate is usually produced in the carbon monoxide shift process. Due to the staged recovery of waste heat, process condensate with different temperature levels is usually produced. This part of the condensate usually contains NH 3 , CO 2 、H 2 Corrosive components such as S, HCN, HCl and COS need to be treated by a condensate stripping device to strip the above corrosive components from the condensate, and the clean process condensate is sent to other devices for reuse. At present, there are two common condensate stripping devices, one is a single-column process, with a separate top condenser and reflux system...

AI Technical Summary

Problems solved by technology

The invention proposes to set different levels of flash systems to reduce the possibility of ammonium salt crystallization, and focuses on solving the environmental protection problems caused by system pipe blockage and system overpressure venting, but there are high stripping steam consumption and two tail gases need to be treated separately , the process is relatively complicated, and it does not fundamentally solve the problem of NH 3 , CO 2 、H 2 The high-concentration acid gas low-temperature condensate formed by S together will cause corrosion to equipment and pipelines, and at the same time, due to the high concentration of NH at the bottom of the flash tank 3 , CO 2 、H 2 Liquids such as S, according to current engineering experience, will cause serious corrosion to the bottom of the flash tank and the heat exchange tubes of the top condenser, and in the invention, the flash steam goes directly to the flare header, and there is still a small amount of NH 4 HS, NH 4 HCO 3 Accumulated in the pipeline for a long time, thus blocking the torch tube and causing safety accidents

Invention patent CN 101570350A "A stripping method for process condensate in CO shift" proposes the use of double-tower stripping to separate CO 2 and NH 3 Carry out stripping, focusing on solving the problem of ammonium salt crystallization blockage in the stripping system, but there are problems such as large coupling between the two-stage stripping system, fewer control and adjustment measures, and unstable operation, and the acid gas in this patent is still There is a lot of H 2 O, NH 3 , CO 2 、H 2 S, after the acid gas passes through the carbon dioxide stripping tower condenser, due to the low temperature, condensate will condense out, and the chemical corrosion here is very serious

Generally, it must be stopped for maintenance within 1-2 months, which seriously affects the continuous operation of the whole plant

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