Smoke tube boiler

Application area: sawmill, heat contractor, heating station
Power range: 340 bis 2.200 kW
Fuel: wood chips and wood shavings
Water content: off 30 to 60 %

Heating with renewable raw materials is increasingly in demand in the era of the “energy transition”. Wood in the most diverse forms is an alternative energy carrier, especially for municipal and commercial energy providers as well as contractors. Whether in schools, hospitals, hotels, indoor swimming pools, district heating plants, market gardens or in the wood industry - the search for inexpensive and environmentallyfriendly alternatives for the supply of heat is omnipresent.

Task:

The variety of the fuels with regard to water content, grain size, bulk weight, calorific value and ash content necessitates a correspondingly wide range of suitable boiler and combustion systems. The Bioflamm® RK boiler combines the benefits of the proven traversal grate furnaces with the advantages of a smoke tube boiler.
The compact, modular and economical construction enables space-saving installation as well as simple assembly with existing central heating systems. This series was conceived especially for the high requirements in heating plants with local and district heating networks as well as for the high operating times as a base load boiler with fuels that are sometimes demanding and moist.

Technology:

The furnaces from the type series TRF-RK are offered with the counter flow principle for moist fuels with a high ash yield. The generously dimensioned grate areas of the hydraulically driven feed grate and a correspondingly
large combustion chamber volume ensure complete and efficient burning with low flue gas emissions. The graduated and adjustable combustion air supply essentially contributes to high dwell times and optimum combustion. An air-cooled casing around the combustion chamber, with which the radiant heat is removed, enables at the same time the pre-heating of the combustion air. The combustion chamber refractory lining of the double vaulting is available in different qualities for the respective fuel properties. The high chrome content of the alloy used for the cast grate bars contributes to long service lives. A variable grate speed can be adjust by intermittent control, resulting in a largely calm firebed - the prerequisite for an optimum low-pollution combustion process. Access to all relevant parts of the boiler is
ensured by large sized and optimally insulated cleaning and inspection doors. The thick-walled heat exchanger is a triple-pass smoke tube / fire tube boiler. The flame tube is manufactured half-open for optimum burning and a lower overall height. The pressure hull is fitted with two largely dimensioned inspection doors on the front side.

Options:

A pneumatic pressure pulse cleaning system cleans the triple-pass heat exchanger at freely programmable intervals and provides for high boiler efficiency. The removal of ash from the grate is carried out by an automatic ash screw and an undergrate
ash removal system. Regarding the ash containers employed, the customer has the choice from a broad range of standard containers. For fuels that tend to form slag, a flue gas recirculation system controlled according to the combustion chamber temperature is offered for the reduction of the combustion chamber temperature. Various feeding units are available from the Bioflamm® product range for the feeding of
the furnace, from the feed screw to the hydraulic feed piston.

Controller:

Like all Bioflamm® boiler plants the proven PLC controller and combustion optimisation are also available in the Lambdamatic and Optimatic equipment packages for the series TRF-RK. Depending on the supply and furnace temperature, the flue gas temperature, the residual oxygen content in the flue air and the vacuum, the power is regulated by adapting the fuel quantity, the combustion air and the vacuum.
The Easy-Graph remote monitoring system enables the plant user to implement a telephone or web-based visualisation of all plant data, complete data archiving and a simple analysis of the plant function, a graphical display and archiving of operating data and external process optimisation. Buffer management is also available as an extension package

The whole concept:

“Any chain is only as strong, as its weakest link” - the concept of an efficient and reliable wood burning plant doesn’t stop at the boiler. That’s why we offer a complete system, from the fuel discharge and conveying equipment to the flue gas filtering and control of the plant. Our decades of experience and a large number of satisfied customers enable us to develop a suitable plant concept for every customer and their requirements.