title: Fifteenth century earth science

authors: Stokes, Evelyn

abstract: The earth science content of two late medieval encyclopedias, the Mirrour of the World and Higden's Polychronicon, both printed by William Caxton in the 1480's, is examined in relation to fifteenth century ideas about the physical nature of the earth and the universe. Such topics as the four elements, the earth and the spheres, location of Hell and Paradise, the arrangement of , continents and oceans, the unity of waters, earthquakes and volcanoes, erosion, fossils and mountain building, climatic zones and weather phenomena are summarized and reference made to the Biblical and Classical Greek sources of these ideas.

text: Fifteenth century earth science The earth science content of two late medieval encyclopedias, the Mirrour of the World and Higden's Polychronicon, both printed by William Caxton in the 1480's, is examined in relation to fifteenth century ideas about the physical nature of the earth and the universe. Such topics as the four elements, the earth and the spheres, location of Hell and Paradise, the arrangement of , continents and oceans, the unity of waters, earthquakes and volcanoes, erosion, fossils and mountain building, climatic zones and weather phenomena are summarized and reference made to the Biblical and Classical Greek sources of these ideas.

year: 1967

title: Pyrolysis of Sawdust

authors: Sichone, Kavwa

abstract: Lakeland Steel Limited developed a pilot plant for biomass pyrolysis based on sawdust. The pilot plant was based on an auger screw design which was indirectly heated using a double pipe heat exchange configuration to prevent oxidation (combustion) of the feedstock. This thesis covers the preliminary assessment of sawdust pyrolysis for R.H Tregoweth sawmills on behalf of Lakeland Steel Limited. 
Proximate and ultimate analyses were deployed on the sawdust to determine its composition. Proximate analysis results gave a moisture content of 60%. The dry solids had an organic matter content of 99.22% with ash making the balance. Ultimate analysis was used to determine content levels of elemental carbon, hydrogen, nitrogen sulphur and oxygen. The results on a dry basis were 47.2%, 6.5%, 0.3%, 0.3%, and 44.9 % respectively. 
Drying models were also used to analyse the sawdust drying characteristics. Drying curves were obtained experimentally and four models: Newton; Page; Henderson and Pabis; and Simpson and Tschernitz, were fitted to the data and their accuracy of fit was determined using residual squared sum of errors.  Page’s model was used to describe the sawdust behaviour in the dryer design as it had the highest accuracy.
The sawdust reaction kinetics were determined using data from thermogravimetric analysis (TGA) and analysed using distributed action energy model. The kinetics were observed at three heating rates of 10, 20 and 30 °C/min with a maximum temperature of 900°C under an argon atmosphere. Sawdust was modelled as a mixture of water, hemicellulose, cellulose  and lignin. Good agreement between Gaussian distribution functions for each component and experimental data were observed. 
Pilot plant trials were performed using a three factor-three level design of experiment. The factors under investigation were; feedstock moisture content with levels at 15, 30 and 60; reaction temperature with levels at 400, 450 and 500°C; and reactor auger speed with levels at 15, 20 and 25 rpm. Experiments at 60% moisture could not be performed to completion as the auger blocked repeatedly. The other two moisture contents showed that moisture content enhanced heat exchange properties of the feedstock and this generally increased the amount of volatile organic matter released. It was observed that for 15% moisture sawdust increase of temperature did not consistently exhibit an increase in degree of devolatilisation of organic matter. However, the 30% moisture sawdust showed an increase in devolatilisation with increase in temperature.  The effects of increasing reactor auger speed had the most consistent trend with which an increase in speed showed a decrease in degree of devolatilisation thus increasing char yield.
The empirical data collected from lab scale and pilot plant experiments were used to create mass and energy balances. These were the basis of the large scale mobile pyrolysis plant which was designed to process 3.45 tonnes per hour. Due to size restrictions the large scale dryer was not fitted in the container. It was then determined that the feedstock would either be dried using an onsite kiln or the reactor would process green sawdust.

A preliminary economic feasibility assessment was performed for the base case scenario which processed pre-dried sawdust of 15% moisture content at 400°C and a retention time of 45 minutes. A sensitivity analysis based on predicted optimistic and pessimistic conditions showed that automation of the plant had the potential to increase the economic viability of the large scale process.

text: Pyrolysis of Sawdust Lakeland Steel Limited developed a pilot plant for biomass pyrolysis based on sawdust. The pilot plant was based on an auger screw design which was indirectly heated using a double pipe heat exchange configuration to prevent oxidation (combustion) of the feedstock. This thesis covers the preliminary assessment of sawdust pyrolysis for R.H Tregoweth sawmills on behalf of Lakeland Steel Limited. 
Proximate and ultimate analyses were deployed on the sawdust to determine its composition. Proximate analysis results gave a moisture content of 60%. The dry solids had an organic matter content of 99.22% with ash making the balance. Ultimate analysis was used to determine content levels of elemental carbon, hydrogen, nitrogen sulphur and oxygen. The results on a dry basis were 47.2%, 6.5%, 0.3%, 0.3%, and 44.9 % respectively. 
Drying models were also used to analyse the sawdust drying characteristics. Drying curves were obtained experimentally and four models: Newton; Page; Henderson and Pabis; and Simpson and Tschernitz, were fitted to the data and their accuracy of fit was determined using residual squared sum of errors.  Page’s model was used to describe the sawdust behaviour in the dryer design as it had the highest accuracy.
The sawdust reaction kinetics were determined using data from thermogravimetric analysis (TGA) and analysed using distributed action energy model. The kinetics were observed at three heating rates of 10, 20 and 30 °C/min with a maximum temperature of 900°C under an argon atmosphere. Sawdust was modelled as a mixture of water, hemicellulose, cellulose  and lignin. Good agreement between Gaussian distribution functions for each component and experimental data were observed. 
Pilot plant trials were performed using a three factor-three level design of experiment. The factors under investigation were; feedstock moisture content with levels at 15, 30 and 60; reaction temperature with levels at 400, 450 and 500°C; and reactor auger speed with levels at 15, 20 and 25 rpm. Experiments at 60% moisture could not be performed to completion as the auger blocked repeatedly. The other two moisture contents showed that moisture content enhanced heat exchange properties of the feedstock and this generally increased the amount of volatile organic matter released. It was observed that for 15% moisture sawdust increase of temperature did not consistently exhibit an increase in degree of devolatilisation of organic matter. However, the 30% moisture sawdust showed an increase in devolatilisation with increase in temperature.  The effects of increasing reactor auger speed had the most consistent trend with which an increase in speed showed a decrease in degree of devolatilisation thus increasing char yield.
The empirical data collected from lab scale and pilot plant experiments were used to create mass and energy balances. These were the basis of the large scale mobile pyrolysis plant which was designed to process 3.45 tonnes per hour. Due to size restrictions the large scale dryer was not fitted in the container. It was then determined that the feedstock would either be dried using an onsite kiln or the reactor would process green sawdust.

A preliminary economic feasibility assessment was performed for the base case scenario which processed pre-dried sawdust of 15% moisture content at 400°C and a retention time of 45 minutes. A sensitivity analysis based on predicted optimistic and pessimistic conditions showed that automation of the plant had the potential to increase the economic viability of the large scale process.

year: 2013

title: Hāwatewate

authors: Maxwell, Te Kahautu

subjects: Whakaeke

abstract: He whakamārama mō te whakaeke apakura
He whakaeke apakura tēnei hai whakamaumaharatanga ki te kotahi rau e rima tekau tau mai i te murunga whenua o Te Whakatōhea. Ka tangihia te tāwharonanga harakoretanga o Mokomoko tipuna o Te Whakatōhea. I whakapaetekatia e Te Karauna nāna i kōhuru te mihinare a Te Wākana i te 2 o Poutūterangi i te tau kotahi mano e waru rau e ono tekau mā rima (1865). Ahakoa nā Kereopa o Ngāti Rangiwewehi i patu a Te Wākana. I haramai a Te Kereopa i raro i te Paimārire (Hauhau) ki Ōpōtiki. Ko tā Te Paimārire kaupapa i tae atu ai ko te kauhau i te whakapono hou a Te Ua Haumēne. Ko ngā āpōtoro i tukuna atu e Te Ua Haumēne ko Pātara Rakataura me Te Kereopa, hoi anō ko te kauhau i te rongopai tā Te Ua Haumēne i whakahau ai. Hoi anō he take tā Te Kereopa, tā te mea i kōhurutia tana wahine me āna tamāhine tokorua ki te whare karakia i Rangiaowhia ki roto o Tainui. Nara i pau a Ngāti Apakura ki te mate, ā i patua anō tana tamāhine hoki ki te pakanga i Hairini. Koiarā tā Kereopa he rānaki i te mate o tana whānau i pau i te ahi nukarau a te Karauna. Nā tēnei patunga i a Te Wākana i riro ai te 250,000 eka o Te Whakatōhea. I tēnei rā tonu o Te Matatini i tēnei tau 2015 kua eke ki te kotahi rau e rima tekau (150) tau o te parekuranui o Te Whakatōhea mō te patunga i te tangata kotahi nā tētahi atu. Ko te kōhuru i a Te Whakatōhea me āna tamariki, āna mokopuna, ko te tāwharona i ngā tāne, i ngā wāhine, ko te ekeeke kino te rarahu i ngā wāhine me ngā tamariki kōtiro, tāne hoki. Mutu ana te rarahu ko te kōhuru i a rātou ki te pū, ki te mata o te pēneti ko te tahu rānei. Ko te urupatu anō tērā ko te tahu i ngā pā, i ngā whare tīpuna, i ngā māra, i ngā mira mahi paura, i ngā kaipuke tauhokohoko ki Tāmaki, ki Poihākena, ki Ingarangi. Ko te parekura nui tēnei o Te Whakatōhea, ko te kōhuru i tō mātou katoa, tō mātou ao, tō mātou wairua, tō mātou hinengaro, tō mātou tinana o Te Whakatōhea mō te mate kotahi a te tangata kotahi. Ahakoa he mihingare, he pūrahorua hoki he kawe o kōrero nōna ki a Kāwana Kerei mō ngā nekeneke a Te Whakatōhea ki te tautoko i a Kīngi Tāwhiao me ngā pakanga whenua i Rangiriri, i Ōrakau i te tau kotahi mano e waru rau e ono tekau mā whā (1864).

text: Hāwatewate He whakamārama mō te whakaeke apakura
He whakaeke apakura tēnei hai whakamaumaharatanga ki te kotahi rau e rima tekau tau mai i te murunga whenua o Te Whakatōhea. Ka tangihia te tāwharonanga harakoretanga o Mokomoko tipuna o Te Whakatōhea. I whakapaetekatia e Te Karauna nāna i kōhuru te mihinare a Te Wākana i te 2 o Poutūterangi i te tau kotahi mano e waru rau e ono tekau mā rima (1865). Ahakoa nā Kereopa o Ngāti Rangiwewehi i patu a Te Wākana. I haramai a Te Kereopa i raro i te Paimārire (Hauhau) ki Ōpōtiki. Ko tā Te Paimārire kaupapa i tae atu ai ko te kauhau i te whakapono hou a Te Ua Haumēne. Ko ngā āpōtoro i tukuna atu e Te Ua Haumēne ko Pātara Rakataura me Te Kereopa, hoi anō ko te kauhau i te rongopai tā Te Ua Haumēne i whakahau ai. Hoi anō he take tā Te Kereopa, tā te mea i kōhurutia tana wahine me āna tamāhine tokorua ki te whare karakia i Rangiaowhia ki roto o Tainui. Nara i pau a Ngāti Apakura ki te mate, ā i patua anō tana tamāhine hoki ki te pakanga i Hairini. Koiarā tā Kereopa he rānaki i te mate o tana whānau i pau i te ahi nukarau a te Karauna. Nā tēnei patunga i a Te Wākana i riro ai te 250,000 eka o Te Whakatōhea. I tēnei rā tonu o Te Matatini i tēnei tau 2015 kua eke ki te kotahi rau e rima tekau (150) tau o te parekuranui o Te Whakatōhea mō te patunga i te tangata kotahi nā tētahi atu. Ko te kōhuru i a Te Whakatōhea me āna tamariki, āna mokopuna, ko te tāwharona i ngā tāne, i ngā wāhine, ko te ekeeke kino te rarahu i ngā wāhine me ngā tamariki kōtiro, tāne hoki. Mutu ana te rarahu ko te kōhuru i a rātou ki te pū, ki te mata o te pēneti ko te tahu rānei. Ko te urupatu anō tērā ko te tahu i ngā pā, i ngā whare tīpuna, i ngā māra, i ngā mira mahi paura, i ngā kaipuke tauhokohoko ki Tāmaki, ki Poihākena, ki Ingarangi. Ko te parekura nui tēnei o Te Whakatōhea, ko te kōhuru i tō mātou katoa, tō mātou ao, tō mātou wairua, tō mātou hinengaro, tō mātou tinana o Te Whakatōhea mō te mate kotahi a te tangata kotahi. Ahakoa he mihingare, he pūrahorua hoki he kawe o kōrero nōna ki a Kāwana Kerei mō ngā nekeneke a Te Whakatōhea ki te tautoko i a Kīngi Tāwhiao me ngā pakanga whenua i Rangiriri, i Ōrakau i te tau kotahi mano e waru rau e ono tekau mā whā (1864).

year: 2017