Dynamic management and control of the risk of carbon dioxide content exceeding the standard in green food production base

Author(s):  
Shengli Xu
1991 ◽  
Vol 24 (7) ◽  
pp. 277-284 ◽  
Author(s):  
E. Gomólka ◽  
B. Gomólka

Whenever possible, neutralization of alkaline wastewater should involve low-cost acid. It is conventional to make use of carbonic acid produced via the reaction of carbon dioxide (contained in flue gases) with water according to the following equation: Carbon dioxide content in the flue gas stream varies from 10% to 15%. The flue gas stream may either be passed to the wastewater contained in the recarbonizers, or. enter the scrubbers (which are continually sprayed with wastewater) from the bottom in oountercurrent. The reactors, in which recarbonation occurs, have the ability to expand the contact surface between gaseous and liquid phase. This can be achieved by gas phase dispersion in the liquid phase (bubbling), by liquid phase dispersion in the gas phase (spraying), or by bubbling and spraying, and mixing. These concurrent operations are carried out during motion of the disk aerator (which is a patent claim). The authors describe the functioning of the disk aerator, the composition of the wastewater produced during wet gasification of carbide, the chemistry of recarbonation and decarbonation, and the concept of applying the disk aerator so as to make the wastewater fit for reuse (after suitable neutralization) as feeding water in acetylene generators.


2021 ◽  
Vol 13 (7) ◽  
pp. 3660
Author(s):  
Rathna Hor ◽  
Phanna Ly ◽  
Agusta Samodra Putra ◽  
Riaru Ishizaki ◽  
Tofael Ahamed ◽  
...  

Traditional Cambodian food has higher nutrient balances and is environmentally sustainable compared to conventional diets. However, there is a lack of knowledge and evidence on nutrient intake and the environmental greenness of traditional food at different age distributions. The relationship between nutritional intake and environmental impact can be evaluated using carbon dioxide (CO2) emissions from agricultural production based on life cycle assessment (LCA). The objective of this study was to estimate the CO2 equivalent (eq) emissions from the traditional Cambodian diet using LCA, starting at each agricultural production phase. A one-year food consumption scenario with the traditional diet was established. Five breakfast (BF1–5) and seven lunch and dinner (LD1–7) food sets were consumed at the same rate and compared using LCA. The results showed that BF1 and LD2 had the lowest and highest emissions (0.3 Mt CO2 eq/yr and 1.2 Mt CO2 eq/yr, respectively). The food calories, minerals, and vitamins met the recommended dietary allowance. The country’s existing food production system generates CO2 emissions of 9.7 Mt CO2 eq/yr, with the proposed system reducing these by 28.9% to 6.9 Mt CO2 eq/yr. The change in each food item could decrease emissions depending on the type and quantity of the food set, especially meat and milk consumption.


1973 ◽  
Vol 10 (2) ◽  
pp. 306-315 ◽  
Author(s):  
T. M. L. Wigley

The effect of the addition of gypsum to a solution of calcite in water (or the addition of calcite to a solution of gypsum in water) is determined theoretically for arbitrary temperature, carbon dioxide content, and degree of saturation with respect to calcite (or gypsum). The results can be used to study the chemical evolution of waters flowing through alternating gypsum and limestone strata, to predict conditions which will lead to the precipitation of calcite and/or gypsum, and to predict the chemical evolution of evaporating calcite–gypsum solutions. It is shown that under some circumstances, simultaneous gypsum (or calcite) precipitation and calcite (or gypsum) solution may occur. Coprecipitation of gypsum and calcite is found to be unavoidable if a solution is evaporated to dryness, although the initial precipitate will be a single mineral. The methods used and many of the conclusions drawn are applicable to other systems of two or more minerals.


1957 ◽  
Vol 24 (2) ◽  
pp. 235-241 ◽  
Author(s):  
P. S. Robertson

Some of the factors influencing the concentration of carbon dioxide found in New Zealand Cheddar cheese have been investigated.1. Cheeses made with the use of commercial starters (containing betacocci) are characterized by a rapid increase in their carbon dioxide content during the 2 weeks following manufacture.2. Cheeses made with the use of single strain starters do not change in carbon dioxide content in the first 2 weeks following manufacture, but may ultimately contain as much carbon dioxide as commercial starter cheeses.3. High concentrations of carbon dioxide within a cheese result in an open texture, especially when the carbon dioxide is formed shortly after manufacture.4. The loss of carbon dioxide to the atmosphere is demonstrated by the existence of a carbon dioxide concentration gradient within the cheese.5. Storage of cheese at a lower temperature than is usual results in retarded carbon dioxide formation.


2018 ◽  
Vol 200 ◽  
pp. 269-281 ◽  
Author(s):  
Alessandra de Carvalho Reis ◽  
José Luiz de Medeiros ◽  
Giovani Cavalcanti Nunes ◽  
Ofélia de Queiroz Fernandes Araújo

1929 ◽  
Vol 6 (4) ◽  
pp. 340-349 ◽  
Author(s):  
ALFRED C. REDFIELD ◽  
ROBERT GOODKIND

1. The oxygen and carbon-dioxide content of the arterial and venous blood of the squid, Loligo pealei, have been measured. 2. Using a nomographic method of analysis it is shown that the reciprocal effects of oxygen and carbon dioxide upon the respiratory properties of squid haemocyanin account for one-third of the respiratory exchange. 3. The venous blood is estimated to be 0.13 pH unit more acid than the arterial blood. 4. Death from asphyxiation occurs when the oxygen and carbon-dioxide pressures are such that the arterial blood can combine with only 0.5 to 1.5 volumes per cent, oxygen. Carbon dioxide exerts no toxic effect except through its influence on the oxygenation of the blood. 5. The haemocyanin of the blood is of vital necessity to the squid, because the amount of oxygen which can be physically dissolved in blood is less than the amount which is necessary for the maintenance of life.


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