Fertilizer

Worldwide, approximately 180 million tons of phosphate are mined each year, of which about 90% is used in the production of fertilizers.
Phosphate is irreplaceable in fertilizers. There are several different types of fertilizers currently used that contain phosphate:
  • Universal Fertilizers

    The so-called universal fertilizers are liquid or solid complete fertilizers. In any case, they contain the three main nutrients nitrogen (N), phosphorus (P) and potassium (K). In addition, there is a selection of other macronutrients and trace nutrients; the exact composition varies somewhat from product to product. Most universal fertilizers contain a balanced nutrient composition. This means that the main nutrients are included in approximately equal proportions.
  • NPK fertilizers (nitrogen-phosphorus-potassium fertilizers, often with additives like calcium, magnesium and sulfur)

    1. Mineral fertilizers: the plant nutrient is present in these fertilizers in its pure, mineral form as a "nutrient salt." Many mineral fertilizers are coated so that the crystalline structure is no longer visible. The raw materials are mined from fossil deposits.
    2. Organic fertilizers: The plant nutrient is present as a component of an organic compound. It must be released from the organic structures by the plant or soil before it can be absorbed through the roots. This process involves many chemical reactions in the soil and especially in the root zone. It takes a little longer for the nutrients to become available to plants.
    3. Organic-mineral fertilizers: Both mineral and organic components are used in these fertilizers, sometimes different compounds for a single nutrient element. The purpose of this is to take advantage of the different rates of action and properties of the compounds.
  • Fertilizers with a predominant phosphate content

    Fertilizers with a predominant phosphate content are mainly used in agriculture, since there is usually already enough phosphorus in our garden soil.
    A phosphate fertilizer with a high phosphate content is, for example, diammon phosphate (DAP). This consists of nitrogen as well as phosphorus and forms a light brown granulate. DAP contains 46% highly concentrated phosphate.
Two farmers reveal their views on phosphate fertilizers:
Here you can read the assessments and experiences of farmers on this topic:

Interview with Phillip Krainbring

Phillip Krainbring works as a farm manager on an arable farm in the Magdeburg Börde. Even as a child, he was enthusiastic about agriculture. For us, this conversation was of great importance, as it gave us the opportunity to perceive our project from a farming point of view.
At the beginning of the discussion, the importance of phosphate was once again emphasized by the farmer. Nitrogen-phosphate fertilizer is most used alongside organic fertilizer, such as manure. Phillip Krainbring focused above all on the tense political situation of fertilizer use. Particularly important here is the Fertiliser Ordinance, which regulates the application of the amount of phosphate.
He also cited the Russia-Ukraine conflict as the cause of price increases for phosphate fertilizers. At this point, our project would provide a remedy, because local production of phosphate in Germany would lower the price. Farmers are aware of the problem of washing out phosphate. However, not all regions of Germany are equally affected, which is why a distinction within the Fertiliser Ordinance is necessary. Through our project, at the end of which is the production of polyphosphate, offers the advantage that a granular fertilizer can be applied to the fields. This would be much less odorous, partially removing the social pressure from farmers. There would then be fewer complaints about odor nuisance.
Phillip Krainbring encouraged us in our actions as he also attaches great importance to the phosphor issue in agriculture and nutrition for the growing world population, respectively. He said that an economical phosphate-fertilizer in the form of powder would meet the requirements in his area of application the best. Furthermore, he sees a great future in the recycling of phosphate, because its a finite resource and the agriculture depends on it. All in all, he thinks our project to be very promising and the solution to many problems. We were highly motivated to pursue our approaches as the polyphosphate production at the end of our production cycle is exactly what the farmers need. The dialogue with Phillip Krainbring turned out to be essential for our product development.

Interview with Tim Riedling

To get an expert opinion on the use of phosphate in agriculture, we had the chance to interview a farmer. Tim Riedling works on a farm that breeds both plants and animals. He told us that phosphate plays a big role on this farm. On the one hand, it is used in the specially mixed fertilizer for silo maize, but it is also added to the animal feed for dairy cows. He also said that people working in the agricultural sector are aware of the major problem of phosphate oversupply and the resulting environmental damage, as well as the shortage of phosphate. He also sees a very big problem in the future if a method to recycle phosphate is not found soon. According to him, the cultivation of food and the resulting yields would then drop significantly, so that a global famine cannot be ruled out. He was therefore very interested in our project and confirmed to us that there would be a great deal of interest in agriculture. In addition, our product, the pure phosphate in powder form, is very good and easy to use for farmers.
As can be seen from this summary of the interview, we were able to obtain a lot of information and a specialist opinion and are very happy about it!

Plant

Plants need 14 essential nutrients to grow and live. Phosphorus is one of the macronutrients that plants need to absorb in larger quantities. Therefore, phosphorus is added to fertilizers. In addition, there are trace elements that are only taken up by plants in small amounts. The following table shows the most important nutrients and their function in the plant:
NUTRIENT ELEMENT- SYMBOL FUNCTIONS
Nitrogen N Green plant pigments, photosynthesis, proteins, DNA
MACRONUTRIENTS,
THEREOF N, P, K AS MAIN NUTRIENT
Phosphor P Enzymes, DNA, flower and fruit formation
Potassium K Water balance, cell walls, metabolism, frost hardiness
Iron Fe Photosynthesis, cellular respiration, enzyme activity
TRACE NUTRIENTS Manganese Mn Pigment and enzyme composition
Zinc Zn Pigment and hormone buildup
Adequate supply of phosphate prevents deficiency symptoms in plants. In the following video, the effects of a phosphate deficiency can be clearly seen using a tomato plant (Solanum lycopersicum). To the right, the same species can be observed, but fertilized with phosphate.

Sediment

In all natural bodies of water in this world, there are little particles that sink down to the ground over time. This process is called sedimentation (lat. sedimentum: deposit) and the particles are called sediments.
Sediment can be classified according to their origin. Biogenic sediments, for example, consist primarily of the remains of dead organisms, as well as the waste products of the metabolic activities of living organisms. Phosphate enters the cycle largely via this biogenic sedimentation, since it is indispensable as a nutrient and basic building block of life for most organisms.
Under the high pressure of the water and the weight of the continuing sedimentation, the loose sediments slowly form a sedimentary rock. Phosphate is also found in this cycle. However, it cannot be economically extracted from it because the degradation conditions under water are difficult, and the phosphate concentrations are low.

Phosphate Mining

Phosphorous is an essential component of life because it is part of the DNA of animals and plants. On Earth, phosphorus does not occur elementally, but only in phosphate compounds. The phosphate minerals that humans consume for industry and agriculture are currently mined in open-pit mines, because a large part of the phosphate is found in the earth's crust. Morocco has a large part of these reserves. This is where the only economic mining currently takes place. In addition, there are deposits under water and in a few other countries, such as China and Algeria. Some experts estimate that the easily accesible continental supplies of the raw material will be depleted by the end of the century. This is problematic because phosphate is an important ingredient in fertilizers. Once the phosphate reserves are depleted, there will be dramatic problems in feeding the growing world population. Furthermore, the quality of the mined phosphate is decreasing enormously. Some deposits are contaminated with cadmium and/or radioactive heavy metals.

Incineration

Current phosphate recovery can be divided into two processes. In thermochemical processes, the sewage sludge from the treatment plant is incinerated and the ash is applied directly to fields as fertilizer. However, this method will be banned throughout the EU from 2029, as the sewage sludge contains enriched pollutants such as drug residues or heavy metals.
In wet chemical processes, phosphate is precipitated with the help of iron and aluminum salts. Precipitation can take place either directly from the sewage sludge or from the ash. In both cases, poorly soluble compounds are formed which must be separated using labor-intensive and cost-intensive methods in order to be able to use the phosphate.
In addition, there are too few plants in Germany in which the sewage sludge can be incinerated. Therefore, the phosphate-containing sewage sludge is often burned together with other non-phosphate-containing materials, such as coal or waste. This reduces the phosphate concentration and makes efficient recovery of this important raw material impossible.
Therefore, there is currently a lack of an efficient phosphate recovery method, which is why we have made it our task to establish a sustainable recycling economy with our project "MEtaPhos".

Genetically Modified Organisms

Genetically modified organisms (GMO) are organisms that have an altered genetic material through genetic engineering methods. The most common of these are modified single-celled organisms, so called microorganisms, such as bacteria, fungi or yeasts. An organism is considered genetically modified if its genetic material has been altered in a way that would not have occurred under natural conditions.
Microorganisms occur in many places in everyday life and are important for life. For example, microorganisms are present in many foods such as bread or dairy products, or in very large numbers in the human body. But they are also important when used for fabric production. This includes in particular the production of pharmaceuticals such as antibiotics or insulin.
When microorganisms are genetically modified, it only means that they acquire new properties or functions, or that a specific function is enhanced so that it can be used in the industrial process. The product and the manufacturing process remain the same.