title: Total site utility systems optimisation for milk powder production

authors: Walmsley, Timothy Gordon

abstract: This study applies the Total Site Heat Integration method, in conjunction with a detailed process and utility model, to investigate three methods to increase the energy efficiency of the utility supply system for milk powder production. Sequentially explored opportunities are: (1) increasing boiler efficiency through condensing economisers, (2) waste heat recovery from the chiller unit, and (3) Combined Heat and Power (CHP) for electricity production. The basis for the analysis is the anticipated future milk powder process design, which incorporates results from recent studies that have focused on improving the process design and integration of the heat treatment and evaporator systems and recovering heat from the spray dryer exhaust, which show a combined specific fuel consumption reduction of 29.6 % and a relatively small increase in electricity use of 4.5 %. To maximise boiler efficiency, the study concludes that a condensing economiser for the flue gas can be indirectly matched with heating fluidised bed air flows through the boiler condensate system, which results in specific fuel use reduction of 227 MJ/tp. Chiller waste heat can be upgraded and integrated as a heat source to replace the equivalent specific fuel use of 101 MJ/tp through integration with the site low temperature hot water loop. By designing the steam system to maximise electricity generation in a new turbine, results show that 51 % of the site’s electricity demand may be satisfied by CHP. The combined effect of implementing these three utility systems opportunities is a specific fuel use of 3,868 MJ/tₚ, of which 530 MJ/tₚ result from electricity production, and a specific grid electricity demand of 113.4 kWh/tₚ.

text: Total site utility systems optimisation for milk powder production This study applies the Total Site Heat Integration method, in conjunction with a detailed process and utility model, to investigate three methods to increase the energy efficiency of the utility supply system for milk powder production. Sequentially explored opportunities are: (1) increasing boiler efficiency through condensing economisers, (2) waste heat recovery from the chiller unit, and (3) Combined Heat and Power (CHP) for electricity production. The basis for the analysis is the anticipated future milk powder process design, which incorporates results from recent studies that have focused on improving the process design and integration of the heat treatment and evaporator systems and recovering heat from the spray dryer exhaust, which show a combined specific fuel consumption reduction of 29.6 % and a relatively small increase in electricity use of 4.5 %. To maximise boiler efficiency, the study concludes that a condensing economiser for the flue gas can be indirectly matched with heating fluidised bed air flows through the boiler condensate system, which results in specific fuel use reduction of 227 MJ/tp. Chiller waste heat can be upgraded and integrated as a heat source to replace the equivalent specific fuel use of 101 MJ/tp through integration with the site low temperature hot water loop. By designing the steam system to maximise electricity generation in a new turbine, results show that 51 % of the site’s electricity demand may be satisfied by CHP. The combined effect of implementing these three utility systems opportunities is a specific fuel use of 3,868 MJ/tₚ, of which 530 MJ/tₚ result from electricity production, and a specific grid electricity demand of 113.4 kWh/tₚ.

year: 2016

title: The future of surrogacy in New Zealand – Beyond the adoption model

authors: van Zyl, Liezl

abstract: Surrogacy in New Zealand is treated as a form of adoption. ACART (2014) proposes that the Health Minister consider compensating women who act as surrogate mothers. We think this is a step in the right direction, but until the adoption model is abandoned surrogacy will not be a safe practice for New Zealanders. ACART’s consultation document does not address the issue of legal parenthood, but it is one that is intimately linked to the issue of compensation to surrogates because the Adoption Act (Section 25) prohibits payments in consideration of adoption. If, as we will argue below, surrogates deserve to be compensated for their labour, it is imperative that we acknowledge that the adoption framework is inappropriate in surrogacy.

text: The future of surrogacy in New Zealand – Beyond the adoption model Surrogacy in New Zealand is treated as a form of adoption. ACART (2014) proposes that the Health Minister consider compensating women who act as surrogate mothers. We think this is a step in the right direction, but until the adoption model is abandoned surrogacy will not be a safe practice for New Zealanders. ACART’s consultation document does not address the issue of legal parenthood, but it is one that is intimately linked to the issue of compensation to surrogates because the Adoption Act (Section 25) prohibits payments in consideration of adoption. If, as we will argue below, surrogates deserve to be compensated for their labour, it is imperative that we acknowledge that the adoption framework is inappropriate in surrogacy.

year: 2015

title: Measuring Wellbeing for Public Policy in a Bi-Cultural Nation: Update from Aotearoa New Zealand

authors: Weijers, Dan M.

abstract: A presentation at Measuring Wellbeing in a Multicultural World: An Interdisciplinary Workshop, Conference held at ANU, Canberra, Australia and online

text: Measuring Wellbeing for Public Policy in a Bi-Cultural Nation: Update from Aotearoa New Zealand A presentation at Measuring Wellbeing in a Multicultural World: An Interdisciplinary Workshop, Conference held at ANU, Canberra, Australia and online

year: 2023-08-11