Working of modified WT
A low suite combination WT (Figure 01) in a residence has to be manually cleaned, which can be completely eliminated by modifying the flushing system of WT (Figure 2).
The proposed modification is simple. A small tank with opening at its bottom has to be fixed to store the liquid phenol and the free surface level of the phenol will be lower than the free surface level of the water in the flush tank. The opening of the small tank is connected to the water pipe of the flush tank (connecting the flush tank opening at the bottom and bowl of WT) with a capillary tube. The end of the capillary tube is bent at 900 so that its opening is along the direction of water flow from flush tank to the bowl.
Since the pressure head of phenol is less than the water head in the flush tank, though the capillary tube completely open, phenol will not flow out of the capillary tube. It will flow only when the water flow starts in the flush tank bottom pipe. Hence, whenever the WT is flushed automatically phenol flows into the bowl along with the siphon water and cleans the whole bowl. As and when water flow stops, the flow of phenol also stops till the next flushing takes place.
Though the cleaning of modified flushing system of WT is automatic, it requires regular maintenance. Main maintenance is similar to that of maintaining the conventional manually cleaned WT.
Now varieties of toilet cleaners – liquid or solid (chemical or herbal) – are available. WT can be cleaned by using these cleaners and the toilet brush or only the Hi-Tech toilet cleaners. The flush tank, tube and the capillary tubes must be cleaned periodically.
Occasionally clogging may occur. It is due to the flushing down of unsuitable items or too much toilet paper. Flushing of large amounts of hair should also be avoided. The clogging can also occur due to lime scale formation within the drain pipe, or by overloading the stool capacity of the toilet. Stool capacity varies among toilet designs and is based on the size of the drainage pipe, the capacity of the water tank, the velocity of a flush, and the method by which the water attempts to vacate the bowl of its contents. Sometimes, three to four flushes are required to prevent clogging. Partial clogging occurs when flushing a loaded toilet.
In this water mixed with waste excrement overflows WT. However, it depends on the bowl volume, flush tank capacity and severity of clogging. For this reason, rooms with flush toilets may be designed as wet rooms, with a second drain on the floor, and a shower head capable of reaching the whole floor area. Common means to remedy clogging include use of a toilet plunger or drain cleaner.
Toilets that used water were used in the Indus Valley Civilization. The cities of Harappa and Mohenjo-Daro had a flush toilet in almost every house, attached to a sophisticated sewage system. The modern system differs only a little bit. All these are manually cleaned. The modified flushing system for the automatic cleaning WT cleans itself without any manual efforts. It is observed that the diameter of the capillary tube can be selected appropriately for saving the cleaner flowing into the bowl. This is achieved by calibration. If the capillary diameter is a higher gauge hypodermic needle can be fixed at the outlet opening of the capillary tube. Again calibration is necessary to determine the correct gauge number of the hypodermic needle. This modified flushing system can be conveniently installed in the Indian type toilets / squat toilets with flush tanks, in the lavatory sinks with flush tanks and in other such toilets/sinks with flush tanks.
The modification of the flushing system of WC may increase the system cost no more than 0.2-0.4% of the total cost of WC installation and there will be comparatively savings in the toilet cleaner. The methodical experimentation will ensure the working the modified flushing system.