Extended Drain Times

A drain time of at least 10 seconds has been shown to reduce dragout by 40+% over immediate rinsing.[22] Once again straightforward when processing is automated, the key to implementing this option in manual operations is to provide suitable rests for the work piece while it drains. 

This refers to the amount of time a work piece is actually in a tank being rinsed. Its effect on rinsing efficiency, and therefore its potential for source reduction, can be nearly as great as that of the previous two options.[21] Taken together, these three options provide a set of rinsing procedures which, when done well, can reduce dragout, and therefore waste requiring treatment by over 50%. 

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Because the air purifying filter removes nearly all the water and dirt, it is not essential to use any other filters. If a filter separator is installed just ahead of the air purifying filter, it will act as a ptefilter, and the life of the air purifying filter cartridges will be extended. several times. The technique has the added advantage that water is drained automatically fi om the system by a float-operated valve. 

It is also preferred where suspended solids create a high pressure drop, or dissolved gases create bubbles in the carbon bed. For a downflow or percolation system, an influent line should be installed at the top of the column, with an effluent at the bottom. To prevent the column from draining during operation, the effluent line from the last column should extend from the bottom of the column to above the top of the column. This will keep the column filled with liquid at all times during operation and prevent siphoning from occurring. 

Obviously, clogged drains are not much fun. But free-flowing ones can be. They afford fantastic opportunities for scientific conjecture and experimentation. For example, does water really spiral down the drain counterclockwise in the Northern Hemisphere and clockwise in the Southern Certainly, hurricanes and tornadoes spin in opposite directions above and below the equator. This is due to the so-called Coriolus effect, which is based on the fact that the earth spins in an easterly direction at a speed of about a thousand miles per hour at the equator. As we move north or south the speed decreases, since less distance has to be covered in the same time. Now, imagine that there Is a gigantic bathtub extending from the equator to the North Pole. The water near the equator will travel east much faster than the water near the North Pole. If we pull the plug, the water will spin down the drain counterclockwise due to the... 

Unless otherwise specified standard development time for all the paper developers are 1 i minutes for RC (i.e., 1 minute 20 seconds with a 10 second drain) and 2 minutes for fiber-base (1 minutes 50 seconds with a 10 second drain). You can extend or shorten the time to suit individual images. 

Drying. Drying is an optional step. One factor in whether drying should be done is the time period before the next use of the equipment. Equipment that is to be used immediately (within a few hours) may not have to be dried, particularly if the equipment is effectively drained to minimize any dilution effect of residual rinse water or solvent. However, the effect of residual water on microbial proliferation during extended storage is a significant issue. Options for drying include heated (and optionally filtered) air and the use of a final alcohol/water rinse. The final alcohol/water rinse may also further reduce the bioburden due to the antimicrobial action of the alcohol. This use has to take into consideration the flammability of such a mixture. 

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