Solutions

Disinfection Alternatives

We have been known for our knowledge and huge success in Capital Controls / Severn Trent gas chlorination systems. These systems are generally low in operating cost.

Many customers choose to feed 12% bleach solution with ProMinent metering and control systems for lower capital costs and easier handling than with Cl₂ gas. Operating cost is higher for shipping the lower concentration product as compared with pure Cl₂ gas.

In recent years, there has been an increasing interest in generation 0.8% sodium hypochlorite solution on site using ClorTec / Severn Trent systems, due to the non-hazardous safety considerations, simplicity of operation and readiness of raw materials (salt, water and power). Such systems are the most capital intensive; however, the cost of production of 0.8% solution is generally much lower than the purchase price of both Cl₂ gas and 12% bleach. Over time, the savings in chemical cost will offset the initial investments. The payback period is dependent on the cost difference between local production and chemical purchase. ClorTec systems are also used in swimming pools. The City of Calgary contracted ClorTec to supply a system consisting of 3 x 1500 ppd generators and control. Epcor entrusted ClorTec to supply a 5 x 1500 ppd system at the E.L. Smith WTP.

UV is found to be effective in inactivating reproduction of giardia and crystosporidium oocysts. We are well positioned with medium pressure UV systems from ProMinent, and low pressure systems by UltraDynamics / Severn Trent.

Cl₂ Monitoring & Top-Up

It is a common practice to control chlorine feed rate (flow paced, residual and compound loop) in water plants. water plant clear-wells and storage reservoirs are generally sized to accommodate peak demand for fire fighting. After many days (and sometimes weeks) of storage, residual chlorine levels may have dropped. It is important to know the effluent chlorine level, and if warranted, to be able to top up to the required chlorine residual value. We have supplied many such systems.

See the ProMinent brochure that illustrates chlorine sampling, analysis and top-up control for a typical pump station. Water samples taken downstream of chlorine injection are continuously analyzed and a control signal is sent to the bleach metering pump to modeation the feed rate so as to maintain the effluent chlorine at the required value. For gas chlorine systems, the metering pump is substituted by a chlorine control valve.

Aztec / Severn Trent supplies several chlorine analyzers (Model 1770 for free chlorine, Aztec CL500 and CL1000 and MicroChem2 for free and total chlorine). The MicroChem2 analyzers can be furnished for pH/ORP measurement, with control functions to moderate chlorine feed.

Chemical Feed Systems

The German made ProMinent products lead the world in innovative design and high quality reliability. The solenoid GALa pumps (1.1 l/h at 253 psi up to 32 l/h at 29 psi) and Sigma 1/2/3 motor driven pumps (20 l/h at 145 psi up to 1000 l/h at 58 psi) share the common built-in display/control box (external VFD is not required). These pumps can be purchased in manual or control mode. The display/control box features include: digital display of stroke position in %, stroking frequency in spm, 4-20 mA input value, instantaneous feed rate in l/h or gph, totalizer for strokes and metered volume, and optional 4-20 mA output representing the feed rate. each pump can be calibrated in feed rate and back pressure for added accuracy.

The pumps can be supplied loose or packaged with accessories such as self-fill calibration column, pressure relief valve, back pressure valve, pressure gauge, strainer and flow monitor (to verify flow output), and pre-installed/tested on PE or SS skids. This package pump/accessories/skid design has been very well received by design engineers and customers.

We also supply Ultromat continuous polymer solution blenders by ProMinent, batch blenders by Fluid Dynamics. Merrick supplies dry chemical feeders, solution preparation systems, lime slakers and bulk bag feed systems.

Chemtrac SCM is used to monitor/control coagulant feed for water treatment and sludge dewatering.

Since 1908, Merrick has specialized in dry chemical handling and feed systems. Products include: volumetric feeders, gravimetric feeders, bulk bag handling and feed systems, and lime slakers.

Nutrients Monitoring

Since 1996, we have supplied over 17 ChemScan process analyzers to monitor nutrients for many WWTP in Western Canada. The analyzers are typically used to measure orthophosphate, ammonia, nitrate and TSS in secondary effluent. They can also be configured to measure/estimate nitrite, BOD, COD, NOM, UVT, etc.

ChemScan analyzers send a 256 wavelength UV light through a water sample and apply a mathematical algorithm to analyze the absorption spectrum. Multiple streams with multiple parameters can be handled with one analyzer.

ChemScan analyzers have been used in many Florida WWTPs to analyze ammonia, nitrate and nitrite in aeration tanks for blower control and nitrification/denitrification optimization. Design is currently taking place for a BNR monitoring system to sample 8 locations in the anaerobic/anoxic/aerobic zones in the Pine Creek WWTP, Calgary.

Water Quality Monitoring

At the current state of technology, oocysts of giardia and crytosporidium cannot be detected instantly. Particles generally between 2-10 microns are used as surrogate to indicate probable presence of the parasites. Chemtrac PC2400D particle counters with user-friendly TracWare interface software are used extensively. These also support multiple communications protocols: Modbus, Profibus, Optomux, OPC/DDE server and Web server interfaces.

ProMinent supplies on-line analyzers for chlorine, fluoride and pH/ORP/temperature.

The Aztec / Severn Trent line includes Ion Selective Electrode (ISE) and Colorimetric based systems. ISE systems measure ammonia, fluoride and nitrate. Colorimetric systems are used to aluminum, ammonia, color, manganese, nitrite, phosphate and silica.

Chemtrac particle counters and monitors are used to monitor membrane fouling due to particles.

Aysix supplies the optical D.O. measurement systems. It does not require electrolyte solutions or membrane change. No more constant calibration or probe fouling. Just wipe the sensor with a soft rag or soft toothbrush. Aysix systems can be supplied with single/dual sensors: DO/DO, DO/TSS and TSS/TSS.

ChemScan monitors and controls chloramination processes.

NEXTChem manufactures analyzers for many parameters for process industries

WWTP Headworks

Headworks Inc. specializes in coarse and fine screens, in-channel screens, screening conveyors/compactors and septage receiving stations. The acclaimed Mahr Bar screens are known for: combined fine and coarse screen; patented auto-reverse mechanism; reducing blinding (with cleaning cycle down to two seconds); high hydraulic profile and low headloss (even with 6mm openings); low profile.

Hi-Tech Environmental's headwork equipment include in-channel screens, detritus tank grit collectors, grit clarifiers and grease &s; grit removal systems.

Clarifiers / Fermenters

Hi-Tech Environmental manufactures painted carbon steel and 304/316SS primary and secondary clarifiers with different designs: pier supported, Ultra-Sweep spiral blade, rapid sludge removal by organ pipe and tapered sludge collection header, and conventional scraper. We also supply circular DAF for sludge thickening, rotary distributors for trickling filters, aerated grease and grit removal systems, package WWTP and replacement cast iron and fabricated steel clarifier drives. New product: In-Channel Screens.

For water treatment, use Clear-Flow Solids Clarifiers and Flocculation Clarifiers.

Enhanced Anaerobic Digestion
Foaming Abatement

Sonico uses patented ultrasound devices to break down cell walls of thickened waste activated sludge. Benefits include:

• Breakdown of filamentous bacteria, which cause foaming
• Increased biogas production
• Reduced solids production
• Increased sludge loading rate (due to increased reaction times)
• Enhanced sludge destruction rates
• Improved digester operation and stability
• Increased dewaterability of final sludge cake

Digester / Equalization Tank Mixing

Inefficient anaerobic digestion is generally caused by inefficient mixing. JetMix uses eccentric nozzles (fixed or 360^o rotatable) and pumps to create a thorough unique patented toroidal mixing pattern (in circular tanks). Benefits include:

• Suspension of solids with intermittent mixing, power savings of up to 90%
• Maintain mixing efficiency regardless of liquid level
• Reduced capital and operating expenses
• Requires no scheduled maintenance inside the tank
• Eliminates nozzle maintenance; JetMix has not clogged a single nozzle in over 11 years

Olympus Technologies specializes in anaerobic digestor covers, gas holder covers, mechanical mixers and digester accessories.

Rapid Response Water Test System (RRWTS)

The Ecolox / Severn Trent RRWTS is a portable luminometer used to carry out a series of first line water testing. It is a generic qualitative test providing a broad indication of water quality. it is not a comprehensive analysis. This system enables the user to rapidly detect variance in water quality and can signal the need to additional quantitative laboratory testing.

Ecolox uses the chemiluminescence process, a chemical reaction that occurs in a water sample when specific reagents are added. A byproduct is light that is measured by the luminometer. When a toxic material or a contaminant is in the water, it will generally inhibit the light production. By establishing a baseline reading on a contaminant-free sample, subsequent samples can be measured and compared. Any deviation is indicated on the luminometer.

In Situ Odor Control without Chemicals

This is a patented, but simple process. The Vapex System uses power and water to form a very reactive hydroxyl ion fog. The ions oxidize H₂S into elemental sulphur.

Inject the fog into enclosed tankages such as wet wells, pump stations and remove H₂S in situ.

Small foot-print - no chemicals - no by-products - low operating cost.

Operation Enhancements

Filter Backwash Use Aysix Expansion Pro EPA2000 for media expansion measurement to take guesswork out of gravity filter backwashing. Primary benefits: improved filter cleaning; extended filter run time; reduce media loss; promote even media re-stratification.

TSS Measurement Aysix supplies monitors for MLSS and TSS in RAS/WAS channel/line, for SRT management.

Sludge Interface Aysix BinMinders are successfully operating in: primary and secondary clarifiers; gravity thickeners; reactor clarifiers; DAF thickeners.

VFA Measurement Applitek supplies on-line analyzers for: VFA, bicarbonates and partial/total alkalinity. Other analyzers for: sludge volume index; TN; TP; BOD and toxicity.