High Pressure Boilers – PowerthermPowertherm or high pressure boilers are mostly water tube boilers in which water is on the tube side while flue gases flow across the tubes thereby transferring heat from flue gases to water using cross flow heat transfer.
Thermodyne Engineering Systems has a vast experience in manufacturing Water Tube Boilers of a wide range of capacity that suits the customer needs.
Before converting to steam, water circulates multiple times from shell (water drum) to water tubes and then back to shell. During the circulation, the temperature of water increases as it comes in indirect contact with flue gases that transfer heat through tubes. Water circulation continues until it’s vapour pressure exceeds the vapour pressure of steam at the top of the drum.At this pressure, water gets converted to saturated steam.
Overall, Circulation Ratio is an important factor in designing of water tube boilers. Based on circulation there are 2 basic designs of water tube boilers: Natural Circulation Boilers and Forced Circulation Boilers
Natural Circulation Boilers are the type of boilers where water circulates naturally that is due to the density difference. The difference in density is created with the difference in temperature of cold and hot water. Circulation ratio is an important factor in designing of natural circulation boilers so as to prevent the overheating or bursting of tubes.
Water Circulation in Forced Circulation Boilers, on the other hand, does not depend upon the difference in densities but is dependent upon the secondary pump which is installed after the feedwater pump (primary pump) that forcefully increases or decreases the circulation ratio depending on the design and safety requirements.
Construction and Operation:
The basic D-Type design of our water tube boilers includes a Furnace enclosed by a set of water tubes which is called a membrane. The furnace is a part where combustion of fuel takes place. The fuel feeding in such boilers is mostly done automatically either through drum feeders, rotary feeders or screw feeders in case of solid fuels and burners in case of liquid or gaseous fuels.
The furnace is the high-temperature zone where the radiation heat transfer takes place between the gases and water. From radiation zone, flue gases enter the convection zone. It consists of convection tubes which are stacked vertically closer to each other, welded at the top and bottom ends to both the water and steam drums respectively. Flue gases in convection zone travel at high velocity across the convective tubes.
Baffles are sometimes provided to increase the turbulence. Because of high velocity of flue gases, convective heat transfer between the flue gases and water increases thereby increasing the overall heat transfer rate.
Water drum is placed at the bottom of the boiler while the steam drum is placed at the top.
Water feeding is done through the high-pressure pump to the steam drum which has a clear demarcation of water and steam space. The set of tubes which are in contact with a high temperature of flue gases act as riser tubes to carry steam to steam drum while the tubes which are in contact with low-temperature act as a downcomer tubes to carry water to the water drum. This upward and downward flow of water and steam due to density difference in the tubes helps to maintain the circulation ratio of a boiler.
Depending on the steam pressure and temperature requirement, the superheaters can be installed either between the radiation and convection zone or after the convection zone. Other accessories like Economiser and Air-pre heater are also installed in line with the boiler so as to extract the waste heat leaving the boiler and thereby increasing the overall efficiency of a boiler.
- The heat of combustion is used to lots of efficiently by the use of small diameter tubes in big numbers.
- To avoid big resistance to the flow of water, Powertherm boilers have a parallel set of an arrangement of tubes.
- The Steam boiler parts are usually organized horizontally, giving larger accessibility and operational convenience.
- All the elements are uniformly heated, so the danger of warming is reduced. besides thermal stress drawback is avoided.
- The tendency of scale formation is eliminated thanks to the high speed of water through the boiler tubes.
High Pressure Boiler (Powertherm) are available in capacities from 10 TPH to 25 TPH.
Fuel Used in High Pressure Boilers:
- Rice Husk
- Groundnut shells
- Liquid and Gasesous (such as Light/Heavy Diesel Oils, Natural Gas)
- and several other fuels etc.
High Pressure Boiler Product Videos:
Manufactured by: Thermodyne
Product ID: TB0001HPB4.9 based on High Pressure Boilers for all industrial steam process applications reviews