Diffuser (sewage)

About: Diffuser (sewage) is a research topic. Over the lifetime, 6487 publications have been published within this topic receiving 40404 citations.

Liquid aerating apparatus

Abstract: An apparatus for aerating liquid including an upwardly extending throat having an impeller for pumping liquid upwardly through the throat and a diffuser overlying the upper end of the throat to direct the liquid outwardly in an annular spray pattern, a motor mounted above the diffuser for driving the impeller, and an electrical heater extending around the outer periphery of the diffuser for inhibiting formation of ice on the aerator. The heater is in the form of a ring that overlies the upper side of the diffuser outwardly of the motor and preferably extends outwardly of the periphery of the diffuser at a level to limit the height of the liquid spray pattern.

Diffuser for centrifugal compressors

Abstract: This invention relates to diffusers for centrifugal compressors designed for the improvement of the efficiency thereof. The diffusers forming the subject of this invention are also adapted to be associated, if necessary, with a transfer arrangement for directing compressed elastic fluid from...

Effect of Degassing Treatment on the Quality of Al-7Si and A356 Melts.

Abstract: A degassing treatment is necessary to assure the quality of aluminum alloy castings. Its effect on the mechanical properties of the A356 alloys has been well studied and documented. This study assessed the effect of different degassing diffusers, a lance and a porous bar, on the areas of the foggy marks and the pore counts as revealed in the chilled Al-7Si and the A356 alloy sample sections. The degassing bubbles rose in the melt floating with induced convection loops during degassing. The porous diffuser generated a strong and wide convection loop in the melt. There are two bubble explosion sites when a porous diffuser was used: one in the area close to the wall of the crucible and another near the diffuser. Using a lance diffuser generated a coarse-bubble cloud near the diffuser during degassing. For Al-7Si alloy, different diffusers produced a close ratio of foggy marked area and a close pore count but the quality of A356 alloy melt was affected by diffusers and/or Sr addition. During rotating bending tests, the fatigue life of the specimens was affected by the pore count and the relative porosity, but was irrelevant to the foggy marks.

Bubble generation by micro-orifices with application on activated sludge wastewater treatment

Abstract: We studied the initial gas dispersion performance of diffuser concepts based on micro-orifices and needles with very fine orifice diameters in the range from 37 μm to 225 μm, as such diffusers are currently in discussion for energy-efficient wastewater treatment plants. To evaluate the performance of these micro-orifices, we compared them with industrial rubber membrane diffusers with respect to Sauter mean bubble diameter, pressure drop, frequency of bubble formation, oxygen transfer rate, and power demand for air compression. Our study revealed that, in comparison with current state of the art of rubber membrane diffusers, bubbles generated from the micro-orifices transfer up to 22% more oxygen content into the continuous phase at up to 51% less power demand. Moreover, these micro-orifices are able to produce bubble sizes in the same range as the needle diffusers at 60% less pressure drop and 60% higher bubble generation frequency.

Method and apparatus for reducing speckle in coherent light

Abstract: According to one embodiment, a method for reducing speckle in an image produced from a coherent light source includes directing a beam of coherent light at an electrically controlled diffuser. An electrical signal is applied to the electrically controlled diffuser to produce an electrical field across the electrically controlled diffuser layer. At least one of an amplitude and a frequency of the electrical signal are varied to transition the controlled diffuser between a first state and a second state. The varied application of the electrical signal operates to reduce spatial coherence in an image projected through the electrically controlled diffuser.