VATIS Update Waste Management . Jul-Sep 2012

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Waste Management Jul-Sep 2012

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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India implements e-waste disposal scheme

India’s Ministry of Environment and Forests (MoEF) is implementing a scheme to provide financial assistance for setting up treatment, disposal as well as storage facilities for hazardous wastes and integrated recycling facilities for e-waste on public-private partnership mode. A survey carried out by the Central Pollution Control Board (CPCB) had estimated that 147,000 t of e-waste was generated in India in 2005. This was expected to increase to about 800,000 t by 2012. Maharashtra, Tamil Nadu, Andhra Pradesh, Uttar Pradesh, West Bengal, Delhi, Karnataka, Gujarat, Madhya Pradesh and Punjab are the top 10 states generating about 70 per cent of the total e-waste. There are about 75 authorized and registered e-waste recyclers with recycling capacity of about 246,000 t/y of e-waste.

MoEF-notified e-Wastes (Management and Handling) Rules, 2011, for proper management and handling of e-waste came into force from 1 May 2012, according to a written note to the Indian Parliament from Ms. Jayanthi Natarajan, Minister of State (Independent Charge) for Environment and Forests. As per these rules, e-waste means waste electrical and electronic equipment – whole or in part or rejects from their manufacturing and repair process – that are intended to be discarded. The concept of extended producer responsibility (EPR) has been enshrined in these rules. As per these rules, producers are required to collect e-waste generated from their end of life products by setting up collections centres or take-back systems individually or collectively.

E-waste recycling can be carried out only in facilities authorized and registered with Pollution Control Boards/Pollution Control Committees in states. Waste generated is required to be sent or sold to any registered or authorized recycler or re-processor having environmentally sound facilities. Guidelines for Environmentally Sound Management of E-waste published by CPCB details the approach and methodology for environmentally sound management of e-waste.

Philippine guidelines on temporary disposal of mercury waste

In the Philippines, the Centre for Health and Development (CHD), Department of Health (DOH), Cordillera Administrative Region (CAR), has issued detailed guidelines on the temporary disposal of mercury wastes in health facilities. The initiative is part of the government’s efforts in containing toxic wastes that pose danger to health and the environment. The set of guidelines was issued by DOH to temporarily contain phased-out medical devices. There are no accredited treatment, storage and disposal (TSD) facilities set up by the Environment and Management Bureau of the Department of Environment and Natural Resources (EMB-DENR) for mercury in sphygmomanometers and thermometers. As such, storage facilities would take some time before these are made available to health facilities all over the country.

The guidelines provide guidance for appropriate temporary on-site storage of mercury-containing obsolete medical devices and other waste materials in healthcare facilities. It also mandates the heads of facilities in ensuring a dedicated and secure storage area for mercury. It is also integrated in the PhilHealth licensing and accreditation of health facilities on the enforcement of the total phase-out of the use of mercury-laden medical devices such as thermometers and sphygmomanometers. It also indicates the provision of technical assistance of government institutions and allotment of funds for the purpose. Furthermore, it mandates shifting to the purchase and use of compact fluorescent lamps and other energy-efficient lighting systems.

Japan supports Sri Lanka in wastewater treatment

Japan has extended its support to improve wastewater management technology in Sri Lanka’s industrial sector. The Open University of Japan would collaborate with the Central Environmental Authority (CEA) of Sri Lanka to improve wastewater treatment. The University’s agreement to share its technological expertise on this aspect with Sri Lanka in the coming years was revealed at a recent workshop on Wastewater Management in Colombo with the participation of a Japanese team.

Addressing the workshop, Mass Media and Information Ministry Secretary Dr. Charitha Herath briefed on the measures taken by the Sri Lankan government to maintain exact standards on industrial wastewater treated and released to the environment. Dr. Herath revealed that wastewater treatment mechanisms have been made compulsory for factories and industries operating within the country. CEA has been guiding the industrial sector in the adoption of suitable technology to fulfill this requirement. Prof. Mitsumasa Okada, a water management expert from Japan, stated that the awareness on the latest trends in the world on wastewater management must be considered by countries in the Asian region, as it has become a key issue in the region.

Pilot recycling and composting projects in Pakistan

The United Nations Human Settlements Programme (UN-Habitat) and the United Nations Economic and Social Commission for Asia and the Pacific (UNESCAP) have launched a solid waste management pilot project in some cities of Pakistan. To initiate the project, Integrated Resource Recovery Centres (IRRCs) – decentralized community-based recycling and composting facilities – will be built in the cities of Islamabad, Karachi, Rawalpindi and Mardan. According to United Nations-Habitat, IRRCs can be built and run at low costs by utilizing limited mechanical technology and ensuring low operational costs with minimal equipment breakdowns, while creating job opportunities.

Pakistan is reported to produce an average of 54,888 tonnes of solid waste per day, the proper treatment of which is hampered in most of the cities because of poor town planning and ever-increasing populations. According to United Nations-Habitat, none of the cities have a proper solid waste management system and there is a void of a planned procedure for the collection of wastes through to its disposal. This results in clogged drains and polluted ponds that are breeding grounds for mosquitoes and flies. Cities also lack solid waste disposal units.

The four cities are better planned than most of the cities in the country. They have adequate municipal committees, but United Nations-Habitat stated that they still lack the resources for proper waste disposal systems. They have inadequate collection points, transportation facilities and disposal units, despite the size of the cities. Only half of the waste is properly disposed off, United Nations-Habitat stated. The project aims to develop an efficient waste collection and transfer system that will be associated with the IRRCs.

Chinese plastics recyclers unite

A consortium of more than 50 Chinese plastics recycling companies, China Scrap Plastics Association (CSPA), has been established recently in Beijing, China. CSPA hopes to support development of China’s plastics industry. It will function as a catalyst for innovation by setting up a communication platform for the industry and the Chinese government. CSPA is determined to resolve issues currently curbing the potential of the scrap plastics industry and has pledged to invest in initiatives to increase the use of recycled plastics as a less harmful resource than virgin material. The organization has already provided specialist views on several relevant ‘hot topics’ such as improved access conditions for imported scrap plastics in light of current problems concerning smuggled material.

Successful models in pollution control

In India, the Central Planning Commission (CPC) conducted a study to identify successful models of implementation of environmental policies and programmes in states and union territories. The study was carried out for CPC by Prestels, an environmental safety study agency. Many states performed well in controlling air pollution and in implementing hazardous waste rules and batteries rules. However, in implementing municipal solid waste rules, their performance is not so noteworthy.

The CPC study points out that industrial states like Andhra Pradesh, Karnataka, Madhya Pradesh and Jharkand are relatively better than other lesser industrialized states in enforcing pollution control norms. Out of the 88 industrial clusters, 43 are critically polluted and 33 are severely polluted. The study and the ranking of the states are based on the Environmental Performance Index (EPI) and Comprehensive Environmental Pollution Index (CPEI) criteria formulated by CPC. In the air EPI score, Kerala, Goa, Pondicherry and Mizoram share the first rank with 1 point each, whereas the average performance across states is 0.826. But in the water EPI, the national average score is 0.5353. Himachal Pradesh tops the list in this category with 0.7561 EPI score. In the waste EPI, the national average is 0.584. In treatment efficiency of hazardous waste, Karnataka, Chandigarh, Haryana, Pondicherry and West Bengal rank fifth.

Thailand targets 80 per cent factory waste compliance

Authorities in Thailand expect 80 per cent of all factories in the 20 categories to dispose their waste legally by the end of 2012. In 2011, the Industrial Works Department had set a target for all industrial waste to be legally disposed by the end of August that year. However, only 70 per cent of the target could be achieved, said the Deputy Director-General, Mr. Phongthep Jaruampornparn. To raise the proportion to 80 per cent by the end of 2012, the Department will ask each province to come up with plans on how to achieve the goal. Thailand’s Industrial Waste Management Bureau will be given a larger role in supervising hazardous waste, while provincial authorities will take care of general waste by focusing on the capabilities of recycling plants.

The number of factories covered will be increased by adding five more categories to the 15 in 2011. Among the 15 target categories are 1,781 plants that generate large amounts of industrial waste such as those making fertilizers, paint, ink, paper, chemicals and petroleum products. The five additional categories to be monitored are 1,427 plants outside industrial estates including basic iron and steel industry and non-ferrous metal basic industry. They also include painting or colour- or lacquer-spraying, and car-tuning workshops.

China to enforce regulation on imports of recycled plastics

In its bid to crack down on the quality of plastic imports, the government of China has directed plastic recycling companies to report imports that are banned or contravene environmental protection rules. The announcement was made by China’s Ministry of Environmental Protection, Ministry of Commerce and the National Development and Reform Commission. China will strictly enforce regulations that prohibit the import of unwashed, post-consumer plastics and ban the transfer of imported waste to a company other than that allowed under the import licence. Further, companies will not be allowed to sell unwashed leftover plastic from sorting of imported plastic and paper.

Local environmental protection agencies will inspect plastic recycling companies and publish the list of qualified recyclers and the list of companies that fail inspections. From 1 January 2013, only companies that have qualified will be able to import plastics. New policies were announced also for both domestic and imported plastics, including disallowing recycling in residential areas and a ban on plastics processing without sufficient water treatment facilities. The new rules will be implemented from 1 October 2012.

Malaysia embarks on pollution-mapping project

The Department of Environment of Malaysia is conducting a pollution-mapping drive of rivers to identify major sources of water pollution in the country as part of the government’s efforts to rehabilitate the nation’s degraded waterways. The Minister of Natural Resources and Environment, Mr. Douglas Uggah Embas, said: “In Malaysia, the polluted areas are mainly where big settlements, big cities, towns and industrial areas are located. There are also a lot of illegal manufacturing areas that are contributing factors to the sewage and solid waste problems.”

The rapid pace of industrial development and population growth in the Klang valley has led to an estimated 77,000 t/y of waste being dumped in its major waterways. “We hope the pollution-mapping will be completed by the end of the year. With this, we can identify the most polluted areas, and stern action will be taken against the polluters under the Environmental Quality Act 2012,” the Minister stated. In addition, once the pollution areas have been identified, the relevant government authorities will be able to take action and streamline their efforts towards rehabilitating polluted waterways to their original condition.

Viet Nam plans to fuel power plant using industrial waste

In Viet Nam, the Nam Son waste treatment complex, located in Ha Noi’s Soc Son district, will initiate a project to generate power using industrial waste. The project – the first of its kind in Viet Nam – will include the construction of an incinerator to handle 75 t/d of industrial waste such as rubber, leather, cloth and plastic wastes from factories and waste from mills and mines. It will be equipped with an exhaust fume treatment system and heat recovery system connected to an electricity generator.

The US$29.2 million project has received US$22.5 million in funding from Japan through the Viet Nam Green Aid Programme. The project relies on advanced waste treatment technology and has a capacity of 75 t/d. The energy recovered will be used to generate power, with an expected capacity of 1,930 kWh, and thus help reduce greenhouse gas effects. The project will be carried out by the Ha Noi Urban Environment Co. and Hitachi Zonsen of Japan. The facility is expected to be operational by 2014, at which point the project will be expanded to other cities and provinces in Viet Nam. According to the Ha Noi Natural Resources and Environment Department, Ha Noi city discharges 750 t/d of industrial waste.


Plastics get converted into oil

A machine that converts waste plastic into crude oil – the first of its kind in North America – is operating at a recycling depot in Whitehorse, Yukon, Canada. The machine that costs about US$200,000 has come from Japan and is owned by Yukon College. The machine is installed at P&M Recycling, and can turn 10 kg of plastic into 10 L of synthetic diesel. “I do believe it can pay for itself, but I also believe it takes care of a larger problem, which is that the waste plastics are getting thrown in the garbage,” said Mr. Pat McInroy, owner of P&M Recycling. The machine will be monitored for two years and tests done on the crude oil. Mr. McInroy will use the oil to heat his plant. He says it should work in any furnace that has an inside tank. After the test period, the project will be reviewed to see if a bigger machine is required.

Process for recycling laminated films

Enval Ltd., the United Kingdom, has developed a process for recycling laminated films from packaging in which thin foil is sandwiched between layers of plastic or paper – such as food and drink packaging and tubes for toothpaste and cosmetics. Until recently, there was no technology for recovering the metal or plastic constituents. Enval aims to demonstrate that all major waste handlers, as well as processed food companies like Nestle and Kraft, could make huge savings by recovering metal and plastic components on a commercial scale rather than paying landfill taxes.

In Enval’s ‘microwave-induced pyrolysis’, microwaves provide the energy needed for heating the material. The outputs are aluminium flakes, oil and gas that is used to fire the process. According to the company, the operation will require 210-220 kW of power, all of which will be generated in the reactor on-site. Aluminium is recovered as clean metal that can be reintroduced to the supply chain. The oil can be used either as fuel for producing electricity or as feedstock for speciality chemicals. The gas powers the generator that produces electricity for the microwave system. The Alconbury plant is expected to process 1,500-2,000 t/y of material.

Total tyre recycling

With more and more vehicles on the roads, tyres call for proper disposal after their useful life. If not disposed of properly, waste tyres can pose a grave ecological risk. Pyrolysis technology, employed to recover energy from waste tyres and ensure their proper disposal, is offered by companies like Anjali Exim, Oracle Worldwide, Divya International, RD Mining Equipment and Bhagirath Equipment, based in Gujrat, India. The renewable technology takes in waste tyres as the raw material and produces fuel oil, carbon black, steel and gas.

Anjali Exim offers the technology in 5 t/d and 10 t/d packages. Waste tyres are fed into the reactor vessel of the recycling plant. In the plant, capable of executing a batch process, the tyres are heated under controlled pressure and temperature. The process brings about molecular restructuring of rubber to yield furnace oil in gaseous form, along with other gases. These vaporized gases are passed through heat exchangers, wherein the furnace oil gas is condensed into liquid form. During the process, carbon black is generated. The heat exchanger uses coolant water as the condensing medium. The water is re-circulated. The recycling plant can be operated round the clock and achieves 100 per cent waste tyre recycling. Each recycled tonne of tyre preserves 10 t of carbon dioxide (CO2), a major greenhouse gas. The company can deliver plants with capacity higher than 10 t/d.

Bioplastics from food waste and renewable raw materials

Until recently, corn, sugarcane and other edible crops were being used to make bioplastics. That sets the bioplastics industry up for competition against the world’s food supply, and several companies based in the United States are now moving away from that route. The soft drink giant Coca-Cola is making a multi-million dollar investment in bio-based companies in an effort to accelerate the development of a PlantBottle made entirely from plants. Auto manufacturer Ford is increasingly working on newer applications of bio-based plastics in its cars. Coffee company Starbucks has made its foray into the field of environment-friendly polymers with a low carbon footprint.

Globally, 1.3 billon tonnes of food is trashed, dumped in landfills or otherwise wasted every year. Research is being conducted to explore the possibility of converting food waste and scrap into polymers at low cost. Starbucks is exploring the possibility of recycling coffee grounds and other food waste to make bioplastics and other useful products. Employing food waste offers a workaround, but the challenge has been to develop a cost-effective conversion process. Ms. Carol S.K. Lin, City University of Hong Kong, China, and her team found a solution by ramping up the process with the help of enzymes from fungi. The extra enzymes help convert the carbohydrates in food waste into simple sugars. The food biorefinery process works by blending the baked goods with a mixture of fungi that excrete enzymes to break down carbohydrates in the food into simple sugars. The blend then goes into a fermenter, a vat where bacteria convert the sugars into succinic acid. The technology has other environmental benefits. Fewer pollutants enter the atmosphere because the waste is not incinerated, and the carbon dioxide (CO2) produced is reused during the biorefining process.

Bioplastics that are naturally synthesized by microbes could be made commercially viable by using waste cooking oil as a starting material. This would reduce environmental contamination and also yield high-quality plastics suitable for medical implants, according to some scientists presenting their work at the Society for General Microbiology’s Autumn Conference at University of Warwick, the United Kingdom. The polyhydroxyalkanoate (PHA) family of polyesters is synthesized by an extensive variety of bacteria as an energy source when their carbon supply is plentiful. The most commonly produced PHA polymer is poly 3-hydroxybutyrate (PHB). Currently, growing bacteria in large fermenters to produce high quantities of this bioplastic is expensive because glucose is used as a starting material. Work by a research team at University of Wolverhampton, the United Kingdom, suggests that the use of waste cooking oil as a starting material reduces production costs of the plastic. “Our bioplastic-producing bacterium, Ralstonia eutropha H16, grew much better in oil over 48 h and consequently produced three times more PHB than when it was grown in glucose,” explained Mr. Victor Irorere who carried out the research. “Electrospinning experiments, performed in collaboration with researchers from University of Birmingham [the United Kingdom] showed that nanofibres of the plastic produced from oils were also less crystalline, which means the plastic is more suited to medical applications.” The next challenge for the group is to scale up experiments to enable the manufacture of bioplastics on an industrial level.

A robust micro-organism that enables efficient production of bio-based malic acid has also been developed by Novozymes based in Denmark. The fungus enables the production of malic acid from renewable raw materials instead of oil. Malic acid is used as a flavour enhancer in the food industry and can be converted into other chemical derivatives used for a variety of plastic, polymer and resin products. Along with succinic acid and fumaric acid, malic acid belongs to the group of C4 dicarboxylic acids. C4 acids can be converted into 1.4-butanediol (BDO) that can be further converted into chemicals, including plastics, polymers and resins. The annual global market for malic acid is approximately 60,000 t and has a value of US$130 million with a growth rate of 4 per cent per year. The market for BDO and derivatives is around 1.4 million tonnes at a value of US$ 2.8 billon and with an annual growth rate of 3 per cent.

Petrochemical feedstock produced from plastic waste

At the Jawaharlal Darda Institute of Engineering and Technology, India, researchers report that plastic waste can be used as a feedstock for petrochemicals. The new process involves thermal degradation of waste plastic into fuel-range hydrocarbons (petrol, diesel and kerosene). In the thermal cracking process, waste plastic is melted and cracked in the absence of oxygen and at very high temperature. The resulting gases are cooled using condensation and crude oil recovered. Petrol, diesel, kerosene, etc. can be obtained by distilling this crude oil.

The process mainly consists of four units – reacting vessel or reaction chamber, condensation unit, receiving unit and distillation unit. More specifically, the degradation of waste plastics, except polyvinyl chloride (PVC) and polyethylene terephthalate (PET), was studied in a semi-batch reactor. Further, the effect of temperature variation on the formation of liquid hydrocarbons was also studied.

The optimum results were obtained when the temperature was maintained constant at 400°C; after this temperature, the liquid conversion decreases and the gas conversion increases. Alternative methods for disposal of waste plastic were also studied and the results have shown that the new process is better than the alternative methods used for the disposal of waste plastic. Contact: Mr. Deshpande D.P./Mr. Warfade V.V./Mr. Amaley S.H./Mr. Lokhande D.D., Department of Chemical Engineering, Jawaharlal Darda Institute of Engineering and Technology, Yavatmal District, Maharashtra, India.


Ray of light for CRT recycling

Across the world, electronics recycling programmes are collecting growing quantities of cathode ray tubes (CRTs) while the end uses for recycled CRT glass, which generally constitutes 15-30 kg per set, are disappearing. The United States Consumer Electronics Association (CEA) reports many United States recyclers having growing stockpiles of CRT glass, with no truly feasible market for it emerging to date. In a bid to find solutions to the problem, in late 2011, CEA laid down an eco-challenge to develop economic and environmentally preferable solutions for recycling CRTs. One of the eventual winners of the challenge was Nulife Glass, the United Kingdom. Nulife has developed a solution to segregate the lead in leaded CRT glass, using a highly efficient electric furnace and a combination of chemicals to produce both clean glass and lead. According to the company, the process is claimed to create neither emissions nor waste and avoid the export of hazardous material around the globe.

Mr. Simon Greer, Director of Nulife Glass and inventor of the process, explains that, using the combination of a furnace and chemistry, he managed to squeeze a tiny amount of lead out of the CRT glass and realized what the chemical formula to do it. He then set about refining the process through trial and error with the construction of several small furnaces. The first stage in Nulife’s process is to separate the panel glass from the leaded glass, which is crushed and treated with chemicals to assist the lead extraction.

The process utilizes a specially designed electrolytic converter where the CRT glass and process chemicals are melted in strictly controlled conditions to free metallic lead from glass, and is tapped off to form lead ingots. The process is continuous and has the capacity to handle 10 t/d. To increase energy efficiency, the process utilizes super-efficient insulation so that while the temperature inside the main melting unit is in excess of 1,000°C, the outside never exceeds 60°C. In addition to being energy efficient, the converter has negligible emissions, eliminating the need for expensive extraction and filtration systems. The process uses around US$0.50 worth of electricity for each CRT treated and recovers around US$2 worth of lead as well as clean glass.

New e-waste tracking system developed

In the United States, InnoCentive, a crowd-sourced problem-solving company that offers prizes for solutions, the non-profit advocacy group Environmental Defense Fund and data storage company EMC Corp. have announced the conclusion of a challenge aimed at finding a way to better track shipments of used electronic goods. The challenge was issued to find a scalable way to track e-scrap to its final destination in the hope of adopting more environmentally sustainable ways of managing the material. Participants in the challenge were asked to help develop a process or device that would allow electronics manufacturers to follow what happens to their products as they make their way through the waste stream. The three winning solutions selected from more than 60 solutions submitted are:
  • A unique 12-digit code printed directly onto each sub-system component using passive radio frequency identification ink;
  • An electronic tag that combines identification codes printed on components with a crowd-sourcing on-line platform that together yield a holistic picture of where electronic components end up; and
  • A tracking system that leverages a label sheet printed with unique, encrypted codes for each key component in the system. The labels would be applied to and follow subsystem components, as they move through the disposal process.

Fujitsu turns recycled CDs into notebook computer parts

High-tech giant Fujitsu, Japan, has developed an industry first: a technology that recycles plastic from used CDs and DVDs into notebook computer components. Fujitsu’s system not only processes recycled plastics but also flags all toxic chemical contaminants in the materials that are listed in the company’s risk management database. The process can use about 10 t/y of virgin plastic in Fujitsu’s products and cut carbon dioxide emissions associated with manufacturing by about 15 per cent annually. Raw materials for the process are supplied by Fujitsu’s five recycling centres in Japan, where the company collects, disassembles, sorts and recycles personal computers as well as other consumer electronics gadgets.

Because it is difficult to get a uniform mixture from the wide assortment of plastics collected, Fujitsu decided to focus on CDs and DVDs, which are often included with PCs and are readily available in predictable quantities. These optical discs are made of polycarbonate, a type of plastic suitable for making bodies of notebook computers. Moreover, as they do not have any contaminants such as flame retardants, they were deemed to be a suitable material for recycling. The first system to include the recycled plastic is the Fujitsu Lifebook P772/E notebook computer. The front panel of the device is made from recycled plastic. Fujitsu plans to expand the recycling process to other notebook computers and products.

E-waste processing in a counter-current teeter-bed separator

At the National Metallurgical Laboratory (NML) of the Council of Scientific and Industrial Research (CSIR), India, scientists have researched advanced gravity separation of ground e-waste in a teeter-bed separator. The research established that the Floatex Density Separator (FDS) is a promising device for wet processing of e-waste to recover physically valuable metals. The metal content in the feed was enriched from 23 per cent to 37 per cent in the product in a single-stage operation using FDS, with over 95 per cent recovery of the metals. A two-stage processing scheme was developed that enriched the metal content further to 48.2 per cent. The influence of the operating variables, namely, teeter water flow rate, bed pressure and feed rate were quantified. Low bed pressures and low teeter water rates produced higher mass yields with poorer product grades. On the contrary, a high bed pressure and high teeter water rate combination led to a lower mass yield but better product quality. A high feed rate introduced en masse settling leading to higher yield but at a poorer product grade. Contact: Mr. Sujit Kumar Dey/Mr. Vidyadhar Ari/Mr. Avimanyu Das, CSIR-NML, Burma Mines, Jamshedpur, Jharkhand 831007, India.

New method to recycle e-waste developed

In India, scientists at the Institute of Chemical Technology (ICT) and the Bhabha Atomic Research Centre (BARC) have jointly developed an eco-friendly method to recycle used printed circuit boards (PCBs) from personal computers without releasing toxic gases into the environment. The three-member team used high-energy electron beams to degrade a PCB and prepare it for recycling.

At present, e-waste such as PCBs that contain hazardous chemicals are disposed of by open burning by the informal sector. “We decided to work on e-waste components that are found in large quantities and where recycling poses an environmental challenge. Every household has a computer that is eventually discarded,” said Prof. R.N. Jagtap, Head, Department of Polymer and Surface Engineering at ICT and part of the study. “Our method does not release effluents or toxic gases in the air.”

E-waste separator

Henan Province Sanxing Machinery Co. Ltd., China, offers equipment for recycling scrap electronic components. Based on advanced recycling technologies, crushers and high-voltage electrostatic separators are employed for mechanical pulverization and recovery of useful components from waste printed circuit boards (PCBs) from computers and television sets, aluminium-plastic panels, copper-coated plates and used electric appliances. The equipment ensures metal recovery of 98 per cent purity. Contact: Mr. Zhang Yunlong, Manager, Henan Province Sanxing Machinery Co. Ltd., West Gang, Xushui Town, Zhongyuan Region, Zhengzhou, Henan, China. Tel: +86 (371) 6784 2763; Fax: +86 (371) 6784 2730; Website:


Affordable, world-class medical waste disposal system

A team led by Mr. Ricky Dayot at Rad Green Solutions in the Philippines has reported a low-cost and environmentally safe medical waste management system named as the Pyroclave. The Pyroclave is a medical waste processor that uses pyrolysis, the process of decomposing organic material using extreme heat in the absence of oxygen. Unlike incineration or burning, pyrolysis produces fewer by-products. The process effectively carbonizes all solid material and produces 50 per cent less carbon dioxide.

Pyrolysis has been touted as a viable option for medical waste management, but the cost has so far been prohibitive. With the Pyroclave, the waste material is placed inside a sealed rotating chamber. Once the machine is turned on, it goes to work and starts heating the rotating chamber. The intense heat within the chamber (up to 1,200°C) starts carbonizing the medical waste. The synthetic gas (syngas) produced by the intense heat and decomposition process is recycled and fed into the burners, thereby serving as an added fuel to continue the process and help boost combustion. After 15-45 minutes (depending on the type of material and its quantity), what is left behind is the carbonized, soil-like remnants of the medical waste that the inventors claim is safe enough to be disposed of anywhere and can even be used as soil conditioner.

The Pyroclave has several unique features. A crucial cost-saving element is the device’s patented Hydroburn technology – invented by Mr. Rodolfo Dayot, Chief Scientist at Rad Green – that enables the Pyroclave to generate more heat with less fuel. The Pyroclave is cheaper than incineration and autoclaving. In addition to being a medical waste processing system, the Pyroclave can also be used to sterilize or disinfect medical equipment simply by changing the settings of its computerized control panel. Facilities that house the Pyroclave also have nothing to fear as the technology is safe and the numerous safety features installed (pressure release valves, emergency stop, temperature and pressure switches, temperature controls) will automatically turn off the device in case something go wrong. Pyroclave is capable of processing 500 kg of medical waste per day at a cost of US$0.49-0.61.

One-stop-shop waste treatment solution

At its site in Antwerp, the Netherlands, Indaver has installed MediPower® – a risk-free solution for disposing medical and sensitive waste from hospitals, medical laboratories and healthcare sector. The expertise and experience of specialist personnel safeguard the processing of this hazardous waste. Locating MediPower at the Antwerp site allowed Indaver to provide customers a one-stop-shop solution, with on-site back-up. There is no unnecessary handling and the follow-up treatment is also carried out at the same site. All these eliminate any risk of contamination from the handling or reuse of packaging.

Once MediPower starts to run at full power, it will process 30,000 t/y of medical and other hazardous and sensitive waste. Indaver plans to provide the healthcare and medical sector with a high-grade alternative without any handling risks. Because medical waste is hazardous, combustion proceeds at a very high temperature to ensure that all harmful components are fully destroyed. An electro-filter, gas scrubber and dioxin filter dedust and clean the flue gases thoroughly, so that the emissions comply with the strict norms. The heat released from the combustion process is recovered in the form of steam and electricity. The steam is used as process steam and for heating the site’s own buildings and neighbouring businesses. The electricity is used for on-site installations or supplied to the grid. Contact: Mr. Rob Kruitwagen, Regional Manager, Indaver nv, Dijle 17 a, BE-2800 Mechelen, Belgium. Tel: + 32 (15) 288000; Fax: + 32 (15) 288050; E-mail:

Mobile medical waste treatment system

Chongqing Gient Heating Industry Co. Ltd., China, offers a vehicle-mounted system for steam-based treatment of medical and healthcare waste. The waste materials to be treated are placed into an autoclave with dedicated bins, pre-vacuum controlled by programmable logic controller (PLC), and are then steam sterilized for complete disinfection. The technical scheme is characterized by a high degree of integration of treatment operations, with minimum of space taken to complete all functions. The whole process can be completed by two operators, and its mobility means that the system could be used for:
  • Supplementary and emergency back-up;
  • Supporting medical aid units in epidemic or disaster areas;
  • On-site treatment and disposal of medical waste in isolation hospitals;
  • Medical waste treatment in marginal areas not covered by medical waste treatment system; and
  • Safe disposal of carcasses of domestic animals carrying disease germs.

Contact: Chongqing Gient Heating Industry Co. Ltd., No. 3, East Road, Gaobaohu, Konggang Industry Zone, Yubei District, Chongqing, China 401120. Tel: +86 (23) 6181 3706; Fax: +86 (23) 6181 3768.

Plasma-based on-site waste treatment

PEAT International Inc., the United States-based plasma-based waste remediation solutions provider, has successfully commissioned its first plasma thermal destruction and recovery-100 (PTDR-100) system at the Gujarat Industrial Development Corp., India. The 60 kg/h PTDR-100 system was developed to primarily treat biomedical waste and other industrial/universal waste streams. The PTDR-100 represents a first-of-its-kind system – a permanent, fully self-contained platform for hospitals and industrial facilities. Based on proprietary technology, the environmentally clean PTDR process uses plasma torches to convert waste into a synthetic gas comprising mainly carbon monoxide and hydrogen, a valuable alternative energy source that can be used for electricity and/or hot water generation and other useful end products.

The PTDR-100 system is equipped with a 100 kW plasma heating system. The entire system can be operated by one person via a control panel. There is no secondary pollution; just usable end products are generated, totally eliminating the need for landfill disposal and/or further processing. Wastes processed in a PTDR-100 system typically see high volume (more than 200:1) and weight (more than 10:1) reductions, together with a high destruction and removal efficiency of organic materials (more than 99.9999 per cent). PEAT has successfully processed a combination of waste streams (co-mingled and individual), including biomedical wastes, dye intermediates, pharma industry wastes, distillation bottoms and municipal wastes over a period to commission, validate the system through tests and collect operational data for obtaining all future regulatory approvals. Contact: Mr. Daniel Ripes, Chairman, PEAT International Inc., 555 Skokie Boulevard, Northbrook, IL 60062, United States of America. Tel: +1 (847) 559 8567; Fax: +1 (847) 291 3704; E-mail:; Website:

Viet Nam’s first hi-tech incinerator for medical waste

In Viet Nam, Hoa Tu Long Industry Co. has officially put the medical waste incinerator YT30 into operation. This is reportedly the first high-tech incinerator made in Viet Nam. The incinerator has the capacity to process 30-50 kg/h of medical and healthcare waste. The YT30 incinerator is a custom-made continuous incinerator; that is, when the incinerator is in operation one can still open the incinerator’s door to put in more things. A big advantage of the incinerator manufactured with Vietnamese technology is that after burning, only glass and aluminium dioxide are left; all other substances would be burned off, including needles. In addition, the incineration speed is four times faster than other competing incinerators with the same capacity.

The combustion chamber has two furnaces: primary and secondary. Medical waste is put into the primary furnace first. Once the waste starts burning, the smoke is directed to the secondary furnace for further burning. After that, the smoke is passed through to a dust handling system using nanotechnology, and then through a water tank before discharge into the environment.

According to Mr. Trinh Dinh Nang, the incineration cost of 1 kg of medical waste is very low (at US$0.25, if using diesel, and US$0.10 only if using waste oil) – about 10 to14 times cheaper than other comparable foreign incinerators available on the market. In addition, the cost of the Vietnamese system is 40-50 per cent cheaper than that of foreign incinerators. The YT30 incinerator is easy to repair and is expected to have a long life expectancy.


Turning wastewater into fertilizer

Researchers at the Fraunhofer Institute for Interfacial Engineering and Biotechnology (IGB), Germany, have developed an efficient and environmentally friendly process to recover phosphate from wastewater for use in fertilizer production. The electrochemical process, currently being tested in a mobile pilot plant, could contribute towards a sustainable future for agricultural us of phosphorus, which is becoming increasingly scarce and expensive due to high global demand. Some methods already exist to recover phosphorus from wastewater in the form of a salt – a magnesium-ammonium phosphate called struvite. However, these methods require the addition of a base to raise the pH and magnesium-based chemicals as precipitating agents, thus increasing costs.

The IGB process obtains struvite from wastewater without the need to add any chemicals. Instead, the required magnesium (Mg) is added via an Mg electrode, which is highly reactive and therefore requires very little energy. The pilot system has a 2 m high electrolytic cell through which wastewater is directed. With a sacrificial Mg anode and a metallic cathode, the electrolytic process splits water molecules into negatively charged hydroxyl ions at the cathode. At the anode, the Mg ions migrate through water and react with phosphate and ammonium molecules in the solution to form struvite. The advantage of this process is that the struvite thus obtained can be used as fertilizer without further processing.

Efficient wastewater treatment system

High-performance, environmentally friendly gas injection systems from Linde North America, based in the United States, now facilitates more efficient control of pH, biological oxygen demand (BOD), dissolved organics and odours at water and wastewater treatment plants. Linde offers oxygen (O2), ozone (O3) and carbon dioxide (CO2) gas dissolution systems that can significantly improve treatment process efficiencies while helping customers meet environmental requirements – often at a lower cost than existing treatment methods. Linde’s water treatment technology has application in many industries including dairy and beverage, meat and poultry, pulp and paper, textiles and dyeworks, as well as prepared foods, laundry, cement, desalination and chemical processing.

To decrease BOD, dissolved organics and odours, Linde offers the SOLVOX® process, an effective supplement or replacement to forced air systems. As air is only 21 per cent oxygen, the SOLVOX oxygenation process can be almost five times more efficient. Oxygen use can also save energy required for compressors in high-volume aeration systems. The SOLVOCARB® process is a rapid and economical way to neutralize alkaline wastewater with a high degree of control using CO2. When dissolved in water, CO2 forms carbonic acid to quickly reduce pH to appropriate levels for discharge. CO2 is an inert gas and mild buffering agent, thus providing a much safer alternative to hazardous and corrosive mineral acid treatments, such as with sulphuric acid. CO2 is also important for reverse osmosis as well as remineralization systems.

Nano adsorbent for dye removal from wastewater

Researchers at the Chemistry Department of Islamic Azad University, the Islamic Republic of Iran, have reported the development of dye-adsorbing nanocomposites based on wood waste and residue, with potential use in the treatment of effluents discharged from textile and dye industries. “Our research works have been mainly focused on developing inexpensive and efficient nanoadsorbents. In this regard, we concluded sawdust as an excellent basis and applied the chemical co-precipitation method to synthesize nanocomposites of CuFe2O4/sawdust (with copper and iron oxides and nanoferrite spinel as the raw materials),” said Dr. Saeedeh Hashemian, member of the academic board of Islamic Azad University, Yazd Branch.

The researchers subsequently evaluated the efficiency improvements that have resulted because of the incorporation of sawdust in the prepared nanocomposite, to facilitate adsorptive removal of cyanine acid blue (CAB) – a hazardous chemical – from aqueous solutions. The results obtained establish that nanoferrite spinel particles have been deposited favourably on the sawdust structures. Furthermore, the yielded nanocomposite was shown to possess a higher dye-removal efficiency when compared with that of each of its components (i.e. sawdust and ferrite spinel) applied singly, Dr. Hashemian reported.


Bioremediation to alleviate surface water pollution

Often, ground and surface waters are characterized as separate resources although they are interrelated. Surface water seeps through the soil and becomes groundwater. Conversely, groundwater can feed surface water sources. A European Union research project “Sediment biobarriers for chlorinated aliphatic hydrocarbons in groundwater reaching surface water” (Sedbarcah) has investigated the possibility of using naturally occurring microbes to bio-decontaminate groundwater.

The Sedbarcah project is investigating the possibility that the sediment between surface water and groundwater may act as a supply of both physico-chemical and biological degradation agents. Particularly, scientists focused on the biological source, a natural biobarrier. The project, by harnessing the action of anaerobic microbes present in sediments because of eutrophication, aimed to put the bacteria to good use. To do this, the scientists determined the role and genetic make-up of the microbial community living in the river bed by monitoring activity in sediments of the River Zenna in Belgium and the Belá river in the Czech Republic. The project team focused specifically on the pollutant group called chlorinated aliphatic hydrocarbons (CAHs). In anaerobic conditions, CAHs can be completely oxidized to carbon dioxide, water and chlorine by the microbes. The project focused specifically on dechlorinating bacteria.

The subsequent step was to augment the pollutant removal activities of the microbes and sustain these processes, as well as develop tools to research microbial degradation in situ. To increase the bioremediation potential of the microbial community, scientists investigated the effects of changing variables like nutrients and electron donors and receptors. Sedbarcah project has collected valuable data for bioremediation systems to decontaminate surface water systems.

Bioremediation of toxic metals using worms

Researchers at the Department of Ecology and Environmental Sciences, Pondicherry University, India, report that three species of earthworms – Eudrilus eugeniae, Eisenia fetida and Perionyx excavates – can be used to assist in the composting of urban waste and to extract heavy metals (including cadmium, copper, lead, manganese and zinc) prior to subsequent processing. According to the research team, the process of vermicomposting using earthworms allows organic waste materials to be remediated and the compost then utilized for growing food without the risk of accumulation of heavy metals in the crops.

According to the team, the worms can remove up to three-quarters of the various heavy metals from solid waste. The E. eugeniae species was found to be the most effective at remediating solid waste and producing rich compost. The team’s tests revealed that vermicomposting can reduce the heavy metal content in organic wastes to levels significantly below the permissible safe limits. The digestive system of the worms is capable of detaching heavy metal ions from the complex aggregates between these ions and humic substances in the waste as the waste rots. Various enzyme-driven processes then lead to assimilation of the metal ions by the worms so that they are locked up in the worms’ tissues rather than being released back into the compost as worm casts. The separation of dead worms from compost is a relatively straightforward process allowing heavy metal to be removed from the organic waste.

How microbes can help the planet and create energy

Scientists at the Masdar Institute, United Arab Emirates (UAE), are delving into the potentially profitable science of using microbes to provide renewable and sustainable energy as well as help remove contaminants from the environment. Using high-throughput sequencing – in which many pieces of DNA or RNA are read at the same time, allowing for very fast results – researchers are exploring a range of issues – from removing contaminants from the environment to using microbes to produce energy-rich molecules such as methane or hydrogen. One project, led by Dr. Farrukh Ahmad, is exploring ways in which environmental microbes can help remove chemicals from environmental water bodies, making water safer for use. Dr. Ahmad’s team is isolating micro-organisms that can degrade industrial compounds. High-throughput sequencing is utilized to identify the chemical pathways involved and to develop processes that can help with decontamination.

Another research group, led by Dr. Lina Yousef, is taking a look at the messenger RNA – the molecules that provide information for chemical pathways – from actively transcribed genes. The team hopes to gain an understanding of both how microbes evolved to adapt to UAE’s extreme environments and how the evolution of biochemical pathways can be directed for the purposes of bioremediation and energy production. Another colleague, Dr. Jorge Rodriguez, is developing mathematical models describing how micro-organisms could be employed in the regeneration of wastewater and in producing biofuels from the organic waste in wastewater. Dr. Rodriguez and his team is studying the metabolic profile of a reed bed microbial ecosystem that removes contaminants from wastewater. A second project looks at the production of methane or hydrogen from wastewater through anaerobic fermentation. Bringing computing to bear on the issue, Dr. Andreas Henschel is developing algorithms to identify and extract new metabolic pathways from large genomic databases.

Using microbes to clean up pollution

Microbes such as fungi and bacteria are nature’s best and longest-serving scavengers, and Coenbio Co., the Republic of Korea, says that with a little help they will be the best for remediating human-made waste dumps. “What we need to do is to put the right microbes on the right assignment and create an environment where they can best perform,” stated Mr. Yum Kyu-jin, CEO and founder of the company.

“In a controlled lab environment, a microbial agent may work just as anticipated, breaking down the contaminants and eating them away. But in reality, there are so many variables and factors that affect the process,” Mr. Yum stated. In the domestic market, Mr. Yum’s tiny venture has proved several times that it can deliver low-cost, low-impact and energy-efficient solutions by using micro-organisms. “The microbial agents that we inject into the target site are like an amphibious landing unit that opens the way for the main force to do the real war,” Mr. Yum said. Coenbio’s pollution-loving microbes gobble up the main pollutants – heavy metal, oil, toxic chemicals and the like – and nature restores itself. Coenbio holds more than 300 micro-organism strains and scores of domestic and international patents on them.

Plants, earthworms and organic matter to repair polluted soil

At the Institute of Ecosystem Study (ISE), Italy, researchers are studying bioremediation of polluted soil through a combination of plants, earthworms and organic matter. Two plant species (Cytisus scoparius and Paulownia tomentosa), earthworm (Eisenia fetida) and organic matter (horse manure) were used as an ecological approach to bioremediate soils contaminated with heavy metals and hydrocarbons. The experiment was carried out for 6 months at a mesoscale level using pots containing 90 kg of polluted soil. Three different treatments were performed for each plant: untreated planted soil as a control; planted soil + horse manure (20:1 w/w); and planted soil + horse manure + 15 earthworms.

While both the plant species were able to grow in the polluted soil and improve the soil’s biochemical conditions, few significant differences were noted. C. scoparius improved soil nutrient content more than P. tomentosa, which instead stimulated more soil microbial metabolism. P. tomentosa was more efficient in reducing the heavy metal (Pb, Cr, Cd, Zn, Cu, Ni) content, while earthworms particularly stimulated the processes involved in the decontamination of organic pollutants. This ecological approach, validated at a mesoscale level, has recently been transferred to a real scale situation to carry out the bioremediation of polluted soil in San Giuliano Terme Municipality. Contact: Institute of Ecosystem Study (ISE), CNR, Via Moruzzi, 1, Pisa, Italy.

Bioremediation of Cd-DDT contaminated soil

In China, researchers at Zhejiang University and Hainan University are investigating bioremediation of soil co-contaminated by cadmium (Cd) and dichlorodiphenyltrichloroethane (DDT), using an identified Cd-hyperaccumulator plant Sedum alfredii and DDT-degrading microbes (DDT-1). The study aims to develop a bioremediation strategy for fields co-contaminated with Cd, DDT and its metabolites – 1, 1-dichloro-2, 2-bis (4-chlorophenyl) ethylene (DDE) and 1, 1-dichloro-2, 2-bis (4-chlorophenyl) ethane (DDD) – using S. alfredii and DDT-1. Initially, inoculation with DDT-1 was shown to increase S. alfredii root biomass in a pot experiment. S. alfredii and DDT-1 together reduced the levels of Cd and DDTs in the contaminated soil by 32.1-40.3 per cent and 33.9-37.6 per cent, respectively, in a pot experiment over 18 months compared with 3.25 per cent and 3.76 per cent decreases in soil Cd and DDTs, respectively, in unplanted and untreated controls. A subsequent field study (18-month duration) has confirmed the beneficial results of this approach. The study showed that the integrated bioremediation strategy is effective for remediation of Cd-DDTs co-contaminated soils. Contact: Ministry of Environment’s Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Zijingang Campus, Hangzhou 310058, China.


Regenerative thermal oxidizers include pre-filtration systems

Adwest Technologies Inc. from the United States offers regenerative thermal oxidizers (RTOs) with pre-filtration systems. Provided in skid-mounted, pre-piped and wired modules, the flameless RETOX RTOs have flow rates of 1,000-80,000 cfm and are suited for particulate- and dust-laden volatile organic compound (VOC) processing. The units provide 99 per cent VOC abatement with corrosion-resistant, ceramic, dual-chamber heat exchanger rated up to 97 per cent effective for primary heat recovery. Flameless natural gas injection operation does not generate any nitrous oxide (NOx) by-products during VOC combustion and oxidation processes. The cost-effective VOC control solution is supplied with pre-filtration systems for pharmaceutical, chemical, paint, pulp and paper, biopharma, oil and gas, hydrocarbon, composites, food and many other sectors.

Pre-filters are specifically selected for each RTO application to minimize any particulate build-up prior to the oxidizer system. Adwest’s unique flameless NOx-free RETOX RTO natural gas injection (NGI) operation provides 40-65 per cent less natural gas usage compared with conventional burner and combustion air blower thermal oxidizer operation. The RETOX RTO’s ultra-low energy usage helps avoid the need for periodic carbon or catalyst replacement and maintenance, further lowering the life cycle total cost of RTO oxidizer abatement. Contact: Mr. Brian Cannon, Vice President, Sales and Marketing, Adwest Technologies Inc., 1175 N. Van Horne Way, Anaheim, CA 92806, United States of America. Tel: +1 (585) 5931 405; Fax: +1 (585) 5936 614; Website:

New carbon dioxide capture technology

In the Republic of Korea, scientists have developed a new carbon dioxide (CO2) capture technology that is reported to be the most energy-efficient among currently available methods. Carbon capture involves removing CO2 from industrial waste gases released into the atmosphere to lower the industry’s impact on the environment. The team led by Mr. Yoon Yeo-il of the Korea Institute of Energy Research uses potassium carbonate to extract CO2 combustion gas released at industrial plants. The technology known as KIERSOL can be used to extract CO2 gases released from industrial facilities that range from power stations to steel and cement plants, wherein the CO2 content of exhaust gases varies from 10 to about 25 per cent, according to the Ministry of Education, Science and Technology.

The KIERSOL technology uses 20 per cent less energy in recycling the solvent, making it one of the most energy-efficient methods of carbon capture available. In carbon capture facilities, the exhaust gas is exposed to the CO2-absorbing materials before it enters the atmosphere. The solvent is then heated to remove the CO2, allowing it to be reused in the carbon capture process. In addition, the KIERSOL process is less sensitive to sulphur and halogen compounds found in combustion gases than conventional CO2-capturing materials. Other solvents’ higher reactivity with sulphur and halogen compounds means the CO2-absorbing material needs to be replenished more often. By optimizing the KIERSOL technology for extracting CO2 from waste gas produced from combusting natural gas, the Korea Institute of Energy Research has also developed KIERSOL-N.

New ways to reduce emissions and save money

In the United States, the West Virginia plant of American Bituminous Power Partners recently installed an advanced process control package – Meso Corporation’s DNA system – to help improve performance and reduce production costs. This has resulted in a 7 per cent reduction in limestone usage over the operating range. Improved sulphur dioxide (SO2) capture efficiency has eliminated the need for a post-combustion flue gas treatment system, thereby saving costs. Each of the circulating fluidized bed boilers at the power plant has a maximum rating of 400 kpph of superheated steam, with coal refuse as the primary fuel.

The study phase included a physical examination of the boiler and its auxiliaries, control system tuning parameters and benchmarking of the two boilers. Metso’s DNA system took over control of bed inventory, oxygen control, combustion profile optimization and air/fuel master controls. The system has also helped stabilize furnace wall temperatures, to extend the life of the boiler and reduce thermal stress.

Engine exhaust NOx control without using oxidation

GM Global Technology Operations Inc., the United States, reports a method for engine exhaust nitrogen oxide (NOx) control using no oxidation in the engine. The method for reducing NOx emission in the power train – comprising an internal combustion engine with a combustion chamber and a post-treatment system – includes monitoring an actual exhaust gas feed stream ratio of nitrogen dioxide (NO2) to nitric oxide (NO), monitoring a desired exhaust gas feed stream NO2:NO ratio, comparing the actual and the desired exhaust gas feed stream NO2:NO ratios and selectively initiating an NO2 generation cycle based on the comparison of the actual and the desired exhaust gas feed stream NO2:NO ratios. The last-mentioned action comprises injection of fuel mass into the combustion chamber after a primary combustion event.

Alternative process for FGD scrubbing

Veolia Water Solutions & Technologies, the United States, offers an alternative thermal process for flue-gas desulphurization (FGD) scrubber blowdown. Environmental regulations that are looming may have the practical effect of requiring zero liquid discharge (ZLD) wastewater treatment for power plants that use wet limestone scrubbers. In ZLD processes, industrial wastewater is reduced to a solid that is usually disposed of in landfill. Water recovered from the process is recycled and reused in the plant.

Conventional ZLD evaporation crystallization processes for evaporation-FGD scrubber blowdown waste streams have numerous drawbacks and shortcomings. These processes require clarification and extensive pre-treatment of the wastewater with lime, soda ash and other chemicals to replace the calcium, magnesium and heavy metal ions in the wastewater with sodium ions in order to produce a solid for landfill disposal. The equipment and chemicals involved in this pre-treatment increase the footprint of the ZLD system as well as the capital costs and overall maintenance of the wastewater treatment plant.

Veolia’s CoLD™ Process provides an economical and efficient treatment system. Using proven evaporation and crystallization technology, the CoLD™ process yields clean water and stable solids to achieve zero liquid discharge on difficult FGD purges. The benefits of the process include:

  • Achieves zero liquid discharge on difficult coal-fired wastewaters;
  • Lowest capital expense as well as operational costs;
  • No chemical pre-treatment or sludge production;
  • Produces clean water for reuse and stable solids for disposal; and
  • Simple, robust process with high reliability.

Contact: Veolia Water Solutions & Technologies Inc., 23563 W. Main Street, IL Route 126, Plainfield, IL 60544, United States of America. Tel: (815) 609 2000; Fax: +1 (815) 609 2044; E-mail:

New clues for capturing CO2

Metal-doped materials can remove carbon dioxide (CO2) directly from air. A sprinkling of zirconium (Zr) helps a CO2 scrubber material capture up to four times as much CO2, researchers say. Zr also makes the material more resilient to repeated use. Solid materials that can grab CO2 directly from air could potentially generate CO2 for use in chemical and polymer production or for underground sequestration.

So far, the search has focused on varying the design of amines encased in porous silica. Modifying slightly the standard methods for creating the carbon-scrubbing materials, Mr. Christopher W. Jones from Georgia Institute of Technology, the United States, and his colleagues mixed various metals into silica and then added polyethylenimine. They tested how well the scrubber materials worked by weighing them in a flowing gas, either 10 per cent CO2 in argon to simulate the flue gas from a power plant or 400 ppm CO2 in argon to simulate ambient air. The materials that picked up the most weight, the researchers reasoned, had adsorbed the most CO2.

After screening titanium, cerium and aluminium, the team saw efficiency increase dramatically with Zr – 7 per cent Zr worked best. At higher percentages, the structure of the silicate degraded, lowering the efficiency of the scrubber. Compared with undoped silica, the 7 per cent Zr material adsorbed twice as much CO2 from the flue gas set-up and four times as much when the CO2 was diluted to 400 ppm. The team stripped the CO2 from the scrubber material by heating it in argon flow, readying it for reuse. The material’s capacity for CO2 adsorption reduced only slightly after four uses. Mr. Chunshan Song, a chemical engineer at Pennsylvania State University, the United States, has ratified the results with what his group saw when doping silica with aluminium to use as the amines’ support.


Wastewater Treatment: Advanced Processes and Technologies

This guidebook presents important concepts, technologies and issues, essentially distilling the information into actionable treatment methods for various types of pollutants. The book, edited by experts in the field, explores recent advances in wastewater treatment by various technologies such as chemical methods, biochemical methods, membrane separation techniques and by the application of Fenton and solar photo Fenton methods. It explores new technologies that produce clean water and energy from the wastewater treatment process, and addresses sustainable water reclamation, biomembrane treatment processes and advanced oxidation processes for wastewater treatment.

Contact: Customer Service CRC Press, United Kingdom. Tel: +44 (1235) 400524; Fax: +44 (1235) 400525; E-mail: book.

Solid Waste Management: Principles and Practice

Solid waste problems and approaches to tackling them vary from country to country. For example, while efforts are made to collect and dispose hospital waste through separate mechanisms in India, it is burnt together with municipal solid waste in Sweden. While trans-boundary movement of waste has been addressed in numerous international agreements, waste from other nations continues to reach developing countries in many forms. While thousands of people depend on waste for their livelihood throughout the world, many others face problems because of poor waste management. In this context, solid waste has not remained an issue to be tackled by the local urban bodies alone. It has become a subject of importance for engineers as well as doctors, psychologist, economists, climate scientists and any others. There are huge changes happening in waste management in different parts of the world. The authors of this book combine their vast experience and bring together a detailed look at the theory and practice of solid waste management, also covering the important relevant literature.

Contact: Springer (India) Pvt. Ltd., 3rd Floor, Gandharva Mahavidyalaya, 212, Deen Dayal Upadhyaya Marg, New Delhi 110 002, India. Tel: +91 (11) 4575 5888; Fax: +91 (11) 4575 5889; E-mail:


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