October 2012, Vol. 24, No.10

Research Notes

Project seeks to produce energy and treat wastewater in extreme climate

Mongolia’s mining activities have led to economic growth, resulting in increased urban and suburban populations and a lack of adequate sanitation.  

Wastewater infrastructure also has to address the problems of increasing water scarcity and deforestation . Mongolia’s climate, which consists of long winters with low temperatures reaching –40°C and extended hot, dry periods with sandstorms, poses significant challenges for water and wastewater infrastructure, according to a Helmholtz Centre for Environmental Research (UFZ; Leipzig, Germany ) news release .  

To avoid freezing, infrastructure pipes have to be buried between 3.5 and 4.5 m below ground. Biological wastewater treatment requires heating or additional housing, leading to greater costs, which often are unaffordable in Mongolia, the news release says. All these conditions, combined with old and unreliable infrastructure, are a challenge for developing appropriate wastewater treatment technologies, the news release says.  

Therefore, UFZ, in cooperation with Mongolian and German partners, initiated the Integrated Water Resource Management in Central Asia: Model region Mongolia (MoMo) project. The project identifies water management solutions for Mongolia that would address the problems described above and provide an integrated water resources management concept for decentralized wastewater treatment, the news release says.  

For the project, researchers commissioned a decentralized wastewater pilot plant with integrated wood production. The plant is a component of the second phase of the project to develop an integrated management plan for the Kharaa basin, the news release says. 

The basin is located in north Mongolia and incorporates the city of Darkhan, with a low annual precipitation rate of 280 mm. The area faces increased deforestation from logging and grazing pressure, leading to the loss of ecological services in the Kharaa River floodplain, the news release says. 

The research group’s proposed solution is to pretreat wastewater for irrigating and producing willow trees onsite. The trees provide an integral part of the treatment process while also providing an important resource. The research program focuses on water quality requirements for sustainable irrigation and considers responses to the climatic conditions, such as the storage of irrigation water and operation of the plant during winter. Research results will help optimize the system and identify its feasibility for implementation as integrated water resource management on a wider, regional scale, the news release says.  

The project is funded by the German Ministry of Education and Research, and Phase 2 of the project involves researchers, private organizations, and ministerial departments from Mongolia and Germany.  


 

Study expands activated sludge model

Organic nitrogen removal is variable, and reverse osmosis may not consistently produce total nitrogen levels less than 1.0 mg/L, according to a new report by researchers from Brown and Caldwell (Walnut Creek, Calif.) and the City of Escondido, Calif.  

The researchers conducted a pilot study to determine total nitrogen removal by reverse-osmosis processes. They compared organic nitrogen removal rates with removals observed from three full-scale reverse-osmosis facilities and four pilot studies, according to an article in the July issue of Water Environment Research .  

“The nature and concentration of organic nitrogen in secondary effluent will vary depending on the wastewater,” the article says. “Therefore, it is not possible to know the actual organic nitrogen concentration in reverse osmosis effluent without testing.”  

Organic nitrogen in secondary effluent can have low molecular weights and exist as uncharged species that may not be removed through reverse osmosis. Its measurement at low levels may not be accurate using traditional methods, so alternative measurement methods may be needed, the article says.  

Identifying organic nitrogen concentrations is crucial for municipalities attempting to achieve low total nitrogen levels and evaluating related processes, the article says. Using upstream biological nutrient removal to target inorganic nitrogen, coupled with a physical/chemical process, such as coagulation or activated carbon, to target organic nitrogen, could be a potential solution. 

The article, “Analysis of Organic Nitrogen Removal in Municipal Wastewater by Reverse Osmosis,” appears in the July issue of Water Environment Research and can be downloaded free at http://goo.gl/cm7lY. 

 

Water Environment Research allows open access to one article per issue on a range of important technical issues such as nutrient removal, stormwater, and biosolids recycling. 

 


 

More food for less water requires more research, experts say

As global populations and incomes grow, available land and freshwater supplies decrease. U.S. food and agricultural experts released a paper examining livestock, land, and water issues raised by the U.N. Food and Agriculture Organization (FAO).  

In 2006, FAO identified the major challenge of doubling global production of livestock products without increasing environmental damage, according to a Council for Agricultural Science and Technology (Ames, Iowa) news release. 

The paper describes how the relationships among livestock, land, and water resources are affected directly by productivity improvements from technological advances, waste management system improvements, increased understanding of pollution processes, and emerging demands on livestock production systems to address social goals, the news release says.   

A 30% increase in global population, estimated to occur by 2050, will result in a 70% increased demand for food, the paper’s summary says. A demand for exports and biofuels will compete for local agricultural production, and the demand for resources, such as land, water, minerals, and energy, will continue to grow. In arid regions, as water demands increase, so do the pressure on and abandonment of agricultural areas. And the potential for climate changes to decrease rainfall poses additional water resource challenges, the summary says.  

Two related concepts have emerged to optimize systems and minimize effects on resources, the environment, and health: the life-cycle approach, which enables analysis and management of livestock production, and systems analysis, which aids in understanding interactions within livestock production systems, the summary says.  

“The protection of farmland and the capacity to sustain food production and the provision of ecological and aesthetic services is a policy issue of growing importance,” the summary says. Investment in research to understand and optimize agricultural production systems has been critical to devising efficient policy and minimizing negative effects.  

A new commitment is needed to increase agricultural productivity, decrease environmental effects, and use available resources more efficiently during the next 40 years, according to the summary. “Policy to create that productivity growth in both plant and animal systems and in related environmental protection and resource conservation systems is critical,” it says.  

For more information, read the Council for Agricultural Science and Technology paper “Water and Land Issues Associated with Animal Agriculture: A U.S. Perspective,” at http://goo.gl/43pw6.


 

 

 

 

 

 

 

 

Japanese manufacturing facility increases copper recovery to increase profits

Fujitsu Facilities Ltd. (Kawasaki, Japan) has introduced a new wastewater treatment process to Japan. The company’s plant in Nagano, Japan, installed the country’s first treatment system that enables copper recovery from industrial wastewater. The process enables copper to be recycled at a profit, according to a Fujitsu news release.  

The Nagano plant produces printed circuit boards and has been working to improve the efficiency of copper recovery from its wastewater. It also has been working to reduce the amount of solids produced and chemicals consumed during production, the news release says.   

Fujitsu deployed the system on June 27. The system, which is produced by Toshiba Corp. (Tokyo), recovers at least 90% of copper from the solids. The copper then can be recycled for a profit, the news release says.  

Because the copper particles in the wastewater are very fine and difficult to filter, a coagulant typically is used to aid sedimentation to generate solids. But the new system uses a magnetic functional powder when filtering wastewater to remove copper using only a neutralizing agent. This reduces the types of chemicals needed to treat wastewater by 75%, lowering operational costs, space needed for the treatment process, and processing time. And because magnets can separate the powder after filtration, the powder can be recycled and reused in the system, the news release says. 

Before implementing the system, the plant generated 32 Mg/mo (35 ton/mo) of solids. With the new system, it now generates 4.5 Mg/mo (5 ton/mo) of solids that contain a high concentration of copper, which increases the solids’ value as a resource, the news release says.  

When factoring in revenue from selling the solids to recyclers, the system has reduced operational costs by 40%. Processing time and equipment space have each been cut in half, compared to the previous treatment system, the news release says. 

Fujitsu now is verifying results and gaining operational knowledge. It will consider implementing the system in the company’s other manufacturing facilities. Starting in October, the plant also plans to deploy copper oxide conversion technology, enabling it to process copper oxide and add value to the solids, the news release says. 

 

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