Pyrolysis

"Commercial... applications of pyrolysis have been to produce... a eous fuel... or a char... Liquids... directly are unsuitable... as fuels... Some... downstream operations would be required... Nevertheless, low-temperature s can be refined... into or ."

"Possibly, future events on the world energy scene will revive interest... Pyrolysis offers... simplicity of process and equipment design relative to gasification and hydroliquification. ...[But] competing technologies usually provide high yields of a single type... gas, liquid or solid... which may offset the added complexity and cost..."

"[R]ules change when an external supply of is... available. Hydropyrolysis, i.e. pyrolizing coal in a hydrogen atmosphere, increases the yields of liquids and gases... [H]ydrogen... stabilizes radicals by hydrogen capping before... termination by recombination reactions that... lead to char... Despite this advantage... hydropyrolysis has never been commercialized."

"[S]tories... about "free oil" from coal pyrolysis, often in reference to a low-temperature ... by ... [≈]80 years ago. Many... accompanied by... conspiracy theories... The , and similar carbonization processes... produce a liquid. Presumably, a... clever accountant could figure out how this... could be "free," provided... markets existed for... large amounts of char and gas produced at the same time, and... could be sold... high enough to compensate for giving away the liquid. Then there's the cost of refining the low-temperature into specification-grade marketable fuel..."

"Often... terms carbonization and pyrolysis are used almost interchangeably. Pyrolysis has the broader meaning: breaking... molecules by... heat or thermal energy. ...[P]yrolysis ...could be run to make gases and liquids rather than solids as the primary product. ... narrowly defined, refers to conversion of a starting material into carbon, or a carbon-rich solid. ...[One can] pyrolyze a hydrocarbon feedstock for the purpose of carbonization, but carbonization is not... pyrolysis by another name. Carbonization can be effected without heat as... primary driving force... Carbonization driven by thermal energy usually requires >500°C."

"Pyrolysis of an oil product or natural gas leads to thermal blacks. ...Acetylene black is made by of acetylene. ...[P]reheated to 800°C ...acetylene is introduced and... because the pyrolysis is exothermic, the temperature... reaches ~2500°C. formation takes place... [800°C-~]2000°C. ...2000-2500°C induces partial of the carbon black. Due to... partial graphitic nature, acelylene blacks have... applications where good [electrical and thermal] conductivity... or... very low chemical reactivity is desirable."

"Almost all pyrolysis reactions are endothermic because they involve breaking bonds in stable compounds."

"Pyrolysis of fossil or s... is... accompanied by char formation. In some cases, this is the point... being an example. ...[I]f pyrolysis were ...done to make gaseous or liquid fuels, and no... market existed for the char, it would be possible to... bury the char... [which] would sequester carbon..."

"[P]yrolysis of biomass to produce char for carbon sequestration has multiple benefits... The product... is... called or Agri-char, sometimes (dark earth)... Trials in Australia have produced a doubling... or tripling of crop production... [C]har is likely to retain some... , , and ... Biochars are very porous... taking up and holding moisture. ...By ...stimulating plant growth, biochar has a double impact... First, it... sequesters carbon. Second... increased growth of plants removes CO, from the atmosphere..."

"Annual production of worldwide amounts to some four gigatonnes. A pyrolysis... that yielded only ten percent could produce enough to fertilize some forty million hectares..."

"s are... ancient technology. Biomass pyrolysis would be "low tech." Farmers could build and install their own... Alternatively, a biochar kiln could be mounted on... a truck... and taken from farm to farm..."

"A comprehensive program..: harvesting and shipping biomass to a centralized biomass or plant within the economically limiting radius, and beyond... converting biomass to biochar in small, decentralized units."