Pharos University جامعه فاروس Faculty of Engineering كلية الهندسة Petrochemical Department قسم البتروكيماويات FERTILIZER INDUSTRY LECTURE (1) 1. INTRODUCTION: A fertilizer is any material, organic or inorganic, natural or synthetic, that furnishes to plants one or more of the chemical elements necessary for normal growth. The plant needs about sixteen essential elements for its growth. These elements are divided to two major types, Macronutrients and Micronutrients.

1.1 Macronutrients: a) Carbon, hydrogen, and Oxygen which are supplied to the plant by air and water, and are therefore, not dealt with as nutrients by the fertilizer industry b) Nitrogen, Phosphorus, and Potassium which are considered primary elements. C) Calcium, Magnesium, and Sulfur which are considered secondary elements.

1.2 Micronutrients: They are required in much smaller amounts and are known as micronutrients or trace elements. They are Boron, Chloride, Copper, Iron, Manganese, Molybdenum, and Zinc. In addition to the 16 essential elements listed above, some other elements have been shown in certain circumstances to be helpful in increasing crop yields or in improving the value of crops for animal or human nutrition. Examples are sodium, silicon and cobalt. The following figure shows the 1 6 essential elements for plant growth.

2.1. Nitrogen (N) Fertilizers: The supply of nitrogen, determines a plant’s growth, vigor, color and yield. Increasing the nitrogen supply to a crop tends to increase the crop’s content of substances that contain nitrogen such as proteins and vitamin B1. The intermediate product in the case of nitrogen fertilizers is ammonia (NH 3 ), which is produced by combining nitrogen extracted from the air with hydrogen which is obtained from natural gas, or through the hydrocarbon steam reforming process 2.Types of Inorganic Fertilizers

The further processing of ammonia produces straight N fertilizers such as urea, ammonium nitrate and calcium ammonium nitrate, as well as solutions of the above fertilizers and ammonium sulphate Phosphate (P) Fertilizers Phosphorus is required for good rooting and resistance to drought, for plant growth and development, for the ripening of seed and fruit and in the manufacture and use of sugars and complex carbohydrates. A good supply of phosphorus is essential in the first stages of a plant’s life and for early maturity.

This nutrient is often described or declared as phosphate (P 2 O 5 ) rather than phosphorus (P). 1 kg P is equivalent to kg P 2 O 5 Rock phosphate ( % P 2 O 5 ) is the raw material source from which most types of phosphate fertilizers are produced, with minor exceptions such as basic slag ( % P 2 O 5 ), which is a by-product of steel production.

To transform the phosphorus into a plant-available form and to obtain a more concentrated product, phosphate rock is processed using sulphuric acid, phosphoric acid and/or nitric acid. Acidulation by means of sulphuric acid produces either phosphoric acid Potash (K) Fertilizers: Potassium controls water relations in plants and helps give plant cells their turgor or stiffness. This is important for crop quality and resistance to disease. Sufficient potassium is also critical for vitamin and mineral content, for texture, firmness and resistance to drought.

This nutrient is often described or declared as potash (K 2 O) rather than potassium (K). 1 kg K is equivalent to kg K 2 O. Most potassium used in fertilizer production is taken from natural deposits of potassium chloride. The mined material is crushed and purified by the removal of rock particles and salt and then applied direct, or more usually incorporated in NPK fertilizers

2.4 Multi Nutrient Fertilizers Multi-nutrient fertilizers produced in the EU are either complex fertilizers (every particle contains the same ratio of nutrients), or blends (made by mixing particles of different materials). Typically, complex NPK fertilizers are manufactured by producing slurries of ammonium phosphates, to which potassium salts are added prior to granulation or prilling. On a global scale, nitrogen is the most needed nutrient (59%) followed by phosphorus (24%) and potassium (17%).