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Over the past 15 years, there have been numerous fatalities related to working with animal slurry. Working with cattle slurry releases toxic gases, in particular, hydrogen sulphide (H2S), which can cause acute central nervous system toxicity, breathing difficulties, and death if exposed to high concentrations. Real-time measurements of H2S gas were taken over distance and time, during the stirring of cattle slurry on farms. Gas was measured at eight slurry stores with differing typical configurations of indoor or outdoor stores and with or without slatted flooring. Highest H2S gas levels were measured from indoor stores under slatted floors, and generally at positions closest to the stirrer or the point of maximum stirring, with levels decreasing with distance from source. Most of the data indicate H2S gas levels increase very rapidly after stirring starts, and mostly decline to baseline levels within 30 min post start of stirring. There were, however, circumstances where gas levels remained high and only started to decline once the stirrer had stopped. H2S gas levels at all farms, at all positions measured were consistently below 10 ppm within 30 min of the stirrer being stopped. The current data highlight areas of the farm and ways of working that have the potential for workers and others to be at risk of exposure to toxic slurry gases. The area should be left to ventilate naturally for at least 30 min after the stirrer has been stopped before re-entering buildings. Influencing the design of stirring equipment and future slurry stores would likely reduce the risk of worker exposure to slurry gases. [ABSTRACT FROM AUTHOR]

As a by-product of the coal washing process, the methods involving the resource utilization of coal slime are very few because of its strong agglomeration and large water content. In this work, we propose a new way to dispose of coal slime, which involves preparing semi-coke water slurry (SCWS) with coal slime. When using sodium humate as dispersant at a dosage of 0.8 wt%, the solid concentration of ordinary SCWS reached a maximum (63.8 wt%) , and the concentration improved to 65.3 wt% after adding 15 wt% coal slime, and the calorific value of the slurry (18.07 MJ/kg) that can meet the Chinese standard (GB/T 18855–2002). The role of coal slime in improving the ability of SCWS is to optimize the particle size distribution as a small size material; additionally, it can improve the hydrophilicity of particulates through oxygen-containing groups and minerals, which increased the performance of SCWS. Image 1 • An environment-friendly slurry fuel was prepared by semi-coke and coal slime. • The semi-coke water slurry (SCWS) has good slurry ability and high calorific value. • The solid concentration of SCWS containing 15 wt% coal slime reached the maximum. • The action mechanism of coal slime in SCWS on the slurry ability was proposed. [ABSTRACT FROM AUTHOR]

The UK Health and Safety Executive has investigated several incidents of workplace accidents involving hydrogen sulphide exposure in recent years. Biological monitoring has been used in some incidents to determine the cause of unconsciousness resulting from these incidents and as a supporting evidence in regulatory enforcement. This paper reports on three case incidents and discusses the use of biological monitoring in such cases. Biological monitoring has a role in identifying hydrogen sulphide exposure in incidents, whether these are occupational or in the wider environment. Sample type, time of collection and sample storage are important factors in the applicability of this technique. For non-fatal incidents, multiple urine samples are recommended at two or more time points between the incident and 15 h post-exposure. For routine occupational monitoring, post-shift samples should be adequate. Due to endogenous levels of urinary thiosulphate, it is likely that exposures in excess of 12 ppm for 30 min (or 360 ppm/min equivalent) would be detectable using biological monitoring. This is within the Acute Exposure Guideline Level 2 (the level of the chemical in air at or above which there may be irreversible or other serious long-lasting effects or impaired ability to escape) for hydrogen sulphide. [ABSTRACT FROM AUTHOR]

Highlights: [•] Unusual dry climatic conditions affected the SW England in spring and summer in 2011. [•] Low N2O fluxes were observed after the fertilization with slurry and ammonium nitrate. [•] High losses of N by ammonia volatilization and plant N offtake were observed. [•] Dry conditions also reduced the rate of CH4 production in plots fertilized with slurry. [•] Highest CO2 fluxes observed in spring were related to dry and warm weather conditions. [ABSTRACT FROM AUTHOR]

Abstract: The combined farm animal population is considerably larger than the human one in the United Kingdom, implying a possibly important contribution to the environmental load of steroid hormones entering water. To make comparisons on the amount of steroid hormones produced by the different livestock, information was gathered on the structure of the UK farm animal populations and the amount of hormones excreted by animals at each of their life stages. An individual normalised dairy cow excretes two orders of magnitude more, and a normalised pig excretes more than one order of magnitude more steroid oestrogens than a normalised human. In terms of excretion, the combined farm animal population (including sheep and poultry) probably generates around four times more oestrogens than the human population in the UK. The biggest contributor on the animal side is the relatively small dairy cow population. If steroid oestrogens behave like herbicides, in which a worst case loss to surface waters is around 1%, then it could be argued that farm animals are responsible for 15% of all the oestrogens in UK waters. When simulations were made with the MACRO pesticide leaching model, predicted concentrations for field drains failed to exceed 1 ng/L. The rapid biodegradation rates, and high sorption rates taken from the literature and used in the model suggested less than 0.001% of oestrogens would reach the field drains. This survey suggests that direct excretion of steroid hormones by animals into water courses, or discharges from farmyard drains, are likely to be more important sources of contamination rather than via normal agricultural scenarios. [Copyright &y& Elsevier]

In both the United States and the United Kingdom, slurry walls are used as vertical barriers to control groundwater flow and to contain contaminants as part of waste containment systems. In the United States, slurry walls are commonly constructed using soil-bentonite (SB) and the barrier typically consists of a mixture of select soil, bentonite, and bentonite-water slurry. Alternatively, in the United Kingdom, the barrier wall comprises a mixture of cement, blast furnace slag, and bentonite-water slurry. After a comparison of the two techniques, this paper presents the results of permeability and unconfined compressive strength tests on twenty-one different mixtures of slag-cement-bentonite (slag-CB). The slurry wall materials tested in this study were prepared using sample formulations originating in the United Kingdom and materials originating in the United States. Unconfined compression tests were performed on samples after one month of curing, while permeability tests were performed after one, two, three, six, and twelve months of curing. For the mixtures tested and cured twelve months, two mixtures (one having 20% cementitious material with 70% slag replacement and another having 15% cementitious material with 80% slag replacement) were found to have the lowest hydraulic conductivity (2×10-8 cm/s). The data show that 0 to 60% slag replacement had little effect on hydraulic conductivity of the resulting slag-CB mixtures. However, the hydraulic conductivity drastically decreases as the slag replacement increases from 70 to 80%. As expected, the unconfined compressive strength increased as the cementitious material content increased from 10 to 15 to 20%. The slag-CB consolidates rapidly and has compression characteristics similar to other high moisture materials. [ABSTRACT FROM AUTHOR]

Approximately 20% of pig slurry in the UK is applied to land as dilute slurry (<2% dry matter content) via irrigation systems, which may result in larger emissions of ammonia (NH3) to the atmosphere than conventional application techniques. This study aimed to quantify this source under UK conditions and to assess the possibilities for emission abatement using alternative application techniques. Methodology was developed to measure emissions during irrigation, from both raingun- and boom-mounted splashplate systems. Measurements were also made following irrigation at both field- and small-plot scales. Emissions during irrigation of pig slurry to land were small, representing <0·1–2·5% of the total ammoniacal N (TAN) applied. Emissions from the land surface following irrigation were also small, typically amounting to only 10% of the TAN applied. Application via trailing hoses (band spreading) gave some reductions in emission for applications to growing crops, but no reduction when used on cereal stubble. Irrigation of dilute pig slurries does not therefore represent a major source of NH3 emission in the UK and, based on the results of this study, replacement of raingun or splashplate irrigation systems with trailing hose booms cannot be recommended as a worthwhile mitigation option. [Copyright &y& Elsevier]

Cyriac Tor Ltd is to distribute Metso Outotec slurry pumping solutions in the UK. [ABSTRACT FROM AUTHOR]

The ecological and human health impact of antibiotic use and the related antimicrobial resistance (AMR) in animal husbandry is poorly understood. In many countries, there has been considerable pressure to reduce overall antibiotic use in agriculture or to cease or minimise use of human critical antibiotics. However, a more nuanced approach would consider the differential impact of use of different antibiotic classes; for example, it is not known whether reduced use of bacteriostatic or bacteriolytic classes of antibiotics would be of greater value. We have developed an ordinary differential equation model to investigate the effects of farm practice on the spread and persistence of AMR in the dairy slurry tank environment. We model the chemical fate of bacteriolytic and bacteriostatic antibiotics within the slurry and their effect on a population of bacteria, which are capable of resistance to both types of antibiotic. Through our analysis, we find that changing the rate at which a slurry tank is emptied may delay the proliferation of multidrug-resistant bacteria by up to five years depending on conditions. This finding has implications for farming practice and the policies that influence waste management practices. We also find that, within our model, the development of multidrug resistance is particularly sensitive to the use of bacteriolytic antibiotics, rather than bacteriostatic antibiotics, and this may be cause for controlling the usage of bacteriolytic antibiotics in agriculture.

International and UK government reports have cited antibiotic use as a significant driver of antibiotic resistance (AR) in agricultural environments at the national and global scale. Unmetabolised antibiotics excreted in faeces and urine from livestock receiving antibiotic treatment are frequently highlighted as a selection pressure for resistant bacteria in slurry tanks and fields fertilised with animal husbandry waste. In this way, the application of animal waste on agricultural land represents a perturbation of the soil microbiome. From a human health perspective, crops destined for human consumption could also become contaminated with antibiotic residues and/or with bacteria carrying AR genes. However, assessing the flow of antibiotic resistance within farm environments is challenging due to their complex, multi-compartmental nature. As a result, the resilience of soil microbial communities and the response of the soil resistome to slurry application remain poorly understood.Key aims are to quantify AR within cattle slurry amended soils and to characterise factors which govern AR at the University of Nottingham (UoN) Dairy Farm site over two seasons of slurry application (2017/18). Specific objectives were to determine how antibiotic resistance profiles and community structure of soil bacteria respond to successive slurry applications, to establish a baseline for unamended soils in the same geographical area and to use the real-world data gathered to generate statistical models of AR in slurry amended field soils. By using a combination of classical culture and molecular techniques at the field scale we sought to negate common issues of methodology bias. Over 350 isolates were tested for phenotypic resistance to a range of antibiotics over the study period. Approximately 11% of these isolates were multi-drug resistant, with sub-sets of these isolates displaying resistance to select penicillins, 1st and 3rd generation cephalosporins, phenicols, nitrofurans, and synthetic quinolones. Soil samples were subject to DNA extraction and metagenomic analysis to elucidate microbial community composition and the resistome. Data will be discussed and contextualised within the current understanding of AR in the environment and farm management practices. [ABSTRACT FROM AUTHOR]

Organic fertilizers, such as digestates and manure, are increasingly applied in agricultural systems because of the benefits they provide in terms of plant nutrients and soil quality. However, there are few investigations of N 2 O emissions following digestate application to agricultural soils using process-based models. In this study, we modified the UK-DNDC model to include digestate applications to soils by adding digestate properties to the model and considering the effect of organic fertilizer pH. Using the modified model, N 2 O emissions were simulated from two organic fertilizers (digested food waste and livestock slurry) applied to three farms in the United Kingdom: one growing winter wheat at Wensum (WE) and two grasslands at Pwllpeiran (PW) and North Wyke (NW). The annual cumulative gross (i.e. not excluding control emission) N 2 O emissions were calculated using MATLAB trapezoidal numerical integration. The relative errors of the modeled annual cumulative emissions to the measured emissions ranged from -5.4% to 48%. Two-factor models, including linear, exponential and hyperbola responses, correlating total N loading and soil clay content to calculations of N 2 O emissions and N 2 O emission factors (EFs) were developed for calculations of emission fluxes and EFs. The squares of the correlation coefficients of the measured and two-factor linear modeled emissions were 0.998 and 0.999 for digestate and slurry, respectively, and the corresponding squares of correlation coefficients of the EFs were 0.998 and 0.938. The two-factor linear model also predicted that the EFs increased linearly with decreasing clay content and the maximum EFs for digestate and slurry were 0.95 and 0.76% of total N applied, respectively. This demonstrates that the modified UK&#95;DNDC is a good tool to simulate N 2 O emission from digestate and slurry and to calculate UK EFs using TIER 3 methodology.., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Ralspeed was recently charged with designing a simple and reliable control system for use on the U.K.''s largest slurry tank. The tank which, was designed, manufactured and installed by slurry handling specialist Storth, is 40 m in diameter, almost 6 m high and is capable of holding more than 7 million litres of slurry. To meet these special requirements, Ralspeed designed and built a fully customised control panel. [Copyright &y& Elsevier]