The Latest News & Information from Colour Technologies Australasia and The Novasys Group

ENVIRONMENT EDITION

Volume E4 Issue 1 10 May 2005

Table of Contents

1. OilTrap Environmental introduces a New Generation of Washwater Treatment
2. The Compact Bioreactor; A Solution for High BOD/COD Industrial Effluent
3. Stormwater Pollution Prevention... Are Gross Pollutant Traps THE Answer?
4. Activated Sludge Respirometry for Wastewater Toxicity Testing and Tracking
5. Fun Stuff........

OilTrap Environmental introduces a New Generation of Washwater Treatment

Planes, trains and automobiles. Trucks, buses, trams, ships, bulldozers, tractors, cranes, conveyors, earth moving and mining equipment and shipping containers. All get dirty, all need washing and the dirty water needs, (or ought to be), cleaned up for re-use, or before discharge to the environment.

OilTrap Environmental, a leading manufacturer of electrocoagulation (EC) wastewater treatment systems, has introduced a new generation of electrocoagulation wash water treatment systems designed for wash water generated from washing vehicles and equipment.  The EP-1WR and EP-2WR are economically priced and easy to operate.

The ElectroPulse will process up to 750 litres per minute (LPM) of wash water and is of a quality that can be recycled or discharged to sewer. Average treatment cost is only $0.80 per 1,000 litres.

The ElectroPulse system uses electrocoagulation, an electricity-based technology for wash water treatment economically and on-site. The EC treatment process has proven successful in removing a variety of contaminants that are impossible or too expensive to be removed by filtration or chemical treatment systems. Amongst these contaminants are emulsified oil, TPH (Total Petroleum Hydrocarbon), suspended solids and heavy metals.  Generally heavy metals are reduced to a hydroxide, allowing sludge that is separated through the ElectroPulse treatment process, to pass a TCLP (Toxic Characteristic Leaching Procedure) test. 

The ElectroPulse wash water systems have a small footprint and are modular for accommodating to limited floor space. Systems are being used in many applications, including heavy equipment washing, marinas, military wash operations, forest products processing, aircraft refurbishing, motor vehicle auctions, equipment washing, and metal finishing and deburring.

Complete with on-board automation, the ElectroPulse system is fully automated, which dramatically reduces the cost and maintenance time often associated with on-site wastewater treatment systems. Also, there are no filters to clean or replace.

OilTrap Environmental, which has been manufacturing electrocoagulation water treatment systems since 1993, provides not only highly effective technology but a total solution approach through system design to meet your specific needs and requirements. OilTrap Environmental offers a FREE waste stream feasibility study using a representative sample of wastewater from your facility.

Contact Novasys for details.

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The Compact Dynamic Bioreactor; A Solution for High BOD/COD Industrial Effluent

The Compact Dynamic Bioreactor (CDB) is an innovative, modular biological wastewater treatment plant that has been originally developed as a low-cost but efficient solution to the requirements of small communities which are not yet connected to treatment plants. However, the system works very well with industrial wastewater with high BOD and COD loadings that may also be intermittent and seasonal, such as effluents from wineries and food processing plants.

The CDB incorporates a carrier material, Variopor, that consists of small cubes of open polymer foam. The open foam offers a large surface for micro-organisms to live upon and furthermore guarantees that the micro-organisms in the interior of the cubes are supplied with nutrients and organic compounds. Therefore, compared with conventionally used flocs of micro-organisms, which are active mostly at the surface only, the carrier is much more efficient. Reactions on the surface of the cubes is aerobic and in the interior, anaerobic. Combining both aerobic and anaerobic steps together, the treatment of wastewater will result in an efficient reduction of COD and total nitrogen.

Standardised reactor containers are available with a throughput of 500 l/h per reactor, however, any other size or kind of vessel can also be used. The reactors, are usually provided in pairs that can be arranged in parallel to enhance throughput and provide built-in redundancy.

Wastewater is supplied to the reactor after sieving to remove coarse waste. The water is mixed in the reactor with the carrier material. Energy is saved as no stirrer is required for mixing because the aeration tube is placed at one side at the bottom of the reactor. This results in the formation of a fast turbulent circulation of water together with the carrier cubes. This circulation also means that the supplied air is not going straight the way out, but is circulated throughout, thus enhancing the exchange yield of oxygen from air into the water.

No large clarification basin is required, because the biomass on the cubes can be kept back simply by a grid. Therefore the process is stable even during flood events and the biomass is not washed out. The cleaned, clear effluent leaving the plant is of high quality and can be used for irrigation. When the process is used for industrial wastewater the effluent can be recycled.

If the flow can be achieved by gravity, energy is  required for the pump supplying air only, in the range of 0.25 kWh for treating 1 m3/h of water. The plant can be run automatically, with a regular weekly check.  This wastewater treatment is odourless. Changes of flow rate, temperature or salinity do not have any negative influence on the high stability of this treatment process. Successful results have even been obtained for industrial wastewater with very high salinity, where conventional biological treatment does not work.

The technology is not limited to be used in sewage or industrial wastewater treatment plants. In a modified construction it can be used to clean rivers, lakes, lagoons or even sediments. For this application the carrier material Variopor will be captured in vertical arranged tubes, closed by a grid. The tubes have to be fixed in the water. By supply of air at the bottom of the tube water will be circulated through the tubes and the water will be cleaned by the micro-organisms living on the carrier material.

Contact us for more information.

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Stormwater Pollution Prevention...  Are Gross Pollutant Traps THE Answer?

The answer must be no. Gross Pollutant Traps are part of the answer only!

There has been a raft of publicity lately about the state of our rivers and waterways that does not make for happy reading or listening. One reaction to this has been to recommend the  installation of Gross Pollutant Traps to stop pollutants entering the stormwater drainage system.

By their very nature, Gross Pollutant Traps are designed to capture relatively large objects; bottles, cans, plastic bags and other relatively large objects. BUT... what about small objects, cigarette butt size and smaller? What about grease, oils and fuels such as  diesel and petrol? Sediments, dust, particles from brakes and motor vehicle engines that may contain heavy metals or asbestos? Animal urine and liquefied faecal matter?

There is no guarantee that GPT's will capture any of these smaller size pollutants unless they find their way permanently into the inside of the bottles, cans etc. that are thus trapped.

Then there is the question of cost; initial cost and maintenance. Most GPT's are not cheap and need to be cleaned out before they overflow. Retrofitting into older suburban streets or industrial sites may be impossible and/or prohibitively expensive.

The UltraTech range of disposable or reusable catch basin devices; DrainGuards, KerbGuards and GrateGuards that capture large and small debris down to sediment size, as well as hydrocarbons, are both cheap and effective. Users can choose the most appropriate device depending on the nature of the pollutant in their area. The disposable devices can allow water to flow into, but prevent any pollutant entering a particular drain, or capture up to 75% of ALL solid and undissolved pollutants in the stormwater stream, including hydrocarbons. The reusable devices are designed to capture large quantities of solid debris and sediments; up to 250kg per device. If spills occur, the UltraTech DrainSeals prevent any material escaping into the stormwater system.

Neither UltraTech nor ourselves pretend that the UltraTech devices provide the only answer to the problem of stormwater prevention pollution, but we do contend that they can play a significant part in a Total Stormwater Pollution Prevention Plan including Best Management Practice that includes Water Sensitive Urban Design, Gross Pollutant Traps, spill prevention and/or cleanup, preventing and detecting illegal connections to stormwater drains, education and enforcement.

At the very least, every company, municipality and contractor should maintain a program that includes good housekeeping, a preventive maintenance, visual inspections, a spill prevention and response policy, sediment and erosion control, and runoff management.

For information about UltraTech stormwater management products, or guidance on stormwater management at your site, please contact us.

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Activated Sludge Respirometry for Wastewater Toxicity Testing and Tracking

If industrial wastewater entering a treatment works contains toxic components, respiration rate and the rate of nitrification is inhibited.

When the sludge bacteria are inhibited, there is the possibility of toxicity carryover in the effluent that is discharged to receiving waters. With new environmental legislation being introduced to protect the natural environment, toxin discharge is now a serious concern for treatment plant managers.

In order to protect a treatment works from unknown toxic influents entering by sewer, an on-line early warning system may be required.

Tests with a laboratory respirometer are required to measure the toxicity of the diverted effluent in order to determine the safe rate of discharge into the aeration tanks. For tankered waste, laboratory tests on samples of the wastewater are carried out prior to its acceptance for treatment.

Large manufacturing companies treating their own waste want to minimise treatment cost - The respirometer is used to monitor the toxicity of effluent streams. In this way, discharge rates can be controlled to ensure that toxicity does not inhibit the activated sludge bacteria of the aeration tanks.

If toxicity is identified in a mixed sewage entering a treatment works, the problem for the plant manager is to track and identify the source of the toxicity. This can be done by sampling the effluent stream at various points in its length. This can be difficult, and it is sometimes easier to sample the effluents directly at source. The samples would be tested against the activated sludge of the receiving works, using the Respiration Inhibition Test or the Nitrification Inhibition Test.

For more details, contact us.

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Fun Stuff........

We have decided that life is too serious - All future editions of Novasys News will therefore contain a few things that we have found funny!

We hope that you too, get a smile from them.

If you come across anything that you think should go in this section, email us at sales@novasys.com.au and we'll include it!

So, here we go........

• Ever wondered why we have eyebrows?

            http://science.howstuffworks.com/question520.htm

• Mission Statement Generator

            http://www.dilbert.com/comics/dilbert/games/career/bin/ms.cgi

• English to American Dictionary

            http://english2american.com/index.html#index

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