Chemical Engineering

"A comprehensive review (189pp) of the 'cultural and historic heritage' issues raised in submissions to the Manukau City Council hearing the application to dispose biosolids to Te Motu a Hiaroa Puketutu Island. This review report is divided into seven sections. Under the heading ‘background’ (Section 2) the review objective is stated and the methodology outlined with some problem submissions highlighted for further discussion and resolution. Discussion of ‘statutory imperatives, policy and plans’ (Section 3) then summarises the formal recognition of and provision for Puketutu Island cultural heritage and lists 23 questions extracted to help focus the review. Each of the 26 submissions that raised cultural heritage issues is then examined under the heading ‘results’ (Section 4) within subheadings (individuals and whanau, group, companies, charitable trusts including marae, incorporated societies and independent statutory authorities); this aggregation of submissions was made to not only help recognise groups, but also to address issues from least complex to most complex, and to provide an inherent order whereby larger numbers of people could be recognised and provided for within the review. The primary cultural heritage technical report of the application is then examined under the heading ‘the completed archaeological assessment’ (Section 5). I have constrained the body of my comments to a ‘discussion’ (Section 6) focusing on the questions that were derived from statutes and plans. The review is completed with a brief ‘conclusion’, Figure 1 (a summary table of submissions analysed, issues raised and recommendations sought), a list of brief list of ‘references’ and an ‘appendix’ being a full copy of the submissions (pp.40 to 190).

Twenty-six submissions, out of a total of 107, were considered to have raised Maori, cultural heritage and archaeological issues. Twenty of these are in opposition and one in support. The remaining five submissions were ‘neutral’, that is, conditionally supportive or conditionally opposed to the application.

The one submission (No. 102) in support of the application is based on a perception that the sacredness (tapu) of Te Motu a Hiaroa has been diminished for one Iwi (Te Akitai) by post Maori occupation development activities (e.g. waste water treatment and quarrying, and possibly farming) that have occurred here.

The 20 submissions against the application, ask the MCC to uphold the statutory protection already provided to Puketutu Island through the RMA (policy statements and plans, including Iwi plans as listed above), through the Historic Places Act 1993 (in respect of archaeological sites), and through the Treaty of Waitangi and the related principles established by government. The broad conclusion is that the Island is a regionally significant heritage landscape, regardless of past European farming and quarrying practices, and it is not appropriate to use the Island for disposal of biosolids. Iwi and Maori, in particular, see the disposal of biosolids (human waste) on the Island as an inappropriate activity to be undertaken on a wahi tapu (sacred place).

Ian Lawlor
28 Apr 2009
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"Distillation is the most developed and most applied separation process (Ref. 1).

Recent advances in computational techniques and software allow rapid assessment of distillation requirements and as such are to be welcomed. However before attempting a detailed computed design process engineers should acquire a feel for the problem. This is readily achieved by applying simple physico-chemical concepts and shortcut methods - such an approach highlights any gross errors in the subsequent computed design.

One means of effecting a rough column design is presented and consideration is then given to the detail design using commercially available computer programs. Practical aspects of column design are appraised, some of the points raised appear facile but all have caused problems in the recent past. A worked example allows a comparison between the rough design and the computed design
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The article first describes characteristics of major infrastructure projects. Second, it documents a much neglected topic in economics: that ex ante estimates of costs and benefits are often very different from actual ex post costs and benefits. For large infrastructure projects the consequences are cost overruns, benefit shortfalls, and the systematic underestimation of risks. Third, implications for cost–benefit analysis are described, including that such analysis is not to be trusted for major infrastructure projects. Fourth, the article uncovers the causes of this state of affairs in terms of perverse incentives that encourage promoters to underestimate costs and overestimate benefits in the business cases for their projects. But the projects that are made to look best on paper are the projects that amass the highest cost overruns and benefit shortfalls in reality. The article depicts this situation as ‘survival of the unfittest’. Fifth, the article sets out to explain how the problem may be solved, with a view to arriving at more efficient and more democratic projects, and avoiding the scandals that often accompany major infrastructure investments. Finally, the article identifies current trends in major infrastructure development. It is argued that a rapid increase in stimulus spending, combined with more investments in emerging economies, combined with more spending on information technology is catapulting infrastructure investment from the frying pan into the fire.

"Reduction of water activity aw can extend the shelf life and improve the quality of foods. After the optimal water activity has been selected, based on Karel’s aw-spoilage graphs, a simple decision scheme in this document helps to choose the best equation (“Law”) to calculate or adjust the water activity: for an aqueous one component  solution: Raoult’s and Norrish’ laws; spreadsheet “aw-Raoult-Norrish.xls”; or in case of an aqueous multi-component solution: Norrish’ and Ross’ laws; spreadsheet “Norrish-Ross.xls: aw calculations of a multi-component solution”. Both Excel spreadsheets, present in this document, simplify the tedious exponential aw calculations.
The water activity of a mixture of 2 to 5 solids can be predicted either by constructing the solids mixture sorption isotherm, or by using the Salwin equation. When applying the 3rd spreadsheet in this document, “Calculation Water Activity aw Solids Mixture.xls”, the  2 to 5 separate solids isotherms are converted into one new solids mixture sorption isotherm. Because the total water content of the solids mixture is known, the water activity of the solids mixture can be found from that new mixture isotherm. The calculations by the “aw Solid Mixture” spreadsheet are compared with aw findings from Salwin’s equation. Both aw values are in good agreement.
Several worked examples, for each of the 3 spreadsheets present, illustrate step-by-step the aw calculation of solutions and of solid mixtures.
Annex 1 lists the lowest water activity for growth and/or toxin production of many micro-
organisms in foods. Annex 2 shows the minimal aw for activity of the main food spoiling enzymes.
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This case study examines how technology can be used to support an active learning strategy within face-to- face Chemistry classes. Both in-class polling software and online lectures are used as part of a comprehensive teaching strategy, designed to enable students to develop critical thinking and analytical skills. While in- class polling is not an online process, it is included within this case study to highlight how different types of technology can be used together to effectively support classroom teaching, when integrated with a carefully considered pedagogical approach.