Establishment of Periodicity of Water Quality Monitoring with Due Regard for Measurement Inaccuracy

Summary

The periodical monitoring of quality of water with changeable characteristics is connected with sampling errors. Methods of accounting of these errors together with characteristics of measurement inaccuracy of polluting substances concentration for assessment of the risk of false conclusions about water compliance (or non-compliance) with specified requirements are offered. It is reasonable to establish the periodicity of measurements from the calculation of proportionality of sampling errors and meteorological inaccuracy specified by the certified measuring technique. The table of optimal periodicity of measurements depending on maximum permissible concentration of a polluting substance and changeability of its concentration in a water body as well as the scheme of prediction of water quality with a specified confidence level are offered for practical application.

Key words

water supply , reliability , pollution , water disposal , standard , quality control , periodicity , selection , samples , measurement inaccuracy , concentration

Test of Technology of Galvanochemical Wastewater Treatment for Arsenic Compounds

Summary

The substantiation of perspectivity of application of the galvanochemical method of arsenic removal from wastewater is made. Results of the laboratory study of efficiency of galvanochemical treatment of arsenic-containing model solutions and natural wastewater of an intergrated copper-sulphur plant are presented. It is shown, that application of this technology makes it possible to remove arsenic up to values of Maximum Permissible Concentration (MPC) for water objects. Efficiency and arsenic removal rate depend insignificantly on an initial pH value (in the range of 1,5–9,5). Duration of the galvanochemical treatment ensuring the obtaining of arsenic residual concentrations on a level with MPC depends on its initial concentration in media treated and on a galvanic couple used. The process of arsenic removal progresses with a higher rate when an «iron – copper» galvanic couple is used. When an «iron – crushed coke» galvanic couple is used the duration of treatment necessary for obtaining the arsenic concentration on a level with MPC increases in 2–3 times. Basic flow charts of the galvanochemical treatment of wastewater depending on the initial concentration of arsenic are offered.

Key words

wastewater , arsenic , reagent methods , galvanochemical treatment , toxicity

An Innovative Approach to the Operation of Organization's Computer Facilities and Office Appliances

Summary

Challenges, tasks and approaches in assuring uninterrupted operation of computer facilities and office appliances at one of the biggest public utility in Russia – SUE St. Petersburg Vodokanal are given. Measures, stages of development and results of introducing special means that provide for automatic acquisition, storage, record and analysis of information on organization's IT-infrastructure objects are discussed. The results of introducing HP OpenView Service Desk, software product to computerize the operation of IT support services operation are given. The chosen direction of organization's IT infrastructure development provides for improving the quality of services rendered to the user at maintaining an optimal level of operation expenses.

Key words

information technologies , computer facilities , office appliances , IT-infrastructure , IT Infrastructure Library , software