Applications of Lime

The paper and pulp industries consume taif/e quantities of Ca(OH)2 and precipitated (as distinct from naturally occurring) CaCOs. The largest application of lime in pulp manufacture is as a causlicizing agent in sulfate (kraft) plants (p. 89). Here the waste NajC solution is reacted with lime to regenerate the caustic soda used in the process ... 

Slurry is rich in nitrogen and potash but low in lime and phosphate. The result of over-application is to make the grassland coarse. This can be counter-balanced by the application of lime and an allowable form of phosphate. 

Plants readily accumulate lead from soils of low pH or low organic content however, uptake is significantly reduced after the application of lime or phosphate, which converts lead to hydroxides, carbonates, or phosphates of relatively low solubility (Demayo et al. 1982). Lead persists for lengthy periods in forest litter the estimated Tb 1/2 is 220 years (Turner et al. 1985). High levels of lead persisted for at least 6 years in litter, soil, amphibians, and mammals after zinc smelting was discontinued in Palmerton, Pennsylvania (Storm et al. 1994). Lead seems to be tightly bound by... 

Before the availability of artificial fertilizers in the mid-19th century, farms were traditionally organic, with recycling of animal waste, and perhaps with the application of lime on acid soils. Agricultural chemical analysis may have begun with Carl Wilhelm Scheele (1742-1786), the Swedish pharmacist who isolated citric acid from lemons and gooseberries and malic acid from apples. In France, Nicolas Theodore de Saussure (1767-1845) studied the mineral composition of plant ash, and in Britain, Sir Humphrey Davy... 

Tabtabaei, A., 1982, Application of Lime Stabilized Geomaterials in Road Construction, TechnicalJournal of Tehran University, No. 44, pp. 47-58. 

Molybdenum is present in the lithosphere and soils in extremly small quantities, averaging about 2 /ug g" (Swaine, 1955). This element is required by plants in very small quantities, but Mo deficiencies are quite common, particularly in Australia, New Zealand, and North America. Deficiencies are most frequently noted on legumes, since Mo is essential for symbiotic N-fixa-tion. However, Mo deficiency has also been observed on many other agronomic and horticultural crops. The availability of Mo to crops is greatly influenced by soil pH availability is increased by application of lime. Vegetation grown on soils high in Mo content may be toxic to livestock, but Mo toxicity in plants appears to be very rare. 

The subsurface horizons are commonly red or yellow owing to the accumulation of free oxides of iron, although some weatherable minerals are retained in the soil profile. Ultisols are acidic and have low fertility and low base status. Ultisols are not naturally fertile, but have enormous potential for agricultural productivity when properly managed through applications of lime and fertilizer (20, 21). 

The largest applications of lime treatment are roads, airports, car and lorry parks, where lime may be used to stabilise the subgrade to provide a capping layer , or to produce a stabilised subbase . Figure 26.3 illustrates these terms. 

This chapter and chapters 31 and 32 describe a large number of applications of lime products, most of which represent a small proportion of the total production. Because of the difficulty of categorising many of them, they have been divided between the three chapters in what may appear to be a somewhat arbitrary way. The contents of each chapter are therefore summarised at the start of each chapter (see Table 30.1). 

This chapter describes a variety of applications of lime products (Table 32.1) not included in Agriculture, food and food by-products (see Table 30.1), or Production of chemicals (see Table 31.1). 

Deep plowing or subsoihng with accompanying additions of lime is one method by which the bad conditions can be improved. Applications of lime to the upper 4- to 6-inch layer of soil will commonly have little first-season effect on the subsoil, and if roots do not grow there extensively water-use efficiency and crop yields will be low. 

I The color of hydrangea blossoms depends on the pH of the soil in which they are grown. Acidic soil (created by the application of ferrous sulfate, or FeSO ) creates blue blossoms. Alkaline soil (created by the application of lime) creates pink blossoms. 

Lime and fertiliser requirements. Some soil types have different abilities both to hold and release nntrients. Most clay minerals have a negative charge which attracts positively charged ions such as potassium, magnesium and calcium. This is called the cation exchange capacity. The presence of these charged sites affects the availability of nutrients. Sand and silt are relatively inert. Different soil textures with the same level of acidity have different recormnendations for the application of lime. This is due to differences in the cation exchange capacity of the soil. 

Although much larger applications of lime, than of fertilisers, are made as routine to agricultural land, the levels of essential trace elements in limestone are generally so low that liming materials do not seem to make any great contribution either, to the reserves in the soil. 

Calcium-deficient soils are relatively uncommon. Application of lime, a process used to treat acid soils (see Section 18.3), provides a more than adequate calciirm supply for plants. However, calcium uptake by plants and leaching by carbonic acid... 

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