What is a dry toilet?

A dry toilet or ecological toilet is one in which no water is used for waste management, giving the possibility to avoid water and soil contamination. In addition, these systems process human waste and transform it into compost, a natural fertile fertilizer that serves to enrich the soil. These toilets do not use water and are not connected to the sewage system.

What is Permapreta®?

Permapreta® is a comprehensive and efficient dry toilet and/or composting system, which is the result of a long search for the optimization of these systems. With Permapreta® you can provide a solution to the entire management of feces and urine; and organic waste. Its main strengths are the elimination of odors, the safety against pathogens and the superior extraction that allows Permapreta® to be incorporated in the construction and architecture of buildings.

Why use Permapreta® instead of a traditional toilet?

Permapreta® applies the principles of PERMACULTURE, does not use water to operate and optimizes the biological decomposition of our waste generating a high quality humus.

How does Permapreta® work?

It consists of the separation of urine and feces, using the urine on one side for its revalorization as fertilizer and the composting of the feces by means of worms and microorganisms by a continuous vertical flow, in order to obtain a compost of high biological value. Attached PDF Dry toilet worm humus by continuous flow. Download user guide: Baño seco hummus de lombriz por flujo continuo.

What happens to the stool?

The feces or depositions are converted into vermicompost thanks to the composting process inside the bath. This resulting material has optimal characteristics for use in the regeneration of degraded soils.

What is done with the urine?

The urine is stored in a tank where it rests for 30 to 180 days, thus eliminating possible pathogens and allowing it to be used as fertilizer, since it contains high concentrations of plant nutrients including nitrogen (N), phosphorus (P) and potassium (K).

How is humus extracted?

Compost is always extracted from above if it is buried, with the help of an auger or by suction with a liquid vacuum cleaner of 15 to 30 liters of volume (https://www.kaercher.com/es/home-garden/aspiradoras-para-suciedad-solida-y-liqui da/wd-3-home-16281200.html), depending on the access to electrical energy in the place where it is installed. When it is installed on a structure and is accessible, gates are installed to widen the access routes to the bottom of the hopper.

What organic matter can be used as bedding and where can it be obtained?

The initial bedding is based on paper, straw or semi-decomposed domestic organic matter, free of insect clutches, which will retain the first depositions. After one month we provide the first worm bedding. We supply Permapreta® if necessary, but worm castings and bedding from other suppliers or garden composters can be provided, taking care that they are free of fly or other flying insect droppings.

How is a Permapreta® dry bath maintained?

Its maintenance is simple, it only requires following the protocols recommended in the Installation and Use Manual that you can consult and/or download in the OPERATION section. It is essential to follow these guidelines for the correct evolution of the composting process.

What must be done to keep the worms healthy and alive?

To keep the worms healthy and alive, organic matter is provided for them to feed and reproduce. This organic matter is our feces, bokashi, efficient microorganisms, some straw, toilet paper, pyrolytic charcoal and some food scraps processed with grade 1 bokashi systems. We provide in the first purchase a preparation with the right mix of these materials, to add them every time we make a deposition.

What temperature do the worms need?

E. foetida lives between 0º and 43º, being more efficient its activity and reproduction in temperatures between 20º and 25º. Therefore, to optimize the process it is advisable to protect the Permapreta® from extreme temperatures.

How often do I have to extract the humus? From the beginning of the use of Permapreta® it takes about two years to obtain the first compost, then it can be extracted once a year.

How do I clean it if I can’t pour water?

Instead of using biocides such as bleach or ammonia, we recommend the use of natural products for maintenance and cleaning. For example, eMC cleaner (based on microorganisms and essential oils), vinegar, natural soap or lemon.

Can the Permapreta® be filled and clogged?

If the process is NOT carried out according to the recommended indications, the composting process may stop and cause an excess of unprocessed material. It would be necessary to recover the proper protocols and, perhaps, to add worms again. It is always possible to intervene and manage from the upper openings of the system.

How long does it take to install and start using?

The installation time depends on whether it is done in a previous construction or a new one, but it is simpler and cheaper than installing a sewage treatment plant.

What are the possible locations for the system?

The chamber can be buried or anchored on a metal structure or building site where it is kept elevated, allowing its installation on second floors.

What ventilation systems do we offer?

Hybrid air extractor system (wind and magnetic motor) and axial fan ventilation system.

What is the consumption of the extractor hat with a magnetic motor?

When there is sufficient wind, the system generates little or no energy consumption. The power consumption is comparable to that of an LED lamp (3 W). The installation of the extractor is similar to that of any wind extractor but it must supply a 12 volt DC source with 1A current capacity through the connector provided. It is suitable for use with solar panels or wind turbines.

What is the consumption of the axial fan air extraction system?

The consumption of an axial fan ranges from 10 to 15 W.

How is odor generation avoided?

The hybrid air extractor system that accompanies the installation takes advantage of the structure of the conventional wind extractor which, by means of electrical action and electronic control, keeps the extractor in operation in the absence of wind,ensuring air renewal at all times with minimum consumption and making efficient use of electrical and wind energy.

How to avoid the entrance and reproduction of insects?

– Keep the toilet lid down when not in use.

– Place a mosquito net at the ventilation outlet before the extractor hood.

– Do not add fruit or half-decomposed food that can carry insects (this type of food should be previously composted and fermented in a bokashi bucket).

– It is advisable that the bathroom has mosquito nets on its windows.

What is the maximum number of people that can use the Permapreta® in a day?

Permapreta® has two models: one of 500 liters of volume that allows the average use of up to 3 people per day and another model of 750 liters of volume that allows its daily use up to an average of 6 people.

Are there any contraindications with the use of dry baths when taking medicinal treatment (antibiotics, etc.)?

There is no impediment in using Permapreta® in these cases, it will self-regulate the bacterial population.

Is the resulting humus useful?

The resulting humus material has a high biological value, very suitable for use in reforestation, agriculture and soil rehabilitation. Its use in home gardens and urban public spaces should be avoided.

Can compost from toilets be used in the vegetable garden?

Humus from public dry toilets is not recommended for use in vegetable gardens. In case of using the one from a family without references of infections by pathogens or parasites, its use can be made counting on a good previous superficial solarization and never for production of leafy vegetables. But it is an avoidable risk.

Can a child or a baby fall through the toilet hole?

With children and babies precautions should always be taken, although it is quite difficult for this to happen. Children’s adapters can be fitted as in any normal toilet. However, the toilet seat of any Permapreta® should always be lowered.

Find Us:

Polígono el Pont.
Avenida España nave 32

Call Us:

(+34) 629034278
(Jose Vicente)

(+34) 642330223

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