Wastewater Treatment
Odour & Hydrogen Sulphide
Prevention's and Cures
Hydrogen sulphide (H₂S) is the most common cause for odour in wastewater. H₂S can also result in the corrosion of concrete and steel in sewerage networks.
In Parklink’s experience, the best way to control odour is by improving biology to prevent the production of H₂S. However, sometimes it is not practical or possible to prevent it entirely and therefore H₂S neutralisers are needed to eliminate odour in the air we breathe.
Read on to understand what H₂S is and how it is formed…
What is Hydrogen sulphide?
Hydrogen sulphide is the chemical compound with the formula H2S. It is a colourless gas with the characteristic foul odour of rotten eggs. It is very poisonous, corrosive, and flammable.
How is it formed?
Hydrogen sulphide is produced from the microbial breakdown of organic matter in the absence of oxygen. This process is commonly known as anaerobic digestion which is done by sulphate-reducing microorganisms.
Whats the Solution?
There are a number of solutions available, depending on the situation such as DAZZeL and De-Sulph-A-Nator. Read on to learn about the products or call us today for help on what will work best for you.
Products
Industry leading solutions
for good water quality
Qwik-Zyme L
Qwik-Zyme L
Qwik-Zyme L is an excellent product for grease control in sequencing batch reactors (SBR), wastewater treatment plants, equalization tanks, sewerage networks and food processing plants.
It is the top-of-the-line pump station grease degrader.
This is not a bacterial product, but rather a high tech saliva. This means that Qwik-Zyme L incorporates three types of lipid degrading biocatalysts to provide dramatic hydrolysis of fat, oil, grease (FOG) and resulting fatty acids. Qwik-Zyme L will degrade the FOG, and your bacteria will eat it.
Qwik-Zyme L can degrade a range of fatty acids such as oleic, steric, palmitic as well as fish oils, triglycerides, milk, and animal fats. No more grease, no more foam, and no more backups.
See how it works
The Science Behind It
Why is it so important to control fats, oils and grease?
Qwik-Zyme L was tested against a control for a customer with COD issues. This testing showed a sharp decrease in COD when using Qwik-Zyme L, while the control was essentially at the same level after 4 hours. The control did see an initial increase in COD due to COD chains separating but not degrading and giving the appearance of more COD.
In the winter months, when water temperatures are colder, the naturally occurring bacteria cannot completely break down FOG and the fatty acids that build up in the wastewater plant. These fatty acids are then taken up by filaments like Microthrix Parvicella and Nocardia which allows them to float and foam. Qwik-Zyme L breaks up these fatty acids and cuts off the filament’s food source. It’s fascinating science for wastewater operators.
Qwik-Zyme L – Grease Degrader works well with VitaStim Low F:M and Foam Buster and is used in all types of municipal and industrial applications. For especially tough issues, use the synergistic combination of Qwik-Zyme L and Foam Buster. Foam Buster alters the bacteria populations so the foam will not return while Qwik-Zyme L helps to get the grease under control.
This product is either metered or poured into the front end of the wastewater process. Do not spray this product into the air.
Qwik-Zyme L Applications
- Collection Systems and Lift Stations
- Sequencing Batch Reactors (SBRs)
- Municipal Plants
- Egg Processing Plant
Qwik-Zyme L Benefits
- Reacts quickly
- Degrades fat, oil, and grease (FOG)
- Prevents foaming
- Cleans plants
- Easy to use
Case Studies
Manufacturer of Luxury Soaps Controls Fatty Acid Foaming
Challenge
High Lauric and Stearic Fatty Acids
Solution
Qwik-Zyme L, VitaStim Surfactants
Results
An organic chemical manufacturer in North Carolina contacted us about foam being generated in their treatment system. They use a series of two lagoons, with high aeration in the first lagoon to pretreat their waste stream before sending it to the municipal wastewater treatment plant. The waste stream has high concentrations of lauric and stearic acids which contribute to influent BOD 600 ppm, and COD 200 ppm. The system was not achieving complete breakdown of these fatty acids as the waste stream moved quickly through the system. The operator began using VitaStim Surfactants to add new bacteria cultures which break-down of fatty acids. This improvement was enough to make the customer happy, but we thought that adding our Qwik-Zyme L, liquid biocatalyst product, would help break down the fatty acids even more quickly. The biocatalyst accelerated the process, a huge benefit in this waste stream with a short detention time. The combination of biocatalyst and bacteria brought the systems effluent waste stream down to BOD 8.1 ppm, and COD .4 ppm.
Municipal WWTP and Local Industry
System
Activated Sludge
Flow Rate
120,000 gallons per day
Background
The municipality upgraded their wastewater plant three years ago with fine bubble aeration. Immediately they began noticing a foot of foam on the basins and persistently higher effluent ammonia numbers. They traced the foaming issue down to a tannery in town. The tannery has an existing wastewater process of their own consisting of an equalization tank followed by aeration and a very simple DAF unit. To clean the fat, oil and grease off hides the tannery uses surfactants, substances similar to soap in their make-up. We learned the cause of the issue in the municipal plant was that surfactants were passing through the tannery system undigested, and then foaming when they hit the fine bubble diffusers at the municipal system. The tannery experimented with a number of surfactants to help stop the foaming, but to no avail.
Solution
The solution was to breakdown the surfactants at the tannery’s treatment plant. We had them increase the holding time in their EQ tank to create anoxic conditions and then they added Qwik-Zyme L and Qwik-Zyme P to speed the breakdown the grease and long chain fatty acids. The process was further enhanced by adding Foam Buster to the aeration tank. Foam Buster’s micronutrient blend boosts the ability of native bacteria to degrade fatty acids and grease. The biocatalysts kicked off the surfactant degradation process, and native bacteria with the help of Foam Buster finished the process. Immediately, the city noticed 95% less foam and better settling. As the foam went away they also realized that the surfactants had been knocking out their nitrifiers. As the surfactants were no longer hitting them as they had before, nitrification improved and their effluent ammonia dropped. Now both the municipality and tannery are happy.
Sequencing batch reactor (SBR)
Challenge
A customer in central Alabama has a SBR system that was having an ongoing issue with Microthrix Parvicella. It was causing bad foaming, poor settling, and a cloudy effluent. This plant was out of compliance and needed immediate help. Their flow rate was 100,000 GPD.
Solution
They added 10 lbs. of Foam Buster and 1 quart of Qwik-Zyme L per day for 7 days.
Results
7 days later: Grease was cut in half and settling had improved. 21 days later: The foam was gone and the plant was in compliance with the super tight limits.
Wisconsin Food Processor
System
Trickling Filter>DAF> Aeration Basin
Flow Rate
200,000 gallons per day
Challenge
Malfunctioning DAF-caused foaming in Aeration
Background
To achieve their effluent goals, this processor has to incorporate 2 pretreatment steps before the waste stream gets to their aeration basin. First a trickling filter takes the BOD from around 4000 ppm to 1000 ppm. Next a Dissolved Air Floatation (DAF) unit removes all the grease that the trickling filter didn’t remove. Trickling filters are notorious for allowing grease to pass right through them. They system generally worked pretty well, but was dependent on the DAF making up for the shortcomings of the trickling filter. However, one day a mechanical issue resulted in the DAF being taken offline, and the timeline for getting the replacement part was unknown. With only the trickling filter for pretreatment, and no other way to remove the fats, oils, and grease (FOG) they soon began foaming.
Solution
This customer started with our fatty acids analysis to determine what the concentrations of FOG were, and which fatty acids it consisted of.
Fatty Acid Testing revealed especially high amounts of Palmitic, Stearic, and Oleic acid. Also typically the highest concentration Fatty Acids in municipal influent.
Since the loss of the DAF, total fatty acids in aeration had now jumped up to 7551.5 ppm. The fastest way to reduce the foam was to accelerate the degradation of the very high FOG in the basin. The most prevalent long chain fatty acids are also typically slow to degrade molecules in an aerobic system. The operator used Qwik-Zyme L at a rate of 2 quarts per day, combined with our VitaStim bacteria blend. The biocatalysts in Qwik-Zyme L act on specific structures in the FOG, which allows bacteria in the system to quickly degrade the FOG molecule. Within 30 days the foam had disappeared, despite the DAF unit still not being brought back online.
Downloads
Qwik-Zyme-L Product Sheet AnaerobicDe-Sulph-A-Nator
De-Sulph-A-Nator
Sulfide Odor Control
De-Sulph-A-Nator is a new reactive sulphide odour control agent that functions by encapsulating odorous sulphides and mercaptans, rapidly trapping them in an irreversible reaction.
De-Sulph-A-Nator is a microencapsulant that contains a molecular structure that reacts with the sulphide molecule. This changes the chemistry of the sulphide and breaks it down.
It works fast and is easy to use when compared to traditional oxidants.
Contact us for dose rates for your situation.
The Science Behind It
We have developed this sulfide odor control product to sequester or bind sulfur and mercaptan-type odors.
The De-Sulph-A-Nator forms a permanent bond with the sulfide and it disappears immediately making the air much easier to breathe.
It also stops the sulfide corrosion that costs many wastewater plants thousands of dollars.
This product is widely used in municipal and industrial WWTPs and is extremely popular because it instantly and permanently removes odors.
De-Sulph-A-Nator Applications
- Lift Stations
- Lagoons
- Sludge Storage Tanks
- Digestors
- Wastewater Treatment Plants
- Pit Toilets
- Oily Pits
- Honey Wagons
De-Sulph-A-Nator Benefits
- Encapsulates & permanently removes odors
- Works immediately
- Stops sulfide corrosion
- Easy to use
Dose Rates
| De-Sulph-A-Nator General Dose in pump station/Collection/Sewer line | ||
| Plant Flow Rate Litres per day | Drip Dose | Spray Dose |
| 3,500 litres | 44 - 180 mL | n/a |
| 37,500 litres | 440 - 1,800 mL | n/a |
| 375,000 litres | 3.8 - 17 litres | 1.9 litres |
| 3,750,000 litres | 45 - 170 litres | 7.6 - 15.2 litres |
Dose Rates for Greasetraps
| De-Sulph-A-Nator in Grease Traps | ||
| Size | Initial Dose | Maintenance Dose |
| 350 litres | 355 mL | 90 - 350 mL |
| 3,500 litres | 3.8 litres | 0.95 - 3.8 litres |
| 11,000 litres | 11.4 litres | 0.95 - 3.8 litres |
Downloads
Case Studies
De-Sulph-A-Nator Sulfide Odor Control Case Studies
Municipal Collection System #1
Challenge
Buffalo County is situated along the Mississippi River and the village where Dave works has a collection system that is 8 miles long and ¼ mile wide. This creates long detention times and plenty of time to generate wastewater odours. Testing confirmed the presence of corrosive and odorous hydrogen sulphide gas as wastewater flowed to his wastewater plant.
Solution
They added De-Sulph-A-Nator and OxyPaks XL into their collection system.
Results
De-Sulph-A-Nator and OxyPaks XL knocked out the odours and made the residents happy. When these products are paired they slow the costly effects of corrosion from sulphide gas while eliminating odours.
Municipal Collection System #2
Challenge
A municipal collection system was receiving a lot of grease and odours in their lift station.
Solution
They started using our Bug On A Rope to control the grease and added 8 oz of De-Sulph-A-Nator to control the odours.
Results
The odours disappeared immediately, even on the hot summer days. Before | After
Sludge Storage Tank
Challenge
This municipality is a huge summer tourist destination, and over the years homes have started to surround the wastewater plant. During the hot summer months the odours in their sludge storage tank get really bad.
Solution
To combat this, they used our De-Sulph-A-Nator to bind with the sulphide and prevent odours.
Results
DGTT
DGTT
Drain & Grease Trap Treatment
DGTT is designed specifically to rapidly degrade Fats, Oils and Grease (FOG) in wastewater systems including all forms of grease traps, waste sumps, re-circulation cleaning systems, storage lagoons and biological wastewater treatment plants. DGTT is a highly active microbial-based formulation containing proprietary bacterial cultures that are extremely effective in dealing with systems overloaded with FOG.
Containing only active, non-toxic, naturally-occurring bacteria. DGTT significantly speeds up the microbial response in organic waste that is difficult to degrade. This enhanced microbial response results in a significant reduction in grease sludge, clearer lines and a liquefied slurry that is much easier to pump.
Environmentally friendly, economical and effective
Safe for all pipes, drains, fittings, wastewater systems and receiving environments
Contains added Lipase, Cellulase, Protease and Amylase enzymes
Benefits
- Rapid break down of Fats, Oils and Grease.
- Liquefies FOG solids, assuring quick and easy pumping.
- Provides reductions in final effluent BOD, COD, and TSS.
- Reduces and controls system odour.
What to Expect from DGTT
- Reduction in solids
- Clean pipes and no fat buildup or pipe clogging
- Unclogging outflow water to leach drains
- Fat digestion
- Greatly reduces odours
- Reduces the need for pump-outs and easier to pump
Directions
- Use at 5 to 20/ppm, based on daily flow or system volume.
- For enhanced performance treat undiluted directly into grease trap.
- Add directly to the inlet of the system being treated.
EVERY WASTEWATER SYSTEM IS DIFFERENT
Sometimes greasetraps or septic systems can be grossly undersized for the volume they are expected to process. This could be due to the fact that the original system was designed for a much smaller loading than what it currently receives. Another cause for failure can be too much food waste entering the drains when it should be scraped off into the rubbish bin.
This all makes it difficult to recommend a guaranteed dosing program based simply on the size of your greasetrap or septic tank. Contact Parklink today to discuss your situation with one of the team and ensure you’re dosing the correct amount and the correct product.
ACTI-Mag for wastewater
ACTI-Mag for wastewater
ACTI-Mag is one of the safest, most cost-effective and earth-friendly ways to manage many aspects of wastewater treatment:
Odour and H₂S control
Hydrogen sulphide is present due to anaerobic activity, which favours sulphate reducing bacteria (SRB) and results in the generation of a poisonous rotten egg gas called H2S. Unlike other agents, which can be costly, potentially hazardous, and targeted at a single issue, ACTI-Mag offers a safe and cost-effective strategy for managing odour.
Caustic soda (sodium hydroxide) replacement
While ACTI-Mag is typically more expensive than 50% NaOH on a “price per unit” basis, it is significantly less expensive in use – because every 1.0 kg of 50% NaOH can be replaced by 0.6 kgs of 60% Mg(OH)2 to provide the same number of moles of hydroxide (OH-) for pH neutralization.
Testimonial from Tasman District Council
Tasman District Council has some long wastewater networks that serve coastal holiday settlements with large increases in populations in summer. Due to the long distances and long retention times, odour was a problem where pressure mains discharged into gravity systems during the warm summer months. Calix worked with Council and its Contractor to provide simple, compact, low maintenance dosing systems for three different sites. ACTI-Mag has been dosed into pump stations for at least three months each year since December 2018. It has proven very effective with no odour complaints as a result. It also has had the benefit of reducing corrosion in receiving concrete manholes. The ACTI-Mag dosing systems are connected to Council’s SCADA system, so alarms and remaining products can be easily monitored.
Regards,
Juliet Westbury
Wastewater Engineer
The Science Behind It
- Excessive odour in sewage network, causing odour complaints ?
- Heavy build-up of Fogs layers in the network causing severe corrosion ?
- Excess usage of chemicals like lime and alum, & iron salts leading to high maintenance costs ?
- Frequent need for vacuum truck cleaning leading to an increase in maintenance costs ?
HYDROGEN SULPHIDE (H2S) IN WASTEWATER
Hydrogen sulphide is produced in sewage, due to anaerobic activity which favours sulfate reducing bacteria (SRB) and results in the generation of a poisonous rotten egg gas called H2S. ACTI-Mag effectively locks up H2S to prevent release as a gas that produces odour and facilitates corrosion.
HYDROGEN SULPHIDE (H2S) IS HIGHLY TOXIC…
At just 0.0047 ppm, your customers will start detecting the characteristic ‘rotten egg’ smell of H2S.
NOT ALL MAGNESIUM HYDROXIDE ARE MADE EQUAL.
Unlike many other Magnesium Hydroxide slurries, Calix’s ACTI-Mag is a concentrated (60%) stabilised suspension of magnesium hydroxide.
More solids = Lower required dose.
Case Studies
CASE STUDY SUMMARY
Challenges
- Odour in sewage network due to high hydrogen sulphide (H2S) generation.
- Heavy build-up of Fats, oils and greases (FOGs) in the network.
- Frequent need for vacuum truck cleaning leading to increased maintenance costs.
- High treatment costs due to high chemical use (lime and alum) and associated equipment and maintenance.
Objective
- Manage H2S and odour levels.
- Eliminate or reduce FOGs build-up in the network.
- Save on chemical and maintenance at the treatment plant.
- Ongoing monitoring and optimisation in remote area.
Solution
- Dose the network with Calix’s ACTI-Mag magnesium hydroxide liquid.
- Remote monitoring and weekly reporting, to ensure ongoing control of H2S and pH levels, and optimization of ACTI-Mag usage.
- Eliminate STP lime dosing & reduce alum dosing.
