DELOACH BLOG

Caustic solution for Sodium hydroxide water treatment of Sodium Hydroxide

There are many industries that require the use of a caustic scrubber which is considered a chemical scrubber and they range from the municipal industry, mining, semiconductor markets, pulp and paper, and chemical refining.  There is a wide variety of industrial processes that generate noxious or corrosive off gases that require treatment and a comparison is made between biological Vs. chemical.  Often biological scrubbers have limitations due to concentrations, composition, or temperature of the contaminants and if the gas stream contains acid fumes then a biological scrubber is quickly ruled out.

The odor control selection is often fraught with choices of capital cost over operational cost and quite often comes down to familiarity from the designer or purchaser.  It is always a good idea to freshen up the industrial odor control the do’s and don’t’s before selecting the final solution.  If the off-gas source that needs to be treated is hydrogen sulfide (H2S) or some other type of gas stream produced by an acid or ammonia it will often require neutralization for human health reasons and to protect equipment or may be required to meet regulatory compliance. Caustic scrubbers may be either vertical or horizontal by design, but both utilize a packed media bed of either random packing or trays to allow the gas fumes to meet the recirculating caustic solution which then forces the reaction to occur.

Topics: water treatment issues, water quality, degasification, pH levels of water, odor control, water treatment, advanced treatment solutions, biological scrubber, water plant, odor control scrubber, hydrogen sulfide (H2S), Chemical Odor, pH levels, caustic, wastewater, carbon dioxide, degasifier, gases, caustic solution, sodium hydroxide water treatment

What type of Odor Control Scrubber do I select?

Topics: water treatment issues, water quality, degasification, pH levels of water, odor control, water treatment, advanced treatment solutions, biological scrubber, water plant, odor control scrubber, hydrogen sulfide (H2S), pH levels, degasifier, gases

A Biological Scrubber is a wet odor control scrubber that treats and removes contaminants from an air stream.

It utilizes caustic typically to control the pH of the re-circulation solution. There are several types of odor control and chemical fume scrubbers on the market today. Each plays a role in treating noxious or corrosive gases in the industry.

Biological scrubbers are used in municipal applications to treat low and high hydrogen sulfide (H2S) gas levels. This colorless gas is removed from the water or wastewater treatment process. 

Water treatment equipment such as “degasification” or “decarbonation” towers.

Strips the hydrogen sulfide gas from the treated wastewater and exhausts the gas from an exhaust port. These gases are captured and sent to the biological scrubber via an air duct system. The health effects of hydrogen sulfide can cause eye irritation, loss of appetite, and fluid in the lungs. Hydrogen gases are captured at a wastewater treatment process, including treatment facilities, lift stations, or head-works facilities. The PVC or FRP duct system sends the gases to the biological scrubber.

How does a Biological Scrubber work?

A biological scrubber utilizes tiny microorganisms (bacteria) to break down and digest contaminants. The bacteria feed on the contaminants and utilize this as a feed source to live and grow. When utilizing a biological scrubber for hydrogen sulfide (H2S) treatment, the by-product waste is acid from the digested H2S. This lowers the pH and requires the use of caustic to buffer the water and nutrient solution that is recirculated within the scrubber to maintain a neutral pH. The captured gas containing contaminants enters the bottom of a vertical biological scrubber. Similar to how the gas enters any other type of chemical scrubber or single or dual pass odor control scrubber.

The gas stream travels upward. Passes over a media bed that has been cultured to grow live microorganisms. A biological odor control scrubber already has “artificial intelligence” because of the millions of microbes colonies it supports.  

Topics: water treatment issues, odor control, advanced treatment solutions, biological scrubber, odor control scrubber, hydrogen sulfide (H2S), Chemical Odor, dissolved gases, wastewater, carbon dioxide, degasifier, gases, RO system, H2S Degasifier, what is a scrubber

Odor control and acid scrubbers are both popular in many industries.

Topics: odor control, water treatment, biological scrubber, odor control scrubber, hydrogen sulfide (H2S), Chemical Odor, dissolved gases, carbon dioxide, degasifier, gases, H2S Degasifier

The type of Odor Control Wet Scrubber selected for the treatment and neutralization of Ammonia (NH3) gases depends on several variables, including the type and source of the ammonia gas and whether or not it is “Free” ammonia and or unionized.

Ammonia is a very miscible and stable molecule with solid hydrogen bonds, making it very soluble in water and difficult to treat without using a properly designed and sized ammonia scrubber. The concentrations, air flow rates, temperature of the gas stream, and chemical reagents being utilized, such as caustic to remove and then treat the ammonia, all play a significant role in the removal efficiency of the ammonia gas scrubber system. Unlike other types of “odor control scrubbers,” an ammonia scrubber is much more sensitive to variables such as the gas stream temperature because of the solubility of ammonia.

Ammonia is produced from nitrogen and hydrogen 

the process is called the Haber Process by combining nitrogen with air and adding pressure, you can make ammonia.

It takes about 200 atmospheres of pressure, and the process varies from refinery to refinery. Still, on average, you can only make approximately 15% of ammonia during each pass which takes multiple passes to achieve the 15%. The reaction to make ammonia is exothermic when produced in a refining process. 

However, ammonia is also formed in nature in smaller quantities. Most ammonia (90%) is utilized for fertilizer production, but ammonia can be found in food, pharmaceutical products, and cleaning supplies. When ammonia gas is released into the air, it has a very noxious and pungent odor that can be dangerous to inhale, so often, odor control scrubbers are required to capture and treat the ammonia gas.

Topics: water treatment issues, water quality, degasification, pH levels of water, odor control, water treatment, advanced treatment solutions, biological scrubber, water plant, odor control scrubber, hydrogen sulfide (H2S), Chemical Odor, pH levels, Decarbonation, dissolved gases, wastewater, degasifier, gases, H2S Degasifier, Ammonia

In the United States manufacturing industry, an astonishing 400 million gallons of water per day (MGD) is consumed to generate steam.

Out of this amount, approximately 60 MGD is sent to blow-down drains, while another 300 MGD is used for direct injection of steam. The common denominator in all of these processes is the need for purified and treated water. Without proper treatment, manufacturers would face frequent shutdowns and increased capital expenditure, significantly impacting their cost of goods. One effective method of water treatment to protect boilers is through degasification and deaeration.

Degasification towers play a crucial role in removing harmful gases such as hydrogen sulfide (H2S), carbon dioxide (CO2), and often dissolved oxygen (DO). The elimination of these corrosive gases is vital for enhancing the lifespan and efficiency of boiler systems. If these gases are allowed to remain in the boiler feed water, particularly carbon dioxide (CO2), it can lead to disastrous consequences, including higher operating costs and reduced system longevity. Carbon dioxide (CO2) can convert into carbonic acid, creating a corrosive environment for the boiler and other critical components. In cases where an ion exchange process is implemented prior to the boiler, the presence of carbon dioxide (CO2) can drastically increase regeneration costs as the resins are consumed. By removing carbon dioxide (CO2), the life of the resin is extended, and the pH of the water is elevated, reducing the need for additional chemicals and further lowering operating costs.

Topics: water treatment issues, degasification, iron oxidation, water treatment, water distribution system, advanced treatment solutions, water plant, hydrogen sulfide (H2S), Decarbonation, ION Exchange Resin, feed water, De-Aeration, steam generation, steam generating boilers, carbon dioxide, steam, decarbonator, boiler system, degasifier, gases, RO membrane, carbonic acid, RO system, H2S Degasifier, Boiler feed water

Avoid problems with calcium chlorite and corrosive gasses with your odor control scrubber.

When planning or designing an odor control system, one should pay close attention to several key variables that can cause havoc on a chemical odor control scrubber when trying to treat hydrogen sulfide or ammonia gases. The need for odor control occurs in many different forms. It is essential to understand the process that is creating the odorous or corrosive gas and the need for odor control & air emissions treatment.

First, begin to identify

all the potential obstacles that may creep up later after the chemical odor or corrosive gas control system goes online, like acid or caustic consumption. For example, chemical odor control systems designed for water treatment for the municipal industry are typically needed and attached to a degasification or decarbonation process, often needed to treat hydrogen sulfide (H2S). However, designers often may not pay close enough attention to the type of water process available for “make-up” water for the chemical scrubber. The addition of caustic can create scaling or fouling. This unknown variable of the makeup water quality can lead to a complete tower shutdown if the chemical scrubber distribution and media bed scales or fouls. The most commonly used chemicals for a hydrogen sulfide (H2S) scrubber are either chlorine in the form of sodium hypochlorite or caustic in the form of caustic soda. Both of these chemicals are common to a water treatment facility and are already in place to adjust and control pH.

The makeup water plays a significant role in the operation of a chemical scrubber.

When water containing high hardness levels is used as the source for the makeup water, your chemical scrubber can become fouled, and scaling can occur in a matter of hours, depending on the alkalinity and salts within the water. Solidification can occur from the scaling when combining sodium hypochlorite and raw feed water at specific pH ranges and these ranges are usually the range needed to achieve peak performance. Calcium chloride will form, and your chemical odor control scrubber will become a solid chunk of calcium chlorite making, making the ability for water or air to pass freely through the media packing next to impossible. No matter what type of media packing is utilized in the odor control or gas scrubber, it can foul and scale if the water chemistry is incorrect.  Trust me when I say “been there and done that”!  I have seen operators who have allowed a chemical scrubber to become out of balance with pH control and completely solidify the tower column to the degree that neither air nor water passage is possible. The problem can still occur with ammonia scrubbers but are different with different sets of parameters.

Topics: odor control, water treatment, advanced treatment solutions, biological scrubber, water plant, odor control scrubber, hydrogen sulfide (H2S), calcium carbonate, media packing, pH levels, Alkalinity, Langilier index (LSI), scaling, chlorine, caustic, ION Exchange Resin, Safe drinking water, dissolved gases, De-Aeration, carbon dioxide, oxygen, degasifier, gases, H2S Degasifier, calcium chlorite

The water treatment industry has developed and evolved over the years to continue to find new ways to produce degassed water,

Topics: water quality, degasification, pH levels of water, water treatment, advanced treatment solutions, water plant, safety, hydrogen sulfide (H2S), Chemical Odor, media packing, pH levels, Decarbonation, dissolved gases, wastewater, Global, carbon dioxide, decarbonator, degasifier, gases, RO membrane, H2S Degasifier, degassed water

Ten years ago if I had purposed that one day our water would have artificial intelligence I think I would have been laughed out of the industry. But now, anything you can imagine with the new electronic revolution is possible because of the current revolution referred to as “The Internet of Things” (IoT). Placing nano-size SIP (Systems in a package) into a water stream and tracking its path or location or performing inspections on critical infrastructure or equipment is now a reality.

Topics: degasification, water treatment, advanced treatment solutions, water plant, phosphate levels, pH levels, Alkalinity, Global, decarbonator, degasifier

When do you know if your decarbonation system needs service?

When a degasification tower or decarbonator becomes fouled, several indicators identify you may have a problem or that it's time to clean your system. If the efficiency of the degasifier has dropped, you will see an increased consumption rate of chemicals. If you remove less hydrogen sulfide gas from the degasifier, chlorine consumption will increase. When you increase the amount of chemical reaction occurring in the water, you will see an increase in the TSS levels and a drop in water quality. As the H2S reacts with chlorine, more solids will form and be present in the water, and the water quality will diminish.

Another indicator of a fouling condition is the pH adjustment in the Industrial Water Treatment industry. You are required to meet the set standards. As the performance of the tower drops, the removal of CO2 will also drop, leaving a higher pH level than may be desired. A quick inspection to check out the media bed should be performed. Also, do not forget to inspect the distribution system at the top of your tower and remember that all distribution systems are not alike, and inspecting the condition of each of them may require additional effort on your part. With a header lateral system, you need to inspect the distribution nozzles, but with a Weir or Tray type, you will need to check the amount of scale or fouling building up on the Weir edge or in the bottom of the pan. If the Weir edge becomes fouled unevenly, it will create "Channeling" of the water and increase the initial hydraulic load to a concentrated point on the media bed.

Topics: water treatment issues, blower maintenance, aeration, water treatment, advanced treatment solutions, degasifier, Deagasification, decarbonation of water