Quantification of wastewater sludge dewatering.

Quantification and comparison of the dewatering characteristics of fifteen sewage sludges from a range of digestion scenarios are described. The method proposed uses laboratory dewatering measurements and integrity analysis of the extracted material properties. These properties were used as inputs into a model of filtration, the output of which provides the dewatering comparison. This method is shown to be necessary for quantification and comparison of dewaterability as the permeability and compressibility of the sludges varies by up to ten orders of magnitude in the range of solids concentration of interest to industry. This causes a high sensitivity of the dewaterability comparison to the starting concentration of laboratory tests, thus simple dewaterability comparison based on parameters such as the specific resistance to filtration is difficult. The new approach is demonstrated to be robust relative to traditional methods such as specific resistance to filtration analysis and has an in-built integrity check. Comparison of the quantified dewaterability of the fifteen sludges to the relative volatile solids content showed a very strong correlation in the volatile solids range from 40 to 80%. The data indicate that the volatile solids parameter is a strong indicator of the dewatering behaviour of sewage sludges.

The Journal of James Wilson: An Insight into Life in North East Scotland Toward the End of the Nineteenth Century .

In the nineteenth century many farmers kept a diary of the farming year to record such features as the weather, crop yields, animal husbandry, and prices. Research into church and people in the parishes of Fordyce and Portsoy in North East Scotland led to the discovery of a four-volume journal kept by James Wilson, a farmer in the Banffshire Parish of Deskford between 1879 and 1892. This journal provides a detailed picture of many aspects of rural life including farming, family, neighbors, religion, friends, and entertainment. Moreover, Wilson wrote poetry and kept a record of his lectures given to the local Mutual Improvement Associations. Taken together, the journal, poems, and lectures provide a significant body of literature giving insights into rural society. The journal also covers an important period in farming at the nexus between a time of "high farming" and the agricultural depression of the late nineteenth century.

Combination of ferric and MIEX for the treatment of a humic rich water.

Seasonal periods of high rainfall have been shown to cause elevated natural organic matter (NOM) loadings at treatment works. These high levels lead to difficulties in removing sufficient NOM to meet trihalomethane (THM) standards, and hence better alternative treatments are required. Here the removal of NOM was investigated by a new ion exchange process (MIEX) using both bulk and fractionated NOM. Initial results showed that in excess of 80% of the raw water dissolved organic carbon (DOC) and greater than 85% of the UV absorbance from the bulk raw water could be removed by the use of MIEX alone. It was also seen that the removal of the more recalcitrant isolated fractions was increased. When MIEX was combined with a significantly reduced dose of coagulant a slight improvement on the overall DOC and UV removals was observed, however a significant decrease in the amount of THM formation potential (THMFP) in the final water was seen. This combined with the reduction in coagulant would imply a more efficient process during the times when the water becomes increasingly difficult to treat.

A model for predicting dissolved organic carbon distribution in a reservoir water using fluorescence spectroscopy.

A number of water treatment works (WTW) in the north of England (UK) have experienced problems in reducing the dissolved organic carbon (DOC) present in the water to a sufficiently low level. The problems are experienced in autumn/winter when the colour increases and the coagulant dose at the WTW needs to be increased in order to achieve sufficient colour removal. However, the DOC content of the water varies little throughout the year. To investigate this further, the water was fractionated using resin adsorption techniques into its hydrophobic (fulvic and humic acid fractions) and hydrophilic (acid and non-acid fractions) components. The fractionation process yields useful information on the changing concentration of each fraction but is time consuming and labour intensive. Here, a method of rapidly determining fraction concentration was developed using fluorescence spectroscopy. The model created used synchronous spectra of fractionated material compared against bulk water spectra and predicted the fraction concentrations to within 10% for a specific water. The model was unable to predict fraction concentrations for waters from a different watershed.