Chemical Water Purification Research Articles

INCREASE OF ECOLOGICAL EFFECTIVENESS OF COMPLEX HEAT-RECOVERY SYSTEMS FOR BOILER PLANTS

It is revealed that the humidifying of blown air in complex heat recovery systems of gas-fired boiler plants provides the significant reduction in the concentration of nitrogen oxides in exhaust-gases due to the suppression of their formation in the boiler furnace when moisture is introduced with this air. 
 Problems of environmental protection and energy-saving became priority in world practice. The main directions of deciding these pressing problems in municipal heat-power engineering is to improve the environmental indicators of heating boiler plants and increase the efficiency of using fuel in them through the use of technologies for deep recovery of the exhaust-gases heat. The relevance of scientific problems in these directions is increasing due to the steady increase in the fuel-energy costs and the strengthening of requirements to reducing environmental pollution.
 When using these technologies of deep heat-recovery of exhaust-gases, the condensation mode of the heat-recovery equipment is realized, when, apart from to the so-called clear heat of these gases, the latent heat of condensation of the water vapor contained in them is also used. The condensation mode implementation also improves the ecological indicators of the boiler due to the reduction of fuel consumption and the dissolution in the resulting condensate of a part of harmful emissions formed during its combustion.
 The use of modern heat-recovery technologies for the gasfired boiler plants with complex use of recovered heat for the preheating of boiler water, water of the chemical waterpurification system and blowing air makes it possible to reduce fuel consumption in the boiler and, accordingly, its harmful emissions by 8...12 %.
 Humidification of the blowing air through the use of the recovery heat also provides a reduction of nitrogen oxides emissions to 60 % by suppressing their formation in the boiler combustion chamber.

Comparative Performance Analysis of Rectangular Shaped Solar Collector Basin with Reflector and Photo Catalyst

One of the basic requirements for every human being is the availability of clean drinking water, but about 1.1 billion people in the world lacked pure drinking water. Thfere several types of water purification processes used worldwide such as filtration, reverse osmosis, ultraviolet radiation, carbon absorption, but distillation and boiling is considered to be the most reliable among these process. In areas where water resources or tap water is not suitable for drinking without boiling or chemical treatment Water purification, such as distillation, plays an important role in providing clean drinking water. Distillation is the common method usually seen in nature in which the water on earth is heated by sun and then converted into a vapor (evaporation) and rises, leaving behind contaminants, to form clouds. The vapor converts back to water after it cools when the temperature in the upper atmosphere drops. Water is essential for life. The origin and continuance of mankind is based on water. Developing countries face a significant problem in the supply of drinking water. With the increasing population and industrial growth and agricultural activities causes depletion of many fresh water resources due to rapid increase in need for energy and to overcome environmental concerns much attention is focused on renewable energy resources. Solar distillation is one of the non-conventional methods to desalinate brackish water or sea water. This work focuses on an experimental investigation by comparing the performance of two solar stills such as rectangular shape and basin shape solar still, with photo catalyst and reflector base solar still. The comparative performance study is analyzed for the same weather conditions with different design parameters and some important conclusions were assigned.

IMPROVEMENT OF COMPLEX HEAT-RECOVERY SYSTEMS FOR GAS-FIRED BOILER UNITS

The calculation and analysis of the complex heat-recovery system for heating by warmth of exhaust-gases from a boiler unit several heattransfer agents for the needs of the boiler house, namely, return heat-network water, combustion air and raw water for chemical water-purification system have been carried out. Results of researches have confirmed high efficiency of the offered technical solution.

Research of sorption processes using chemical water purification sludge for nitrogen and sulfur oxides contained in smoke gases emitted from a thermal power station

The possibility of the use of chemical water purification sludge of the Kazan Thermal Power Plant-1 as a sorbent for treatment of smoke gases is considered. The sorption capacity was studied, the sorption isotherm was obtained, and an adsorber with a fixed layer of sludge and acting periodically was analyzed.

C143 界面の光学的特性を用いた固気液三相流の空間速度分布計測(OS-9:沸騰・凝縮伝熱および混相流の最近の展開(2))

Bubbly flows are found in a lot of industrial fields such as power and chemical plants and water purification system. PIV is useful tool to investigate the bubble motion and flow structure in the liquid phase simultaneously. In the present study, we have developed velocity measurement system of solid-gas-liquid three phase flow by phase discrimination using interferometric imaging of scattered light. We applied this system to microbubble flow, measuring area was about 9.6mm×8.0mm and we could discriminate the bubbles from the solid tracers within a range of ±1mm from the focal plane. Moreover, bubbles going up and solid tracers settling out were captured. From these results, it is concluded that this system can be applied successfully to measurement of the velocity distribution of three phase flows.

Study of the sorption of oil products of power station wastewater modified with a TPP illuminator slurry

We examine the possibility of using a chemical water purification (CWP) slurry from the HS-1 as a sorbent for purifying TPP wastewater of oil products. We propose ways to increase the absorption capacity of the slurry. We present the results of studying the modified sorbent.

Review of Studies on Gas-Liquid Two-Phase Flow and Mixture Systems

Gas-liquid two-phase flow and mixture systems are encountered in various industrial apparatuses and applications. The systems can be categorized as the following four : (a) the systems with heat transfer and with the flow of both gas and liquid, like boiling two-phase flow in heat exchangers, (b) the systems without heat transfer but with the flow of both gas and liquid, like adiabatic two-phase flow in oil pipe line systems, (c) the systems with heat transfer but without the flow of one of gas and liquid, like pool boiling, and (d) the systems without heat transfer and without the flow of one of gas and liquid, like aeration in chemical reaction and water purification systems. Of these, the first two categories are mainly dealt here and the relating papers reported in “Transactions of the Japan Society of Mechanical Engineers, Series B” and in “JSME International Journal, Series B” since January 2004 to August 2006 are reviewed to seek the future studies in the field of the gas-liquid two-phase flow and mixture systems.

Use of Chemical Water Purification Waste from Power Plants and Mines in Ceramic Production

The possibility of using waste generated by chemical purification of sewage waters from power plants and mines is determined. The main physical properties of the materials obtained are described.

Quality of water used for haemodialysis: bacteriological and chemical parameters.

The bacterial and chemical contamination of dialysate fluids are important problems in haemodialysis therapy and may be caused by the water used for dialysate preparation. We performed a survey of the microbiological and chemical quality of the water used in seven dialysis wards. Special attention was paid to the effects of each water treatment step, for example ion exchange, reverse osmosis and UV disinfection, on the number of bacteria (measured as colony forming units, CFU), the amount of endotoxin (endotoxin units, EU) and various chemical parameters, the main focus being on calcium, magnesium, sulphate, aluminium and heavy metals. CFU values exceeding the European Pharmacopeia value, determined at an incubation temperature of 22 degrees C, were found in the samples of raw water (20.0%, n=25), after ion exchange (66.7%, n=12), after reverse osmosis (33.3%, n=18) and also in samples of the dialysis water taken at the inlets (12.5%, n=40) and outlets (50.0%, n=18) of the machines. Whereas all raw water samples from the wards showed high mean values for endotoxin (0.56-9.10 EU/ml) and the endotoxin levels were often enhanced after ion exchange (0.13- >9.49 EU/ml), treatment by reverse osmosis led to a satisfactory decrease in endotoxin in all samples (<0.03 EU/ml). Sufficient reductions in calcium, magnesium and sulphate could only be achieved by the combined application of ion exchange and reverse osmosis. Mercury contamination was observed in the samples after ion exchange at three treatment plants, this was possibly caused by polluted regenerants. Increased amounts of aluminium, copper and zinc were found in water samples from different sites in the treatment systems and were caused by materials in contact with the water. A sufficient chemical water purification treatment system should consist of ion exchange and reverse osmosis. Attention has to be paid to the suitability of materials in contact with the water and of the chemicals used, for example regenerants or corrosion inhibitors. From the microbiological point of view, a safety UV disinfection step in the water-treatment system is favourable. To avoid bacterial recontamination periodic cleaning and disinfecting of the water-treatment and distribution systems, as well as the dialysis machine are essential. There is the need for complete guidelines regarding dialysis water that include all relevant chemical and microbiological parameters. Based on this standard, periodic examination of the water after each treatment step has to be performed.