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This post was last edited by yinkuilin6868 on 2015-11-17 at 14:43. Summary: General machinery products such as pumps, fans, compressors, and drying equipment are energy-consuming products that are used on a large scale. The State Council’s notice regarding the issuance of the 12th Five-Year Plan for energy conservation and emission reduction, Document No. Guo Fa (2012) 40, specifies that “the energy efficiency standards for newly added major energy-consuming devices such as fans, compressors, and pumps should reach domestic or international advanced levels…” Therefore, it is of great practical and long-term significance for China to develop high-efficiency, energy-saving general machinery products and to continuously improve the energy-saving technologies associated with these products. This approach is crucial for reducing energy consumption, improving energy utilization rates, and helping various sectors of the national economy achieve their goals in terms of energy conservation and emission reduction. I. Development and Application of Energy-Saving Products for General Machinery. There are a wide variety of general machinery products, among which pumps, fans, and compressors are the most numerous and widely used. Based on the annual production volume and the number of units put into operation for these types of products, it is estimated that their annual electricity consumption accounts for about 40% of the total industrial electricity consumption in the country. Of this amount, 20% is used for pumps, 10.4% for fans, and 9.6% for compressors. Energy is a **foundation for economic development**, and as China’s energy demand continues to rise, it faces significant pressure to reduce emissions and conserve energy. Especially as energy-saving efforts advance, it becomes more difficult to further tap into potential for energy savings, making the task of saving energy even more challenging. There is an urgent need for the whole society to reach a consensus on product energy efficiency, innovations in system energy conservation, as well as their promotion and application, so as to achieve greater breakthroughs in energy-saving technologies in our country. To accelerate the industrialization of energy-saving technologies and equipment, China has successively issued the \"Decision on Accelerating the Cultivation and Development of Strategic Emerging Industries,\" the \"12th Five-Year Plan for the Development of Strategic Emerging Industries,\" the \"12th Five-Year Plan for the Development of Energy-Saving and Environmental Protection Industries,\" and the \"Opinions on Accelerating the Development of the Energy-Saving and Environmental Protection Industry.\" These documents emphasize the importance of promoting the industrialization of key energy-saving technologies and equipment as a core aspect of developing these industries. Various policy measures have been strengthened, creating a favorable policy environment for advancing innovation and industrialization in energy-saving technologies. As a result, the general machinery manufacturing industry faces significant opportunities for development. Improving the energy-saving technology level of general machinery products is an important measure to promote industrial transformation and upgrading. In recent years, the general machinery industry has been continuously strengthening innovation in energy-saving technologies for products and systems, and actively promoting the development, adoption, and dissemination of such energy-saving technologies. At present, the proportion of energy-saving products in the categories of pumps, fans, and compressors has increased significantly, rising from 10% to 30%. Revisions to the energy efficiency standards for pumps, fans, and compressors have been initiated, draft standards for system energy conservation have also been prepared, and the energy efficiency standards for drying equipment have been submitted for approval. Waste energy recovery technology has received attention in companies that manufacture pumps, fans, and compressors. Some of these companies have developed waste energy recovery systems and equipment, and have implemented them on a wider scale, achieving significant energy-saving results. More and more enterprises are adopting contract energy management to set energy-saving targets and performance goals with their customers. Some manufacturing companies have evolved from merely providing energy-saving products to offering system-based energy-saving solutions to their customers. Overall, however, there is still a certain gap between the level of energy-saving technology in China’s general machinery products and the demands for further energy savings, which is mainly reflected in the weak capacity for independent innovation. The energy-saving technology innovation system centered on enterprises is imperfect; the integration of industry, academia, and research is not strong enough; investment in technology development is insufficient, and energy-saving technologies for some core systems have not yet been fully mastered ； Second, the industry concentration is low. Enterprise sizes are generally small, and leading enterprises fail to play a strong role in driving development; the level of integration, standardization, and serialization of energy-saving products is low ； Third, the policies are imperfect. Relevant regulations, standard systems, as well as fiscal and financial policies are inadequate, making it difficult for small and medium-sized manufacturing enterprises to obtain financing ； Fourth, the market-based promotion system is incomplete. There are few channels for the dissemination of information on energy-saving technology products between users and suppliers; the third-party evaluation mechanisms are inadequate. Users have a low level of awareness regarding new energy-saving technologies and equipment, and the cost of identifying such technologies is high. Market-based promotion models such as contract energy management and equipment leasing have not been widely adopted. Some products that were originally designed to be energy-efficient become less energy-efficient when used in engineering applications. The reasons for this situation are as follows: First, the system design is not reasonable. When calculating the resistance of pipelines, the design agencies increase the resistance coefficient as a safety measure. For example, if the head required to transport the fluid is 100 meters, the design agency adds a 10% safety factor, resulting in a head of 110 meters. In turn, pump, fan, and compressor manufacturers also include a safety factor of 120 meters when designing these devices. On top of this, the standards require a safety factor of 1.1 for the motors used. The combination of all these safety factors leads to a situation where overpowered equipment is used, turning what were originally energy-efficient products into ones that are not energy-efficient ； Secondly, the high efficiency of energy-saving products such as pumps, fans, and compressors refers to their operating efficiency under rated conditions (full load), as this is when they are the most energy-efficient. However, when the equipment is in operation, it often deviates from the optimal operating range, and at such times energy-saving products cease to be energy-saving. Just as for cars with a displacement of 2.0 liters or less, the most fuel-efficient driving speed is between 70 and 100 kilometers per hour; driving at speeds other than these results in higher fuel consumption. According to statistics, over 70% of pumps, fans, compressors and other such products in our country operate under conditions that deviate from their optimal operating parameters; in such cases, their average efficiency is less than 70%. Products that originally had an efficiency of 90% see their efficiency drop by 20%, which represents a great waste of energy. II. Development and Application of Waste Energy Recovery Technologies The definition of waste energy recovery is quite broad; in essence, it involves converting the remaining portion of energy that has already been used into energy that can be reused, such as transforming heat energy, mechanical energy, pressure energy, light energy, etc., into usable forms of energy. Exergy recovery enables the full utilization of energy, reduces carbon emissions, and helps save energy and resources, which is beneficial for sustainable development. Currently, the general machinery industry is conducting research on waste energy recovery technologies and developing new products for waste energy recovery. For example, steam turbines for recovering waste heat from steam, hydraulic turbines (water turbines) for recovering energy from residual pressure in liquids, and screw expansion devices for recovering low-grade waste heat. (1) The energy possessed by the liquid fluid (water) in the hydraulic turbine flow is converted into kinetic energy as it passes through the turbine nozzle. As the fluid flows over the impeller, it impacts the blades, causing the impeller to rotate and thereby driving the turbine shaft to spin. The turbine shaft drives other machinery directly or through a transmission mechanism to deliver mechanical work. The liquid (water) passes through the rotating wheel, entering a hydraulic turbine operating mode. Under certain conditions, hydraulic turbines can replace drive devices such as electric motors or steam turbines, and they can recover up to 80% of the fluid’s energy, which can then be used to power pumps, fans, compressors, or other rotating machinery. For example, the hydraulic turbines developed by Shandong Changzhi Pump Industry Co., Ltd. are capable of recovering an average power of 300 kW per unit. Assuming they operate for 300 days per year, each such turbine can save 2.16 million kWh of electricity per year, resulting in cost savings of 1.51 million yuan – indicating very significant economic benefits. In addition, companies such as Dalian Deep Blue Pump Industry have also developed efficient hydraulic turbine units, which have achieved good energy-saving results when applied in various fields. (II) Screw expander: A screw expander belongs to the category of positive-displacement expanders. It is a power machine that generates work by drawing in gaseous working fluid at a certain pressure, causing the elementary volume to expand continuously from small to large; it represents the reverse operation of a screw compressor. The principle by which screw expanders are used for waste heat recovery is achieved through an organic Rankine cycle. The organic Rankine cycle is the reverse cycle of a common refrigeration cycle, and it enables the conversion of low-grade thermal energy into electrical energy or mechanical energy. Currently, the rotor profiles of screw expanders developed in China ensure high efficiency, low noise, and high reliability for these expanders, enabling them to meet the expansion requirements of water vapor with different mass flows. The organic Rankine cycle screw expansion generator sets developed and produced by Zhejiang Kaishan Compressor Co., Ltd. use a screw expander connected directly to the generator to produce electricity, without the need for speed increase or reduction gears. This not only eliminates the power loss associated with gears as well as transmission noise, but also improves the reliability of the system. The first screw expansion generator set based on the organic Rankine cycle developed by this company was successfully applied at Tianjin Tianfeng Steel Company, where it generated electricity on the grid without any issues, earning recognition from the market. To date, dozens of orders have been placed for such units. (III) Turbine expansion units: In recent years, Shaanxi Blower Group Company has carried out numerous studies and product developments in the area of recovering excess energy from turbine expansion, focusing on the development of three types of products. 1. Pure-low-temperature waste heat recovery system: The pure-low-temperature waste heat recovery system developed by Shaanxi Blower Group relies on its core technology of utilizing the low-grade thermal energy contained in waste gas and flue gases with temperatures below 380°C, which are discharged into the atmosphere, to generate electricity or directly power mechanical equipment. This system consists of heat exchangers designed for low operating parameters, low-parameter steam turbines, and generators; it also includes mechanisms for recovering dust from the exhaust gases. It is currently mainly used in the cement, steel, and petrochemical industries. Each set of cryogenic waste heat recovery system can generate 72 million kWh of electricity per year ； Annual recycling benefits exceed 30 million yuan ； 25,500 tons of standard coal can be saved each year ； It can reduce carbon dioxide emissions by 69,000 tons per year. 2. Devices for recovering and utilizing waste energy in industrial processes: Such devices are widely used for the recovery and comprehensive utilization of waste energy in production processes such as metallurgy, *ao acid, and purified terephthalic acid. Among them, the blast furnace gas excess pressure power generation turbine unit is a device that converts the pressure energy and thermal energy contained in the blast furnace top gas, a by-product of iron smelting, into mechanical energy to drive a generator to produce electricity. China’s metallurgy industry is the largest energy consumer in the country, accounting for 13%–15% of the nation’s total electricity consumption. Installing a Blast Furnace Gas Excess Pressure Power Generation Turbine (TRT) is an important way for metallurgical enterprises to save energy and reduce consumption. It can help steel companies reduce their reliance on purchased electricity by 6%–8%. 3. Gas-steam combined cycle power generation unit: This type of power generation unit first mixes blast furnace gas with desulfurized coke oven gas; the mixture is then pressurized by a gas compressor and burned in combination with air sent to the combustion chamber, resulting in high-temperature, high-pressure gases. These gases expand through a gas turbine to generate power, which in turn drives the compressor as well as external loads to rotate at high speeds. The exhaust gases from the gas turbine are directed to a waste heat boiler, where they produce high-temperature, high-pressure steam that drives a steam turbine; together with the gas turbine, this steam turbine drives the generator to produce electricity. Generally speaking, the thermal efficiency of using blast furnace gas as fuel in boilers to generate steam for driving turbines to produce electricity is only around 25%, whereas the thermal efficiency of gas-steam combined cycle power plants can reach 40%-50% without providing heat. The major steel plants in developed countries around the world are equipped with gas-steam combined cycle generators that use blast furnace gas as fuel. A gas-steam combined cycle power generation unit is primarily composed of key systems such as gas turbine units, gas compression units, steam turbines, generators, and waste heat boilers; these systems together form a complex and complete power generation system. Currently, the main manufacturers abroad that possess the core technologies of this system include Mitsubishi in Japan, GE in the United States, Alstom in France, Siemens in Germany, as well as Kawasaki and Mitsui in Japan, and ALSTOM in France. Shanxi Blower has invested a great deal of effort in the research and development of this turbine unit, achieving several significant technological breakthroughs; it has even received the **Second Prize for Scientific and Technological Progress. III. Development objectives for energy-saving technologies in general machinery products 1. By leveraging the existing infrastructure of **engineering centers**, **key laboratories**, and **product testing centers** in the general machinery industry, efforts should be made to strengthen the construction of a system for technological innovation, thereby establishing a number of high-level, fundamental, strategic, and cutting-edge research institutions that can support the development of energy-saving technologies, products, and related systems. Increase investment in research and development for the key and common technologies related to energy-saving products in general machinery, carry out research on system-level energy-saving technologies, overcome the core technical barriers in this field, and develop independent intellectual property rights, thereby providing technical support for the widespread adoption of energy-saving products and systems. 2. Continuously improve the energy efficiency standards, inspection standards, and evaluation rules for energy-saving products and equipment operating systems, so as to make the energy-saving indicators for general machinery products and systems in China more comprehensive and scientific. 3. Develop a range of energy-saving products in fields such as pumps, fans, compressors, and drying equipment that possess independent intellectual property rights and core competitive advantages, as well as a group of key enterprises with international competitiveness. By 2020, the market share of high-efficiency energy-saving technologies and products is to rise from the current 30% to over 60%, with production value exceeding 300 billion yuan; meanwhile, the annual energy-saving capacity will amount to 6 million tons of standard coal. 4. In the field of waste energy recovery, efforts are focused on advancing key technologies and their applications, such as the direct conversion of waste heat and pressure into mechanical energy for reuse, and the use of organic Rankine cycles to generate power from low-grade waste energy. The efficiency of recovering energy from hydraulic turbines, turbine expanders, and screw expanders is continuously improved, thereby enhancing the operational efficiency of waste energy recovery systems. **Formulate relevant policies to support the grid connection of excess energy generation as soon as possible, in order to promote the hierarchical utilization of energy based on its quality. 5. Gradually establish a number of pump, fan, and compressor manufacturing enterprises to form \"energy-saving innovation technology strategic alliances\" with manufacturers of motors, internal combustion engines, and other related products, as well as with end-users, in order to improve energy efficiency across all aspects. 6. Increase efforts to promote pump, fan, and compressor products that meet **Level 1 and Level 2 energy efficiency standards, in order to provide users with the best system energy-saving solutions. Accelerate the energy-saving upgrades of existing unreasonable pump, fan, and compressor systems. Therefore, we have reason to believe that during the 13th Five-Year Plan period, various measures will surely push China’s technologies related to energy conservation in general machinery products, system-level energy savings, and waste energy recovery to a new level, thereby achieving the goal set out in Document No. 40 issued in 2012, which is to bring the energy efficiency standards of new major energy-consuming devices such as fans, compressors, and pumps up to international advanced levels.