Electrical properties of organic and respirable swine dusts.

Posted in: Environment by admin on January 1, 1995 | No Comments

The electrical resistivity and collection efficiency of pig dust were determined to investigate the use of electrostatic precipitation in removing airborne dust from pig housing. Pig dust was compared with 4 other organic dusts in resistivity and collection experiments: flour, icing sugar, maize starch and milk powder. The electrical resistivity for each of the dusts was within the “medium” resistivity range. An electrostatic precipitator collected the flour, icing sugar, maize starch, milk powder and pig dust with mass collection efficiencies of 92.5, 23.9, 71.0, 45.7 and 67.3%, respectively. For each of the 5 dusts, particles <1 um were collected less efficiently than particles >1 um.

Incidence and transmission of antibiotic resistance in Campylobacter jejuni and Campylobacter coli.

Posted in: Environment by admin on | No Comments

EWEES: A European Waste Engineering Expert System

Posted in: Environment by admin on | No Comments

EWEES is being produced in collaboration with many research teams in Europe (U.K., Greece, the Netherlands, Ireland, Italy).EWEES is meant to help avoid farm pollution by better decision making. The expert system is designed to act as a human expert would do, by logical reasoning process to approach the problem solving in a broad way. Steps are followed in the research of solutions by the system. First, the user gives the main constraints and requirement to characterize the problem; secondly a system of rules are applied in order to find the technical approaches that are more likely to solve the problem. Several alternatives can be presented and explained to the user and recommendations are made considering the input information given. The 3rd step is when needed detailed engineering solutions and finally the user can calculate and compare the costs of the proposed solutions. Technical, managerial, economic and legislative information are integrated to the expert system.

This system is intended to help the human experts in the field in their analysis of different situations. Human touches are always needed for unusual problems and also in analyzing the options presented in keeping the broad perspective of each specific situation. The precision of the elements and information put in this expert system have a direct impact on the exactitude of the results.

A farm scale study on the use of De-Odorase for reducing odour and ammonia emissions from intensive fattening piggeries.

Posted in: Environment by admin on | No Comments

The methodology used for this experiment is very interesting and efficient for farm scale testing of additives. The availability of many building made repetition possible which improve greatly the results validity with satatistical analysis. De-Odorase can reduce ammonia concentration and emission (considering the ventilation rates) by 26% however no significant odour concentration and emission reduction could be measured.

Water Quality and the North Carolina Swine Industry

Posted in: Environment by admin on | No Comments

Water quality is discussed in this document and the swine production activities are also presented in a water quality perspective. If the production activities are not well managed, water quality can be endangered. Well designed lagoons built with clay liners can serve for some anaerobic treatment under North Carolina conditions. However, old lagoons that don’t have a liner present a threat to surface and groundwater quality. Nitrate fund at concentration higher than 10 part per million (ppm also equal to 10 mg/L) in water present a health risk to people that drink it. In some Coastal Plain counties in North Carolina, a testing done on over 10 000 wells showed that as many as 10% of those wells had nitrate concentration higher than 10 ppm. Investigations are needed to determine if only the hog production can be accountable for those contamination as nitrate can come from other sources. A greater potential threat comes from the contamination of surface water as nitrate and other nutrients such as phosphorus leads to aquatic plants and algae development and can lead to eutrophication. As oxygen in the water is used by the plants and for the degradation of organic compounds from those plants, less oxygen is available to fishes and marine animals that can die. Proper manure management is needed and riparian buffers can also protect the streams and rivers by nutrients caption. The management of dead animals is also important as improper disposal can lead to groundwater contamination. In North Carolina wetlands constructions are being tested to verify their filtering capacities. Research is also being done in order to separate and collect nutrients from the manure before spreading and to use. The struvite is a salt that forms during the wastewater handling systems and could be used as a slow-release fertilizer. Swine production and water quality are two elements that can go together however important considerations have to be made such as a control animal density per watershed determined a complete study of this watershed and its nutrients sources (N and P) and also a good management of each farms. Comparison of the regulations of the Southeastern states is also.

The elements presented are interesting and give a good portrait of the swine production and its threat to water quality. Part of the solutions given have to be considered in their climatic situation as treatments in lagoon and in wetlands stops when the winter temperatures are low.

Removal of airborne swine dust by electrostatic precipitation.

Posted in: Environment by admin on | No Comments

An electrostatic precipitator used in conjunction with a recirculation duct was developed to remove airborne pig dust from an environmental chamber. The collection efficiency of the precipitator was evaluated by using 3 applied voltage levels (-10.3, -11.0 and -12.1 kV d.c.) and 3 airspeeds (0.55, 0.76 and 0.95 m/s). The overall collection efficiency of the precipitator ranged from 18.5 to 96.4% at applied voltages of -10.3 and -12.1 kV, respectively. Removal efficiency was highest at 0.76 m/s for all applied voltages. An applied voltage of -12.1 kV produced ozone levels of 0.21 ppm, which exceeded the recommended level of 0.1 ppm.

Animal waste – the smell of success or the stench of trouble?

Posted in: Environment by admin on | No Comments

In the past odours resulting from livestock production was less of an problematic. However, over time poultry facilities have intensified significantly. With this increase also came an increase in manure production, odours, and the possibility of water contamination. Zoning and environmental agencies have not been able to develop regulations to keep up with the expansion of these facilities. For the time being companies continue to build large facilities without taking any of these factors into conisderation. This half-hazard approach to livestock development may lead to the development of conflicts in the future.

Bilan environnemental et zootechnique de l'engraissement de 4 lots de porcs sur litiere biomaitraisee

Posted in: Environment by admin on | No Comments

An experiment was realized in two identical rooms that could accommodate 17 growing pigs. The pigs were on deep litter, one room using sawdust and the other straw. For the sawdust, a 50 cm layer thick layer was place at the beginning of the experiment and 4 consecutive fattening periods were realized. Once a week the feces produced were dung in the litter and a microbial product was added to it. Addition of fresh sawdust was done along the fattening period and the total amount needed was evaluated at 100 kg per pig. After the 4th fattening period the composted resulting from the litter degradation was 109 kg and 0.18 m3. The straw litter was managed the same way than the saw dust however after the first fattening period, the litter was removed and replaced by sawdust for the remaining of the experiment. The labor needed to mix the straw bed was more important than for sawdust and considered to heavy to be continued. For the 3 fattening periods remaining, the microbial product was added weekly in this room however it was not incorporated to the litter. The total amount of straw used equaled 49 kg/pig and the total compost produced from the 3 fattening period on sawdust equaled 164 kg/pig. The ammonia concentration was 68% higher in the room with the sawdust litter compared to the straw litter however the odour was stronger in the room with the straw bed. The growth rate of the pigs raised on deep litter was significantly higher than for pigs kept on slatted floor however no significant differences could be noticed in the carcass quality.

The research realized by this team showed that different litter material have different impacts on the ambient conditions. Higher dust concentrations have been measured with the sawdust litter and higher NH3 concentration were obtained with straw deep-litter.

The Effect of Environmental Odors Emanating from Commercial Swine Operations on the Mood of Nearby Residents

Posted in: Environment by admin on | No Comments

The Profile of Mood States (POMS) was used to determine the effect of environmental odors caused by intensive hogs operations on the mood of nearby residents. 44 experimental subjects rated their mood using a POMS questionnaire and their rating of six POMS factors and the total mood disturbance (TMD) was compared to the ones of 44 control subjects. Gender, race, age and years of education were considered in order to have control and experimental subjects that could be compared. The results showed that when comparing the six POMS factors and the TMD, statistically significant differences were obtained between the experimental group and the control. Consulting the POMS questionnaire the results showed that the persons leaving closer to the swine facilities experienced the odors reported more tension, more depression, more anger, more confusion, more fatigue and less vigor than the control subjects. Mood disturbances were also reported more frequently by the treatment group. The mood impairment reported could be partly explained by both innate physiological responses and learned responses.
The effects of odors on nearby residents of commercial swine operations are presented following a study on profile of mood states. It is important to better understand the human reactions to odors and also to evaluate and verify the consequence of odors exposure on health and well being of swine operations neighbors. Odor thresholds associated with the those reactions could be help define zoning or odor abatement systems for specific situations.

Manure Nutrient Management

Posted in: Environment by admin on | No Comments

The cycle of nutrient from animal feed to manure to soil and than to crops is an efficient and environmentally sound practice for surface and groundwater if it is done properly done. Good manure management should include all the steps from storage to spreading. The document deals with proper ways to valorize manure particularly in determining the land surface needed for manure application. Two methods for such evaluation and optimization of the manure in order to maximize returns from the nutrients in the manure and avoid environmental consequences from over application are presented. The first method is for a new facility by evaluating the land needed and the second one is for an existent facility by fine tuning the operations. The first step is to set realistic yields goal, as yields goal that are too high will lead to over application of manure and nutrients wastes that could cause leaching and goal that are too low will result in less manure applied and less yield. The subsequent steps are presented for all the calculation for the two possible situations. For soils presenting a P concentration in the soil lower than 30 ppm, the application rate should be done according N requirements. For soil with high P content or if required by regulation, the application rate can be calculated considering P as the limiting element. Commercial fertilizer can than be used to complete the fertilizer requirements of certain elements in order to maximize the yield. Manure and soil sample should be taken every year to evaluate the situation and in order to make appropriate evaluations of the application rates needed.

This document is very interesting and contains a good tool to evaluate the land needed to maximize the nutrients value in manure and to make sure that environmental impacts from manure application are as low as possible.