A coating for equipment transported at minus temperatures

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 3, pp. 33, March, 1988.     

Dynamics of gleyzation-mediated leaching of radiostrontium from soils

Leaching of radiostrontium from soil under gleyzation is studied with a laboratory setup allowing controlled long-term percolation of the liquid phase through a soil sample and collection of mobile soluble and colloid species at the outlet. Introduction of a nutrient substrate for the growth of microorganisms promoting gleyzation enhances the leaching of radiostrontium from waterlogged soil. The results suggest joint solubilization of the macrocomponents of the clay-humus complex of the soil and associated radiostrontium under gleyzation. Data on the dynamic leaching and distribution coefficients show that, in the stagnant water regime, remobilization of strontium is less intensive than in the percolation mode. The gleyzation-mediated leaching of radiostrontium is suppressed after 2–2.5 months, which can be attributed to the inhibiting effect of Fe(II) accumulated in the system.     

Efficiency of ultra-wideband quasi-radio signal’s frequency estimation

Synthesis and analysis of maximum likelihood algorithms for estimating frequency of ultra-wideband quasi-radio signal with unknown parameters and duration of several periods or a fraction of period of harmonic oscillation are conducted. Dispersions of the synthesized estimates are obtained.     

Experience gained from the development and results from tests of the equipment of the Kalinin NPP Unit 4 regeneration and intermediate steam separation and reheating system

The equipment of the Kalinin NPP Unit 4 regeneration, intermediate separation, and steam reheating (ISSR) systems is described and the results of their static and dynamic tests are presented. It was shown from an analysis of test results that the equipment of the regeneration and ISSR systems produce the design thermal and hydraulic characteristics in static and dynamic modes of its operation. Specialists of the Central boiler-Turbine Institute Research and Production Association have developed procedures and computer programs for calculating the system of direct-contact horizontal low-pressure heaters (connected according to the gravity circuit arrangement jointly with the second-stage electrically-driven condensate pumps) and the ISSR system, the results of which are in satisfactory agreement with experimental data. The drawbacks of the layout solutions due to which cavitation failure of the pumps may occur are considered. Technical solutions aimed at securing stable operation of the equipment of regeneration and ISSR systems are proposed. The process arrangement for heating the chamber-type high-pressure heaters adopted at the Kalinin NPP is analyzed. The version of this circuit developed at the Central Boiler-Turbine Institute Research and Production Association that allows the heating rate equal to 1°C/min to be obtained is proposed.     

Analysis and selection of high pressure heaters design for a new generation of NPP with BN-1200 reactor plant

In the development of advanced high-power steam-turbine plants (STP), special attention is placed on the design of reliable and economical high-pressure heater (HPH) capable to maintain the specified thermal hydraulic performance during the entire service life. Comparative analysis of the known designs of HPH, such as the spiral-collector HPH, the collector-coiled HPH, the collector-platen HPH, modular HPH, and the chamber HPH, was carried out. The advantages and disadvantages of each design were pointed. For better comparison, the heaters are separated into two groups—horizontal and vertical ones. The weight and dimension characteristics, the materials and features of the basic elements, and operating features of variety HPH are presented. At operating the spiral-collector HPH used in the majority of regenerative schemes of high-pressure STP of thermal and nuclear power plants, the disadvantages reducing the economy and reliability of their operation were revealed. The recommendations directed to the reliability growth of HPH, the decrease of subcooling the feed water, the increase of compactness are stated. Some of these were developed by the specialists of OAO NPO TsKTI and are successfully implemented on the thermal power plants and nuclear power plants. Technical solutions to reduce the cost of regeneration system and the weight of chamber HPH, reduce the thickness of the tube plate of HPH, and reliability assurance of the cooler of steam and condensate built in the HPH casing under all operating conditions were proposed. Three types of feed water chambers for vertical and horizontal chamber HPH are considered in detail, the constructive solutions that have been implemented in HPH of the regeneration system of turbines of 1000 and 1200 MW capacity with water-moderated water-cooled power reactor (WMWCPR) are described. The optimal design of HPH for the regeneration system of high-pressure turbine plant with BN-1200 reactor was selected.     

Development of technical solutions for securing stable operation of the intermediate separation and steam reheating system for the K-1000-60/3000 turbine unit

The intermediate separation and steam reheating system and its equipment are described. Problems concerned with the presence of condensate in the stack??s lower chamber and in the removing chamber, with cavitation failure of the separated moisture pumps, with misalignment of heating steam flowrates, with unstable draining of heating steam condensate, with occurrence of self oscillations, etc. are considered. A procedure for determining the level in removing heating steam condensate from steam reheater elements is proposed. Technical solutions for ensuring stable operation of the intermediate separation and steam reheating system and for achieving smaller misalignment between the apparatuses are developed.