Bernard Zimmerman & Olaf Griese

Electric conductivity and pH measurements in drain water of a biomeiler

This is a summary of a presentation during the 3rd International Biomeiler Conference in Leipzig in 2018.
This presentation has been transcribed and summarised by Arie van Ziel, please contact me if you'd like to extend on the text or edit something.

This talk is about an oval biomeiler build up just north of Stuttgart.

We had a perfect location right in between both our houses. In place of a planned car-port they decided to create a concrete flooring in as most an organic way as possible by adding homeopathic material.

On top of the concrete flooring a steel fence was build in the general way. For filling the biomeiler a small conveyer belt was used. With about 3-4 people inside the fence and 3-4 people outside it worked very well. The woodchips were made locally from fresh cut wood from trees that were not healthy anymore. They were ash trees that are taken by the fungal sickness that is currently spreading in Europe.

Organic horse manure was added and a bottom layer of chipped straw. The circular shape was made into and oval by using a nylon belt from a truck. Below and on top of the bottom plastic sheet there was made an outer layer of strawbales to guide the water to the drainage put. For about 3 weeks the water was pumped around on top of the system. During the buildup the top was made flat and later covered with straw for insulation.

About 3 m3 of manure was used.

The pH and the conductivity was measured from the drainage water. The pH started around 6 and went the first week to a little below 5 and on the 7th day the pH went up to 6 and stayed like that until the 15th day. The days after the pH came up to almost 8 after a year.

The conductivity went up during the first days and went slowly down again, but is still higher then drinking water. The downward trend is logical because the developing humus fixes the minerals.

The temperature went up to about 58°C and after is year it’s still 50°C, this was not monitored closely but shows a normal result.

After a year the heating system has been installed. Inside the biomeiler a triple-layered PUR/Aluminium/PEX pipe was used in three layers in paralel with a floor heating manifold with flow meters.

After a while the outside was covered in plastic and decorated with wooden planks. The plastic is almost to the bottom of the biomeiler and almost in touch with the bottom layer of plastic.

Just now after a year the connection to the heating system of the house is made. The installation is with a thermostatic controlled three-way valve and the pump directly at the biomeiler. It is not yet up and running because before winter an insulated box should be made first to prevent freezing risk.

The total cost was about € 3000,- and with reuse it would be possible to have a cost of € 700,- for the next biomeiler. The possible energy savings were not yet calculated.

Olaf has a very good insulated house with low energy use, so this is the most interesting to test the biomeiler as a heat source. The house has low temperature wall heating installed.

Bernard has an high energy use because of low insulation and standard radiators/convectors. He is installing wall heating in some rooms for use with the biomeiler.