|Solid, Liquid & Gaseous Fuels
|Thermodyne Engineering Systems
|Up to 40 Kg/cm2
|Sugar, Dairy etc.
High pressure boilers (Powertherm) 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 has a vast experience in manufacturing Water Tube Boilers of a wide range of capabilities that suit the customer needs.High Pressure Boilers Working:-
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 vapor pressure exceeds the vapor 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 BoilersNatural 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 Treatment Chemicals:-
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 of High Pressure Boilers:-
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 in the high-temperature zone where the radiation heat transfer takes place between the gases and water. From the 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 the 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.Fuel Used in High Pressure Boilers:
- Rice Husk
- Groundnut shells
- Liquid and Gaseous (such as Light/Heavy Diesel Oils, Natural Gas)
- and several other fuels etc.