Porous candle filters and monolithic ceramic elements that clean exhaust gas or recover its heat, as drop-in replacements.
Clean the gas while it is still hot, or take its heat before it leaves.
Both jobs need ceramic that stays open and stays whole.
Ceramic candle filters and recuperator elements work at high temperature when the ceramic is chosen for the gas and the porosity is controlled. A hot gas filter needs fine, interconnected pores so the gas passes through the wall while dust and ash stay on the surface; a recuperator element needs a large surface per volume to transfer heat. Blasch makes both as monolithic, drop-in replaceable elements, cast or extruded in alumina, mullite, cordierite and other heat and chemical resistant compositions.
Hot gas filtration removes dust before the gas cools, for example after gasification or incineration, where cooling first would waste heat or let condensates form. The filter element is a porous ceramic body, often a candle closed at one end. Gas flows through the wall, and particles stay outside.
Blasch filters have a controlled, tight and interconnected porosity. Dust, ash and products of combustion do not enter the structure, so the element does not plug from inside and cleaning stays limited to the surface. The Blasch casting process produces a very even pore structure, with pore sizes of a few micrometers.
A ceramic filter is only as good as its pores: once dust gets into the wall instead of staying on it, no cleaning cycle brings the element back.
Each element is designed for one unit, from its dimensions, temperatures and gas.
Porous candle filters that separate dust and ash from exhaust gas at temperature, with surface cleaning only.
Monolithic ceramic elements that recover heat from exhaust gas with a large heat transfer area per volume.
Monolithic media can raise the flow through existing hot gas scrubbers and regenerative thermal oxidizers, or reduce the media volume of new ones.
Elements are made to replace the existing ones in place, without changes to the housing.
The Blasch casting process shapes features that otherwise need machining or extra parts:
Alumina, mullite and cordierite are the usual compositions, chosen for chemical, abrasion and heat resistance. Cordierite brings low thermal expansion and thermal shock resistance at a lower cost and is stable up to about 1,000 °C. More on cordierite and alumina.
Blasch engineers work with OEMs and single plants on pressure drop, energy use, filter performance and replacement cost. Hot gas filters run in power generation and in industrial process heating.
Where heat is stored in a packed bed rather than recovered through a wall, see thermal storage media. Both belong to the Blasch self-supporting ceramic structures and ceramics for hot gas.
It depends on the composition. Cordierite is stable up to about 1,000 °C, alumina and mullite go higher. The grade is chosen for the gas temperature and chemistry.
The tight, interconnected porosity keeps dust and ash on the surface of the element, which limits plugging and cleaning effort.
Yes, as drop-in elements made to the dimensions of the existing ones. A drawing is not required, dimensions and operating data are enough.
Send the element dimensions, the gas temperature and what the gas carries. A Blasch engineer proposes the composition and the design.
