Consumption measures U-zinc steam condenser back to the distillation tower 1 Introduction Hard zinc is precipitated Fe5Zn2i, FeZ> 8 and other paste-like crystals precipitated during crude zinc smelting process. During the hard zinc refining process, impurity metals such as As, Ge, and C are precipitated together with hard zinc, and at the same time, the valuable metals of gallium and indium contained in the crude zinc are enriched. The Shaoguan smelter uses vacuum to treat hard zinc and recovers zinc from hard zinc and valuable metals such as gallium and indium.

2 Hard Zinc Vacuum Distillation Production Process The basic principle of hard zinc vacuum distillation: multi-impurity coarse metal or multi-element alloy. After the temperature is raised, the element with large vapor pressure will volatilize preferentially, leaving the metal with low vapor pressure, and When the temperature is the same, reducing the pressure of the system can greatly increase the volatilization rate of the metal.

For the production process.

Recovery of Indium) Recovery of Gallium, Indium) Vacuum Furnace Treatment of Hard Zinc Rich Zinc, Indium, and Gallium Production Processes 3 Production Energy Consumption Analysis and Energy Savings During the vacuum distillation of hard zinc production, a large amount of energy is consumed. Table 1 shows the proportion of energy costs consumed in the production of vacuum furnaces in our factory.

Energy consumption type Electro-graphite electrode Vacuum oil gas Water Nitrogen Other total consumption ratio A) As can be seen from Table 1, the consumption of electricity, graphite electrode, vacuum oil, and gas accounted for 97.24% of the energy consumption of the vacuum furnace production. Improve the vacuum furnace magnetic regulator Running power factor and reducing power consumption The magnetic regulator is one of the important equipments in the vacuum distillation hard zinc production system. It supplies the low voltage and high current power supply. The graphite electrode load can be smoothly and steplessly adjusted to make the furnace The temperature required to reach the process. After testing, the power factor of the magnetic voltage regulator is lower than that of the table, resulting in a large line current and heat loss, and a large vacuum furnace reactive power, resulting in power loss and other issues.

Table 2 Magnetic Regulator Power Factor Vacuum Furnace No. The power factor is to increase the power factor of the vacuum furnace. Through the calculation and analysis of the test, a capacitive on-site compensation method is used. An additional 200 kvar of low voltage is provided at the input of the magnetic regulator. The power factor compensator is compensated on-site to increase the power factor of the vacuum furnace and reduce the power loss. See Table 3).

Table 3 Before and after capacitance compensation Vacuum furnace current, power factor comparison Before the current compensation of the furnace number Before the compensation of the power factor compensation After the vacuum furnace uses capacitance compensation, the power factor of the vacuum furnace is increased, and the energy can be saved by 160 MWh. 2) Inhibiting graphite The oxidation of the electrode reduces the graphite consumption. Graphite is easily oxidized by air, water, and carbonic acid gas C2) to produce CO or CO2 at high temperatures. It is easy to escape and cannot form a dense oxide film protective layer on some metal surfaces. It is continuous. The coating method and impregnation method are the main methods for inhibiting oxidation, and the more commonly used methods are silicon carbide coatings and phosphate impregnation to prevent oxidation. In the practical application of vacuum furnaces, due to the temperature fluctuations of the electrodes during feeding and discharging, the silicon carbide coating and the graphite substrate are only physically combined and the adhesion is poor. The thermal expansion coefficients of the two are different, and the coating is easily peeled off. The effect is not ideal. In practical applications, the graphite electrode is impregnated with phosphate and the effect of inhibiting oxidation is obvious.

The installation of graphite electrodes requires good contact between the electrode assemblies, the selection of cold and heat sources for energy-saving central heating (cold) (China Municipal Engineering Research Institute, North China Design and Research Institute, Tianjin 300074, China). Lu Dehong Lin Chengfang's program features and puts forward suggestions for selection.

1 Foreword With the implementation of China's western development strategy and the development of the oil and natural gas industry, the proportion of natural gas in China's energy mix is ​​expected to increase gradually from 2.7% to 6.8% in the next 10 years. It is estimated that the national natural gas consumption will be reached by 2010. It will reach about 120 billion m3A1B. Under such gas source conditions, the use of natural gas as fuel for centralized heating and cooling 2-4 will change the way of central heating that uses coal as fuel for a long time, and will optimize the urban energy structure and save energy. Energy and improving the urban atmosphere are of great significance. In the following, through the engineering example, the three types of cold and heat source schemes for the central heating and cooling of natural gas fuels are compared and their selection suggestions are proposed.

2 project plan.

2.1 Project Overview Heating and cooling with natural gas as fuel. The heating building area is 600,000 m2, the cooling building area is 300,000 m2, the corresponding thermal load is 37.3 ME, and the cooling load is 23.2 ME. For this reason, there are three types of cold and heat sources for the joint operation of the basic heat source and the peaking heat source. Scheme: Scheme I: Taking the thermal power plant as the basic heat source; Scheme II: Centralized heating boiler house as the basic heat source; Scheme 3: Direct-fired lithium bromide unit as the basic heat source. In addition, each of the above solutions needs to reconstruct and use existing or new-built heating boiler rooms as peaking heat sources to meet the needs of cooling and heating loads.

2.2 Scenario 1 The scheme uses natural gas-fired thermal power plants as the basic heat source to transform several existing heating boiler rooms (or new ones) into peak heat sources. The thermal power plant has two 20t/h natural gas-fired power station boilers and one B1.5 back-pressure turbogenerator unit. Under normal operating conditions, the thermal power plant may provide steam for expansion gaps, and both ends of the electrode assembly maintain good insulation properties with the furnace shell to prevent the electrodes from being damaged due to poor sealing and causing the zinc vapor to infiltrate and cause electrode short circuit and damage to the electrodes. Deflection of the electrode holder, lack of expansion gap at the end of the electrode nut, and cracking of the electrode caused by electrode pressing. Therefore, improving the electrode sealing material and the sealing structure to ensure the electrode mounting quality is very important for reducing the electrode loss.

By suppressing the graphite electrode oxidation, the quality of the electrode installation is ensured, and the electrode unit consumption is reduced from 2.7 kg/t hard zinc to 1.85 kg/t hard zinc.

Recycling of waste oil The vacuum pump is an important equipment in the production of vacuum furnaces. In order to maintain the normal operation of the vacuum pump and to achieve the degree of vacuum required by the process, the vacuum oil of the vacuum pump must be periodically replaced. The waste vacuum oil used after the vacuum pump contains mainly moisture, zinc powder and zinc oxide dust. A large amount of waste vacuum oil adds many difficulties to storage and handling.

The filtration and regeneration method of oil substances generally includes pressure type and centrifugal filtration methods. There are also vacuum oil purification devices, which use the flash evaporation principle to remove water and use bag filters to remove impurities. The working principle of the TYA oil filter unit is to transfer the oil containing particulate impurities through a heater into the water separator using the enhanced hydrophilic and hydrophobic technology to change the interaction between the oil and water phases and accelerate the fine water droplets in the oil. It moves and coalesces into large droplets that separate out of the oil. The oil then enters the vacuum tank where flash pressure is used to remove the remaining traces of oil in the oil and then enter the high-precision filter to remove particulate impurities. The workflow is as follows: Trap! Vacuum cans! Oil pump! Secondary filter! Fine filter! Purified oil using Tya oil filter as the main component of the filter line processing waste vacuum oil, vacuum oil can be recycled every year 108. 4 Conclusion In the magnetic regulator input 200kvar capacity additional compensator, vacuum furnace power factor increased by 25% , Saving 5%. Phosphate impregnated graphite electrode to ensure the quality of electrode installation, can effectively inhibit the oxidation rate of the electrode and prevent electrical and mechanical fracture failure of the graphite electrode, reduce the consumption of graphite electrode 30%. TYA oil filter consisting of The filter line, annual renewable vacuum oil 108, fundamentally solves a series of environmental problems brought about by the disposal of waste vacuum oil, and has significant social benefits.

EVA Foam Tube

EVA Foam Tube,EVA Protective Foam Tube,Hollow EVA Foam Tube,Thin EVA Foam Tube,EVA Foam Handle,EVA Foam Column

KEYUACE Materials Co., Ltd. , https://www.insulationtubing.com