ES2334479B1 - SEPTIC FOSA OF LOW MAINTENANCE. - Google Patents

Abstract

Low maintenance septic tank.

The invention is an improved septic tank, with a airtight container where sewage accumulates, performing a secondary treatment. The deposit is compartmentalized in three enclosures communicated by the bottom, leaving an air chamber at the top where it is performed the combustion. The wastewater connected to the pit is the corresponding to the bathroom, kitchen, washing machine, sink, etc. He Maintenance is almost non-existent for fifteen years. The industrial application of the invention will be in the construction of homes, hotels, housing developments, etc.

A low septic tank is claimed maintenance characterized by a compartment divided into three enclosures The first of slightly larger size and the last of Slightly smaller size. The three enclosures will respect certain proportions with respect to the total size. This pit septic has a combustion chamber of fifteen centimeters and the Residence time will be twenty one days.

Description

Low maintenance septic tank.

Technical sector

Domestic wastewater treatment.

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Prior art

A septic tank is an airtight container closed where sewage accumulates and where they are given a primary treatment, separating solids from water black

The septic tank is the most economical method available to treat urban sewage. But for what can function properly, you must choose the septic system suitable for population size, and should be given a periodic maintenance.

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Operation of the Septic Well

Eliminate solids by accumulating sewage in the tank and by allowing part of the solids to settle in the bottom of the tank, while the floating solids (oils and fats) rise to the top.

To give solids time to settle, the Tank must retain sewage for at least 24 hours. Some of solids are removed from water, some are digested and others are They remain in the tank. Up to 50 percent of the solids that are accumulate in the tank decompose; the rest accumulates like mud at the bottom and must be pumped periodically from the tank.

Septic tanks remove solid matter by decanting, by stopping residual water in the tank, which allows the sediments sink and the impurity layer floats. I dont know they need biological or chemical additives to help or accelerate the decomposition.

The silt continues to accumulate at the bottom of the septic tank while using the septic system, without any intervention. Properly designed wells have space safe for the accumulation of at least three years of silt. When silt level exceeds this point, sewage has less time to separate solid matter from water before leaving of the tank, so the process ceases to be carried out effectively. If silt builds up for too long, none occurs solid matter separation from water and sewage out directly. To prevent this, the tank has to be emptied of silt, usually with a pump of a special vehicle for emptying of septic tanks.

The deadline for emptying a Septic Tank It basically depends on:

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tank capacity septic

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amount of wastewater (related to the number of family components)

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solid matter volume inorganic in wastewater.

The most important advantages of the invention are the low maintenance of the installation and the absence of extraction sludge, avoiding the economic cost of tank trucks with motor pumps with the consequent discomfort from noise and odors pestilents, and on the other hand, also the excellent water quality treated, suitable and suitable for irrigation due to its components minerals

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Explanation of the invention.

The invention is an improved septic tank because to dimensional and geometric design. It consists of a container airtight where sewage accumulates and where they are given a secondary treatment -improvement of water quality-, also achieving non-existent maintenance for at least fifteen years - the solids not being removed.

To achieve these results the design of the septic tank must be performed with the following definitions and parameters (these values have been obtained through the different experiments that are explained in section f and ensure the achievement of the objectives):

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The design parameters of the pit tank They are:

\ circ Time of home:

21 days

\ circ Water supply per inhabitant and day:

135 liters per inhabitant and per day

\ circ Water flow residual (evaporation reduction in {} \ hskip0.3cm {} \ hskip0.25cm laundry, shower, watering pots, around the fifteen%):

\\ [2.1mm] 115 liters per inhabitant and per day

\ circ Chamber of combustion:

15 centimeters between coronation of the walls of separation of the enclosures and the slab  higher.

With the provision of water per inhabitant and day, the number of people who will be connected to the debug system and the residence time of the water in the pit the volume is calculated Total deposit of the pit. The depth of the pit will oscillate between 3 and 4 meters at the discretion of the designer depending on the hardness of the geological layers of the terrain, this is not a parameter fundamental in the definition of the septic tank for achievement of the objectives. The proportion between length and width of Deposit will be between 1.3 and 1.5.

The deposit will be divided into three enclosures, the first of a slightly larger size for the accumulation of the initial mud, and the last of smaller size for the final reassurance of the outlet water. The three enclosures they will be consecutive, and their proportions with respect to the total volume calculated will be:

First enclosure between 35 and 40% of the total.

Second enclosure between 32% and 35% of the total.

Third enclosure between 28 and 32% of the total.

By choosing the volume proportions of the three enclosures must be met that the sum of the proportions is 100%

These enclosures will be communicated by the party bottom with three holes 0.3 meters long by 0.2 meters height 0.5 meters from the floor of the tank, spread evenly along the separation wall between enclosures. Communication from the second to the third enclosure, in addition to the three holes in the bottom, will also have three holes of 0.30 meters long by 0.2 meters high 0.5 meters from the ceiling of the deposit.

The three enclosures will leave a camera of combustion at the top of 0.15 meters between the roof of the reservoir and the surface of the liquid, where the anaerobic combustion of biodegradable matter in the form of gas that remains after the fermentation of the wastewater. This camera it will be saturated with organic gases (methane, nitrogen, and monoxide and  carbon dioxide mainly) and with a great defect of oxygen. Due to residence time, organic matter Biodegradable in a liquid and solid state passes into a gaseous state.

As explained in the definition of the parameters, this is the combustion chamber height with the which was experienced in the examples of section f that met the objectives of low maintenance and absence of extraction of sludge for at least 15 years.

Each enclosure will be provided with a top cover of registry. These covers will be sealed with a hydraulic closure to prevent the release of bad odors.

Water inlet and outlet pipes are adapt to the flow of treatment and the slope of evacuation of the water. There will also be a 0.05 meter pasamuro for a Light aeration in designs of up to 200 people.

Inlet water conduction will be a 0.2 meter diameter pipe (enough for debugging of up to 200 people), this tube will be introduced in the first enclosure on one side and descend by an elbow and prolongation of pipe anchored to the wall to discharge 0.3 meters from the ground of the deposit. Do not neglect the placement of a previous siphon to ensure tightness with respect to odors.

The water outlet pipe will also be a 0.2 meter diameter conduit that will collect water at 0.2 meters of the tank floor on the side opposite the tube entrance of the third enclosure, through a pipe anchored in the wall and an exit elbow.

The wastewater connected to the pit will be those from:

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Bathroom, Water, sink, shower.

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Kitchen: Washing machine, sink, dishwasher.

To prevent the formation of an upper layer in the pit that delays combustion, the presence must be excluded from:

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Oil vegetable and animal fat whose origin is mainly from the food preparation. We must separate this residue by its high polluting effect

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Oil, grease or fuel derived from Petroleum.

To achieve this, a work of awareness of the inhabitants of the house or urbanization connected to the septic tank, with informative talks, posters of prohibition and information, visits to the purification facility, and mainly with deposits enabled for the collection of these residues (oils and fats), such and comma already have many cities of Spain.

To avoid obstructions of the pipes and of the system in general, you must also avoid entering the network of solid waste sanitation (including plastics, compresses, condoms, sand, ear sticks, etc ...).

To achieve this, the days of awareness and training of users of the network of sanitation, in addition to placing a grating grid prior to the well as a guarantor of security for obstructions.

If these water conditions are met from entry -which will contribute little or no inorganic matter-, and with the pit design parameters described on page 4, it is not sludge removal necessary for at least 15 years. This fact It is the basis of low maintenance because there is no need to be emptying it constantly.

For the calculation of the endowment have been used real consumption data in homes with water meter.

50 m 3 / year, per person: 135 liters / day

To clarify the explanation of the invention we propose in the drawings the example of a septic tank for 15 people.

Description of the contents of the drawing

Geometrically and dimensionally defined enclosure shapes, along with water inlet pipes wastewater, purified water outlet and aeration, and also communications and openings necessary for the correct operation of the treatment in the septic tank by combustion Low maintenance anaerobic designed for 15 people.

Figure 1 is a longitudinal section for locate the location of the pit (1) with respect to the dwelling or urbanizations (2), always underground and at the distance that want or believe convenient. A siphon arc is also drawn conventional (3) placed at the desired distance from the House.

Figure 2 is the plan view of the pit from the ground The dimensions correspond to a designed pit for 15 people The dimensions are 5.20 meters in length and 4.00 meters wide. The plan position of the log covers of size 0.40 meters by 0.40 meters (1), of tube of diameter 0.20 meters (2), and the outlet tube of  diameter 0.20 meters (3). Also the location in a corner of the upper floor of the aeration pipe with a diameter of 0.05 meters (4). The outer walls (5) have a thickness of 0.30 meters, and the interior separation walls between enclosures (6) have a thickness 0.15 meters. All enclosures have an interior width of 3.40 meters. The first enclosure (7) has a length of 1.60 meters The second enclosure (8) has a length of 1.40 meters, and the third (9) has a length of 1.30 meters.

Figure 3 is the view of a section Longitudinal septic tank. The sectional position is observed of the log covers (1) of 0.40 meters in length, of the tube entrance (2) whose coronation is a minimum of 0.15 meters from the forged roof, that is to say it will be submerged by the liquid and whose end will be 0.30 meters from the ground, the outlet tube (3) whose coronation is also a minimum of 0.15 meters from the roof of forged and whose starting point will be 0.20 meters from the hearth, of the aeration tube (4) in an upper corner of the floor which covers the third enclosure, of the first communication holes to the second enclosure (5), are three holes 0.3 meters long by 0.2 meters high at 0.5 meters from the tank floor, evenly distributed along the separation wall between enclosures Communication from the second to the third enclosure, in addition to the three holes in the lower part (6), will also have three holes (7) 0.30 meters long by 0.2 meters high at 0.5 meters from the roof of the tank. The combustion chamber in the upper part of the floor (8) is 0.15 meters high. The exterior walls (9), the floor (10) and the floor (11) have a thickness of 0.30 meters, and the interior separation walls between enclosures (12) have a thickness of 0.15 meters. All the enclosures They have an internal width of 3.40 meters. The first enclosure (13) It has a length of 1.60 meters. The second enclosure (14) has a length of 1.40 meters, and the third (15) has a length of 1.30 meters.

Statement of an embodiment of the invention. Examples and references

The execution of a septic tank consists of realization of a buried deposit with the corresponding water inlet and outlet pipes.

For the construction of the pit described in the drawings it is necessary first to perform an excavation of larger than the pit size, with slopes of excavation adapted to the coefficient of friction of the land. In firstly a land regularization will be carried out with low strength concrete, on which the floor will be built of dimensions 5.20 meters in length, 4 meters in width and 0.30 meters high. The necessary iron will be calculated according to the current structural regulations, leaving starting irons of the walls.

The outer walls will be lifted with double-sided formwork, also leaving the starting reinforcement for compartmentalization walls and grommets for inlet and outlet pipes. Your design will also meet the current structural regulations. When making the walls of compartmentalization will leave the drawers corresponding to the communication holes to avoid subsequent drills. Be fill the side holes of the wall ensuring a good soil compaction. Finally the slab will be executed with formwork and interior struts if the design light does not allow a forged vaults. Prior to concreting, the manhole covers, and the pasamuro for the aeration tube. One time Once the civil works are finished, the polyethylene pipes of water inlet and outlet with plastic washers or stainless to prevent corrosion.

There are several operating experiences of This septic tank design:

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House of Field in Es Molí (municipality of Cala Ratjada. Mallorca. Balearic Islands), designed for 10 people, in operation since 1998 to this day.

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Detached house in the urban area from Cala Ratjada. Majorca. Balearic Islands, designed for 10 people in operation from 1965 to 1985. In 1985 the City Council connected the housing to the urban network.

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hotel in Palmanova in the municipality of Calviá. Majorca. Islands Balearic Islands, in operation from 1960 to 1972. This hotel had 400 places, plus 100 people on staff. The design was made for the time of maximum occupation was 500 people in the months of July and August. The septic tank stopped working when the City Council due to urban planning and for legal reasons, connected the sewage from the area to the network urban, in no case due to deficiency of the operation of the pit.

In all three cases it has been verified in time Septic tank operation three basic improvements:

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Absolute absence of extraction of sludge, avoiding the economic cost of tank trucks with motor pumps with the consequent discomfort from noise and odors pestilents

\ sqbullet

The cost of emptying a septic tank ranges between 90 and 150

 \euro 

/ annual (prices updated in 2007, on the island of Mallorca).

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Excellent water quality, suitable and suitable for irrigation due to its mineral components. The analysis of the period of which one of the year 1970 is preserved, determine the water suitable for showering, with the absence of ammonia, slight indications of nitrites, and slight indications of coliforms. The analysis was performed by pharmacist Carlos Antich, of Cala Ratjada

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He water was used to irrigate the hotel gardens and the houses, without causing any discomfort of odors or problems of sanitary origin

Industrial application of the invention

It has no application in the chemical industry or livestock, but in the construction of homes, hotels and urbanizations

Claims (1)

1. Low maintenance septic tank for the purification of domestic wastewater, characterized by a compartmentalized deposit in three consecutive rooms whose total volume will be calculated based on the daily treatment flow, multiplied by the 21 days of residence time of the flow. The depth of the pit will range between 3 and 4 meters. The ratio between length and width of the tank will be between 1.3 and 1.5. The three enclosures will have proportions with respect to the total calculated volume of: First enclosure between 35 and 40% of the total. Second enclosure between 32% and 35% of the total. Third enclosure between 28 and 32% of the total. By choosing the volume proportions of the three enclosures must be met that the sum of the proportions is 100% The combustion chamber of the septic tank, located between the coronation of the separation walls of the enclosures and the upper floor will be 0.15 meters.