Chemistries CLAROS                 800-227-4224

Organic And Nutrient Monitoring For Industrial Process Optimization

Organic-monitoring concerns in papermaking processes can involve the chemical balances required for both process quality and boiler water conditioning.

Organic-monitoring concerns in papermaking processes can involve the chemical balances required for both process quality and boiler water conditioning.

Industrial manufacturers, drinking water facilities, and municipal wastewater managers are concerned about organic contamination ruining their water quality. Knowing the levels of organics and nutrients in source water, process flows, or effluent enables them to optimally manage the treatment and usage of water in their facility. Here are several ideas that detail how choosing the right analyzer technology can help optimize both the performance and costs of industrial water usage.

 


 

A Quick Look Inside Organics Monitoring

Monitoring for organic contamination is the leading way industrial facilities track and manage the quality of their water cycles. Organics are the leading parameter water managers use to treat effluent in wastewater applications, additional industry applications also benefit from real-time analysis of the total organic carbon (TOC) levels in their process water cycles as well as their effluent flows. Industrial processes and byproducts can include difficult to analyze compounds such as fats, oils, greases, sludge, or particulates. Maintaining measurement accuracy over time becomes an added concern for online analyzers with weak oxidation or that require thermal combustion and the inevitable residue that builds up in reaction vessels. Combining a powerful oxidation technology to breakdown complex molecules along with efficient mechanical design, online TOC analyzers from Hach incorporate a patented two-stage advanced oxidation (TSAO) technique to deliver consistent and precise analytical results day in and day out. The robust mechanical design of the Hach BioTector TOC analyzer incorporates oversized tubing and leverages the spent reaction matrix to clean the reaction vessel and effectively wash the reactor and tubing to ensure no carryover between reactions. For continuous monitoring and real-time process control with minimal maintenance — even in processes with heavily soiled samples — the BioTector is chosen time and again by plant by wastewater managers as the primary analytical system that is counted on for detection of organic contamination levels.

 

Because accurate TOC readings are dependent on the removal of all TIC content before sensing for TOC, it is important to use an analyzer that can guarantee complete TIC removal — particularly in applications with elevated TIC values.

Figure 1. Because accurate TOC readings are dependent on the removal of all TIC content before sensing for TOC, it is important to use an analyzer that can guarantee complete TIC removal — particularly in applications with elevated TIC values.

Measuring organics requires careful separation of the C from the compounds in a water matrix. A powerful oxidation method is required to separate C based compounds and must carefully and consistently identify both the TIC and the TOC in a water matrix; TOC equals the difference between the total carbon (TC) and the total inorganic carbon (TIC) in a sample TC = TIC+TOC. Once separated the analyzer then must prepare itself for the next analysis to give a full and credible picture of the health of the water being used or processed in a facility. The method created specifically for industrial applications is the Hach TSAO chemical oxidation. This reliable method starts by lowering the pH of the original sample with acid to sparge off TIC as CO2 gas that is measured and vented. Next, powerful oxidizers and a catalyst are added as a base to the remaining sample to raise its pH and form hydroxyl radicals that oxidize the remaining carbon contamination; TOC. When the pH level of the oxidized sample is lowered again, the resulting CO2 gas is sparged from the sample and measured by a nondispersive infrared (NDIR) light sensor, which is then reported as the TOC level (Figure 1).

 

Real-World Organics Monitoring Experiences

Organics monitoring in industrial applications is critical to the efficient and consistent operation of an industrial facility. From understanding when to do a blow down of condensate in a steam application to identifying lost product that will have to be managed in the facilities’ wastewater treatment plant, without online TOC analysis water managers are blind to the operational cost contributors in their water treatment operation. The value of accurate TOC readings is fundamental to the management of any conventional wastewater treatment process; note that TOC is the main contributor in many BOD and COD loads. In industry, TOC levels give water managers critical information they can use to optimize process operations and pinpoint product losses, cross contamination, or process break-through — issues that can have significant impacts on operating budgets and quality control (QC). Multiple models are available to accommodate a variety of particle sizes and TOC ranges.

In general, online analysis of Total Organic Carbon contamination (TOC) enables industrial users to:

  • analyze raw water influent for pretreatment needs,
  • monitor plant effluent water to maintain regulatory compliance,
  • monitor process flows to ensure optimum product quality and identify potential product loss, cross contamination, or a process break-through.
  • avoid unnecessary waste of treated process water and protect critical process equipment by confirming the quality of condensate recycled back to steam boilers or the quality of cooling tower water being reused.

Facilities that have continuous visibility of changes in organic contamination can quickly identify any changes or cross-contamination and take action before costs or fines accumulate. The benefits of continuous monitoring are covered in greater detail in this companion article about online vs. offline water monitoring.

 

Industry-Specific TOC- And Nutrient-Monitoring Concerns

  • Chemical Processing. Because source water quality can change over time based on water sources and seasonal conditions, being able to quantify TOC levels helps chemical processing plants monitor their incoming organic load and fine-tune their process accordingly. Equally important, monitoring organics throughout the process can be used to identify changes in product quality, spot potential contamination, or identify product loss into the cooling water stream. Monitoring boiler water or cooling water to confirm its quality before recirculating it can protect the investment in already conditioned water against any contamination picked up in the process.
    Discover Hach solutions devoted to the chemical manufacturing industry.
  • Other Industrial Effluent Monitoring. Identifying potential leaks in the process flow is not the only reason for monitoring organics in industrial effluent. Due to regulatory compliance requirements, plants might monitor both the water intake and the plant outfall to ensure that the water leaving the plant contains no more organics than the water entering it. Also, if a plant’s sanitary sewer and process waste streams are combined, it might need to monitor nutrients to ensure that there is an appropriate balance of microbes, nutrients, and organic carbon for reliable biological treatment.
    Learn more about the water cycles and portfolio solutions for industrial manufacturing.
  • Airport Runoff Or Stormwater Monitoring.  Airport drainage represents an exceptional example of highly variable effluent conditions. Broad swaths of impervious surfaces can create huge volumes of stormwater runoff, in a short span of time, at any time of the year. Organics levels can fluctuate from benign levels most of the year, to higher levels caused by dead leaves and grass clippings in the Fall, to extreme concentrations of glycol during winter aircraft deicing events. The U.S. EPA has established specific deicing effluent guidelines to protect the environment. Monitoring runoff for organic content lets airport administrators know whether they can let it drain directly to a river or stream or whether it needs special attention. Rapidly occurring high accumulations of glycol in runoff water can demand immediate onsite treatment or require that runoff be stored in retention s until it can be metered into a normal wastewater flow at concentrations that won’t overwhelm downstream wastewater treatment plants.
    Explore the Hach BioTector B7000 series.
  • Pulp And Paper Manufacturing. Organic-monitoring concerns in papermaking processes can involve the chemical balances required for both process quality and boiler water conditioning, in addition to monitoring wastewater before it is sent for subsequent treatment or discharged to the environment. Organics monitoring might also be combined with nutrient monitoring to maintain the balance of nitrogen, phosphorus, and organics needed for effective biological wastewater treatment.
    Learn more about the pulp and paper industry.
  • Mining and Metals. In mining and metals processing, many contaminants that need to be separated from the process flow — like cyanide or heavy metals — are handled through a settling process. There can be a use for nutrient monitoring, however, when naturally occurring nutrients in the raw materials are present or when metal surface treatments — such as corrosion inhibitors — can introduce nutrients into effluent water.
    Explore additional detail about Hach solutions for the metals and mining industry.