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Ways and methods to reduce steam waste. As we all know, steam is generated by heating water until it boils, a process that 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. Steam waste is evident in all stages, including steam generation, transmission, heat exchange utilization, and waste heat recovery. Steam energy conservation begins with every aspect of the steam system, including its design, construction, 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. A good 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%. The main ways in which energy is wasted in boilers fall into two categories. The visible aspects include the flue gas temperature of the boiler, the feedwater temperature and air preheating, the amount of sludge discharged, heat loss from the boiler itself, and the emissions from the deaerator. The invisible aspects include incomplete combustion, the air excess factor in combustion, and the recovery of latent heat of vaporization from the flue gases of gas boilers. It also includes heat recovery from boiler carryover (steam with water) and desalination boiler water. Steam carrying water is something that customers often overlook or are unaware of; a 5% carryover rate (which is quite common) results in a 1% decrease in boiler efficiency. Moreover, steam with water content increases the maintenance requirements for the entire steam system, reduces the output of heat exchange equipment, and requires higher pressures. Load mismatch is a significant cause of waste in steam energy utilization; using a large engine for a small task or a small engine for a large task both lead to low efficiency in the steam system. Watt’s experience in energy conservation is to use 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 water 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 care must be taken to protect steam pipes installed on flooded surfaces or inside pipes, to prevent them from being submerged in water. It is also necessary to protect the insulating 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 insulation 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 moist 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, to ensure that the steam supplied for heat exchange 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 step-by-step utilization, making use of steam energy layer by layer. 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, in order to lower the temperature of the condensate and reduce the likelihood of flash vapor formation. If drainage at saturation must be carried out promptly, the recovery and reuse of flash steam need to be considered. Leakage from the steam trap in heat exchangers is one of the main causes of steam waste; selecting the appropriate steam trap and carrying out timely inspection and maintenance can help reduce such waste. Steam traps must ensure free drainage from the heat exchanger under any conditions, to avoid steam waste caused by activating 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 blowdown, thereby cutting costs. Recycling condensate water also decreases the amount of make-up water needed for the deaerator, thus saving on water and water treatment expenses. 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. The design of steam systems must 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 sound metering 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.