Novel heat pump distillation deamination energy-saving process

Abstract

The invention provides a novel heat pump distillation deamination energy-saving process. The process comprises the steps of A, carrying out distillation deamination on ammonia water sent from the outsides of a boundary region in an ammonia distillation tower, sending ammonia distillation wastewater at the bottom of the ammonia distillation tower to a flash tower, and carrying out flash distillation in the flash tower; B, sending flash steam generated by the flash distillation into a compressor, and compressing the flash steam by the compressor to do work; and C, sending steam output by the compressor into the bottom in the ammonia distillation tower, forming rising steam needed by distillation with evaporated ammonia distillation wastewater, transferring mass and heat with an ammonia countercurrent decreased from the upper part of the tower to finish the distillation process, carrying out heat exchange on a part of ammonia distillation wastewater after flash distillation and ammonia-containing steam exhausted from the top part of the ammonia distillation tower, recovering the heat of the ammonia-containing steam, returning the ammonia distillation wastewater to the flash tower, carrying out heat exchange on the rest of the ammonia distillation wastewater after flash distillation and the ammonia water which enters the ammonia distillation tower, recovering the heat, water cooling the ammonia distillation wastewater to 35-45 DEG C, then introducing the wastewater into a treating procedure or an ammonia washing procedure. The novel heat pump distillation deamination energy-saving process is a novel deamination distillation process which is simple in the process flow, little in the investment and high in the energy-saving efficiency of 70 percent.

Description

technical field [0001] The invention relates to the technical field of heat pump distillation, in particular to a new heat pump distillation deammonization energy-saving technology. Background technique [0002] The chemical industry is a large energy consumer, and distillation is a unit operation with extremely high energy consumption. However, the traditional distillation method has low thermodynamic efficiency and a lot of energy waste. For example, in the document "Application of New Ammonia Distillation Process in Shougang Jingtang Project" ("Fuel and Chemical Industry", 2008 (4): 33-35), the ammonia in the solution is separated from the coking ammonia water by distillation, and the ammonia water needs to consume ~ 175Kg0.6MPa saturated water vapor. [0003] In today's situation of rising energy prices, how to reduce the energy consumption of the ammonia distillation tower and make full use of low-temperature heat sources has become a common concern. Many energy-savin...

AI Technical Summary

Problems solved by technology

[0005] 1. High investment, complex process flow, high-concentration toxic and harmful media are directly compressed by compressors, the compressors are severely corroded or require high material grades, and insufficient heat recovery;

[0006] 2. The compressed gas contains non-condensable gas, which leads to low heat transfer efficiency of the reboiler, high operating pressure of the reboiler, and easy corrosion;

[0007] For example, if coking ammonia water distillation uses any process in the above literature, there will be problems such as serious corrosion or high material grade requirements, blockage, complicated process, and insufficient heat recovery.

[0008] 2010101232510, titled "Heat Pump Flash Steam Stripping and Removal of Ammonia", and 2012101536708, titled "A Treatment Method for High-Concentration Ammonia-Containing Wastewater Based on Vapor Compression", both of which require the use of a reboiler, the process The process is complicated, and there are still problems that the compressor is in contact with high-concentration ammonia gas, severe corrosion, or high material grade requirements

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