Sewage refinement

Vertical whirlpools ... Pipe system ... Nozzle ... Reagent pipe ... Cleaning rivers


Get compost toilet ! My idol is charcoal (biocarbon) 
because it looses not so much 
carbon dioxide in refine process

~~ We have seen big, expensive and not so nice sewage plants.
Sewage has been refined in the developed countries for a couple
of decades. But minerals of food, espesially phosphore have not
yet been transported back to arable lands for cultivation. The
demand of phosphore will increase soon.
Many rivers would have not been cleaned. It can be their turn now.

The best way is to make compost and to fertilize plants.

Could there be a different perhaps cheaper and more unnoticeable way to deal with sewage? I claim there is. The walls of a sewage plant are solid matter: concrete, steel. In the plant presented here there are no solid walls at all. The sewage stays put and is refined without having to build any walls in nature underwater. The principle is the same we have seen at the doorways of supermarkets in winter when a rising air current is produced there. The air current prevents the warm air from rushing out.

Bit !
In my method rising water prevents the still dirty water from breaking out to the middle of a lake, for example,
before it has time to be refined. In my method the water is set into a revolving motion with the help of small air
bubbles.The water revolves as vertical whirlpools. There are several of these whirlpools thereby
preventing the sewage from escaping to the middle of the lake. Instead it slowly becomes oxidized,
turning into inorganic and less harmless compounds
(see illustration below) such as water, carbon
dioxide, nitrogen gas, unsoluble phosphates by ferrous II sulphate. A mere aeration is not enough. Before
that the large particles must be filtered from the sewage. In connection with the aeration substances that
eliminate compounds enhancing eutrophication, such as phosphore for example, must be added to the water.
Furthermore, in the aeration process we must add appropriate microbes to the water in some whirlpool to
speed up the biological process.


Vertical whirlpools
Revolving sewage The location for the refining process is usually a bay in a lake or sea, not too sloping. The waste goes down to the bottom and stays there. Since the area needed for this process is big, not much solid matter piles up on the bottom in a lifetime, but that can be dredged away if necessary. In my opinion there's no need generally for dredging. From the above follows that you can't even see the place of the refining process. It is true that the water near the shore of the bay is dirtier than in the middle of the lake where the water is clear and clean. You might perhaps notice, while rowing a boat, a little bubbling in certain places. But you notice nothing from a motor boat or a sailing-boat. There is a shed on the water-front and a little humming can be heard from there. The air- and active sludge pumps are in operation there thrusting air, active sludge, ferrous sulphate solution and maybe ozone in precisely the right amounts in the right places under the water. The air bubbles must be small enough. The right size of the bubble may be in the region of 1mm3.
The purpose of the air is two-fold: air must be dissolved in the sewage 1. to oxidize the impurities of the water and part of the air maintains the 2. revolving motion of the water. The suitable size of the bubble may be such that half of it is dissolved and half keeps up the revolving motion, in other words rises to the surface of the water. The revolving motion can be very slow, something like one hour per revolution, so that not much energy is needed to maintain it. The water does not escape to the middle of the lake from a rotating motion, especially when there is no wave motion. Only that amount of water goes to the middle of the lake which comes out of the waste pipe, perhaps even less depending on evaporation. If there are high waves, then the sewage goes faster to the middle, but the rotating motion slows it down crucially.


Pipe system


Purify field of sewage

The pipe systems are often at different depths in the water. If the difference in depth is great you must use several different air pumps each of which has a different pressure output. The same pipe must be placed at the same depth. For example, if A lies at 10 meters' depth, B at 20 meters and C at 30 meters, there must be three different pumps on the same shaft of the electric motor, one for each depth. The best distance between the pipes is the sum of pipes next to each other. Then the whirlpool is nearest to the shape of a circle and thus uses the least energy. In the example above the distance between B and C is about 50 meters.

The underwater pipe system surrounds the place where the sewage is discharged. In the picture above the innermost pipe aerates the sewage without any chemicalization. It is only an air pipe and air bubbles come out of it. Pipe A consists of two pipes on top of each other. The lower and bigger pipe is a similar air pipe than the others but on top of it there is a smaller pipe through which active sludge, a compound of water with a certain bacterial strain, is pumped. The bacteria attack the biological waste and decompose it making it inorganic. The bacteria must naturally be cultured somewhere. The bacterial strain depends on the temperature, too, not only the composition of the sewage. In different seasons you may have to feed different bacteria into the pipe. Industrial wastes need different kinds of bacteria than settlement wastes, and mixed wastes still different. Pipe B embodies an air pipe and a smaller pipe on top of it through which ozone is transmitted. Ozone decomposes those substances that the bacteria and aeration cannot. Pipe C embodies an air pipe and a smaller pipe on top of it through which the aqueous solution of ferrous sulphate is transmitted. The purpose of the ferrous sulphate is to precipitate phosphore, which makes the water system eutrophic, to the bottom. Ferrous sulphate and perhaps other reagents, are transmitted through the pipe, either simultaneously or in succession.

The air pipes contain a large number of small holes through which the air passes into the water. In order to get the greatest number possible of the smallest holes possible with the smallest possible machine power, one must place appropriately shaped nozzles in the pipe's holes. My guess for a nozzle shape is in the picture:




Nozzle Air bubbles oxidize sewage

The nozzle is fastened to a hole, with a diameter of about one cm, in the pipe, and the hole's diameter is about one mm. One can of course consider a mere air pipe, with holes bored in it, but will such a pipe produce bubbles small enough? The suitable metal for the nozzle is copper because it prevents the nozzle from becoming overgrown.

When a power cut stops the air pumps they cannot generate air any more. Then the leaking of air through the pumps is stopped by closing the return of the air automatically with the help of valves. If these power cuts occur often, one must clean the nozzles of the pipe, sometimes either by diving or lifting the pipe to the surface. A bottom valve in the deepest point of the air pipe can help empty the air pipe of water after a power cut. The valve would have two flaps, one is a ball containing air. The ball would close the exhaust valve when the water has left the air pipe. The pressure in pipes must secure someway constantly..


.Uppermost reagent pipe


Above you can see a cross section of the pipe system. The concrete block lies lowermost, to which the air pipe is attached The blocks appear at certain intervals, for example of 10 meters, and their function is to secure the pipe in its place and in the right position. There are air nozzles on the sides of the air pipe at certain intervals (0,2-0,5 meters). Uppermost is the reagent pipe attached on top of the air pipe. Through the holes of the reagent pipe gush out active sludge, ozone or perhaps chemical reagents against heavy metals which the rising water catches with it and takes round, mixing the reagents evenly in the body of the water.


Fish will return
The cleaning of big rivers

A great number of the rivers in the world are very polluted and hundreds of millions of people live on their shores. For example the Ganges: 400 million people live close to the river. A fast-flowing river aerates itself to a certain extent whereas a slow-flowing river does not really become clean. From the point of view of people's health it would be important to try to clean these rivers. After all, dirty river water spreads many contagious diseases, such as cholera. The importance of rivers would greatly increase because of use of water, recreation and return of fishing. The river would change from a sewer to a water pipe; more poetically expressed, from the valley of death to the source of life. For the cleaning of rivers one can use a similar method as presented here.

The mechanical removal of large particles is more troublesome than presented above because there are numerous sources of refuse. One can try to take out refuse that is already there in the rivers by nets as if fishing, but it is difficult because of the river traffic. Some kind of inclined conveyor belt or rather a conveyor net could collect the refuse on the surface of the water and bring it ashore. I guess there is no good solution.

On the other hand, biological and chemical waste can be destroyed through aeration, bacteria, oxidization, and precipitation:

Häränvirta / Äänekoski
1. Aeration: An air pipe with holes is laid across the river along the bottom. The small air bubbles dissolve in the water and start the biological oxidization.

2. Active sludge: Suitable bacteria are fed, with the help of air bubbles, into the river water with pipe systems that run along the bottom of the river a short distance from the previous place downstream.

3.Ozonification: The ozone-rich air coming from an underwater ozone pipe oxidizes especially many industrial chemicals. Ozone resolves quickly and will not be harmful anymore.

4.Chemicalization: The nutrients and wastes, especially those containing phosphore, that are left, are turned with the help of, for example safe ferrous sulphate and perhaps other reagents into an indissoluble form, and they descend to the bottom of the river. These four pipe systems probably lie along the distance of one kilometre so that one sewage plant could treat them.

If it is a big river, thousands of kilometres long and slow-flowing, the cleaning process of the water must be repeated several times and at intervals of a few hundred kilometres. The sand carried by the river and the heavy river traffic may be dangerous to the pipes of the sewage plant. For motivational reasons it is advisable to build the plant on the border of a state or province as the river enters a new administrative district.
Citizens are also motivated to cleanliness, as: "Get compost toilet !"

Bottom sediment will be dredged and it will fertilize earth for food production. Especially phosphorus is most important fertilizer, but bad for lake systems and rivers. Phosphorus can be in the bottom silt thousand years or be dredged every year before the monsoon rain to arable lands for use. It is important that the phosphorus and perhaps heavy metals too in second location remain insolube in the bottom silt before dredging.

Next Desalination
Tapani Hakonen
Äänekoski Finland Realm