Boiler blowdown rate
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May I ask whether the sewage discharge rate mentioned here refers to both continuous and scheduled discharge, or only continuous discharge? Is there any specific clarification on this in the standard?
The blowdown rate refers to the ratio of the continuous blowdown flow rate of the boiler to the actual evaporation volume. The Code for Design of Boiler Rooms stipulates that for steam boilers with a steam pressure of 2.5 MPa or less, the blowdown rate shall not exceed 10%; for steam boilers with a steam pressure greater than 2.5 MPa, the blowdown rate shall not exceed 5%. In general, the blowdown volume for boilers should be less than 5% of the total water volume, and at most 10%.
The blowdown rate generally refers to the continuous blowdown from the boiler drum； It is generally determined based on furnace water tests; if the water quality is poor, more water is discharged. Design calculations typically use a value of 1–2%.
The pollution discharge rate refers to a value of no more than 3% for continuous discharge; the quality of the boiler water is controlled through fixed-discharge systems and chemical dosing.
Article 9.2.8 of GB50041-2008, the \"Code for Design of Boiler Rooms\", specifies requirements regarding the sludge discharge rate, but it does not provide an explanation of what this term means. As a result, I don’t understand it. Everyone says that the sludge discharge rate refers to continuous discharge, but we are facing a problem: according to the requirements of the boiler manufacturer, the sludge discharge rate for continuous discharge should be 3%, yet our rate for scheduled discharge is 17%. If, as per technical specifications, the sludge discharge rate indeed refers to continuous discharge, then they meet the requirements; however, we suffer heavy losses due to scheduled discharge, and it seems like we were deceived at the beginning. An explanation was given regarding the need to find the boiler’s blowdown rate.
Article 9.2.8 of GB50041-2008, the \"Code for Design of Boiler Rooms\", specifies requirements regarding the sludge discharge rate, but it does not provide an explanation of what this term means. As a result, I don’t understand it. Everyone says that the sludge discharge rate refers to continuous discharge, but we are facing a problem: according to the requirements of the boiler manufacturer, the sludge discharge rate for continuous discharge should be 3%, yet our rate for scheduled discharge is 17%. If, as per technical specifications, the sludge discharge rate indeed refers to continuous discharge, then they meet the requirements; however, we suffer heavy losses due to scheduled discharge, and it seems like we were deceived at the beginning. An explanation was given regarding the need to find the boiler’s blowdown rate.
Article 9.2.8 of GB50041-2008, the \"Code for Design of Boiler Rooms\", specifies requirements regarding the sludge discharge rate, but it does not provide an explanation of what this term means. As a result, I don’t understand it. Everyone says that the sludge discharge rate refers to continuous discharge, but we are facing a problem: according to the requirements of the boiler manufacturer, the sludge discharge rate for continuous discharge should be 3%, yet our rate for scheduled discharge is 17%. If, as per technical specifications, the sludge discharge rate indeed refers to continuous discharge, then they meet the requirements; however, we suffer heavy losses due to scheduled discharge, and it seems like we were deceived at the beginning. An explanation was given regarding the need to find the boiler’s blowdown rate.
Whether it is in a fixed arrangement or a sequential arrangement, it is determined by water treatment and water quality; the impact on boiler equipment is that excessive scale can lead to blockages and tube explosions.