Cost-Effective Solution for Treating Industrial Wastewater
Compact and modular wastewater technology Made in Germany
MODERNIZATION and development are characterized by greater industrialization and productivity. Bigger output of products more often than not creates undesirable byproducts such as pollutants, including wastewater, which if unchecked can lead to health and environmental problems. In fact the State Environmental Protection Agency (SEPA), which said in May 2006 that China's pollution problems cost the country more than USD 200 billion a year, has prioritized water pollution control among its top seven environmental targets. But even the SEPA concedes that China will be hard pressed to meet environmental targets without the cooperation of all sectors, including the food and beverage industry.
Responsible and ethical industries are committed to protecting the environment by limiting the pollutants they emit or release and by effective recycling and reuse of resources. When it comes to water, for instance, wastewater can be treated to remove organic material and solids before disposal or, even better, reuse. In many developed countries industrial effluents must be treated to reduce biological and chemical oxygen demand - BOD and COD - to acceptable levels before being released into sewage systems or water resource.
BOD is the rate at which microorganisms use the oxygen in water or wastewater. Depositing high BOD waste into water resources will allow pathogenic species of bacteria to proliferate, destroy marine life due to insufficient oxygen in the water and cause odors, among other hazards. High COD waste containing hazardous chemicals can poison the natural population of waste-degrading bacteria, thereby breaking the food chain and leading to all the problems associated with a high BOD waste. High levels of these chemicals can also directly poison higher life forms.
Effluents from food operations
Wastewater generated from food operations is generally nontoxic, but has high concentrations of BOD and suspended solids (SS). Most organic compounds will be completely converted to CO2 and water by the growth of aerobic microorganisms and can be removed from effluent water in this way at relatively low cost. In conventional aerobic methods, growth of the biomass is encouraged in with the introduction of air against the pressure of the water column, which causes high operation costs. Anaerobic systems do away with oxygen, of course, but start-up and stable operation of these methods are difficult and can be as costly.
The constituents of food and agriculture wastewater are often complex to predict due to the differences in BOD and pH in effluents from vegetable, fruit, and meat products and due to the seasonal nature of food processing. Very significant quantities of oil or fats may also be present. Food processing effluents may contain flavorings, coloring material, acids or alkali, and other processing aids
Processing of food from raw materials requires large volumes of high grade water. Vegetable washing generates waters with high loads of particulate matter and some dissolved organics. It may also contain surfactants.
Animal slaughter and processing produces very strong organic waste from body fluids, such as blood, and gut contents. This wastewater is frequently contaminated by significant levels of antibiotics and growth hormones from the animals and by a variety of pesticides used to control external parasites. Brewing produces wastes generated from fermenting which are often rich in plant organic material.
The TFR Technology
One recent technology now being used in 50 plants worldwide is able to offer high performance with minimal operating and maintenance costs. Developed in Germany, the TFR Bioreactor from DAS Environmental Expert can treat the organic load of industrial production effluent by biological microorganisms. The system is less costly because air does not need to be introduced into the wastewater to encourage growth of the biomass. In contrast to the conventional technology, the carrier material is not submerged in the wastewater. Instead, the TFR Bioreactor uses carrier material made of small plastic balls on which the biomass can grow and be aerated easily.
Effluent water trickles continuously from top to bottom over the packed bed, and ambient air is ventilated in the opposite direction. The biomass in the reactor is supplied with the, necessary air from the environment under almost no pressure by a simple fan that blows the air into the base of the reactor. The system has low energy consumption since the air does not have to be forced in under high pressure and no artificial movement of the biomass and its carrier material is needed in the reactor.
This unhindered contact between the wastewater and high-density population of microorganisms as well as the well-aerated growth bed is optimal for chemical transfer between biomass, water pollutants and oxygen in excess are the basis for the very high and stable biological degradation of pollutants. Together with optimally adjusted microorganism populations, this results in a high and stable decomposition in a relatively small space, even with fluctuating wastewater constituents from all types of food processing effluents.
The TFR system assures the reduction of organic load (COD/BOD5), of solid load (precipitable I filtrable matter) and of nitrogen compounds (ammonia, nitrite). Intensive treatment of very low, very high or average concentrated wastewater is possible before direct or indirect disposal or recycling.
Simple and low cost to install
Because of the simple principle and the high efficiency the investment cost is low, and so are running cost and maintenance needs - making the system an affordable investment even for a small-sized plant. What's more, the automated system is almost completely wear-free thanks to its simple design and modular plastic components. Because the components are made from PE, there is no fear of corrosion, further reducing maintenance cost and times. Even the carrier material is stable and doesn't need to be exchanged. Growing biomass is flushed out in an automatic regeneration cycle. The systems can be customized for the specific conditions with the aid of tests in the DAS laboratory and pilot trials of the tests plants on site. This guarantees not only their function but also an optimum-sized plant. When extension is called for, the modular setup allows easy installation for the expansion.
Compact biological wastewater treatment systems according to the TFR principle can be used for the pre-treatment of wastewater before this is discharged into the company's own or municipal sewage plants, for the complete cleaning of the wastewater before its discharge into watercourses and for the production of industrial water. This efficient technology can be used to treat a wide variety of wastewaters from industry, municipalities and agriculture in China, which has made known that it is serious about reducing the potential hazards caused by unbridled pollution.