The meter helps accurately monitor flow to ensure accurate enzyme injection
Choosing a flowmeter is not always a straightforward task. Trial and error sometimes proves to be the only effective method of narrowing down what will work in a particular application. There are several choices, including various invasive and non-invasive solutions to flow monitoring. Paddle wheel, turbine and variable area require direct contact with the fluid, while both mag and ultrasonic meters are non-invasive.
Although paddlewheel and variable area flowmeters are more economical, they are not a good choice when the fluid has unknown chemical properties that are abrasive or cause buildup on the unit. A meter without fluid contact proves to be the only solution due to wearing of internal parts, or an impractical maintenance schedule.
URS Div. of URS Corp. provides groundwater remediation services for the Shell Oil Co.’s Carson Terminal in Southern California. The groundwater is contaminated by some unknown bacterial/chemical agent. During the remediation process, the water is pumped through PVC and HDPE pipes, through a series of filters and into a processing chamber where enzymes are injected before being returned to the ground. To be effective, the enzymes must be accurately injected into the water at a rate that is proportional to the water flow rate.
Accurate measurements of the water flow rate and total flow is critical to the application. Initially, paddlewheel type flowmeters had been installed, but a black deposit built up on the paddles which required cleaning every two to three days. The paddlewheel meters were replaced with insertion mag meters which failed after one day, as the coating proved to be non-conductive. A turbine meter was tried and failed after only a few hours of operation. A Doppler-type ultrasonic meter was tested next but it failed to give any measurement at all.
A sample of the subject water was sent to Blue-White’s test lab for analysis. The analysis indicated that there were no particles present that could reflect the sound waves, which made Doppler measurements impossible. However, Transit-Time test measurements were successful using the Sonic-Pro hybrid ultrasonic meter, which can function using either the Doppler or Transit Time measurement methods. The Sonic-Pro was also able to measure and display the sound speed of the fluid which, due to the contaminants, was significantly different from plain water. Knowledge of the actual fluid sound speed is necessary to properly install and calibrate the meter.
In addition, because of the water’s tendency to coat the inside wall of the pipe, which over time also could possibly block the sound waves, the contaminants caused a marked reduction of the sound wave intensity in the groundwater, when compared to clean water. However, the Sonic-Pro’s automatic gain function enabled the meter to function properly over time by increasing and decreasing the sound wave intensity as needed.
Clamp-on Sonic-Pro ultrasonic flowmeters were successfully installed at the site on 2-in. diameter PVC, and 4-in. diameter HDPE pipes, at multiple measurement points. The ultrasonic Transit Time technology proved to be the low maintenance solution to effectively monitor the URS Div. groundwater remediation process for Shell Oil.
Bill McDowell is sales engineer for Blue-White Industries. McDowell can be reached at firstname.lastname@example.org 714.893.8529.
The “CHEM-FEED” Dual Peristaltic Pump Engineered Skid System manufactured by Blue-White Industries. The skid consists of two “Flex-Pro” A3 peristaltic pumps, a calibration cylinder and Plast-O–Matic components, (e.g., eight True Blue manual ball valves, two diaphragm check valves, a gauge with gauge guard, and a relief valve.) Skid Model Number: CFS-2AA-AAAXBA. Pump Model Number: A3V24-MNJ.
LOCATION: Southern Company’s Stanton Energy Center located in Orlando, FL. Stanton Unit A is a natural gas-fueled, combined-cycle electric-generating unit with a capacity to generate 656 megawatts. The combined-cycle plant includes two natural gas-fired combustion turbines, two heat-recovery steam generators and a steam turbine.
APPLICATION: Injecting 12.5% Sodium Hypochlorite (250 – 300 GPD) into the reuse water to prevent biological build-up within the water tubes of the condenser. Any buildup within the condenser would greatly reduce the efficiency to produce steam, hence less mechanical power. In a condensing turbine, the thermal energy of steam is converted into mechanical power, which is converted into electric power by a generator.
PREVIOUS METHOD: Southern Power elected to implement the changeover from Chlorine gas to Sodium Hypochlorite due to cost reducing measures. Maintaining the liquid gas on site required the full- time support of an Emergency Management Team. Eliminating the EMT would reduce operating expenses.
REASON FOR SELECTING THE PERISTALTIC PUMP TECHNOLOGY: The peristaltic pump has proven to be far superior to that of any diaphragm pump when injecting gaseous chemicals against moderate to low pressures. The peristaltic pump maintains a smooth, constant flow rate while eliminating the potential for a vapor lock. The diaphragm pump is adversely effected by off gassing, hence the potential to lose prime. However, the peristaltic pump technology allows any excess gas build-up to be pumped through the tubing while maintaining a highly accurate and continual flow.
REASON FOR SELECTING THE “CHEM-FEED” ENGINEERED SKID SYSTEM: The “Chem-Feed” Skid System is a quality engineered; compact, efficient design, incorporating a high quality, proven “Flex-Pro” peristaltic pump and Plast-O-Matic components that will maintain the integrity of the skid system’s performance. The skid encompasses a full chemical feed design that is less expensive and easy to install as opposed to purchasing the components separately and using an in-house engineering team to design and assemble. In addition, the dual pump “Chem-Feed” model offered an excellent option to an emergency back-up in case down time was required on the primary pump. Lastly, the local chemical feed skid manufacturers proposed out- dated technology of a diaphragm pump based skid system as well as using components that were far less inferior to the Plast–O-Matic components used with the “Chem–Feed” System.
RESULTS: Southern Power is extremely pleased with the “Chem–Feed” performance since it has been installed in September 2010. The ease of installation of a UPS delivered chemical feed skid system was a remarkable feature, far exceeding their expectations. The “Chem–Feed” Skid System comprised of the A3 peristaltic pumps should expect to see a minimum of 7000 – 7500 hours of tube life based on previous applications with similar chemicals and pressure ranges of less the 20 PSI.
Sonic-Pro® S3 Flowmeter Helps Maintain ‘Food to Microorganisim’ Balance in Return Activated Sludge Line
Keene Waste Water Treatment Plant
Keene Waste Water Treatment Plant uses a secondary treatment process called activated sludge, a process which converts non-settable substances into a biological floc. This substance is developed in aeration tanks and settled out in final settling tanks. Activated Sludge is an aerobic process which promotes the health of microorganisms, ensuring effective treatment. A food and oxygen to microorganism balance must be maintained for optimal treatment. One element of maintaining the biomass requires returning of a portion of the settled sludge from the final settling tanks back to the aeration tanks, keeping the bio system balanced. This portion of the activated sludge is referred to as RAS (Return Activated Sludge). The RAS is returned to the aeration tanks via variable speed centrifugal pumps where accurate flow rate measurement is critical to ensuring a proper ‘food to microorganism’ ratio is maintained. The RAS flow rate is determined by laboratory analysis of the microorganism’s health, the flow rates are adjusted accordingly.
Keene Waste Water Treatment Plant required flow measurement in a Return Activated Sludge line. Previously, a Magnetic Flowmeter had been selected for the job, however they were getting a high variance in read out measurements. It was determined that there were stray electrical interference currents causing the inaccurate readings. Due to its failure in accuracy, Keene Waste Water Treatment Plant sought an alternative that would handle the job. Because Ultrasonic Flowmeters only measure sound waves, the electrical interference would not hinder its performance.
Installation & Solution:
The treatment facility required reliable flow measurement with 4 to 20mA output on an existing 18” ductile iron RAS line. The Blue-White® Sonic-Pro® S3 Ultrasonic Flowmeter proved to have all the capacities necessary for the task. Utilizing the dual Z-Mount T-Track mounting system, installation of the flow meter was completed within 60 minutes. With an easy to follow instruction guide, the electronics were configured quickly to accurately measure the flow of the RAS pipe. The Blue-White® Sonic-Pro reliable flow measurement was able to solve the facilities system requirement, without any intrusive equipment, or altering of the existing pipeline.
Blue-White Ind. Case Study – Poultry Farm Egg Production
Sonic-Pro S3 Ultrasonic Flowmeter Remotely Monitors Water Wells
Rainbow Farms Company is in the poultry business (layers – eggs). Rainbow Farms has twenty five
poultry houses with a total of 1.7 million layers, a processing plant, and a distribution plant located on
640 acres (one square mile) in Denair, California. Water is a very important factor in the business. It is
used for refrigeration, egg washing, drinking water for the layers and for evaporating cooling and
foggers in the poultry houses.
Monitoring water flow into the complex in the summer months, as well as in the winter, is very important. Should a problem occur at one of the well sites, it must be diagnosed and resolved as quickly as possible. To ensure an adequate supply of water, Rainbow Farms determined that remote monitoring was required to monitor the critical water output from four different well sites which are spaced approximately ¼ mile apart on the 640 acre complex.
Sonic-Pro ultrasonic clamp-on flowmeters were installed on each of the four wells. The Sonic-Pro’s ability to clamp onto various pipe sizes and materials plus its Ethernet connection, provided the means to send real-time flow data over a wireless network directly into the control room. David Bryson, Production Supervisor st Rainbow Farms notes that “Each of the twenty five poultry houses have low pressure alarms, so having the ability to remotely view the actual flow rates being produced from all of the four wells helps me determine very quickly which well is not working correctly or offline.” The Sonic-Pro clamp-on hybrid ultrasonic flowmeter. The ability to remotely monitor multiple pipe applications via Ethernet, measure various fluids, and pre-save multiple configurations for fast and easy installations made the Sonic-Pro a clear choice.
Case Study for Blue-White Injector at Pierce Farm Center
Pierce Farm Center
Los Angeles Pierce College
Woodland Hills, CA
We are a 22-acre demonstration farm that functions on an agri-tainment/ educational basis, in the western end of the San Fernando Valley. 2009 was our fifth year of business, but the first time that the farming was done in-house. As such, we were trying to develop modern and sustainable farming practices for their economic, environmental and educational benefits.
All of our crops are grown for fresh market production and sold through our farm market. These crops include bush and cluster tomatoes, sweet corn, summer squash, cucumbers, eggplant, bell and chili peppers, basil and several varieties of pumpkins grown for our Harvest Fest. We also grow a corn maze planted with field corn.
As part of our modern farming practices we almost exclusively used sub-surface drip irrigation to supply water and wanted to take advantage of that by using liquid fertilizer injected through our drip tape.
The nitrate portion of a fertilizer is highly susceptible to leaching. This means that excessive levels of nitrogen need to be placed pre-plant if it is to last throughout the season and be available for the plants as they need it, leading to large quantities of nitrate leaching into the groundwater and lost dollars.
By using liquid fertilizer in sub-surface drip we were able to minimize our pre-plant dry fertilizer application, and give small doses of nitrogen throughout the season, placing it right around the root zone where it can be of most benefit to the plant.
Aside from actual application, our largest problem was that we have multiple crops growing at one time that are dispersed amongst several fields, thus we needed an injection unit that was small, easily moved, yet still maintained a certain level of accuracy.
We found that the Blue-White diaphragm metering pump fit the bill. It is light and easily transportable. The injection fittings were both easy to attach to our riser set-ups and easy to connect to. After figuring out the desired quantity of fertilizer to be applied, it was as easy as pressing a button and knowing that so many gallons per hour were being applied to our fields.
Our crops this year were fantastic, our yields were improved, we used 25% less granulated fertilizer and 25% less liquid fertilizer as compared to the previous farmer who used a venturi type pump.