Cleaning and liquid contact with solids – Processes – Work handled in bulk or groups
Patent
1992-07-23
1994-10-18
Dean, Richard O.
Cleaning and liquid contact with solids
Processes
Work handled in bulk or groups
134 18, 134 255, 134 34, 134 56D, 134 57D, B08B 302
Patent
active
053564839
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
This invention relates to a process for the continuous machine-washing of institutional crockery in an institutional dishwashing machine comprising a wash zone and a following rinse zone, in which the soiled crockery is successively sprayed with wash liquor in at least three wash zones fed from separate tanks by means of circulation pumps and a system of spray nozzles, the wash liquor cascading preferably from the last to the first tank on the overflow principle and the detergent concentration in the wash liquor first being separately established in the individual tanks by predosing and, after the start of the washing process, being maintained by after-dosing of detergent and inflow of fresh water into the last tank, and in which so-called thorough washing is optionally carried out at relatively long time intervals with a distinctly increased concentration of detergent in the wash liquor.
RELATED ART
One such process is known from the prior art and is often applied in institutional dishwashing machines. In this process, the concentration of detergent in the individual washing tanks is normally kept substantially the same except for so-called thorough washing which is normally carried out, for example, once a month with an increased concentration of detergent in the wash liquor. Despite this thorough monthly wash, however, the first signs of so-called accumulated starch deposits on the dishes can be seen after a few days.
Accordingly, it is proposed in DE-OS 37 07 366 to install an additional spraying system for this process and, using this spraying system, to spray highly concentrated detergent mists containing 100 to 1000 g detergent per liter water onto the dishes in a wash zone. Although this process improves overall dishwashing performance, it is still attended by disadvantages. Thus, it is necessary on the one hand to provide an additional spraying system which complicates and adds to the cost of institutional dishwashing machines. On the other hand, on account of its high alkalinity, the detergent solution sprayed in such high concentrations is a major potential hazard to the machine operator, not least because of the staying power of the fine mist. For example, in the event of malfunctions of the machine, the machine operator can come into skin contact with the highly alkaline detergent solution or may even be splashed in the eye with detergent solution with the resulting danger to eyesight. In addition, where highly alkaline detergent solutions are used, special and additional measures have to be taken to protect the dishwashing machines against corrosion.
The object of the present invention was to provide a solution which would enable the dishwashing performance of conventional processes to be increased with no increase in overall detergent consumption and without having to use detergent solutions of extremely high concentration.
SUMMARY OF THE INVENTION
In a process of the type mentioned at the beginning, the solution provided by the invention is characterized in that a main component stream of wash liquor amounting to more than 50% and preferably to more than 75% of the quantity of fresh water flowing into the last tank is branched off from the last tank and is fed directly to the third-to-last tank and/or to a tank situated further to the front, in that the remaining wash liquor passes through the tanks as a secondary component stream, cascading at least from the middle and/or penultimate tank, and in that a detergent concentration increased by at most the factor of the division ratio of fresh water to secondary component stream is adjusted in the wash liquor in at least the middle tank and/or the penultimate tank, the after-dosing of detergent taking place in this tank only.
It is possible by this process to establish a distinctly increased concentration of detergent in the wash liquor--compared with conventional processes--in the wash zone of an institutional dishwashing machine (in the middle tank of a three-tank machine) without at the same time increasing
REFERENCES:
patent: 2619097 (1952-11-01), Bromssen
patent: 3896827 (1975-07-01), Robinson
patent: 4076554 (1978-02-01), Weihe
patent: 4319930 (1982-03-01), Yano et al.
patent: 4375993 (1983-03-01), Stevens et al.
patent: 4379031 (1983-04-01), Krothiewicz et al.
patent: 4561904 (1985-12-01), Eberhardt, Jr.
Rings Friedel
Saalmann Guenther
Schaab Udo
Schuster Thomas
Selbertinger Josef
Chaudhry Saeed T.
Dean Richard O.
Henkel Kommanditgesellschaft auf Aktien
Jaeschke Wayne C.
Ortiz Daniel S.
LandOfFree
Process for the continuous machine-washing of institutional croc does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for the continuous machine-washing of institutional croc, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the continuous machine-washing of institutional croc will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2369720