Views: 5 Author: Site Editor Publish Time: 2018-10-30 Origin: Site
The harm of livestock and poultry breeding wastewater to the environment
As society progresses, the technology used in livestock and poultry breeding has become increasingly widespread and specialized. In comparison to the traditional method of scattered farming, adopting a large-scale approach can significantly enhance productivity, optimize feed utilization, lower production expenses, and boost economic gains. Nevertheless, this intensified farming practice also results in a surplus of waste and a significant rise in water consumption, leading to substantial strain on the ecological system.
Characteristics of wastewater
The aquaculture wastewater has typical "three high" characteristics------high CODcr, high ammonia nitrogen and high SS. Taking pig farm as an example, the investigation of wastewater quantity and quality of three kinds for dung cleaning processes is shown in Table 1 as below.
The harm to water bodies
Aquaculture wastewater is a kind of high concentration organic wastewater containing a large number of pathogens. When a large number of organic substances enter the water body, the decomposition of organic substances will consume a large amount of dissolved oxygen in the water, making the water odor and resulting in a large number of deaths of aquatic organisms, while nitrogen and phosphorus can make the water eutrophication.
The harm to atmospheric environment
Under anaerobic conditions, livestock and poultry breeding wastewater will produce a large number of NH3, H2S and other odorous gases. These odorous gases will affect and endanger the health of feeders and the surrounding residents.
The harm to farmland and crops
Livestock and poultry breeding wastewater contains much more nitrogen, phosphorus, potassium and other nutrients. If it is used directly, continuously, excessively without any treatment, it will cause adverse effects on the growth of soil and crops, such as crop yield reduction, delayed maturity and affecting the production of follow-up crops.
Wastewater treatment
Regardless of the methods used to treat wastewater from livestock and poultry farms, the first step is always solid-liquid separation. Currently, numerous countries have advanced technology and equipment for this process, including screw sludge dewatering machines, horizontal centrifuges, and filter presses.
BOEEP has optimized the design of screw sludge dewatering machine. Besides, through the selection of flocculants, the machine is fully suitable for the solid-liquid separation of livestock and poultry breeding biogas residue. The application in many cases of sludge dewatering treatment of livestock and poultry breeding wastewater shows that the separation effect of the screw sludge dewatering is very ideal, and has been unanimously recognized by the users, and is highly praised.
Summary
Livestock and poultry breeding is a crucial industry for pollution prevention and control in many countries. The treatment of wastewater has become a significant concern. Livestock and poultry breeding wastewater is characterized by high levels of CODcr, ammonia nitrogen, and SS. Current single treatment methods are insufficient in meeting wastewater discharge standards. Therefore, it is necessary to employ a combined treatment method based on the type of aquaculture, excrement removal methods, and water quantity and quality. Additionally, factors such as investment, daily operation costs, and operational convenience must be considered.
To effectively prevent and control pollution in livestock and poultry breeding, and minimize the discharge of wastewater and use of chemicals in the environment, we must focus on achieving both a harmless treatment process and the recycling of treated wastewater. By doing so, we can effectively protect and enhance the rural ecological environment.
