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Optimization of steam systems: Water vapor is the most commonly used heating medium in industrial processes. It is generated by heating water until it boils, which requires a large amount of petrochemical energy. Any waste of steam leads to energy loss and environmental pollution, imposing additional economic burdens and social responsibilities on steam users. How to reduce steam waste is reflected in various stages such as steam generation, transportation, heat exchange utilization, and waste heat recovery. The steam system is a complex self-balancing system that encompasses every process, including its design, installation, maintenance, upkeep, and optimization. Watt Energy Saving’s experience over the past 40 years shows that most customers have significant potential and opportunities for energy savings. Practice has shown that a proper steam system can help steam users reduce energy waste by 5–50%, which holds significant economic and social value. In the process of steam generation, it is first necessary to choose a steam boiler that is well-designed and manufactured. The design efficiency of boilers should ideally be over 95%. There are many factors that contribute to energy waste in boilers; the visible ones include the boiler’s flue gas temperature, the boiler feedwater temperature, and air preheating in the burners, as well as slag discharge control, heat loss from the boiler itself, and the emissions from the deaerator. The invisible aspects include incomplete combustion, the air excess factor for combustion, and the recovery of latent heat of vaporization from the flue gases of gas boilers. It also includes boiler carryover (wet steam). Steam carryover is a aspect that is often overlooked or unknown by users; 5% carryover (which is quite common) results in a 1% decrease in boiler efficiency. Moreover, steam containing water leads to increased maintenance requirements for the entire steam system, reduces the output of heat exchange equipment, and necessitates higher pressures. First and foremost, it is necessary to carefully select steam boilers, steam pipelines, heat exchangers, drain valves, etc., based on the load; any overly large selection may result in energy waste and increased initial investment. Load mismatch is a major cause of waste in steam energy utilization; using a large engine to drive a small device, or vice versa, leads to inefficiency in the steam system. Watt’s experience in energy savings involves using Watt steam thermal storage balancers in applications with frequent peak and off-peak loads. During transportation, steam must heat the entire steam network to its boiling temperature, which inevitably leads to condensation of steam. Watt Energy Saving refers to this amount of condensed water generated during the heating of the steam network at startup as the system’s startup load. When steam is being transported, due to the temperature difference between the external environment and the steam inside the pipes, the steam continuously loses heat to the environment. This heat loss causes some of the steam to condense, resulting in the formation of condensate water. We define the level of moisture content in the condensed water within the steam as the dryness degree of the steam. Watt Energy Saving refers to this portion of condensate water as the pipeline system operation load. Good insulation is an important factor in reducing steam waste, and the effectiveness of most insulating materials depends on the tiny air pockets contained within inert materials such as mineral wool, fibreglass, or calcium silicate. Typically, aluminum-clad fiberglass, aluminum-clad mineral wool, and calcium silicate are used for installation. It is important that the insulation material does not deform or get wet. Appropriate mechanical protection and waterproofing are necessary, especially for outdoor installations. The heat loss from steam pipes due to exposure to water or humid insulation materials can be as much as 50 times greater than the heat lost to the air. Therefore, special attention must be paid to protecting steam pipes installed on flooded surfaces or inside pipes, to prevent them from being submerged in water. It is also necessary to protect the insulation layer from being damaged by objects such as ladders, in order to prevent rainwater from penetrating. Apart from the safety valve, all hot parts of the steam system need to be insulated. This includes all the main connection flanges, valves, and other fittings. At the same time, the insulating layer on each side of the connection flange must be cut away to expose the bolts and provide space for maintenance. This is equivalent to a light tube length of 0.5 m. Even good insulation cannot completely prevent heat loss and condensation during steam transmission. When steam containing some condensed water becomes humid and corrosive, the increasing amount of condensed water provides sufficient \"head pressure\" for the rapidly flowing steam, resulting in high-kinetic-energy \"water projectiles\" or water hammers. Water hammer can cause a range of damages to steam systems; pipes, valves, elbows, flanges, instruments, and heat exchange equipment may all be deformed or damaged by the force exerted by water hammer, which can lead to safety accidents in severe cases. Therefore, the proper pipeline must be equipped with several steam traps along its length to enable the immediate and automatic removal of steam condensate. Inappropriate steam traps are a major cause of steam waste. In the steam distribution system, for intermittent steam users, when steam use is stopped for an extended period, the supply must be cut off at the source of steam (such as the distribution cylinder in the boiler room). For pipelines that use steam seasonally, a separate steam pipeline must be employed, with a Watt high-temperature ball valve used to cut off the supply during periods when steam is not in use. The steam entering the steam utilization point must contain as little condensate, non-condensable gases, and dirt as possible; the use of online filters and debris removal measures ensures that the steam entering the heat exchanger is clean, dry saturated steam. A decrease in steam quality leads to increased flow requirements, resulting in hidden steam waste. Soda water heat exchangers must be equipped with temperature control; the temperature control valve can be installed in the steam system or used to control the condensate system. Any temperature above the required level means excessive heating and waste of energy. The use of any pressure relief valve in the steam system implies a decrease in the quality of the steam; an appropriate steam pressure is an important factor in reducing steam waste. Using it under reduced pressure is an invisible form of energy waste. The best way to use steam is through staged utilization, making use of steam energy layer by layer. Using a static mixer in place of a steam pressure reducer allows for the effective utilization of the potential energy of high-quality steam to boost low-quality steam (waste steam, flash steam), thereby enabling the staged and progressive use of steam. The steam traps of the heat exchanger must ensure unobstructed drainage of steam. The selection of the heat exchanger should take into account the use of the sensible heat of steam, thereby reducing the temperature of the condensate and minimizing the possibility of flash vapor formation. If saturation drainage is necessary, the recovery and reuse of flash vapor must be considered. Leakage from heat exchanger steam traps is one of the main causes of steam waste; selecting appropriate steam traps and conducting timely inspections and maintenance can help reduce steam waste. Steam traps must ensure free drainage from the heat exchanger under any conditions, to prevent steam waste caused by the activation of the trap bypass. The condensed water after heat exchange must be recovered promptly. Benefits of condensate recovery: Recovering the sensible heat from high-temperature condensate helps save fuel; for every 6°C increase in water temperature, boiler fuel consumption can be reduced by about 1%. Increasing the boiler efficiency helps to maintain the steam-generation capacity of the boiler at its maximum level. Condensate water is free of salts, and using it reduces the frequency of boiler blowdowns, thereby cutting costs. Recycling condensate water also decreases the amount of water needed as make-up water for the deaerator, thus saving on water and water treatment expenses. Good temperature control is an essential aspect of steam heat exchange. It not only protects the products being heated, but also allows for timely adjustment of the steam supply in response to changes in load, thereby achieving the minimum steam consumption required for the manufacturing process. Use as few manual valves as possible to prevent steam leaks and pressure losses; install sufficient display and indicator instruments to enable timely assessment of the steam’s condition and parameters. Installing sufficient steam flow meters can effectively monitor changes in the steam load and detect potential leaks in the steam system. Recovering condensate water increases the operational stability of the boiler, thereby improving the quality of steam and reducing energy consumption. By raising the temperature of the feedwater, the oxygen content is minimized, which in turn helps to reduce system corrosion. It reduces the emission of fuel gases and the release of hot water into the environment, thereby protecting the environment. Watt believed that the design of steam systems should minimize environmental impact by reducing the use of various unnecessary valves and piping fittings. The steam system requires proper daily management and maintenance; establishing appropriate technical standards and management procedures, along with leadership attention, as well as the assessment of energy-saving targets and effective measurement and data management, are essential for reducing steam waste. Hangzhou Watt Energy Saving believes that the training and assessment of operators and managers are key to saving steam energy and reducing steam waste.