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VATIS Update Waste Management . Jul-Aug 2006

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Waste Management Jul-Aug 2007

ISSN: 0971-5665

VATIS Update Waste Management is published 4 times a year to keep the readers up to date of most of the relevant and latest technological developments and events in the field of Waste Management. The Update is tailored to policy-makers, industries and technology transfer intermediaries.

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Contents

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IN THE NEWS

China profits from environmental protection industry

Chinas environmental protection industry generated 457.21 billion yuan (US$57 billion) in revenue and 39.39 billion yuan (US$4.9 billion) in profits in 2004, according to a government white paper titled Environmental Protection in China (1996-2005) issued recently. By the end of 2004, China had 11,623 enterprises, each with an annual sales income of more than 2 million yuan (US$249,000), engaged in environmental protection, employing close to 1.6 million workers, says the white paper issued by the Information Office of Chinas State Council.


During the Tenth Five-Year Plan period (2001-05), China conducted the national water pollution control technology and treatment project, and carried out R&D through such pilot programmes as motor vehicle emission purification, desulphurization of gas discharged by coal-fuelled boilers, disposal of solid wastes and clean production in key sectors. A green GDP accounting framework has also taken shape.


The government has carried out research on comprehensive ecological system assessment, ecological functional zoning, and the recovery and reconstruction of the frail ecological zones located in the western part of the country, thus shaping up a variety of technological patterns for treatment and a mechanism for large-scale demonstration and popularization in those zones. The white paper points out that after years of practice, China has formed an industrial system for environmental protection with a basically complete category and certain economic scale.


Website: www.english.people.com.cn 

Malaysia to bring law on solid waste management

Malaysia is working on a national solid waste management law that will better protect the environment. The Housing and Local Government Minister Datuk Seri Ong Ka Ting said that the solid waste management policy would consider landfills and recycling activities. I am taking a closer look at the solid waste management in the United Kingdom and its solid waste facilities as an input before we finalize our own national policy soon, he told the press during a visit to the United Kingdom. The Minister will also visit Switzerland to gather more information on that countrys environmental conservation.


A master plan on solid waste management will soon be presented to the Cabinet, the Minister said. He said that the National Technical Committee on Technical Evaluation on Solid Waste Management had discussed what was suitable for Malaysia and was in the midst of preparing a master plan. The technical committee consists of representatives from the local government, Natural Resources and Environment Ministry, Science, Technology and Innovation Ministry and the Health Ministry, besides academics from universities. 


Website: www.bernama.com.my 


www.thestar.com.my

Indias technology hub wakes up to e-waste problems

Bangalore, the technology hub of India, is witnessing an alarming growth in electronic waste, and it has become the site where environmentalists, representatives from industry, manufacturers and the government are meeting to frame a system around management of e-waste. The city produces 8,000 tonnes of electronic waste annually. It seems the perfect place to begin and set an example for the country, which produces anywhere between 80,000 and 150,000 tonnes of electronic waste annually.


India has its own unique processes. While what the legal recyclers, most of the industry and government leaders are talking about would deal with business to business transactions of PCs and peripherals, a much larger question is: who will help the common man dispose of batteries, PCs, gadgets and electronic items safely? The answer is kabaadi-wallahs (rag pickers), say environmentalists. Their skills, expertise and knowledge of materials could be used in initial collection and sorting of electronic waste. Their role could be enhanced and they could be part of a stable ecosystem, some say.


Stability can be guaranteed only if governed well centrally, says the Manufacturers Association for Information Technology (MAIT), the apex body representing IT hardware, training, design, R&D and associated services in India. MAIT wants more involvement from everyone, beginning with the government, to each of the nine industries that contribute to electronic waste, and entrepreneurs.
There is a need for, at the very least, 8-10 legal recycling plants, but the country has only a couple Eparisara and Trishyiraya Recycling India. Mr. P. Parthasarathy, Director of Eparisara, feels that each metro needs 2-3 plants, each with a processing capacity of 10 tpd. Right on cue, domestic and international entrepreneurs such as the Singapore-based recycler Cimelia Resource Recovery alike are interested in setting up plants in the country. It is hoped that the presence of international plants, along with the native ones, would generate a stable ecosystem for e-waste disposal in the country. Cimelia is in discussions with state governments to set up a plant in South India within the next eight months. Cimelia also plans to immediately begin a pre-processing facility that can take up e-waste from MNCs.


Website: www.thehindubusinessline.com

Pollution costs 10 per cent of Chinas GDP

Pollution problems are costing China more than US$200 billion a year, a top official has said,calling for stronger action to balance environmental protection against economic development. Environmental damage is costing the government roughly 10 per cent of the countrys GDP, estimated Mr. Zhu Guangyao, deputy chief of the State Environmental Protection Agency. Chinas environmental picture is worsening and allows for no optimism, he said while issuing the report Environmental Protection in China (1996-2005), which described the situation as grave.


The conflict between protecting the environment and encouraging development is becoming serious, and a shortage of resources, a fragile ecological balance and insufficient environmental protection capacity are becoming critical problems that hinder development.


Environmental protection must therefore become a brake now on Chinas economic macro-control policies and play a more prominent role in the approval process for large construction projects. Projects that over-develop land resources or affect the surrounding environment negatively will be cancelled, Mr. Zhu said.
China has established several main goals for environmental protection for the next five years. Among them, by 2010 environmental quality in key regions and cities will be improved and ecological deterioration will be brought under control even as rapid economic development continues. The total amount of major pollutants discharged is to be reduced by 10 per cent.


Website: www.chinadaily.com.cn

Pakistans air pollution crosses safe limits

The Economic Survey of Pakistan 2005-06 issued recently has said that the air pollution levels in the countrys most populated cities were among the highest in the world and were climbing, causing serious health issues. The levels of ambient particulates smoke particles and dust that cause respiratory diseases are generally twice the world average and more than five times as high as in industrial countries and Latin America, said the survey report.


The most serious issue of air quality in Pakistan is the presence of excessive suspended particulate matter (SPM) in the ambient air. Vehicles, industry, burning of solid waste, brick kilns and natural dust are the major sources of SPM. The key factors for air pollution in Pakistan were identified as: (a) rapidly growing energy demand; and (b) a fast-growing transport sector. In the cities, widespread use of low-quality fuel, combined with a dramatic expansion in the number of vehicles on roads, has led to significant air pollution problems. For example, the number of vehicles on the road has jumped from 0.8 million to about 4.0 million within 20 years, showing an overall increase of over 400 per cent.


Website: www.dawn.com

Viet Nam to tighten waste import control

The Prime Minister of Viet Nam has requested authorities to tighten control of import activities to prevent disguised import of waste into the country. The General Department of Customs was asked to coordinate closely with the Ministry of Transport to strengthen customs and transport management at seaports and monitor declarations to end illegal import of waste into Viet Nam.


The Prime Minister also asked the Ministry of Natural Resources and Environment to combine its efforts with those of authorities in border provinces to set and meet domestic and international regulations on the management and trans-border transport of waste, especially toxic substances. The Ministry has also been told to tighten its supervision and control of the implementation of regulations covering environmental protection with regard to import-export activities and to ensure that offenders meet the full extent of the law. 


Website: www.english.vietnamnet.vn

Singapore has more recycling plans

The National Environment Agency (NEA) of Singapore is planning to increase recycling for food, wood and horticultural products, though the countrys goal of recycling 60 per cent of its waste by 2012 looks to be on track, with both companies and households recycling more each year over the past three years.


NEA says that in the past three years, all JTC Corporation factories have joined in recycling efforts. In addition, the number of households that have taken up recycling has gone up by 10 per cent. Ms. Yang Hong, Senior Executive (Resources Conservation), says that by the end of 2007, every five blocks of flats will have a recycling bin or collection point and that NEA will give residents recycling bags as well as recycling bins.


Some local recycling companies hope that the government can follow the example of countries like Korea and Japan by legislating incentives for companies to recycle. NEA, however, says this measure would only lead to increased costs for companies which would then be passed on to consumers. Instead, it believes companies should look into how they can reduce industrial waste, for example, by encouraging major computer companies to recycle their own used products.


Besides reducing waste, NEA is also working to reduce air pollution when it incinerates garbage.


Website: www.channelnewsasia.com

Hong Kong tightens vehicle emission regulation

The Air Pollution Control (Vehicle Design Standards) (Emission) (Amendment) Regulation 2006 has been gazetted, the Hong Kong Environmental Protection Department announced. A spokesman for the Department said that the Amendment Regulation would tighten further the emission standards for newly registered heavy-duty vehicles and motorcycles in tandem with the European Union.


To reduce vehicle emissions, Hong Kong has been introducing the most stringent motor vehicle fuel and emission standards as soon as they can be made available to the local market. On 1 January 2006, we started in phases implementing Euro IV standards for light-duty vehicles weighing up to 3.5 tonnes, he said. The Amendment Regulation aims to tighten the emission standard for the remaining vehicle class (i.e. motor vehicles weighing above 3.5 tonnes) to Euro IV level from October 2006. It also requires all newly registered motorcycles to comply with Euro III emission standards from January 2007. The Amendment Regulation is to be tabled at the Legislative Council on 24 May 2006 for negative vetting. Based on the approval of the Council, the amendments will take effect on 1 October 2006.


Website: www.news.xinhuanet.com 

Vietnamese get advice on clean forms of industry

A company that gives advice on energy savings and pollution reduction has opened office in Ho Chi Minh City. The Viet Nam Cleaner Production Centre (VNCPC), which has operated in Viet Nam for eight years, helps companies increase their competitiveness by reducing production costs and pollution, said Mr. Phan Minh Tan, vice director of the citys Science and Technology Department.


The centre has given seminars in 19 cities and provinces, trained 6,000 people and helped position cleaner production on the policy agenda by making contributions to the National Environment Strategy 2000-2010. As a result, companies have invested US$1.8 million in implementing recommendations. This outlay has helped firms cut yearly costs of about $7.5 million and reduce annual water consumption by 7.3 million cubic metres, chemical use by 4,500 tonnes and energy consumption by 75 million kWh. The centre will also cooperate with the Energy Conservation Centre in advising authorities from the central province of Khanh Hoa to the southern province of Ca Mau.


Website: www.vietnamnews.vnagency.com.vn

China closes down over 2,600 polluting enterprises

Over 2,600 enterprises were closed down in China for having caused serious environmental pollution and violated industrial policies in 2005, according to a white paper entitled Environmental Protection in China (1996-2005) issued by the Information Office of the State Council. The white paper also says during the Ninth Five-Year Plan period (1996-2000), the State closed down 84,000 small enterprises that had caused both serious waste and pollution.


In the period 2001-04, the State issued directories listing the backward production capabilities, technologies and products that should be eliminated. More than 30,000 enterprises that had caused high pollution and wasted resources were winnowed out, says the white paper. Eight industries that consumed large amounts of resources and caused serious environmental pollution iron and steel, cement, electrolytic aluminium, iron alloy, calcium carbide, coking, saponin and chromic salt were rectified, and the construction of over 1,900 projects was stopped or postponed.


So far, over 5,000 enterprises in the sectors of chemicals, light industry, power-generation, coal, machinery, and building materials have passed the examination for clean production. More than 800 enterprises and 18,000 products of diverse types and specifications have received environmental labelling certification, says the white paper.


Website: www.english.people.com.cn

PLASTIC WASTES

First evidence that tough plastic can be biodegraded

A recent study by scientists from University of Wisconsin-La Crosse has shown for the first time that a fungus can break down the phenolic resins widely used in plastic formulations. The finding could make it easier to recycle the synthetic polymers, which are known for their durability and resistance to attacks by termites and fungi.


Phenolic resins are commonly used as industrial adhesives and in heavy-duty automotive parts such as the plastic trim on car bodies and the containers that hold air filters. The resins are formed when phenol and formaldehyde are cured at a high temperature and pressure in the presence of catalysts, so that the molecular chains form an interlocking 3D structure that is hard to break. As a result, they cannot be melted and remoulded like other plastics, such as polyethylene and polyvinyl chloride.


White-rot fungus is known to decompose organic pollutants such as DDT, TNT, PCBs and dioxins, and can be used to clean up these toxins from the environment. It produces enzymes called ligninases, which can break down lignin, the compound that makes up the dry part of wood. The researchers tested whether the fungus could also degrade phenolic resins, which have a molecular structure similar to that of lignin. They used a generic industrial formula to prepare the polymers and placed resin chips in cultures with the fungi.


The researchers first realized that the white-rot fungus was degrading the phenolic resin chips when their colour changed from yellow to a light pink, the colour of the phenol and formaldehyde subunits used to make the resins. They confirmed the presence of those subunits by gas chromatography/mass spectrometry and by locating pockmarks on the surface of the resin chips with scanning electron microscopy.


Website: www.pubs.acs.org

Fractional depolymerization technology

Global Finest Technologies, Australia, has introduced a patented system for converting waste oils, plastics and other recyclables into diesel oil. The fractional depolymerization technology is a pressureless, closed fluid process, with no harmful emissions (no dioxins, no furans). The low-temperature (maximum 420C) process has an average yield of 10,000 litres of diesel from 12 tonnes of input.


The decentralized plants can produce more than 500 litres of diesel per hour at the production cost of about 0.20/litre. Among the other advantages of the process are: yield of high-quality fuel, possibility to generate additional electric energy and heat, positive energy balance and high efficiency (up to 90 per cent depending on input material). In conventional high-temperature depolymerization systems, PVC and PET pose problems because they include chlorides and other materials, which cannot be handled or disposed safely at those high temperatures. In the Global Finests system, chloride ingredients are neutralized in the fluid system itself.


The small size of the plant makes decentralized processing possible on site where the raw materials
exist, thereby reducing and keeping potentially expensive transportation costs in check. The reactor component has base dimensions of 12 6 m, while the overall height of the plant is 9.5 m. For safety reasons, the entire plant stands in a safety tub, which catches liquids from any possible leakages.


Contact: Global Finest Technologies, Australia. Tel: + 61 (415) 504 999


E-mail: info@globalfinest.com


Website: www.globalfinest.com

Machines for plastic recycling

Hangzhou Holin Plastic Machinery Co., China, offers three models of plastic recycling machines. FST-130/120, HLFSJ-130/100 and HLF SJ-150/120 machines are mainly used for recycling high-foaming polystyrene and polyethylene products into grains. They are also used for recycling empty containers and films. The first-grade extruder is capable of powerful feeding, while the second-grade extruder is an exhaust type extruder with varying diameter.


This machine is equipped with a breaker with wide inlet, material storing room, water tank and grain machine. It is easy to operate, and has stable performance and high throughput. It is ideal equipment for recycling waste thermoplastics.


Contact: Hangzhou Holin Plastic Machinery Co., Ltd., 58 Tongyun Road, Liangzhu Economic Development Zone, Yuhang District, Hangzhou City, Zhejiang Province, China 311112. Tel: +86 (571) 8874 7709; Fax: +86 (571) 8874 7711.


Website: www.holin-machine.com

New plastic recycling plant

Suzuka Fuji Xerox Co., Japan, has commenced operations of its new plastics recycling plant with a capacity to recycle nearly 2,300 tonnes of used plastic annually. The newly established plant will clean, crush, mix with an auxiliary agent and make into granulated pellets plastic (styrene) from used OA equipment as well as home appliances. The recycled plastic will then be delivered to the market through materials manufacturers for reuse as a raw material for making same type of products.
Normally, the ratio of used plastic in recycled plastics is kept down to around 25 per cent, in order to keep the functionality and quality of the plastic intact. However, by combining Fuji Xeroxs uniquely developed Repelle auxiliary agent with the used plastic, it is possible to recover the properties of the plastic and thus eliminate the need to add virgin plastic. By using Repelle agent, plastics can be recycled into expanded polystyrene such as cushioning material and food trays without damaging the physical properties. Further, this recycling process reduces carbon dioxide emissions to one-tenth.


Website: www.fujixerox.co.j

Recycling of thermoplastic industrial waste

The X:GRAN 165, from Next Generation Recycling Maschinen (NGR) in Austria, is a giant recycling line that recycles 1,500 kg per hour of thermoplastic industrial waste. Its large hopper volume of 4 m3 and a cutter shaft of 1.8 m allow the machine to shred and re-pelletize large thermoplastic bales without any pre-treatment or handling.


NGR X:GRAN 165 Machines are typically modular built. That means depending on the application, the extruder, screen-changer as well as the pelletizer can be changed. Operation is via a 12 inch touch screen (optional PLC-maintenance via modem or Ethernet-connection is available). Space-saving water-cooled drives is a special feature of NGR X:GRAN 165.


Contact: Next Generation Recycling Maschinen, A-4614 Marchtrenk, Austria. Tel: +43 (7243) 58577-41; Fax: +43 (7243) 58577-2


E-mail: hubertus.neef@ngr.at


Website: www.ngr.at


Website: www.recyclinginternational.com

Organo-catalytic PET polymerization

In the United States, the Stanford University and IBM researchers have jointly invented an organo-catalytic, environment-friendly process of depolymerizing (recycling) polyethylene teraphthalate (PET). Currently recycled polymers are generally not of high quality and contain impurities and metals that limit their use. The patented process is a method for depolymerizing these polymers to provide high-quality recycled material substantially free of metal contaminants. This allows the recycled material to be used, thus saving costs while complying with the law.


The method depolymerizes a polymer containing electrophilic linkages in the presence of a catalyst and a nucleophilic reagent. The reaction can be carried out at a temperature of 80C or less, and involves the use of an organic, nonmetallic catalyst, thereby ensuring that the depolymerization product(s) are substantially free of metal contaminants. The depolymerization reaction can be carried out at a temperature ranging from the ambient temperature to 60C. The method provides an important alternative to current recycling techniques such as those used in the degradation of polyesters, polyamides, etc. An important application of this method is in the depolymerization of polyesters, including homopolymeric polyesters (in which all of the electrophilic linkages are ester linkages) and polyester copolymers (in which only a fraction of the electrophilic linkages are ester linkages).


Website: www.ibm.com

BIOMEDICAL / HEALTHCARE WASTES

Processing of medical waste

North American Power Company, the United States, has developed a continuous processing technology for treating wastes, including medical wastes. It employs the Thermal Recovery UnitTM (TRU), which has a retort chamber that receives solid waste from conveyor, screws or buckets through an airlock system. Sludge and liquids are pumped into the retort chamber by a progressive cavity pump. Solid and liquid wastes can be processed simultaneously. TRU then heats waste materials externally to temperatures of 540-1,010C in an annular chamber outside the retort. Waste materials are never incinerated, but gasified in the chamber by continuous exposure to indirect high temperatures and heat.


Waste materials are continuously loaded and conveyed through the retort chamber at varying rates depending on the composition of the wastes being gasified. The wastes remain in the chamber until all volatile materials are gasified and drawn into a thermal oxidizer chamber and are destroyed by combusting with oxygen. Remaining solids are discharged from the retort through air locks to ensure that oxygen is not drawn back into the retort. The discharged materials are sterile and non-leachable.


Reductions up to 95 per cent from the initial waste material volume can be achieved by the system.
Emissions other than carbon dioxide and water are rarely found in concentrations that exceed the most stringent air emissions criteria. Though the thermal oxidizer controls nearly all air emissions, the contents and concentrations are partly dependent on waste stream. Therefore, when the wastes are not completely predictable, the system will be fitted with an appropriate scrubber.


Contact: Ms. Stephanie Conover, North American Power Company, 3471 W. Oquendo Road, Suite 102, Las Vegas, NV 89119, United States of America. Tel: +1 (702) 2709543; Fax: +1 (702) 740 4004


E-mail: sales@napower.com 


Website: www.napower.com 

Rotating autoclave for hospitals

The Rotoclave, from Tempico Inc., the United States, is a rotating autoclave system that employs a pressure vessel fitted with a unique rotating internal drum. Rotoclave is available in several models for on-site medical waste processing in small, medium or large hospitals and healthcare facilities.


The waste bags are automatically loaded unopened into the internal drum, which has angular surfaces and helixes designed to load and unload the waste as well as to agitate it thoroughly throughout the processing cycle. Once the vessel is fully loaded, the door is closed via a touch-screen operator panel and the automated processing cycle is started. The system will create an initial vacuum to extract any air present in the internal chamber which would otherwise prevent the effective and immediate heat-up of the waste to be processed.


After the initial vacuum is completed, heat and moisture are introduced using steam generated by the facility's boiler. The heat initially causes the bags to soften and, during agitation, to rupture and spill their contents within the rotating drum. The combination of high temperature, pressure and moisture, together with the unique method of agitation, ensures that all materials will contact the necessary sterilizing steam.


The presence of moisture, high heat and pressure during the continued processing causes pulpable materials to become repulped and for plastics to deform and shrink. This action decreases the material volume in the reactive environment of the Rotoclave by 50 per cent or more. Once the processing is complete, the fully sterilized materials are automatically discharged from the Rotoclave.


Contact: Tempico Inc., 1700 West Church Street, Suite C, Hammond, Louisiana, LA 70401, United States of America. Tel: +1 (985) 429 9929; Fax: +1 (985) 429-9740


E-mail: tempico@tempico.com

Plasma-enhanced melting system

The Plasma Enhanced MelterTM (PEM) system, from InEnTec Medical Services in the United States, is highly effective in processing a wide variety of waste streams, such as hazardous, medical, industrial, radioactive and municipal wastes. PEM uses heating from electrically conducting gas (plasma) in a special gasification system to convert wastes to valuable products. It ensures nearly total destruction of organic materials and very low emission of hazardous air pollutants.


In addition to providing cost effective, environmentally responsible treatment and extraction of value from waste, the PEM system can be used as part of a distributed power production system. Depending on the waste stream, the larger PEM systems can produce much more power than they consume. Because a portion of the fuel is waste, costs can be contained and kept competitive. These combined PEM-GENTM systems can solve two problems waste treatment and disposal and electricity supply in a simple, effective manner.


An alternative to electric power generation is to extract hydrogen from the syngas for local hydrogen-based transportation or fuel cell uses. Under this configuration, the PEM becomes a source of distributed hydrogen. InEnTec has demonstrated the production of hydrogen from syngas using a pressure swing adsorption ( PSA) unit with purity greater than 99.999%. The remaining carbon monoxide from the PSA tail gas can be used in an appropriately sized genset for power production.


Contact: Mr. David L. Farmer, President, InEnTec Medical Services LLC, 1935 Butler Loop, Richland, WA 99352, United States of America. Tel: +1 (509) 946 5700; Fax: +1 (949) 472 3713


E-mail: wjquapp@inentec.com


Website: www.inentec.com

Electro-thermal deactivation for medical wastes

In South Africa, Evertrade Medical Waste company, is set to revolutionize the countrys medical waste-disposal services by replacing incineration with a process called electro-thermal deactivation (ETD). Patented by Stericycle, the worlds largest provider of medical waste-management services, the ETD process uses low-frequency radio waves and an imposed high-energy field to inactivate the medical waste and destroy pathogens, without combusting any of the materials. As the microbial level of the processed waste has reduced by six logs, it can be safely recycled. ETD is most effective on materials that contain polar molecules such as water, which is the main constituent of micro-organisms.


Polar molecules have an asymmetric electronic structure and tend to align themselves with an imposed electric field. When the polarity of the applied field changes rapidly, the molecules try to keep pace with the alternating field direction, thus vibrating and, in the process, dissipating energy as heat. The electric field created by ETD causes high molecular agitation and thus rapidly creates high temperatures within the microbial cell, thereby causing it to rupture and die. All of the molecules exposed to the field are agitated simultaneously and, accordingly, heat is produced evenly throughout the waste instead of being imposed from the surface as in conventional heating.


This phenomenon, called volumetric heating, transfers energy directly to the waste, resulting in uniform heating throughout the entire waste material and eliminating the inherent inefficiency of first transferring heat from an external source to the surface of the waste and then from the surface to the interior of the waste material.


ETD uses a radio frequency that maximizes the inactivation of the physical medical waste, enabling the treatment process to eliminate pathogens while maintaining the temperature of the rest of the waste at temperatures below 95C.


Website: www.engineeringnews.co.za 


On-site destruction of medical waste

Antaeus Group, a company based in Maryland, the United States, has developed a system for the on-site destruction and sterilization of medical waste. The principle used in the Antaeus system is to liquefy batches of waste material with water. The waste is circulated in a mixing tank using a chopper pump to disintegrate it, producing a slurry. The recirculating slurry is heated with steam to fully sterilize the material. Typically 34 kg batches of waste material are treated in the Antaeus system. This is done with 570 litres of water. A typical cycle lasts 30 minutes.


Antaeus is trying out a KP screw press with the system. The function of the screw press is to filter and dewater the suspended solids from the slurry. These solids are discharged as a cake mass that is dry and suitable for disposal along with other non-sensitive solid waste at the customers facility. At the same time, the filtrate press liquor is sufficiently clean for disposal in the sewer system. The simplicity, economy and reliability of the stainless steel screw press makes it well suited for these applications.


Contact, Antaeus Group, 1 North Park Drive, Suite 108, Hunt Valley, Maryland 21030 United States of America. Tel: +1 (410) 527 9280; Fax: +1 (410) 527 1251.


Website: www.vincentcorp.com

PERSISTENT ORGANIC POLLUTANTS

Reductive dehalogenation

Tribochem, Germany, offers DCMR technology, a reductive dehalogenation process to remove polyhalogenated compounds. At the core of the technology is the simultaneous use of vibratory mills and reactors in one single operation to strip organic-bound halogen (chlorine) from the pollutant molecule with the help of added base metals (sodium, magnesium, aluminium) and a suitable hydrogen donor (alcohols, polyethers) as a harmless inorganic metal halide (chloride).


DMCR technology demonstrates that inside a vibratory mill several required important operation steps like conditioning, dispersing and mixing contaminated materials and added reagents, can be perfectly and effectively combined in one single operation. Pollutants can be eliminated at room temperature and in a short time. Small pilot-scale projects have been successfully carried out covering PCBs, HCH and DDT removal in contaminated soils, PCB degradation in transformer oils, as well as destruction of polyhalogenated pollutants in specific areas. Scaling up is currently under way.


Contact: Dr. Volker Birke, Tribochem, Georgestrasse 14, D-31515, Wunstorf, Germany. Tel: +49 (5031) 67393; Fax: +49 (5031) 88 07


E-Mail: birke@tribochem.com


Website: www.tribochem.com

Base-catalysed destruction process

In the United States, the Pacific Northwest National Laboratory, the Environmental Protection Agency and the Naval Civil Engineering Laboratory have jointly developed the Base-catalysed destruction (BCD) process. The process has the potential to treat millions of tonnes of contaminated materials. It utilizes an inexpensive base in a chemical dehalogenation process that can detoxify polychlorinated biphenyls (PCBs), dioxins, pesticides and other hazardous organic materials in soils or other substrates without creating additional contaminants. When PCB-contaminated soils are treated by this process, chlorine and other halogen molecules are replaced by hydrogen, producing small amounts of sodium chloride and non-hazardous biphenyl. Ultimately, PCBs are detoxified at much less cost and with much greater public acceptance than incineration.


Website: www.procscieng.pnl.gov

Sunflower oil for PAH removal from soil

Researchers at the CAS Institute of Applied Ecology, China, have studied the potential of using sunflower oil in the removal of polycyclic aromatic hydrocarbons (PAHs). The results showed that sunflower oil had a great capacity to remove PAHs from contaminated soils, and sunflower oil solubilization can be an alternative technique for remediation of PAH contaminated soils.


Two litres of sunflower oil was added to the top of a column (33 cm x 21 cm) packed with 1 kg of PAH-contaminated soil. The oil was applied sequentially in two different ways: five additions of 400 ml or two additions of 1 litre each. The influence of PAHs concentration and the volume of sunflower oil on PAHs removal were examined. A soil respiration experiment was carried out and the organic carbon contents of the soils were measured to determine degradability of the remaining sunflower oil in the soil. Results showed that the sunflower oil was effective in removing PAHs from the two soils. More PAHs were removed by adding sunflower oil in two steps than in five steps, probably because of the slower flow rate in the former method. More than 90 per cent of total PAHs were removed from a heavily contaminated soil (a total 13 PAHs concentration of 4,721 mg/kg). A similar removal efficiency was obtained for another soil (a total 13 PAHs concentration of 724 mg/kg).


Website: www.ncbi.nlm.nih.gov 

Super bacterium for dioxins degradation

Scientists at the Graduate School of Agriculture, Kyoto University, Japan, have successfully developed a super bacterium capable of degrading dioxins two to three times faster than wild-type strains. This new strain of bacterium discovered by a research team led by Professor Kosaku Murata, belongs to the Sphingomonas species a gram-negative, rod-shaped chemoheterorophic bacterial group widely distributed in nature.


The new Sphingomonas sp. discovered by Kyoto scientists is able to degrade environmentally hazardous compounds, such as dioxins. The degradation capacity of the bacterium had to be increased substantially for use in bioremediation. The researchers identified that the bacterium has special membrane structures termed super channels, which form pits on the outer membrane. The microbes take in macromolecules into the cell through these pits. The research team analysed the molecular mechanisms of pit formation and succeeded in raising the degradation activity by incorporating pits into the membrane structure of dioxin-degrading bacterium. The engineered microbe gained stronger resistance to high concentrations of dioxins. Thus, the research group successfully developed a dioxin degrading super bacteria with high bioremediation potential.


Website: www.biospectrumasia.com

PCB-degrading bacteria associated with trees

A United States-Czech Republic joint research team has investigated the identities, degradation abilities and abundance of indigenous polychlorinated biphenyl (PCB)-degrading bacteria associated with five species of mature trees growing naturally in a contaminated site. The researchers from the University of Okalahoma in the United States, and the Institute for Chemical Technology and the Institute for Organic Chemistry and Biochemistry in the Czech Republic conducted the study to identify plants that enhance the microbial PCB degradation potential in soil.
Culturable PCB degraders were associated with every plant species examined in both the rhizosphere and root zone, which was defined as the bulk soil in which the plant was rooted. Significantly higher numbers of PCB degraders (2.7 to 56.7-fold higher means) were detected in the root zones of Austrian pine (Pinus nigra) and goat willow (Salix caprea) than in the root zones of other plants or non-root-containing soil in certain seasons and at certain soil depths. The majority of culturable PCB degraders at the site and the majority of culturable PCB degraders associated with plants were identified as members of the genus Rhodococcus by 16S rRNA gene sequence analysis. Other bacteria that degrade PCBs included members of the genera Luteibacter and Williamsia, which have not previously been shown to include PCB degraders.


PCB degradation assays revealed that some isolates from the site have broad congener specificities; these isolates included one Rhodococcus strain that had degradation abilities similar to those of Burkholderia xenovorans LB400. The apparent association of certain plant species with increased abundance of indigenous PCB degraders, including organisms with outstanding degradation abilities, throughout the root zone supports the idea that biostimulation through rhizoremediation is a promising strategy for enhancing on site PCB degradation.


Contact: Ms. Mary Beth Leigh, Centre for Microbial Ecology, Michigan State University, 540 Plant and Soil Sciences Building, East Lansing, MI 48824, United States of America. Tel: +1 (517) 355 0271; Fax: +1 (517) 353 2917


E-mail: leigh@msu.edu


Website: www.aem.asm.org

Adsorption process for waste gas purification

Linde Aktiengesellschaft, Germany, has received a United States patent for a process that purifies waste gases containing polyhalogenated compounds, in particular dioxins and furans, which waste gases accumulate, for example, in a garbage incinerator. In the process, the waste gases are directed through a filter that contains an adsorption agent. The adsorption agent, loaded with harmful substances, is transported in inert gas to another processing operation or to storage. During this transportation step, the polyhalogenated compounds are decomposed in heating zones (at temperatures of 250-450C) and cooling zones. Under these conditions, the primary dioxin decomposition is not followed by dioxin reformation.


This invention takes advantage of the fact that when the adsorption agent is transported under inert gas protection, ideal conditions exist for additional dioxin and furan decomposition, provided there are heating and cooling zones in the transport path. Since the adsorption agent during the transportation step has a relatively large surface area and is also mixed, a substantial decomposition of the dioxins and furans is achieved even with relatively short heating and cooling phases. The heating and cooling steps can be conducted by conventional radiation or conduction. Liquid nitrogen or low-temperature nitrogen gas is sprayed directly into the transport path to cool the adsorption agent rapidly.


Activated carbon, activated coke or a lime-carbon mixture is used as the adsorption agent. With these adsorption agents, harmful gases such as SO2, HCl, HF, H2S and NH3 basic amines and gaseous heavy metals can be selectively removed from the gas. Furthermore, fine powders having harmful substances, such as cadmium and lead, bound to them are also filtered out from the waste gas to be purified. The adsorbed dioxins are separated in a solid-gas phase system and fed to the flue gas purification system (wet scrubbers).


Website: www.freepatentsonline.com

INDUSTRIAL WASTEWATER

New biofilm reactor ideal for retrofits

The Moving Bed Biofilm Reactor (MBBRTM), from AnoxKaldnes of Sweden, has been proved to achieve dramatic reductions in biological and chemical oxygen demands in municipal and industrial applications. The MBBR process utilizes thousands of tiny, polyethylene biofilm elements to provide a home for a vast, highly active bacterial culture. These buoyant elements are kept in constant motion throughout the entire volume of the reactor, resulting in uniform, highly effective treatment.


The reactor employs a high-rate, fixed film process resulting in a plant footprint that is 20 per cent smaller than a conventional activated sludge system. This gives the customer the capability to retrofit existing tanks and triple the treatment capacity. MBBR process can be employed in the municipal (for nitrification and denitrification), chemical, petrochemical, pharmaceutical, pulp and paper, and food and dairy industries which have widely variable waste loading conditions. The process can be used to retrofit existing wastewater treatment plants for higher treatment capacity and/or meeting new effluent guidelines related to ammonia and total nitrogen.


Contact: AnoxKaldnes AB, Klosterngsvgen 11A, SE-226 47 Lund, Sweden.


Website: www.anoxkaldnes.com


Website: www.waterandwastewater.com

Rotating biological contactors treat mine wastewater

Pilot operations at tailings pond discharges in Canada and Africa show that the Rotating Biological Contactor (RBC) process developed by Envirex Products, a company of USFilter, the United States can be designed to economically and reliably treat wastewater generated by mining operations. The RBC process has been in operation in many different industries worldwide such as refineries, chemical plants and mines, in addition to hundreds of municipal wastewater treatment applications.


The Envirex RBC system is a cost-effective and environment-friendly way to detoxify hazardous cyanide tailings compounds that result from the leaching process. RBC is uncomplicated, easy to install and use, with performance proven around the world. It is considered one of the more efficient fixed film wastewater treatment technologies. Among the important operating benefits the RBC process has to offer are: consistent results, stable operation even with fluctuating input low energy consumption, and minimum maintenance and operator attention. It is well suited for secondary and/or advanced treatment in municipal or industrial applications.


Website: www.waterandwastewater.com

Advanced COD treatment system

The A-Hipo process, from Kankyo Engineering Co. in Japan, is an advanced wastewater treatment system designed to remove chemical oxygen demand (COD) and colours caused by organic compounds that do not biodegrade. Conventional COD treatment is by activated carbon absorption process or ozone oxidation process. Both these processes are relatively costly and do not produce sufficient results. The A-Hipo process, which is based on advanced COD treatment technology, is capable of treating a variety of COD substances, while offering ease of operation, high treatment efficiency and low running cost.


The process can be used to treat surfactants, lignin, humic acid, dyes, bile pigment, organic chlorine compound, cyanide, phenol-based cyclic compounds and other organic synthetic compounds. The operation cost of the A-Hipo process is 50-20 per cent that of the activated carbon absorption process. Typical COD reductions are: Chemical/coal 150mg/l 20mg/l; Pharmaceutical 240mg/l 40mg/l; Dye/bleaching 45mg/l 10mg/l; Pulp/paper 80mg/l 10mg/l.


The wastewater treatment system consists of an acidic coagulation process and a chemical oxidation process using hydrogen peroxide, one complementing the other to achieve highly effective and reliable treatment. The acidic coagulation process can effectively remove high polymer organic compounds that are not biologically decomposable. The chemical oxidation process oxidizes and decomposes various COD constituents, organic chloride compounds, phenol-based cyclic compounds and cyanide through the powerful oxidation effect of OH radical that is generated by the hydrogen peroxide-iron catalyst (Hipo) process (Fenton reaction).


Contact: Kankyo Engineering Co. Ltd., 1-9-8, Higashikanda, Chiyoda-ku, Tokyo 101-0031, Japan. Tel: +81 (3) 3862 1611; Fax: +81 (3) 3862 1617


Website: www.k-eng.co.jp


Website: www.nett21.gec.jp

Anaerobic process for phenol-laden wastewater

Armand-Frappier Institute (IAF), a component of the National scientific Research Institute (INRS) in Canada, has developed an anaerobic process (fixed film bioreactor) for treating phenol-containing industrial wastewater. The Institute has shown that the process can be used efficiently to reach the criteria established for petrochemical wastewater. It has also purified bacterium capable of performing carboxylation and dehydroxylation, the first two steps needed to degrade phenol under methanogenic conditions. This bacterium acts in association with a second bacterium that also has been isolated.


The enzymes that catalyse the carboxylation of phenol have been partially purified and characterized. INRS-IAF isolated a new anaerobic microbe called Desulfitobacterium frappieri PCP-1, which is able to dehalogenate PCP to produce 3-chlorophenol. The bacteria can dehalogenate several other aromatic and aliphatic compounds. The researchers have developed tools to detect the bacteria in the environment during the degradation process in soil and waste water.


Contact: INRS-Institut Armand-Frappier, 531, boulevard des Prairies, LAVAL, Quebec H7V 1B7, Canada. Tel: +1 (450) 687 5010; Fax: +1 (450) 686 5501


Website: www.iaf.inrs.ca


Website: www.strategis.ic.gc.ca  

Water recovery for electronics industry

Wastewater bearing mainly inorganic substances is treated by ion exchange units to recover water for reuse. Such water purification and reuse not only saves resources but also reduces the volume of effluent discharge. The process uses a combination of activated carbon and various kinds of ion exchange resins depending upon the nature of the wastewater. Organo Corporation or Japan supplies ion exchange water recovery systems for use in the electronics industry that manufactures semiconductors, silicon wafers and liquid crystals.


Organo water recovery plants can treat raw wastewater with an electric conductivity of 2,000 s/cm and a pH of 2-3 to purified water with an electric conductivity of 20 s/cm and a pH of 7-8 using activated carbon different types of ion exchange resins. The resins used include:
 
  • Weakly basic anion exchange resin (WBAER) to remove from feed wastewater acids, such as sulphuric acid;
     
  • Strongly acidic cation exchange resin (SACER) to adsorb and remove cations such as ammonia, sodium and potassium; and
     
  • Strongly basic anion exchange resin (SBAER) designed to adsorb and remove acids liberated in the upstream bed of the strongly acidic cation exchange resin.
     

Contact: Organo Corporation, 1-2-8, Shinsuna, Koto-ku, Tokyo 136-8631, Japan. Tel: +81 (3) 5635 5100; Fax: +81 (3) 3699 7030


Website: www.organo.co.jp


Website: www.nett21.gec.jp


Trickling filter for biological treatment of dye wastewater

In Greece, two researchers from the Department of Chemical Engineering, University of Patras, have developed and assessed the effectiveness of a biological trickling filter for the treatment of wastewaters produced by a company manufacturing organic dyes and varnishes. The combined wastewater effluent was fed to a pilot-scale trickling filter in two feeding modes, continuously and as a sequencing batch reactor (SBR). The biodegradability of the diluted wastewaters subjected to physicochemical treatment, using Ca(OH)2 and FeSO4, was initially studied using a continuously operated trickling filter.


The system efficiency ranged up to 60-70 per cent for a hydraulic loading of 1.1 m3/m2/day and up to 80-85 per cent for a hydraulic loading 0.6 m3/m2/day. A stable chemical oxygen demand (COD) removal efficiency of 60-70 per cent was achieved even with undiluted wastewater at a hydraulic loading of 1.1 m3/m2/day. The effectiveness of biological treatment of a mixture of the companys main wastewater streams was also examined. The micro-organisms developed in the trickling filter were able to remove COD levels up to 36,000 mg/l, under aerobic conditions at pH values between 5.5 and 8.0.
Depending on the operating conditions of the system, about 30-60 per cent of the total COD removal was attributed to air stripping caused by the air supply at the bottom of the filter, whereas the rest of the COD was clearly removed through biological action. The proposed biological treatment process, which was operated either continuously or even better in an SBR mode, appears to be a promising pre-treatment step for coping with dye manufacturing wastewaters in terms of removing a significant portion of the organic content.


Contact: Mr. M. Kornaros, Department of Chemical Engineering, University of Patras, 1 Karatheodori Street, 26500 Patras, Greece.


Website: www.ncbi.nlm.nih.gov

BIOREMEDIATION

Ex situ remediation of contaminated soil

Nishihara Environmental Sanitation Research Corporation Ltd. of Japan has developed a remediation system called Pan Reactor to move contaminated soil, quickly complete treatment using biological method and refill the excavation with the decontaminated soil. Pan Reactor can be used for the bioremediation of soil contaminated by oils (such as fuel oil and crankcase oil), plasticizers, insecticides and agricultural chemicals.


Contaminated soil is mixed with biomass which is tailored for degrading target soil contaminants, along with nutrients and any other additives found to improve either the completeness or rate of bioremediation. The mixture is placed in the Pan Reactor, which is controlled to provide the desired pH, moisture content and temperature. After bioremediation is completed, the soil is removed and refilled at the original excavation site or elsewhere. Pan Reactor is available in several configurations that meet different treatment objectives and site limitations.


Contact: Nishihara Environmental Sanitation Research Corporation Ltd., 3-6-18, Shibaura, Minato-ku, Tokyo 108-0023, Japan. Tel: +81 (3) 3455 4821; Fax: +81 (3) 3456 3643


Website: www.nishihara.co.jp 


Website: www.nett21.gec.jp

Aerobic bioremediation for PAH-laden soil

The DARAMEND technology, developed by Adventus Americas Inc. based in the United States, involves the addition of nutrients and proprietary organic amendments to optimize the rate of microbial activity in soils and sediments. Close control of the soil moisture content and aeration is achieved through irrigation and tillage. The technology was tested at two pilot-scale demonstration sites in Canada based on solid-phase aerobic bioremediation.


The first pilot involved the treatment of 100 tonnes of soil from a former Pintsch oil gasification plant. The second site involved the treatment of 150 tonnes of sediment affected by coal coking operations from steel manufacturing. Treatment started after a period of passive dewatering within the bioremediation cell. In both cases, total polycyclic aromatic hydrocarbon (PAH) concentrations decreased substantially, well below regulatory guidelines after adeuate days of treatment.


Website: www.clu-in.org

Enhancing oxidative bioremediation of chlorinated solvents

Scientists from the United States Geological Survey (USGS), along with industry partners, have undertaken a project to demonstrate the use of adding humic acids to ground-water systems to remediate chlorinated solvents. The project is based on the concept of electron shuttles, developed by Toxic Substances Hydrology Programme scientists and their university partners. It will demonstrate how that concept can be used as the basis for new clean-up strategies for environmental contaminants. USGS scientists are contributing to the design, oversight, and data interpretation of the project.


This project is testing ways to enhance bioremediation of chlorinated organic chemicals and avoiding the common problem of slowdown or stall by cis-dichloroethylene (cis-DCE) through the addition of humic acids to contaminant plumes. Humic acids act as electron shuttles that serve to enhance the activity of all available electron acceptors, particularly ferric iron. By enhancing the efficiency of this processes, it may be possible to increase the oxidation of cis-DCE and thus eliminate the cis-DCE slowdown or stall. Because electron shuttles are not used up, they may prove handy for bioremediation of chlorinated solvents.


Website: www.toxics.usgs.gov 

Microbe identification for bioremediation

The EvolverTM process, from CSIRO of Australia, is a patented technology that allows the identification from millions of naturally occurring micro-organisms capable of degrading a contaminant of interest. The approach uses sensitive computer controls, and uses a series of continuous on-line real-time probes to monitor and adjust a range of key factors that affect metabolism to enable a selective enrichment of the strains of micro-organisms that are best suited to degrade the test substrate. The discovery of several lead candidates and purification to a custom microbe occurs within three weeks.


CSIROs unique microbial library offers huge inherent diversity and couples with the on-line, real-time control of the discovery process to greatly enhance the chances of successfully finding suitable microbes. Evolvers flexible technology means that an enormous range of bio-contaminates can be tackled.


Contact: Dr. Michael Zachariou, CSIRO Molecular and Health Technologies, Bag 10, Clayton South, VIC 3169, Australia. Tel: +61 (3) 954 52321; Fax: +61 (3) 9545 2175


E- mail: michael.zachariou@csiro.au


Website: www.bio.csiro.au 


Two-step off-site bioremediation

In the United States, Waste Management Inc., the worlds largest solid waste services company, has developed a collection of innovative off-site remediation technologies to help companies deal effectively with contaminated soils.


The Two-Step Static System (TOSS) is a two-stage, solid-phase bioremediation technology that involves both anaerobic and aerobic treatment stages. First, soil contaminated with explosives is combined with a carbon source, an inoculum, vitamins and water to achieve anaerobic conditions. The resulting mixture is formed into a static pile or placed in a bermed construction or box to facilitate the chemical reduction of nitroaromatic and nitramine explosives. In the second stage, the anaerobically treated soil is combined with yard waste compost and built into an aerated biopile. The biopile is aerated by forced air conveyed through perforated piping buried within the pile or by turning the pile with a compost turner. TOSS has demonstrated TNT removal efficiencies of greater than 99 per cent.


Bio-In-A-Box is based on the same principle as TOSS, but is designed to operate indoors on a relatively smaller scale. The contaminated soil is moistened, mixed with nutrients and custom-grown microbes, and then placed in enclosed containers solid-phase bioreactors for incubation. The BioSite System is for the large-scale bioremediation of soils contaminated with a wide range of petrochemicals. It can also handle other contaminants, such as aliphatic chlorinated hydrocarbons, spent molecular sieve from packing towers, pesticides and wastes from chemical manufacturing.


Contact: Waste Management Inc., 1001 Fannin, Suite 4000, Houston, Texas, TX 77002, United States of America. Tel: + 1 (713) 512 6200.


Website: www.wm.com

Bioremediation by composting of oil refinery sludge

In Spain, a research team from the Department of Soil and Water Conservation and Waste Management of CEBAS-CSIC has ascertained the efficacy of low-cost composting technology as a bioremediation technique for reducing the hydrocarbon content of oil refinery sludge in semi-arid conditions. The sludge, with high total hydrocarbon content (250-300 g/kg) was produced in a refinery in Spain. The composting system, which involved open air piles turned over in a period of three months, proved to be inexpensive and reliable.


The influence on hydrocarbon biodegradation of adding a bulking agent (wood shavings) and inoculation of the composting piles with pig slurry (a liquid organic fertilizer that adds nutrients and microbial biomass to the pile) was also studied. The most effective treatment was the one in which the bulking agent was added, where the initial hydrocarbon content was reduced by 60 per cent in three months, compared with the 32 per cent reduction obtained without the bulking agent. The introduction of the organic fertilizer did not significantly improve the degree of hydrocarbon degradation.


Contact: Mr. J.L. Moreno, Department of Soil and Water Conservation and Waste Management of CEBAS-CSIC, P.O. Box 164, 30100, Espinardo, Murcia, Spain.


E-mail: jlmoreno@cebas.csic.es


Website: www.ncbi.nlm.nih.gov

Regeneration of granular activated carbon

Physico-chemical wastewater treatment processes that employ granulated activated carbon (GAC) would require a process to decontaminate and regenerate GAC. Nishihara Environmental Sanitation Research Corporation Ltd., Japan, has developed a granular activated carbon with sequencing batch biofilm reactor (GAC-SBBR) for the purpose. The GAC-SBBR is suitable for long-term remediation projects, in cases where the effluent strength is low and flow speed high. Used GAC, which is close to saturation with contaminants, is regenerated by desorbtion system. The contaminants released from GAC get mineralized by the sequencing batch biofilm reactor.


Contact: Nishihara Environmental Sanitation Research Corporation Ltd., 3-6-18, Shibaura, Minato-ku, Tokyo 108-0023, Japan. Tel: +81 (3) 3455 48 21; Fax: +81 (3) 3456 3643


Web-site: www.nishihara.co.jp


Website: www.nett21.gec.jp

AIR POLLUTION CONTROL

High-energy Venturi scrubber

The high-energy Venturi scrubber, from Croll-Reynolds Clean Air Technologies in the United States, is suitable to capture small particles between 0.5 and 3 microns in size. Its effectiveness in the sub-micron range is critically dependent on gas-side pressure drop. This design requires little or no maintenance. Energy from a high-velocity, dust-laden gas stream is used to atomize a liquid stream. Cyclonic gas flow in the separator drives the dust-laden liquid to the outside wall. The liquid is collected and returned to the sump.


Contact: Croll-Reynolds Clean Air Technologies, Six Campus Drive, Parsippany, New Jersey 07054, United States of America. Tel: +1 (908) 232 4200; Fax: +1 (908) 232 2146


E-mail: www.info@croll.com 


Website: www.pollutiononline.com

Tackling mercury in coal-fired power plants

A new technology for removing mercury from the emissions of coal-fired power plants has the added benefit of simultaneously reducing other pollutants. Tests conducted at coal-fired power plants show that the technology can reduce mercury emissions at higher rates and lower costs than current methods, according to its developers, Chem-Mod LLC, the United States. The ability of the technology to simultaneously remove the other pollutants associated with burning coal sets it apart from the rest.


The toxic mercury from the coal released into the atmosphere is in either the elemental (Hg0) or the oxidized (Hg2+) form. However, activated carbon injection and flue gas desulphurization (also known as the scrubber technique) have difficulty capturing Hg0 because of its low reactivity. The Chem-Mod system is able to capture Hg0 by using a liquid sorbent to oxidize it to Hg2+ or trap it on its surface. A second, powder sorbent captures SO2 and heavy metals. The two sorbents combine to trap the emissions in a ceramic-like matrix that is locked into the fly ash.


The new system removed up to 86-98 per cent of the mercury in week-long tests with different bituminous and sub-bituminous grades of coals. In addition, the system cut SO2 emissions by 40-75 per cent and those of arsenic, chloride and heavy metals by 75-90 per cent. The Chem-Mod technology also costs less than scrubbers, which will be its main commercial competitor.


Contact: Chem-Mod Headquarters, P.O. Box 214, Stow, Ohio OH 44224, United States of America. Tel: +1 (866) 846 4789; Fax: +1 (866) 26001 19


E-mail: info@chem-mod.com


Website: www.pubs.acs.org

Rotation scrubber

Lenntech Water Treatment & Air Purification Holding, the Netherlands, offers rotation scrubbers for dust scrubbing. In the rotation scrubber, the wash water is dispersed in small drops using a fast-rotating spray disk, thereby ensuring a large contact area between water drops and gas. The gas is fed tangentially into the scrubber chamber where, through centrifugal force and rotation, dust particles are dragged to the walls. The separated dust is washed down and drained. The rotation scrubber can remove particles up to 0.1 m.


The advantages of rotation scrubber include:
 
  • Wash water can be recycled;
     
  • It has low pressure drop;
     
  • No pollution or clogging of the wash section;
     
  • It can be used for cleaning viscous, explosive as well as inflammable substances;
     
  • Very high output also for sub-micron particles;
     
  • Insensitive to fluctuating gas flows; and
     
  • Self-cleaning
     

The rotating scrubber, however, has relatively high energy usage, capital outlay and maintenance costs.


Contact: Lenntech Water Treatment & Air Purification Holding B.V., Rotterdamseweg 402 M, 2629 HH Delft, The Netherlands. Tel: +31 (15) 2610 900; Fax: +31 (15) 2616 289


E-mail: info@lenntech.com


Website: www.lenntech.com


New technology for reduction of NOx emissions

Thermal Energy International Inc., Canada, has developed a new technology, which is at the core of its THERMALONOxTM solution. The technology is a cost-effective alternative process to effectively reduce nitrogen oxide (NOx) emissions at coal-fired power plants and other industrial boiler/burner applications.


Thermal Energys new system to generate ozone is fundamental to the chemical reaction required to remove NOx from the flue gas. Extensive bench tests have shown that the new process generates significant quantities of ozone. The company has started further R&D work to integrate the new technology into the total THERMALONOx solution. This will include additional bench tests and the establishment of an R&D test site, with the eventual goal of establishing an industrial-scale demonstration site.


Website: www.money.cnn.com


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