Online Total Organic Carbon Measurement In Process Plants

Process plants need to be exceptionally aware of environmental issues and norms due to the nature of the products that these companies deal with. Quite often the chemicals and liquids used in these processes are toxic and even a small spill into a river or a natural water source can spell disaster. These companies produce a toxic effluent that is completely different from that of a municipal plant. Hence, they often have their own treatment plants.

Quite often the chemicals and liquids used in these processes are toxic and even a small spill into a river or a natural water source can spell disaster. These companies produce a toxic effluent that is completely different from that of a municipal plant. Hence, they often have their own treatment plants.

Total Organic Carbon

Total organic carbon (TOC) content is an important element that needs to be measured and monitored so that bio mass can sustain. The use of TOC analysers, together with flow meters, in different production areas helps in minimising product or process loss. Each of the production areas also becomes independently accountable for the amount of effluent discharged.

TOC monitoring at the inlet of the treatment plant is essential to ensure excessive levels of chemical are prevented from entering the plant. Quite often this highly contaminated effluent is diverted to a holding tank and disposed off by specialist companies. If the final effluent from the treatment plant is being discharged to a river or sea, then TOC monitoring is generally used to ensure compliance.

Monitoring TOC in the Food Industry

The food industry as a whole uses large quantities of water during the manufacturing process. The very nature of these products means that it will be very high in organic carbon.

The milk industry suffers from very high product losses. Monitoring product loss with the help of turbidity meters has been tried for years, but without much success. Many plants have now shifted to TOC analysers to monitor different areas of production. They have been successful in reducing product loss by detecting when mechanical failures occur and bad housekeeping is taking place.

The beer industry is very similar to that of the milk; they have tremendously high peak loads in their effluent discharge. It has been proven that by using a TOC analyser and monitoring the effluent in real time it is possible to find the causes of the high organic discharge and significantly reduce them.

The softdrink industry uses large amounts of sugar in the production process. Like in other industries, a lot of product is likely to be discharged into the effluent. It is important therefore that this industry monitors the organic level to prevent high discharges to the effluent treatment plant. This would result in financial benefits, both in terms of reduced product loss and treatment charges.

Product Loss Monitoring

The integration of continuous water quality monitoring in production areas can be used to identify product loss in real time. Instrumentation to monitor drains within bottling plants, after fermenters and post CIP has been used to identify when product loss has occurred. Events can be alarmed in real time by instruments such as the FMTOC101 Total organic Carbon analyser, so corrective action can be immediately taken.

Distillers claim that the unique taste of their whisky is due to the water that it is made from. This water is quite often obtained from bore holes, rivers, etc. and it would therefore be logical to monitor the quality of this water firstly to ensure that no contamination has managed to seep into it and secondly to ensure consistency for the quality of the product.

Surface water is another major area where TOC analysers have been used in process industry. Tank farms, storage areas and in oil marketing terminal type complexes where rain water is diverted to pass through the treatment works

Due to the nature of the process, some chemical plants have chemical contamination in large amounts of water. Not only does the water need to be cleaned, the chemical also needs to be reclaimed at the same time. This is often done by distillation where the water is heated and the chemical evaporates. The vapor is then cooled to collect the chemical. The TOC monitor can therefore be used at two areas in this industry. Firstly for the water that has had the chemical removed from it and secondly for detecting leaks in the cooling water pipe work.

TOC monitoring using UV Persulfate Oxidisation Technology

UV persulfate oxidisation is one of the most widely accepted technologies for today’s demanding need for online TOC monitoring. The sample is simultaneously exposed to persulfate and UV radiation and the resulting CO2 is purged by a carrier gas and detected by NDIR. The oxidation is significantly enhanced over UV radiations, by simultaneous ionisation of dissolved organics and production of highly reactive sulfate radicals and hydroxyl radicals. This process also ensures that all available organic carbon is oxidised without worry about optimisation.

The Forbes Marshall Total Organic Carbon (TOC) range of online analysers offers a highly reliable, quick and accurate means to determine, in real time, organic contamination in waste-water and effluent. These robust systems are supported by a diverse range of sample acquisition and pre-treatment systems that enable reliable monitoring of even the most difficult of effluent streams, in chemical, refinery, fertiliser and petrochemical industries.