Tofu is a food that is favored by most of the people in Indonesia. Tofu is made from raw materials such as soybean (Glysine max) which is known to contain a wide variety of proteins that are needed by the human body. Industry know can be found in a variety of areas, both rural and urban-scale cottage industry to big industry. Know the production process in addition to primary products such know, also produce waste byproducts in the form of liquids or solids. It is an impact on the environment due to industrial waste. In general, solid waste other than used as food are also used as animal feed, while the liquid waste discharged directly into the environment. This idea wastewater has a high organic matter content. Without properly handling process, effluent know cause negative impacts such as water pollution, sources of disease, odor, increase mosquito breeding, and reduce the beauty of the surrounding environment.
In Indonesia, a lot of know-scale factories that do not have a household wastewater treatment process. Unwillingness of the factory owners know to treat liquid waste due to complex and inefficient sewage treatment process, plus it generates added value. In fact, tofu liquid waste has a high organic matter content that has the potential to be utilized as liquid fertilizer.
The amount of wastewater generated by the industry makers know approximately 15-20 l / kg of soybean, whereas approximately pencemarnya materials for TSS at 30 kg / kg of raw material soybeans, BOD 65 g / kg of soybean and COD 130 g / kg of soybean (EMDI & BAPEDAL, 1994).
Waste knew known to contain BOD (Biological Oxygen Demand) of 5000-10000 mg / l and COD (Chemical Oxygen Demand) 7000-12000 mg / l and very low acidity level, which is 4-5. If the waste waters discharged into biological processes will experience the presence of anaerobic microorganisms. This process degrades only 70-80% levels of pollutants in waste out the body still contains water and organic matter in the form of nitrogen and phosphate. Biological processes can also produce byproducts derived from the decomposition of organic material (Kaswinarni, Fibria. 2007. Technical Review Solid and Liquid Waste Treatment Industry Know).
Not a secret anymore that we have greatly decreased soil fertility. Fertilizer application which sometimes does not bring much positive impact on the expected production. The decline in fertility is due to diforsirnya ground for years without any soil quality improvement efforts by way of return of organic matter.
Many ways have been sought to improve the fertility of our soil of which is produced organically labeled product range include POC (liquid organic fertilizer) and organic pesticides. This is done also to reduce dependence on chemical fertilizers and pesticides. Making a variety of organic products in order to prioritize the utilization of waste directed many local ingredients available around us.
Utilization of liquid waste into fertilizer and pesticides out an alternative to overcome the disadvantages of environmental pollution directly felt by humans. Making Fertilizer effluent know about the same as Liquid Organic Fertilizer, the difference is only in the waste water medium soybeans.
Utilization of waste know as fertilizer can also provide keutungan for its users because in addition to reducing the use of chemical fertilizers (urea), it can also provide additional income for producers of liquid fertilizer from the waste out. Prices of liquid fertilizer out of waste is typically sold at Rp 4,000/liter.
With proper management of everything produced by the manufacturing industry knows this, will automatically provide added value to these products and more environmentally friendly. In addition, the management of waste to this product can streamline costs, materials used, and the energy to make new products from waste materials.