Seals feed tube

A thin zirconia membrane is sealed to a stainless cup of about one inch diameter (Figure 5.9). The stainless cup has a feed tube welded to it. The inside cavity is evacuated to about 5 psi and sealed off. One can calculate the leak rate by monitoring the pressure decay as a function of time (see Section 5.2.1). 

Note A typical ICP analysis requires making a solution of 9.6 ml ultra-pure water, 0.2 ml nitric acid (approximately 70% m/m HNO3), 0.1 ml marked feed sample solution (or 1 ml faecal sample solution) and 0.1 ml rhodium internal standard solution (10 pg mb in 5% v/v nitric acid solution). This is contained in a sample tube sealed with clingfilm. The sample probe is inserted through the clingfilm. A pick-up time of 35 s, and a scan time of 35 s proved satisfactory. The probe is rinsed in the 5% v/v nitric acid solution between samples. 

Figure 4.11 is a schematic of a typical hollow fine fiber element. A continuous fiber is looped into a bundle around a central feed tube. The central feed tube is sealed at the product water end and is perforated within the active membrane area. Both ends of the fiber bundle are potted in an adhesive. When cured, the adhesive and protruding fibers in the product water end are machined... 

Entering the conveyor with the feed stream is a flow of leakage air, which passes through the clearance between the conveyor and the feed tube. This air flow must eventually be vented, and in those applications where odour or toxicity is an issue, minimising this air in-flow is important. A simple, lightly contacting lip seal is often used. On critical sealing processes, mechanical seals are required. 

The main variant of the feed tube is one with a floe feature. In this design two tubes are held together concentrically. The inner tube takes the feed while the outer shorter tube is used for the flocculant or rinse. The flocculant or rinse leaves the outer tube via holes drilled radially at the sealed front end. 

Spiral-wound cartridges are inserted ia series into cylindrical pressure vessels. Feed flows parallel to the membrane surfaces ia the channel defined by the mesh spacer which acts as a turbulence promoter. Permeate flows into the center permeate-withdrawal tube which is sealed through the housing end caps. 

Influent water enters one end of the pressure vessel and travels longitudinally down the length of the vessel in the feed transport layer. Direct entry into the permeate transport layer is precluded by sealing this layer at each end of the roll. As the water travels in a longitudinal direction, some of it passes in radially through the membrane into the permeate transport layer. Once in the transport layer, the purified water flows spirally into the center collection tube and exits the vessel at each end. The concentrated feed continues along the feed transport material and exits the vessel on the opposite end from which it entered. 

Spiral-wound modules consist of several flat membranes separated by turbulence-promoting mesh separators and formed into a Swiss roll (Figure 16.18). The edges of the membranes are sealed to each other and to a central perforated tube. This produces a cylindrical module which can be installed within a pressure tube. The process feed enters at one end of the pressure tube and encounters a number of narrow, parallel feed channels formed between adjacent sheets of membrane. Permeate spirals roward the perforated central tube for collection. A standard size spiral-wound module has a diameter of about 0.1m, a length of about 0.9 m and contains about 5 m2 of membrane area. Up to six such modules may be installed in series in a single pressure tube. These modules make better use of space than tubular or flat sheet types, but they are rather prone to fouling and difficult to clean. 

Equipment, The reactor was 1.523 liter, 316 stainless steel cylindrical, jacketed vessel equipped with two multiblade, paddle-type agitators. Tracer studies showed the reactor was well-mixed. A thermocouple measured temperature and was recorded continuously. Feed tanks, tubing, pumps and valves were made of stainless steel and had teflon seals. 

A flattened membrane tube, or two sheet membranes sealed at both edges (and with a porous backing material inside if necessary), is wound as a spiral with appropriate spacers, such as mesh or corrugated spacers, between the membrane spiral. One of the two fluids - that is, the feed (and retentate) or the permeate - flows inside the wound, flattened membrane tube, while the other fluid flows through the channel containing spacers, in cross flow to the fluid in the wound membrane tube. 

Boron trifluoride ammine deposits on the walls of flask 1 in the form of a bulky, loose powder. To prevent clogging of the tubes feeding in the gases, they must be at least 7-8 mm in diameter. Gather half of the prepared substance in a drawn out test tube and seal it. 

There are a number of well-established systems for the aseptic packaging of liquids. Notable among these are those packs constructed, box form, in situ on the filling line from a cardboard, aluminium, plastic laminate sheet, such as TetraPak or Combi-box. In the TetraPak system, the packing material enters the filling machine from a feed roll the sheet contact surface is sterilised with warm hydrogen peroxide solution it is formed into a tube, and its lower end is heat-sealed across the width the tube is filled, sealed at the upper end, cut and then folded into a box shape. This produces a continuous output of filled cartons with premium utilisation of bulk storage capacity. 

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