There are various options available for removing arsenic from groundwater; these processes range from ion exchange and activated alumina to reverse osmosis, coagulation and filtration. Each of these technologies have their own pros and cons, but in cases where arsenic treatment is the main treatment objective, adsorption is the ideal technology from a cost and ease of operation standpoint.
The safe handling of chlorine gas and a secure chlorination system includes a proper facilities design, an operation and maintenance program, the appropriate safety equipment and an emergency action plan. The following, while not all-encompassing, will cover the chemical and physical characteristics of chlorine, as well as the many safety steps and procedures that must be followed to keep your facility safe.
Chlorine is commonly available in three different forms: gaseous chlorine, calcium hypochlorite, and sodium hypochlorite, which are all used in chlorination.
Gas chlorine is typically packaged in 150 lb cylinders and 1-ton containers. This is 100% elemental chlorine stored as a liquified gas under pressure. The chlorine is fed to the process using a pressure feed system which applies the chlorine gas directly to the process or a vacuum operated - solution feed system which uses a water operated ejector to create a chlorine solution which is applied to the process.
Calcium hypochlorite is typically packaged as a solid tablet containing 60% active chlorine. The chlorine is fed to the process using a simple tablet feeder that passes the process water through a tube of tablets, causing the tablets to dissolve into the water. More sophisticated tablet systems dissolve the tablets in water making a solution of controlled chlorine concentration, which is then fed to the process using a chemical dosing pump.
Sodium hypochlorite is a liquid containing 12-15% active chlorine when fresh. Sodium hypochlorite is typically delivered to plant storage tanks by truck and applied to the process using chemical dosing pumps. With this form of chlorine, the concentration decays over time.
In today’s credit-crunched, bottom-line-oriented economic environment, utilities in the water and wastewater sectors are scrapping plans to replace old equipment with new technologies and are looking for ways to improve existing equipment performance with system upgrades.
Injection wells and drilling can be a quite confusing subject for those who are unfamiliar with oilfield operations. This short application spotlight is intended to provide readers with a brief overview of the terminology and processes associated with this subject.
Ozone is commonly used in the treatment of drinking water, but not everyone understands what it is, how it’s used, or the benefits and risks associated with it. We created this blog post to provide a brief introduction to Ozone.
How is Ozone Used for Water Treatment?
Ozone is among the most powerful oxidizing agents known to exist. For this reason, it is often used to compliment chlorine disinfection of drinking water. By using ozone, utilities can limit or avoid the use of chlorine if there’s a concern about dangerous byproduct formation. Once introduced to the treatment process, ozone can safely eliminate a wide range of organic compounds and microorganisms.
Stand-alone ozone effectively treats non-biodegradable contaminants, including micropollutants which are substantially untreated through the conventional activated sludge process. Ozone also treats groundwater that has been polluted by metals, like iron and manganese and inorganics, such as hydrogen sulfide (H2S), that are easily oxidated by O3. Ozone can also be used to remove unwanted colors, smells, and flavors from the water.
What is Ozone?
Ozone is an allotrope of oxygen (different structural modifications of the same element). There
are two main allotropes of oxygen: a diatomic molecule that is made up of two oxygen atoms,
oxygen or dioxygen (O2), and a triatomic molecule made up of three atoms of oxygen, ozone
Triatomic oxygen (ozone, O3), is an inorganic molecule. As a gas it is pale blue in color with a distinctively pungent smell. This very reactive allotrope is destructive to materials like rubber and fabrics and is also damaging to lung tissue. Traces of it can be detected as a sharp, chlorine-like smell, coming from electric motors, laser printers and photocopiers. It is also the strange odor a person would smell after a thunderstorm.
There are many jobs and responsibilities in the field of water treatment. For many, knowing exactly what chemicals or procedures are used in the filtration process is not necessary. However, for those considering on-site water treatment understanding the makeup and uses of chemicals and their components is a vital step in the decision-making process.