Ammonia compressor starting method with reduced ammonia consumption

Abstract

The invention discloses an ammonia compressor starting method with reduced ammonia consumption, which includes the following steps: (1) starting; (2) confirming and preparing; (3) starting the set and warming the machine at a low speed; (4) after the warming machine at a low speed is qualified, closing a three-segment outlet emptying valve, and controlling the process gas system pressure by a refrigeration system, and using nitrogen in a ammonia spraying valve displacement process system; (5) when the inlet temperature is reduced to 0-15 DEG C. and the control system pressure is lower than 0.5 MPa, and the ammonia compressor set is beyond the critical valve, controlling the compressor process system pressure by a refrigeration system emptying valve and a side valve; (6) ending. The invention has the beneficial effects that the steps and operations for starting are optimized, thereby realizing that the ammonia compressor is replaced after passing the critical valve instead of before, and substantially shortening the emptying time of gas ammonia, and greatly reducing ammonia consumption and saving production cost.

Description

technical field [0001] The invention relates to an ammonia compressor start-up method for reducing ammonia consumption, and belongs to the technical field of synthetic ammonia production. Background technique [0002] The ammonia compressor is the core equipment in the ammonia synthesis unit, which mainly provides cooling capacity for the ammonia synthesis, air separation and low-temperature methanol washing units. The ammonia compressor and refrigeration system are closed systems. During the normal operation of the device, the system has no vent loss and the ammonia consumption is almost zero. [0003] However, during the start-up process of the unit, the system must replace the nitrogen in the compressor process system with ammonia, resulting in a large amount of ammonia loss and increasing the start-up cost of the compressor unit. Before the ammonia compressor is started, the system is pure nitrogen. In order to ensure that the unit passes the critical speed safely and s...

AI Technical Summary

Problems solved by technology

[0003] However, during the start-up process of the unit, the system must replace the nitrogen in the compressor process system with ammonia, resulting in a large amount of ammonia loss and increasing the start-up cost of the compressor unit

Before the ammonia compressor starts, the system is pure nitrogen. In order to ensure that the unit passes the critical speed safely and stably, it is very important to control the gas composition and pressure. Therefore, before the unit passes the critical speed, the refrigeration system must be opened to replace the process gas system of the compressor with ammonia. It will lead to a large amount of ammonia loss, about 26-30 tons of ammonia loss per start-up, which greatly increases the start-up cost of the ammonia compressor unit

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