Room Temperature Deoxygenation System

1. Product Introduction

The efficient deoxygenation energy-saving system is centered around hollow fiber membrane contactors, designed to create corresponding energy-saving systems for different working conditions, helping enterprises save energy and reduce carbon emissions, while generating economic and social benefits.

The fiber membrane contactor is a membrane component used for gas-liquid mass transfer, with membrane materials that have the characteristic of "gas-permeable but water-impermeable," allowing the isolation of liquids on both sides while gases can pass freely, forming gas-liquid contact on the surfaces of the material. As shown in Figure 1, water flows outside the membrane fibers, while a vacuum is drawn inside the fibers. Gases such as O2 and CO2 dissolved in water pass through the membrane pores and are drawn away by the vacuum, while water cannot penetrate the membrane pores, resulting in the removal of dissolved gases from the water.

Figure 1: Principle of Deoxygenation by Membrane Fibers

Modern membrane contactor components adopt highly efficient structural designs, as shown in Figure 2, allowing their mass transfer efficiency to exceed that of traditional contact towers (vacuum towers, absorption towers, stripping towers, etc.) by more than 10 times. Therefore, the mass transfer driving force is only 1/10 of that of traditional towers, which means that dissolved gases in water can be removed at a rate 10 times lower than that of towers. In scenarios where the dissolved oxygen requirement in water is very high, such as semiconductor ultra-pure water (dissolved O2 < 1 ppb) and high-pressure boiler make-up water (dissolved O2 < 7 ppb), this system has significant advantages. In addition to excellent deoxygenation performance, the membrane deoxygenator is particularly energy-efficient, with energy consumption only 4% of that of thermal deoxygenators, and total operating costs only 10% of those of thermal deoxygenators. The membrane deoxygenator operates at low temperatures, allowing the deoxygenated water to absorb more low-temperature waste heat from production equipment, resulting in excellent energy-saving benefits.

Structure Diagram of Fiber Membrane Contactor

　　2. Models of Fiber Membrane Contactor Components

ANHONG ENERGY EQUIPMENT (Yangzhou) Co., Ltd. has reached a deep strategic cooperation with Jiangsu Aijike Membrane Technology Co., Ltd. to provide a complete range of membrane component models for the Chinese market, matching different models for various processes, offering "customized" products and engineering designs, and providing integrated operation and maintenance services.

Membrane Component Parameter Table

　　3. Efficient Deoxygenation Energy-Saving System

1. System Schematic Diagram

Process Flow Schematic Diagram

System Skid Schematic Diagram

2. System Parameters

　　4. Case Studies

1. Xuzhou Thermal Power Energy Saving and Carbon Reduction Project

Xuzhou Thermal Power has four gas boilers, covering a heating area of 400㎡. Each gas boiler corresponds to a thermal deoxygenator, consuming part of the steam for deoxygenation. An overall engineering renovation was carried out for this process. A super-low consumption ambient temperature deoxygenation system was bypassed before the desalination water pump in the water treatment workshop, and the thermal deoxygenator was sealed and pressure-controlled along with other process renovations. After the project implementation, 1.26 million m³ of natural gas can be saved in one heating season.

2. Energy Saving Project for Self-Supplied Power Plants in Steel Industry

The No. 2 generator set of the Energy and Environment Department's distribution center is a 350MW subcritical pressure unit, equipped with a thermal deoxygenator of about 1000t/h, with deoxygenation costs reaching 2 million/year. Through investigation, it was found that the proportion of condensate water reached over 95%, and the oxygen content was extremely low, making new water supplementation a key focus for deoxygenation. A super-low consumption ambient temperature deoxygenation system and thermal deoxygenator were added after the make-up water pump for peripheral renovations, replacing the thermal deoxygenator at a very low cost. The annual energy-saving steam volume is about 29,000 tons.

3. Energy Saving Project for High Purity Water in Fine Chemicals

The water treatment system for the project was built in 2021, with a treatment process of tap water - ultrafiltration - reverse osmosis - EDI - deoxygenation membrane, with a treatment capacity of 150 cubic meters/hour, and an outlet oxygen content of ≤15 ppb. The system operates stably, and the outlet meets design requirements. A portion of the system's effluent enters the boiler steam drum as make-up water, while another portion is used as process water, enhancing the product's antioxidant properties and transparency by removing gases and impurities from the water.