title: Investigation of anti-fouling processing aids in the primary evaporation of whey permeate

authors: Harrison, Dylan

subjects: whey permeate

abstract: The production of lactose via the concentration of whey permeate is an important process in the dairy industry. Hautapu dairy factory, owned by Fonterra Cooperative Group, process milk into a range of dairy-based products including; Cheese, Milk Protein Concentrate and Lactose. This project was focused around reducing fouling during the evaporation of whey permeate for the production of lactose powder. As whey permeate is heated in evaporators, mineral salts precipitate and accumulate onto the stainless steel heat exchange surfaces. This layer of mineral scale, known as fouling, greatly reduces the amount of heat transfer used for evaporating the whey permeate. Once the fouling gets to a point where it is no longer achievable to reach the concentrated solids target, the evaporator is shut down and cleaned with chemicals to remove the scale build up.

To decrease the amount of scale build up, a process aid is added to the whey permeate. This process aid A , or PAA, is a polyphosphate that when added to the feed stream gives longer run times. This project was aimed at establishing the chemistry behind the inhibiting abilities of PAA and its interaction with whey permeate. It is known that PAA acts as a complexing agent with calcium when it is added to the permeate stream which prevents it from forming calcium phosphate, the main source of fouling.

In the course of the research, it was fortuitously discovered that PAA works very inefficiently as an inhibitor in whey permeate because of its ability to form an insoluble salt with free calcium ions. The consequence of this was that high calcium levels in whey permeate lead to PAA precipitating out of solution rendering it an ineffective anti-fouling agent to prevent further scale build up. As a result of this, alternative inhibitors were considered and tested for their calcium tolerance and calcium phosphate inhibiting properties. From these considerations, carboxymethyl inulin was regarded as the most favourable replacement candidate for PAA. This resulted in plans being set down for a future industrial trial involving the carboxymethyl inulin.

text: Investigation of anti-fouling processing aids in the primary evaporation of whey permeate The production of lactose via the concentration of whey permeate is an important process in the dairy industry. Hautapu dairy factory, owned by Fonterra Cooperative Group, process milk into a range of dairy-based products including; Cheese, Milk Protein Concentrate and Lactose. This project was focused around reducing fouling during the evaporation of whey permeate for the production of lactose powder. As whey permeate is heated in evaporators, mineral salts precipitate and accumulate onto the stainless steel heat exchange surfaces. This layer of mineral scale, known as fouling, greatly reduces the amount of heat transfer used for evaporating the whey permeate. Once the fouling gets to a point where it is no longer achievable to reach the concentrated solids target, the evaporator is shut down and cleaned with chemicals to remove the scale build up.

To decrease the amount of scale build up, a process aid is added to the whey permeate. This process aid A , or PAA, is a polyphosphate that when added to the feed stream gives longer run times. This project was aimed at establishing the chemistry behind the inhibiting abilities of PAA and its interaction with whey permeate. It is known that PAA acts as a complexing agent with calcium when it is added to the permeate stream which prevents it from forming calcium phosphate, the main source of fouling.

In the course of the research, it was fortuitously discovered that PAA works very inefficiently as an inhibitor in whey permeate because of its ability to form an insoluble salt with free calcium ions. The consequence of this was that high calcium levels in whey permeate lead to PAA precipitating out of solution rendering it an ineffective anti-fouling agent to prevent further scale build up. As a result of this, alternative inhibitors were considered and tested for their calcium tolerance and calcium phosphate inhibiting properties. From these considerations, carboxymethyl inulin was regarded as the most favourable replacement candidate for PAA. This resulted in plans being set down for a future industrial trial involving the carboxymethyl inulin.

year: 2009

title: Chinese postgraduates' explanation of the sources of sentence initial bundles in their thesis writing

authors: Li, Liang

subjects: computer science

abstract: Lexical bundles, recurrent multiword combinations in a register, are extremely common and important discourse building blocks in academic writing. An increasing number of studies have investigated lexical bundles in academic writing in recent years, but few studies have explored L2 learners’ interpretations of their own bundle production, particularly sentence initial bundle production. Investigating the sources that have appeared to influence learners’ choices and knowledge of bundles is important as it complements what we know about the structural and functional features of lexical bundles and provides useful first-hand information for second language writing pedagogy. The present study interviewed five Chinese postgraduate students to probe possible reasons for their use of the typical sentence initial bundles identified in the self-built Chinese Masters and PhD thesis corpora. The interviews revealed diverse explanations including interlingual transfer, classroom learning, noticing in reading, a lack of rhetorical confidence, and misunderstanding of rhetorical conventions. The results suggest the need for raising students’ awareness of the common sentence starters in postgraduate academic writing, increasing their confidence as student writers, familiarizing them with rhetorical conventions, and incorporating effective corpus-based tools into pedagogical practices.

text: Chinese postgraduates' explanation of the sources of sentence initial bundles in their thesis writing Lexical bundles, recurrent multiword combinations in a register, are extremely common and important discourse building blocks in academic writing. An increasing number of studies have investigated lexical bundles in academic writing in recent years, but few studies have explored L2 learners’ interpretations of their own bundle production, particularly sentence initial bundle production. Investigating the sources that have appeared to influence learners’ choices and knowledge of bundles is important as it complements what we know about the structural and functional features of lexical bundles and provides useful first-hand information for second language writing pedagogy. The present study interviewed five Chinese postgraduate students to probe possible reasons for their use of the typical sentence initial bundles identified in the self-built Chinese Masters and PhD thesis corpora. The interviews revealed diverse explanations including interlingual transfer, classroom learning, noticing in reading, a lack of rhetorical confidence, and misunderstanding of rhetorical conventions. The results suggest the need for raising students’ awareness of the common sentence starters in postgraduate academic writing, increasing their confidence as student writers, familiarizing them with rhetorical conventions, and incorporating effective corpus-based tools into pedagogical practices.

year: 2018

title: Cultural justice, ethics and teaching

authors: Nairn, Ray

subjects: Maori

abstract: Te Tiriti o Waitangi provides both a basis for cultural justice in this society and an explication of the term; each of the articles identifying a significant aspect of cultural justice. First, there is the guarantee to the Maori signatories that the Crown would protect their independence - tino rangatiratanga, (also read as authority, autonomy or self-determination) [Article II]. In Article III Maori are promised that they will also have the “Rights and Privileges of British subjects”. Finally, in Article I, Maori cede to the Crown the right to govern, to make laws to protect all peoples from the evil consequences of lawlessness. The 1835 Declaration of Independence located legislative authority in the Wakaminenga (the gathered rangatira meeting in Congress); and in 1840, in the context of the Crown promises, Maori authorised the Crown to exercise that authority. For Maori Te Tiriti specifies cultural justice for interactions between Maori and settlers in the new society. Maori are guaranteed the right to self-determination (and the economic and social resources to make that practical) in their relations with New Zealand society. They are also entitled to the same opportunities as other citizens. The latter rights, embodied in local legislation and international covenants to which we are signatory, are not alternatives to the prior right of Maori people to their (cultural) autonomy. The exercise of legislative and organisational authority must be exercised in a manner consistent with the promises which clearly requires consultation and negotiation with Maori.

text: Cultural justice, ethics and teaching Te Tiriti o Waitangi provides both a basis for cultural justice in this society and an explication of the term; each of the articles identifying a significant aspect of cultural justice. First, there is the guarantee to the Maori signatories that the Crown would protect their independence - tino rangatiratanga, (also read as authority, autonomy or self-determination) [Article II]. In Article III Maori are promised that they will also have the “Rights and Privileges of British subjects”. Finally, in Article I, Maori cede to the Crown the right to govern, to make laws to protect all peoples from the evil consequences of lawlessness. The 1835 Declaration of Independence located legislative authority in the Wakaminenga (the gathered rangatira meeting in Congress); and in 1840, in the context of the Crown promises, Maori authorised the Crown to exercise that authority. For Maori Te Tiriti specifies cultural justice for interactions between Maori and settlers in the new society. Maori are guaranteed the right to self-determination (and the economic and social resources to make that practical) in their relations with New Zealand society. They are also entitled to the same opportunities as other citizens. The latter rights, embodied in local legislation and international covenants to which we are signatory, are not alternatives to the prior right of Maori people to their (cultural) autonomy. The exercise of legislative and organisational authority must be exercised in a manner consistent with the promises which clearly requires consultation and negotiation with Maori.

year: 1993