The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous fro...The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous from municipal wastewater. This is already an established demand in many countries. However, as P is a limited raw material, this need for a reuse of P will become an example of what now is labelled “cyclic economy”. For instance, a national demand from the German state is already put in force. In this perspective the advanced filtration techniques will play an interesting role, and most possibly a crucial role. Examples are presented from several municipal WWTPs already in operation with a final polishing treatment step based on chemical precipitation and separation of phosphorus. Typical stable discharge P levels are found at these plants at levels < 0.05 to 0.10 ppm. The new demands on phosphorus recovery will also call for modified process concepts for the WWTP;for instance, a refined biological phosphorus removal (EBP) attains more attention and he needed very low discharge levels of P, where the enhanced P-removal will include different smart filtration techniques.展开更多
This paper introduces to fluid state physics （fluid mechanics） a new interpretation of physical phenomena taking place in a fluid in motion. It introduces the base of a new theory claiming that every flow has its ow...This paper introduces to fluid state physics （fluid mechanics） a new interpretation of physical phenomena taking place in a fluid in motion. It introduces the base of a new theory claiming that every flow has its own internal structure of motion, which is definite organization of motion, rather than a ＂molecular chaos＂, known from the fluid statics. The paper introduces the new notion of structures vector fields of power and momentum and shows every Newtonian fluid flows are dual in character. It shows that the flow of Newtonian fluid has a dual character. It demonstrates on models and further in mathematical interpretation of physical phenomena. It introduces, on the one hand, the cycloidal motion model into the fluid mechanics, ad on the other hand an addition to the known, the classical model of Poiseuille laminar motion. The theory of dualism （double nature of physical phenomena） allows the description of selected characteristics of the flow, either by using the theory ofcycloidal motion （semicycloidal）, or by using the supplemented theory of laminar motion. The dualism theory is useful to describe each type of flows both, laminar and turbulent. This paper is only an introduction to the theory. It has been assigned number 1. It has been granted a high priority, since it contains basic concepts that will be used in others, following papers of long cycle.展开更多
In fluid mechanics, there is lack of turbulent flows theory. The theory of laminar flows is also not completed. Therefore, the aim of this paper is to fill in the gaps in the theory of laminar flow. First time in the ...In fluid mechanics, there is lack of turbulent flows theory. The theory of laminar flows is also not completed. Therefore, the aim of this paper is to fill in the gaps in the theory of laminar flow. First time in the history of fluid mechanics, it shows that the value of the boundary Reynolds number, dividing the flows of Newtonian fluids into laminar and turbulent, can be calculated theoretically. The very existence of this boundary has been known to researchers over a century ago, but all knowledge in this area so far comes only from experimental physics. This paper marks a turning point, as it not only explains the theory of the said phenomenon, but also presents the methodology of its analytical description. It should be noted that the said description refers to the type of flow which is best understood by scientists, i.e., steady axially-symmetric laminar flow through a straight-axis duct of a circular cross-section of the radius R under the action of constant natural gravitational forces. This paper comes second in a series of papers aimed at eliminating chaos from fluid mechanics and replacing it with harmony and mathematical order.展开更多
文摘The need for an advanced and even far reaching phosphorus removal at municipal WWTPs may soon get stipulations in relation to a reuse of phosphorus (P). This paper discusses the possible ways to remove phosphorous from municipal wastewater. This is already an established demand in many countries. However, as P is a limited raw material, this need for a reuse of P will become an example of what now is labelled “cyclic economy”. For instance, a national demand from the German state is already put in force. In this perspective the advanced filtration techniques will play an interesting role, and most possibly a crucial role. Examples are presented from several municipal WWTPs already in operation with a final polishing treatment step based on chemical precipitation and separation of phosphorus. Typical stable discharge P levels are found at these plants at levels < 0.05 to 0.10 ppm. The new demands on phosphorus recovery will also call for modified process concepts for the WWTP;for instance, a refined biological phosphorus removal (EBP) attains more attention and he needed very low discharge levels of P, where the enhanced P-removal will include different smart filtration techniques.
文摘This paper introduces to fluid state physics （fluid mechanics） a new interpretation of physical phenomena taking place in a fluid in motion. It introduces the base of a new theory claiming that every flow has its own internal structure of motion, which is definite organization of motion, rather than a ＂molecular chaos＂, known from the fluid statics. The paper introduces the new notion of structures vector fields of power and momentum and shows every Newtonian fluid flows are dual in character. It shows that the flow of Newtonian fluid has a dual character. It demonstrates on models and further in mathematical interpretation of physical phenomena. It introduces, on the one hand, the cycloidal motion model into the fluid mechanics, ad on the other hand an addition to the known, the classical model of Poiseuille laminar motion. The theory of dualism （double nature of physical phenomena） allows the description of selected characteristics of the flow, either by using the theory ofcycloidal motion （semicycloidal）, or by using the supplemented theory of laminar motion. The dualism theory is useful to describe each type of flows both, laminar and turbulent. This paper is only an introduction to the theory. It has been assigned number 1. It has been granted a high priority, since it contains basic concepts that will be used in others, following papers of long cycle.
文摘In fluid mechanics, there is lack of turbulent flows theory. The theory of laminar flows is also not completed. Therefore, the aim of this paper is to fill in the gaps in the theory of laminar flow. First time in the history of fluid mechanics, it shows that the value of the boundary Reynolds number, dividing the flows of Newtonian fluids into laminar and turbulent, can be calculated theoretically. The very existence of this boundary has been known to researchers over a century ago, but all knowledge in this area so far comes only from experimental physics. This paper marks a turning point, as it not only explains the theory of the said phenomenon, but also presents the methodology of its analytical description. It should be noted that the said description refers to the type of flow which is best understood by scientists, i.e., steady axially-symmetric laminar flow through a straight-axis duct of a circular cross-section of the radius R under the action of constant natural gravitational forces. This paper comes second in a series of papers aimed at eliminating chaos from fluid mechanics and replacing it with harmony and mathematical order.
