Application of Industrial Processing Water
Chapter one Introduction
In industrial processing water is used in numerous applications requiring likewise different qualities of water. Examples of different use are cooling water, water for rinsing and chemical production, boiler feed water, purified water, water for injection, just to mention a few of those. On a chemical site or within a factory commonly a central water production unit is providing the basic amount of water in several qualities. These water supply units are using more and more surface water like river or reservoir water substituting ground or well water in the production of potable water or industrial process water. The reasons are increasing costs for ground water (taxes,...) and new available technologies enabling a quality and cost efficient (less O&M costs) treatment e.g. membrane filtration. 15 years ago reverse osmosis (RO) became state-of-the-art for the production of demineralised water (boiler feed or process water) from conventionally pretreated surface water. Recently direct ultrafiltration (UF) of those surface water without any pretreatment except a common screen filter has become a suited solution for direct production of pure water (e.g. potable water) or as an efficient pretreatment in combination with RO. A conventional surface water treatment plant consists of a multi-step process applying screen-filtration, ionization, coagulation and flocculation, sedimentation, sand filtration, and usually disinfection as a last step. The use of ozone, flocculents, hydrogen peroxide, lime and chlorine requires special precautions for safety purposes. Each step of this process has to be controlled to get an optimal performance of the overall process, which results in a complex control system. As opposed to this, the UF membrane filtration process provides the following advantages: Very high pure water quality – practically independent of variations in raw water quality. The membrane plant is easier to automate owing to its simple
In industrial processing water is used in numerous applications requiring likewise different qualities of water. Examples of different use are cooling water, water for rinsing and chemical production, boiler feed water, purified water, water for injection, just to mention a few of those. On a chemical site or within a factory commonly a central water production unit is providing the basic amount of water in several qualities. These water supply units are using more and more surface water like river or reservoir water substituting ground or well water in the production of potable water or industrial process water. The reasons are increasing costs for ground water (taxes,...) and new available technologies enabling a quality and cost efficient (less O&M costs) treatment e.g. membrane filtration. 15 years ago reverse osmosis (RO) became state-of-the-art for the production of demineralised water (boiler feed or process water) from conventionally pretreated surface water. Recently direct ultrafiltration (UF) of those surface water without any pretreatment except a common screen filter has become a suited solution for direct production of pure water (e.g. potable water) or as an efficient pretreatment in combination with RO. A conventional surface water treatment plant consists of a multi-step process applying screen-filtration, ionization, coagulation and flocculation, sedimentation, sand filtration, and usually disinfection as a last step. The use of ozone, flocculents, hydrogen peroxide, lime and chlorine requires special precautions for safety purposes. Each step of this process has to be controlled to get an optimal performance of the overall process, which results in a complex control system. As opposed to this, the UF membrane filtration process provides the following advantages: Very high pure water quality – practically independent of variations in raw water quality. The membrane plant is easier to automate owing to its simple