Waste Steam Research Articles

98/00678 Study on the dynamic characteristics of the double-effect absorption refrigerator driven by waste steam

98/00678 Study on the dynamic characteristics of the double-effect absorption refrigerator driven by waste steam

Study on the Start-Up Characteristics of a Double-Effect Absorption Refrigerator Driven by Waste Steam.

Absorption refrigerator can be driven by waste heat. In particular, the double-effect type absorption refrigerator, which is highly efficient, is drawing a great deal of attention as a waste heat recovery system. This research refers to the double-effect absorption refrigerator driven by steam, assuming waste heat from the fuel cells is applied. In the start up of the double-effect absorption refrigerator, the solution temperature is almost equal to the temperature of the air. Due to the large temperature difference between the solution and the heat sources, the solution is over heated. In the worst case, it will be crystallized. Additionally, some solution is circulated due to the existence of a pressure difference between the heat exchangers. If the solution pump is started before and adequate pressure difference is obtained, the absorption refrigerator cannot be started normally. To investigate these problems, the simulation model is constructed. An experiment is conducted to investigate the performance of this model. As a result, the validity of this model is confirmed and the detailed start-up characteristics are clarified.

Study on the Dynamic Characteristics of the Double-Effect Absorption Refrigerator Driven by Waste Steam.

Study on the Dynamic Characteristics of the Double-Effect Absorption Refrigerator Driven by Waste Steam.

Vacuum desalination for water purification using waste heat

Vacuum desalination is a process by which water is vaporized at a lower temperature when subjected to vacuum pressure. The heat energy requirement for desalination using a distillation process can be brought down by reducing the boiling temperature. The boiling temperature of seawater can be lowered to as low as 400°C by the creation of a vacuum. Using waste heat from a steam turbine, a pilot study was conducted in the laboratory to investigate the feasibility of using a vacuum desalination process for water supply. The treatment system is designed to minimize the heat requirement. Initially, the seawater is converted to a wet steam in a saturated vapour heater. This vapour heater receives heat from the superheated steam which is due for condensation. The dry component of the wet steam is heated to superheated condition by a superheated vapour heater. This superheated vapour heater receives heat from the waste heat from a steam turbine. Superheated vapour is used to covert incoming seawater to wet steam and then be condensed as the product of the system for potable use. The investigation shows that a vacuum desalination system using turbine exhaust waste steam is possible and has several advantages. Seawater can be boiled at a lower temperature and thus save in energy consumption. Based on experimental results, water boils at 40–90°C at the corresponding vacuum pressure of 0.1–0.7 bar, respectively. The consumption of heat from the waste steam is minimized as the superheated vapour is used to heat the influent seawater. Most of the heat from the waste heat is required to compensate for the heat losses in the system. The energy efficiency of the system depends very much on decreasing the heat losses from the system. It is possible to use nonconventional energy sources such as lower pressure waste steam for vacuum desalination. Hard scale formation in the system can be minimized as scale forming is the major problem in a high temperature distillation process. The qualities of distillates are excellent.

Continuous solidification/stabilization processing of hazardous wastes through polymeric microencapsulation

This paper reports that the continuous solidification/stabilization of a simulated aqueous hazardous waste steam through microencapsulation in a polyester matrix was evaluated in a static mixer/reactor and found to be feasible. For the emulsion formation step, the Sauter mean droplet size of the emulsion formed was found to vary with the stream total flow rate to the -0.87 power, the number of mixing elements to the -0.63 power, and the volume fraction of waste to the 0.2 power. Next, numerical simulation of the polymerization reaction step for the conditions investigated predicted that the degree of polymerization occurring inside the mixer/reactor was only on the order of a safe and desirable 0.2% of the total conversion, thus ensuring the absence of any premature gelling within the mixer/reactor; also, this resulted in only a negligible fluid temperature rise, these being verified by experimental observations and measurements. On these bases, exothermicity and solidification of the stream inside the mixer/reactor are hence not expected to be processing problems.

Vacuum desalination using waste heat from a steam turbine

The process reported is known as vacuum desalination. This technique takes advantage of the drop in boiling point of sea water if pressure is reduced. By doing so, the temperature of a turbine exhaust steam is sufficiently high to cause boiling of sea water at the pressure of about 10 kPa. The system comprises of a saturated vapour heater and superheated vapour heater. Initially, the sea water is converted to a wet steam in the saturated vapour heater after receiving heat from a superheated steam which is due for condensation. The dry component of the wet steam is then channelled to the superheated vapour heater and is heated to superheated condition by the turbine waste steam. The system is designed in such a way that heat from the superheated steam is reused for heating up the incoming sea water in the saturated vapour heater. The consumption of heat from the turbine waste steam is kept to a minimum and most of which is to compensate for heat losses in the system. In the saturated vapour heater, the superheated steam after rejecting its latent heat to the incoming sea water is condensed and is pumped out from the system by a positive displacement pump.

Waste Heat Recovery and Steam Locomotive Design

Waste Heat Recovery and Steam Locomotive Design

Parameters analysis on organic rankine cycle energy recovery system

A systematic algorithm of parameters analysis on an Organic Rankine Cycle (ORC) energy recovery system has been proposed. It includes thermodynamic analysis, economic evaluation and sensitivity analysis, and economical design parameters study. The cases studied indicate that the effects of the design parameters ( T H, T L, T 1, and E g) on the system's economic feasibility are very significant, and there is an economical combination of those parameters. Annual operation hours, electricity unit cost, and equipment manufactured cost are also important parameters to the integrated benefit of an ORC recovery system. Moreover, it shows that the recovery of low temperature, gas phase waste heat by an ORC system is economically unattractive; however, the recovery of low-pressure waste steam by an ORC system has been shown to be a high potential for moderate capacity plants.

ＴＭＰ廃蒸気からの熱回収

In this paper, a method of heat recovery to produce clean steam used as a general heat source from TMP waste steam is described and assessed whether investment in heat recovery system is feasible.

Bound Glass in Shredded Municipal Solid Waste

The binding and trapping of glass and organics that occurs during the shredding of municipal solid waste (MSW) is examined experimentally. Such glass is called bound glass. This process produces feed which detrimentally effects air classifier production of refuse derived fuel (RDF). Glass contaminated RDF causes excessive slagging on incinerator walls and abrasion of mechanical parts. Results indicate that the glass prticle size distribution produced by the shredder and the moisture content in the waste steam effect bound glass amounts. Further, bound glass increases with moisture content and increases with decreasing particle size. Dry waste streams and shredders which produce large glass particles are suggested to produce better feeds for air classifiers, and consequentially better RDF.

Ejector-compression systems for cooling: Utilising low grade waste heat

The ejector-compression system is an attractive means of cooling, using low grade thermal energy in the temperature range of 70–90°C as heat input to the cycle. This energy is available from flat plate solar collectors, waste steam, exhaust from automobiles and flue gases etc. The effects on mass flow ratio of motive vapour to evaporator vapour, condenser heat capacity and coefficient of performance, have been studied as a function of boiler temperature by varying the evaporator and condenser temperatures for promising refrigerants such as R-11 and R-113.

Anaerobic Biological Decomposition of Malodorous Compounds in Kraft Pulping Wastewater

The capability and performance of anaerobic biological decomposition of malodorous compounds in kraft pulping wastewater were studied. The experimental apparatus used in this investigation was a bench-scale semi-batch anaerobic contact process of which a digester vessel was operated in regular sequence as a stirred digester and a stationary sedimentation tank. The results obtained from this experiment revealed that digesting anaerobic sludge could convert dimethyl disulfide (DMDS) to methyl mercaptan (MM) and that MM was partially decomposed into H2S. To maintain this anaerobic biodegradation of sulfur-containing malodorous compounds, the concentration of H2S in digester mixed liquor was required to be kept below about 5 mg/L. The conditions of temperature of 50 °C and pH of 6.5 were most suitable for the methane fermentation of the kraft pulping waste steam drainage and for the removal of the malodorous compounds. Scrubbing of the digester head space gas with the solution of sodium hydroxide removed not only H2S but also MM, so that a high removal rate of DMDS and MM was achieved. Unfortunately, dimethyl sulfide (DMS) could not be decomposed biologically, but it could be removed easily with a simple air stripping process. From these results, an effective process combined with anaerobic digestion for the economical prevention of odor nuisance was proposed.

Prediction of the effects of steam addition on performance of gas turbines with fixed-bed regenerators

The use of waste steam in gas turbine plants has been proposed. The complete gas turbine unit including the counterflow regenerative heat exchanger has been simulated on a digital computer. The improvement in cycle thermal efficiency by the use of waste steam is predicted.

Matrix temperature control by recirculation in thermal regenerators using waste steam

Addition of steam to combustion air in thermal regenerator, though considerably increases their thermal ratios also lowers the matrix surface temperatures. Recirculation of a part of combustion air is proposed to control the matrix temperature in regenerators employing steam injection. It has been predicted that with 20% recirculation the minimum matrix temperature is increased by about 50°C. Though there is a little drop in the regenerator thermal ratios, which are already substantially increased by steam injection.

Condensation of steam by air cooling using fan-type coolers

1. When waste steam at a pressure of Pabs=3 kg/cm2, which cannot be used, has to be cooled so that the condensate can be returned to a thermal power station or boiler, it is preferable to use air cooling by means of standard fan coolers, working with atmospheric air, supplied by an axial fan. 2. Compared with the widely used method of cooling in heat exchangers, the use of air cooling in fan coolers gives a considerable saving in operating costs. 3. Air cooling by means of standard fan coolers can also be employed for the cooling or condensation of light petroleum products.

THE BLEEDER TURBINE AS A COAL CONSERVATOR

Journal of the American Society for Naval EngineersVolume 35, Issue 1 p. 161-167 THE BLEEDER TURBINE AS A COAL CONSERVATOR Excess Power as a “By-Product” of Waste Steam J. L. Moore., J. L. Moore.Search for more papers by this author J. L. Moore., J. L. Moore.Search for more papers by this author First published: February 1923 https://doi.org/10.1111/j.1559-3584.1923.tb00651.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume35, Issue1February 1923Pages 161-167 RelatedInformation

Utilization of waste steam at the Milwaukee refuse incinerator

Utilization of waste steam at the Milwaukee refuse incinerator