Bark residue is an abundant waste material of the forest industry. In the province of Quebec alone 2.5 Mt (dry basis) are produced every year. This material can be transformed by vacuum pyrolysis into useful products. The Pyrocycling~(~R) process is conducted at a temperature and total pressure of approximately 450 - 500°C and 20 kPa, respectively. Pyrocycling~(~R) of bark residues @ 4 % moisture yields approximately 14 % gas, 21 % water, 31 % oil and 34 % charcoal. The gas is used as a make up heat source to supply the energy required for the pyrolysis process. The oil is a source of valuable chemicals, such as phenols. In this work the pyrolytic charcoal was tested as feedstock for the production of activated carbon. An important difference between vacuum pyrolysis and traditional atmospheric pyrolysis conducted at temperatures up to 500°C is that during the vacuum process the residence time of the gas and vapours evolved during the thermal decomposition process is short. Thus, secondary reactions, such as deposition of pyrolysis vapours in charcoal pores and formation of carbonaceous deposits are limited. The vacuum pyrolysis process was developed in this laboratory first at the bench scale, then with a process development unit (PDU) with a capacity of 100 kg/h and finally using an industrial scale reactor of industrial scale (3.5 t/h) which operation started in the Spring of 1999 in Jonquiere (Qc) Canada.
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机译：树皮残留物是林业的一种丰富的废料。仅在魁北克省，每年就生产2.5吨（干基）。可以通过真空热解将该物质转化为有用的产物。热循环法分别在约450-500℃和20kPa的温度和总压力下进行。水分含量为4％的树皮残留物的热循环会产生大约14％的气体，21％的水，31％的油和34％的木炭。该气体用作补充热源，以提供热解过程所需的能量。油是有价值的化学物质的来源，例如苯酚。在这项工作中，对热解木炭作为生产活性炭的原料进行了测试。真空热解与传统的高温热解在高达500°C的温度下进行的重要区别在于，在真空过程中，气体和蒸汽在热分解过程中产生的停留时间很短。因此，限制了次级反应，例如热解蒸气在木炭孔中的沉积和碳质沉积物的形成。该实验室首先在实验室规模上开发了真空热解工艺，然后使用了产能为100 kg / h的工艺开发单元（PDU），最后使用了工业规模（3.5 t / h）的工业规模反应器进行了操作。于1999年春季在加拿大的Jonquiere（Qc）成立。
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