How do I Convey Dry Hydrated Lime?
What Is Dry Hydrated Lime Used For?
Dry hydrated lime is a powdered, inorganic compound that is widely used as a sorbent to mitigate harmful gases and compounds from electrical generation and industrial process exhaust. The material is especially effective in mitigating SO2 (sulfur dioxide) and SO3 (sulfur trioxide) emissions caused by burning coal as fuel. When combined with moisture in flue gases, either of these byproducts will produce vapor-phase sulfuric acid. Sulfuric acid is extremely hazardous to humans and can corrode ducts and damage downstream equipment.
Dry hydrated lime is also commonly used in construction materials. It is a key ingredient in the synthetic gypsum used to create gypsum wallboard. Hydrated lime is also used to produce Portland cement for masonry purposes.
The compound is used extensively as a flocculant in water and sewage treatment, as it forms a “fluffy” solid that collects and helps remove smaller solid particles from water. Under its scientific name, calcium hydroxide, dry hydrated lime is used in an array of food processing applications. Calcium hydroxide is used to clarify/filter liquids, as a binder for other ingredients, and as a digestive aid.
Material Characteristics of Dry Hydrated Lime
Dry hydrated lime is a powdered, inorganic compound manufactured by slaking quicklime, or calcium oxide (CaO), with just the right amount water to satisfy its natural chemical affinity for water while still retaining its powdered form. The addition of water converts the oxides into hydroxides, forming calcium hydroxide (Ca(OH)2). There are several different types of dry hydrated lime, but all are essentially the same, chemically. Hydrated lime can also be produced as a semi-liquid slurry.
Dry hydrated lime exhibits relatively high water solubility, and produces an alkaline solution with a pH of ≈12.4 when dissolved in water at room temperature. Dissolved hydrated lime solutions can be highly corrosive to metals such as aluminum, while passivating the surface of other metals, like iron and steel, thereby improving their corrosion resistance.
Due to its granular, powdery form, dry hydrated lime generates large amounts of airborne dust. This dust can be hazardous to personnel, as unprotected exposure to dry hydrated lime can cause severe skin irritation, chemical burns, lung damage, and blindness.
Recommended Conveying Solution
The best and most effective way to convey dry hydrated lime is by pneumatic conveying. Nol-Tec designs and installs dilute phase pneumatic conveying systems that use low pressure, high volume air at controlled pressures to safely move materials like dry hydrated lime down the convey line. Proprietary Air Assist technology maintains equal motive energy from the beginning of the conveyor to the end, regardless of the layout or length of the system.
Our fully-enclosed pneumatic conveyor solutions minimize airborne dust and eliminate material loss. We will work with you to develop a system that is configured to fit your space and tailored to your application and performance requirements.
Contact Nol-Tec to get started on a custom dry hydrated lime conveyor system for your application.