Comprehensive Guide to Livestock & Poultry Farming Wastewater Treatment: Process Selection, Zero Liquid Discharge (ZLD) Realization & Environment Compliance Implementation

Abstract
Against the backdrop of tightened environmental supervision over the livestock and poultry breeding industry in 2026, livestock wastewater treatment technology has become an essential demand for farms to operate in compliance with regulations, cut costs and improve efficiency. Beyond basic process introduction, this paper thoroughly analyzes the core logic, practical schemes and application essentials of livestock wastewater treatment technology from four dimensions: technical iteration, scenario-based process selection, zero liquid discharge implementation and long-term operation & maintenance. It provides directly implementable technical solutions for farms of various scales and breeding types, helping enterprises achieve standard-compliant wastewater discharge and resource recycling, and completely avoid risks of environmental penalties.

I. Livestock Wastewater Treatment Technology: Solving Core Environmental Pain Points of Breeding Industry

With the full implementation of the Regulations on the Prevention and Control of Pollution from Large-scale Livestock and Poultry Breeding, random discharge of breeding wastewater has become a key target of industrial rectification. Characterized by high organic matter, high ammonia nitrogen and high suspended solids, breeding wastewater cannot meet discharge standards merely through traditional sedimentation and airing, and is highly likely to trigger ecological problems such as water eutrophication, soil contamination and groundwater pollution.
Livestock wastewater treatment technology is a special environmental treatment technology developed targeting the properties of breeding wastewater. By adopting combined processes including physical separation, biodegradation, ecological purification and resource conversion, it realizes three major goals: pollutant removal, water purification and manure recycling. Compared with general wastewater treatment technologies, it is better adapted to the water quality characteristics of breeding wastewater, featuring controllable investment, simple operation & maintenance and high resource recovery rate, serving as indispensable technical support for modern ecological breeding.
II. Core Classification of Livestock Wastewater Treatment Technology: Comparison Between Traditional and Innovative Technologies
Currently, four major categories of livestock wastewater treatment technologies are widely applied in the industry. Farms can make flexible selections according to their own scale and discharge standards:
(1) Physical Treatment Technology: Basic Barrier for Livestock Wastewater Treatment
As the prepositive core link of livestock wastewater treatment, physical treatment involves no chemical reactions and mainly removes solid impurities in wastewater to reduce the load of subsequent treatment.
Core technologies: Bar interception, screw solid-liquid separation, centrifugal dewatering, sedimentation tank precipitation
Technical advantages: Low cost, no consumables, low equipment failure rate; the removal rate of SS (suspended solids) can exceed 85%
Application scenarios: Pretreatment section of all farms; separated manure residues can be directly used for organic fertilizer production
(2) Biochemical Treatment Technology: Core Degradation Link of Livestock Wastewater Treatment
Biochemical treatment is the core of livestock wastewater treatment technology. Microbial flora decompose pollutants such as COD, ammonia nitrogen and total phosphorus in wastewater, which is the key to reaching discharge standards.
Anaerobic biochemical technology: Black membrane biogas digester, UASB reactor, IC reactor, which efficiently degrade organic matter and produce biogas energy simultaneously
Aerobic biochemical technology: Activated sludge process, contact oxidation process, MBR membrane bioreactor, which realize advanced nitrogen and phosphorus removal and deliver clear effluent
Combined biochemical technology: A/O and A²/O processes integrating advantages of anaerobic and aerobic treatment, with pollutant removal rate over 90%
(3) Ecological Treatment Technology: Preferred Low-cost Solution for Standard Discharge
Relying on natural ecological systems to purify water quality, ecological treatment technology boasts the lowest operation & maintenance cost among all livestock wastewater treatment technologies, suitable for small and medium-sized farms and rural areas.
Core technologies: Constructed wetland, oxidation pond, ecological ditch, land infiltration
Technical advantages: No professional maintenance required, zero power consumption, landscaping effect
Applicable standards: Non-direct discharge standards such as farmland irrigation and woodland reuse
(4) Resource Utilization Treatment Technology: Circular Technology to Turn Waste into Valuable Resources
Resource utilization represents the development direction of livestock wastewater treatment technology, breaking the single logic of pollution control and realizing resource conversion of manure.
Core technologies: Biogas power generation technology, organic fertilizer fermentation technology, reclaimed water reuse technology
Core value: Treated wastewater can be reused for barn flushing; manure residues are processed into commercial organic fertilizer; biogas is used for power generation and heating, achieving a win-win situation of environmental protection and economic benefits
III. Implementation of Livestock Wastewater Treatment Technology: Standardized Zero Liquid Discharge Process Flow
With mature livestock wastewater treatment technologies, large-scale farms can achieve zero liquid discharge and full utilization of manure. The standardized industry-wide process flow is as follows:
Collection link: Rainwater and sewage diversion, dedicated pipelines for manure collection to avoid increased treatment load caused by rainwater mixing
Pretreatment link: Bar screen → solid-liquid separation → regulating tank to remove solid impurities and balance water quality and volume
Core treatment link: Anaerobic reactor → A/O aerobic tank → MBR membrane tank for advanced pollutant degradation
Advanced purification link: Ecological wetland → disinfection tank to kill pathogenic bacteria and guarantee standard-compliant effluent
Resource utilization link: Manure residue fermentation for fertilizer → biogas recovery and utilization → reclaimed water reuse to form a closed-loop circulation system
Simplified process for small farms: Solid-liquid separation → sedimentation tank → ecological pond → farmland irrigation, enabling low-cost implementation of livestock wastewater treatment technology.
IV. Selection Guide of Livestock Wastewater Treatment Technology for Different Breeding Scenarios
Livestock wastewater treatment technology is not fixed; precise selection based on breeding type and scale can guarantee stable treatment performance:
Large-scale pig / beef cattle breeding: Prioritize combined anaerobic + aerobic + resource utilization technology for high-concentration wastewater with high COD and ammonia nitrogen
Layer / broiler breeding: Small wastewater volume with many impurities; solid-liquid separation + contact oxidation + ecological treatment technology is recommended
Factory aquaculture: MBR membrane + ozone disinfection technology is the first choice for tail water purification to realize recirculating aquaculture
Individual scattered / small farms: Prioritize ecological treatment + simple biochemical technology to cut investment and operation & maintenance costs
V. Long-term Operation & Maintenance of Livestock Wastewater Treatment Technology: Core Guarantee for Standard Discharge
Even the most advanced livestock wastewater treatment technology cannot sustain standard effluent without standardized maintenance. Farms need to focus on three key O&M points:
Equipment maintenance: Regularly clean bar screens, overhaul aeration equipment and replace membrane modules to ensure normal operation of treatment facilities
Water quality monitoring: Periodically test indicators including COD, ammonia nitrogen and total phosphorus, and adjust parameters such as microbial flora and aeration volume according to water quality changes
Cost control: Give priority to resource utilization technology; offset treatment costs through organic fertilizer sales and biogas utilization to realize "zero-cost pollution control"
VI. Development Trends of Livestock Wastewater Treatment Technology in 2026
Current livestock wastewater treatment technology is upgrading toward intelligence, low carbonization and integration:
Intelligence: Equipped with online monitoring systems to realize automatic water quality monitoring and unattended equipment operation
Integration: Integrated livestock wastewater treatment equipment featuring small footprint, fast installation and plug-and-play, applicable to small and medium-sized farms
Low carbonization: Strengthen energy recovery and reduce energy consumption in treatment processes, complying with national dual-carbon policy requirements
Standardization: Uniform national technical specifications and discharge standards will make livestock wastewater treatment technologies more standardized and popularized
Conclusion
Livestock wastewater treatment technology serves as the core technical support for the green development of livestock and poultry breeding industry, as well as the bottom-line requirement for farms to operate compliantly. From basic physical treatment to high-end resource recycling, from zero liquid discharge processes for large-scale farms to simple schemes for individual farmers, scientific application of livestock wastewater treatment technology can thoroughly eliminate wastewater pollution and tap the resource value of manure. In the future, with continuous technical iteration, livestock wastewater treatment technology will further lower application thresholds, helping the whole industry unify ecological, economic and social benefits.