Synergistic effects of heterogeneous mature compost and aeration rate on humification and nitrogen fixing during kitchen waste composting.

Sludge mature compost (SMC) is notable for its high production, easy accessibility, and stable supply. This study investigated the impact of the SMC addition and different aeration rates on the humification and nitrogen fixing process during kitchen waste composting. The results demonstrated that addition of SMC prolonged the thermophilic phase, as a comparison, increased aeration shortened this phase.

Measuring and Modeling Mechanical Ventilation for Long-Term Environmental Monitoring in Large Commercial Laying Hen House.

Determining ventilation rates in commercial animal buildings has been technically challenging. This study aimed to develop an innovative method and a ventilation model and provide new insights into animal building ventilation. A layer house with 46 fans was studied over six months.

Impact of cellulolytic nitrogen-fixing composite inoculants on humification pathways and nitrogen cycling in kitchen waste composting.

Low humification and nitrogen loss pose substantial challenges to the resource utilization in kitchen waste composting. This study investigated the effects of brown-rot fungi (BRF), cellulolytic nitrogen fixing bacteria (CNFB), and their composite microbial inoculants (CMI) during composting. Results indicated that microbial inoculants extended the thermophilic phase and enhanced cellulose degradation.

A wearable real-time particulate monitor demonstrates that soaking hay reduces dust exposure.

Background: Affordable particulate matter (PM) monitors suitable for use on horses will facilitate the evaluation of PM mitigation methods and improve the management of equine asthma.

Objective: Calibrate a real-time wearable PM monitor (Black Beauty [BB]) and compare the PM exposures of horses fed dry or soaked hay.

Study Design: Laboratory calibration; complete cross-over feed trial.

The influence of using different types of modified vermiculite cover on ammonia mitigation from animal slurry storage: The role of sulfuric acid.

Animal slurry storage is an important ammonia (NH) emission source. Sulfuric acid (HSO)-modified vermiculite coverage is a new promising technology for controlling NH emission from slurry storage. However, the underlying mechanisms in controlling the mitigation effect remain unclear.

Hydrogen production promotion and energy saving in anaerobic co-fermentation of heat-treated sludge and food waste.

The objective of this paper is to gain insights into the synergistic advantage of anaerobic co-fermentation of heat-treated sludge (HS) with food waste (FW) and heat-treated food waste (HFW) for hydrogen production. The results showed that, compared with raw sludge (RS) mixed with FW (RS-FW), the co-substrate of HS mixed with either FW (HS-FW) or HFW (HS-HFW) effectively promoted hydrogen production, with HS-HFW promoted more than HS-FW. The maximum specific hydrogen production (MSHP) and the maximum hydrogen concentration (MHC) of HS-HFW were 40.

Effect of municipal sludge-based biochar produced at different pyrolysis temperatures on humification and oxytetracycline degradation of pig manure composting.

This study explored the influence of pyrolysis temperatures on the properties of municipal sludge-based biochar (MSB) and evaluated the impact of MSB on humification and oxytetracycline (OTC, a broad-spectrum antibiotic) degradation in pig manure composting. Three types of MSB were produced from sewage sludge pyrolyzed at 300 °C, 500 °C, and 700 °C, respectively. Results indicated that pyrolysis temperature adjusted the formation sequence of the functional groups in MSB, and higher pyrolysis temperatures enriched the aromaticity of the biochar and augmented the concentrations of humic precursor compounds.

Identified factors and predicted unidentified-factors affecting ammonia emissions from a swine building.

Large variabilities in ammonia (NH) released from animal manure and emitted from different livestock buildings were frequently reported, but the factors influencing the emissions were not sufficiently investigated. In this paper, continuously monitored data of NH emissions and other relevant environmental variables under controlled conditions in a 12-room experimental swine building for a 155-d complete wean-to-finish cycle were studied. Measurement data mining was conducted at both spatial and temporal dimensions using panel data analysis with heterogeneous time trends.

Computational Fluid Dynamics Modeling of a Broiler House Microclimate in Summer and Winter.

Appropriate microclimate conditions in broiler housing are critical for optimizing poultry production and ensuring the health and welfare of the birds. In this study, spatial variabilities of the microclimate in summer and winter seasons in a mechanically ventilated broiler house were modeled using the computational fluid dynamics (CFD) technique. Field measurements of temperature, relative humidity, and airspeeds were conducted in the house to compare the simulated results.

The effect of reduced CP, synthetic amino acid supplemented diets on growth performance and nutrient excretion in wean to Finish swine.

Mixed sex pigs (n = 720) were placed in 12 rooms (Purdue Swine Environmental Research Building) to measure the effect of reduced crude protein (CP), amino acid (AA)-supplemented diets on growth and the carcass. Pigs were blocked by body weight (BW) and gender and allotted to room and pen (10 mixed-sex pigs/pen). Pigs were fed a nine-phase, wean-finish program.

Summary of Known U.S. Injuries and Fatalities Involving Livestock Waste Storage, Handling, and Transport Operations: 1975-2019.

Highlights: Approximately ten cases were documented annually over the 44-year period; 48% were in the last decade and 28% were in the last three years, primarily due to more aggressive surveillance and on-line access to incident reports. A total of 389 incidents involving 459 individuals were documented, of which 59% were fatal; >85% of the victims were male, with an average age of 37. 49 rescue incidents involved a total of 119 secondary victims, indicating that approximately 26% of the victims were secondary victims, including first responders.

Long-term performance of three mesophilic anaerobic digesters to convert animal and agro-industrial wastes into organic fertilizer.

Few studies have investigated the performance of anaerobic digestion (AD) to convert animal and agro-industrial wastes to organic fertilizers over a long-term field conditions. This paper studied three large-scale mesophilic digesters (D1eD3) over two years for their effects on feedstocks, which were dairy manure for D1 and D2 and co-digestion mixed manure and agro-industrial wastes for D3. Hydraulic retention times (HRT) were 9 d for D1, 12 d for D2, and 34 d for D3.

Summary of Injuries and Fatalities Involving Livestock Manure Storage, Handling, and Transport Operations in Seven Central States: 1976-2019.

HIGHLIGHTS A total of 133 cases were documented in a seven-state region, with Iowa reporting 43% of the cases and asphyxiations accounting for 42% of all cases. Most victims were male (>79%) with an average age of 38 years. The overall fatality rate was 57%, and 16% of the victims were under the age of 21.

A critical review of advancement in scientific research on food animal welfare-related air pollution.

Air pollution generates hazardous pollutants that have resulted in safety, health, and other welfare issues of food animals. This paper reviewed scientific research advancement in food animal welfare-related air pollution based on 219 first-hand research publications in refereed journals (referred to as "RPs") over the past nine decades. Scientific studies in this area began in the 1930s.

Dynamic and 3-D spatial variations in manure characteristics in two commercial manure-belt laying hen houses.

Animal manure could be hazardous to human and animals if not managed properly. Laying hen manure in two commercial manure-belt houses was sampled in seven events over two years. A total of 124 samples was taken in randomly-selected 3-D space with 24 subspaces, composed of 3 sections × 4 sides × 2 floors in the houses.

Farm-Related Injuries and Fatalities Involving Children, Youth, and Young Workers during Manure Storage, Handling, and Transport.

Manure storage, handling, and transport facilities and equipment have been associated with life threatening hazards on many livestock farms. These hazards have been documented in prior research as including 1) exposure to toxic manure gases or lack of adequate oxygen in enclosed structures, which can be fatal to both humans and livestock; 2) below and above ground liquid manure storage structures that have the potential risk for drowning and falling; and 3) mechanical hazards associated with manure handling and transport equipment, including entanglement, road collisions, runover, and equipment failure. Over the past 40 years, Purdue University's Agricultural Safety and Health Program (PUASHP) has collected, documented, and maintained data regarding agricultural-related injuries and fatalities associated with agricultural confined spaces in the United States.

New insights into concentrations, sources and transformations of NH, NO, SO and PM at a commercial manure-belt layer house.

Pollutant gases and particulate matters (PM) from livestock facilities can affect the health of animals and farm workers and lead to great social environmental risks. This paper presents a comprehensive study on the characteristics of ammonia (NH), nitrogen oxides (NO), sulfur dioxide (SO) and PM (including PM and PM) in a 100,000-bird manure-belt layer house in suburb Beijing for three typical seasons of summer, autumn and winter. Indoor air was sampled at an exhaust fan of the mechanically ventilated commercial house.

Effects of antibiotic-free pig rearing on ammonia emissions from five pairs of swine rooms in a wean-to-finish experiment.

Antibiotic use and ammonia (NH) emissions during animal production are two environmental issues of worldwide concern. However, the role of antibiotics on NH emissions is still unknown. This study evaluated the effects of rearing pigs without antibiotics on NH emissions from a swine experimental building starting with 657 piglets during a wean-to-finish production cycle of 154 days.

Development of methodology to document and code farm-related injuries and fatalities involving manure storage, handling and transport - with summary of 2017 incidents.

As part of ongoing surveillance of fatalities and injuries involving agricultural confined spaces by Purdue University's Agricultural Safety and Health Program, nearly 300 cases involving manure storage, handling, and transport equipment and facilities have been documented over the past 30 years. With the exception of a summary of 77 fatalities published by Beaver and Field, these cases have not been previously analysed or published due to a lack of resources and the limitations of the Purdue Agricultural Confined Spaces Incident Database (PACSID) which was designed primarily for analysis of grain-related cases. These limitations included differences in terminology used to code case information in the PACSID and dissimilar causative and contributing factors.

Hydrogen sulfide emissions from a swine building affected by dietary crude protein.

Hydrogen sulfide (HS) is a toxic air pollutant at animal facilities; but the understanding of its generation and emission processes has been limited. This paper studied HS emissions during a complete cycle of wean-finish pigs from a research building, where 12 pig rooms were divided into three groups that were fed with standard feed (control), and 2.1-3.

Fuzzy comprehensive evaluation of multiple environmental factors for swine building assessment and control.

In confined swine buildings, temperature, humidity, and air quality are all important for animal health and productivity. However, the current swine building environmental control is only based on temperature; and evaluation and control methods based on multiple environmental factors are needed. In this paper, fuzzy comprehensive evaluation (FCE) theory was adopted for multi-factor assessment of environmental quality in two commercial swine buildings using real measurement data.

Mitigation of ammonia emissions from pig production using reduced dietary crude protein with amino acid supplementation.

To mitigate ammonia (NH) emissions from pig production and understand dynamic emission profiles, reduced dietary crude protein (CP) with amino acid supplementation was studied with 720 pigs in a 12-room research building for 155days that covered from weaned to finishing stages. The pigs were divided into three 4-room groups and fed with 2.1-3.

A prediction model of ammonia emission from a fattening pig room based on the indoor concentration using adaptive neuro fuzzy inference system.

Ammonia (NH) is considered one of the significant pollutions contributor to indoor air quality and odor gas emission from swine house because of the negative impact on the health of pigs, the workers and local environment. Prediction models could provide a reasonable way for pig industries and environment regulatory to determine environment control strategies and give an effective method to evaluate the air quality. The adaptive neuro fuzzy inference system (ANFIS) simulates human's vague thinking manner to solve the ambiguity and nonlinear problems which are difficult to be processed by conventional mathematics.

Characteristics of pollutant gas releases from swine, dairy, beef, and layer manure, and municipal wastewater.

Knowledge about characteristics of gas releases from various types of organic wastes can assist in developing gas pollution reduction technologies and establishing environmental regulations. Five different organic wastes, i.e.