Boiler water that is removed from the boiler in order to maintain the desired concentration levels of suspended and dissolved solids in the boiler and removal of sludge.
The action to evacuate liquids or solids from a housing by use of pressure.
The periodic removal of water from a boiler to remove concentrations of sludges accumulating in the boiler.
or Cylinder Blowdown: Blowdown occurs during the period between exhaust valve opening and BDC. It is the period (measured in crank degrees) during which residual exhaust gases are expelled from the engine before the exhaust stroke begins. Residual gasses not discharged during blowdown must be physically "pumped" out of the cylinder during the exhaust stroke, lowering power output from consumed "pumping work."
Pressurizing gas flowing through a fixed orifice with no other regulation to expel liquid propellants.
Partial venting or draining, under pressure, of the water side of a boiler to reduce or remove unwanted contaminants. Also the pressure drop after releasing a pressure-relief valve.
The discharge of recirculating water for the purpose of discharging materials within the system. This eliminates the buildup of materials that could cause damages.
The difference in pressure between the opening pressure and reclose pressure of a valve. May be expressed in percentage of set pressure or "psig". ( 055)
The water continuously or intermittently purged from a system to remove sludge and keep total dissolved solids at a desired concentration. Blowdown is often expressed as a percentage of steam produced or as a percentage of the evaporation rate.
In reference to boiler & cooling tower technology, the purge from the system of a small portion of water concentrated with contaminants in order to maintain the level of dissolved and suspended solids in the system below a certain maximum level.
Water discharged from the system to control concentration of salts or other impurities in the circulating water.
The process of withdrawing water from a boiler system in order to avoid the excessive concentration of dissolved solids.
1. In a safety valve, the difference between opening and closing pressures. 2. In a steam boiler, the practice of periodically opening valves attached to the bottom of steam drums and water drums, during boiler operation, to drain off accumulations of sediment.
The withdrawal of water containing a high concentration of solids from an evaporating water system (such as a boiler system) in order to maintain the solids-to-water concentration ratio within specified limits.
The drain connection including the pipe and the valve at the lowest practical part of a boiler, or at the normal water level in the case of a surface blowdown. The amount of water blown down.
A system in a cooling tower whereby some of the circulating water is bled off and replaced with fresh water to dilute the sediment in the sump.
The process which removes oxidized contaminants or particulate waste from a vessel in order to maintain the solids-to-water concentration ratio within specified limits.
