Skid-mounted bradenhead gas three-tower separation and recycling device and method

Abstract

The invention relates to a skid-mounted bradenhead gas three-tower separation and recycling device and method. The device in the invention comprises a methane and ethane rectification tower, a propane rectification tower and a heavy component rectification tower which are connected mutually, wherein the methane and ethane rectification tower is used to receive the gas component of the bradenhead gas after desulfurization purification and compression refrigerating, dry gas of which purity is at least 95% can be obtained from the top of the methane and ethane rectification tower; the material discharged from the bottom of the methane and ethane rectification tower is introduced in the propane rectification tower; propane of which purity is at least 90% can be obtained from the top of the propane rectification tower, the material discharged from the bottom of the propane rectification tower is introduced in the heavy component rectification tower; and butane of which purity is at least 90% can be obtained from the top of the heavy component rectification tower, and light oil of which purity is at least 90% can be obtained from the bottom of the heavy component rectification tower. Based on the different components and contents of the bradenhead gas, the liquid nitrogen low temperature rectification method is adopted for separation and recycling, thus the entire device is skid-mounted, the separation and recycling efficiency is higher and four types of products, namely dry gas (methane and ethane), liquefied gas (propane and butane) and light oil (C5<+>) can be obtained finally.

Description

technical field [0001] The invention relates to a wellhead gas separation and recovery device and method, more specifically, to a skid-mounted wellhead gas three-tower separation and recovery device and method. Background technique [0002] Wellhead gas mainly refers to associated gas at small stations, remote wells, and scattered low-yield gas wells in remote areas that are not suitable for building gas pipelines, and also includes flare gas at oil and gas gathering and processing stations. Due to the development difficulties such as low output and rapid pressure drop, this part of wellhead gas is exploited by conventional natural gas treatment technology, and the project investment and operation costs are high, which is uneconomical. [0003] At present, wellhead gas recovery is an economical and environmentally friendly technology, and its marketization process is accelerating. Various scientific research institutes and companies have also developed different processes. I...

AI Technical Summary

Problems solved by technology

The recovery of natural gas or associated gas carried out in many domestic oil fields is mainly for the recovery of liquid hydrocarbons, namely LPG, and the average recovery rate of propane is less than 60%.

At present, it is very difficult to achieve high-efficiency separation and recovery of wellhead gas on skid-mounted devices in China.

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