Liming lime requirement

Determination of the pH Value of Sludge, Soil, Mud and Sediment and the Lime Requirement of Soil (Second Edition) (by Determination of the pH Value of Sludge, Soil, Mud and Sediment or by Determination of the Lime Requirement of Soil), 1992... 

Weight-up to overcome salt water flow. Chemical treatment as for salt rock. Run alkalinity test and calculate CO3 and HCO3 ions concentration. Calculate lime required ... 

Therefore, when developing an estimate of process engineering lime required, it is important to recognize the amount of effort that may be necessary to collect physical property data before any real work can commence. This same concern exists when evaluating K values and activity data for systems. 

Pure water in equilibrium with atmospheric CO has a pH of 5.6. If a soil pH is lower or higher than this, it is acting as an acid or base respectively. Several soil components act as buffers (hydroxy aluminium monomers or polymers, soil organic matter and undissolved carbonates), therefore lime requirement tests may also be required. 

Definition. The lime requirement of a mineral soil is the number of tonnes of calcium carbonate calculated to raise the pH of a hectare of soil 200 mm deep, under field conditions, to, and maintain at, 6.5. 

A low pH indicates that lime is required, but not the quantity. Excess is not only wasteful, but may render certain elements (e.g. Fe, Mn, and B) unavailable to plants. There are several methods for determining the lime requirement, including adding excess calcium bicarbonate and back-titrating the excess adding increasing amounts of calcium hydroxide and monitoring the pH and the use of a buffer solution (MAFF/ADAS, 1986, pp. 150-151), which will be described below. 

Calculation for mineral soils of pH 5.0-6.4. Subtract the indicated pH from 7.00 and multiply by 11.2. The result gives the lime requirement as tonnes ha calcium carbonate. 

Notwithstanding, however, that fire quantity of lime required may be well known, it is necessary to test the gas in its progress through the various purifiers. In some cases it is advisable to use the test every twelve hours, or oftener, in districts, for instance, where coal is of inferior and various qualities. Every morning, as soon as tho superintendent arrives at the works, he ought to test tho action of his purifiers, more especially if he has received a fresh supply of coal or lime. It is necessary only to drop a piece of paper into the plumbous solution, and hold it to the escape-hole of the purifier. Tho slightest coloration indicates impurity. 

The lime required lo evaluate new varieties and the number of field trials will vary depending on the need to confirm performance, to evaluate characteristics of the food, to evaluate environmental effects, and to produce the required amount of seed before the new plam variety can be grown commercially by farmers. 

Half-Life. Once these activation parameters have been determined lor a initiator, half-life times tit a given temperature, i.e.. the lime required for 50 decomposition at a selected temperature, and half-life temperatures for a given period, i.e.. the temperature required for 509f decomposition of an initiator over a given time, can be calculated. Half life data arc useful for comparing the activity or one initiator with another when the half-life data arc determined in the same solvent and at the same concentration and. preferably, when the initiators are of the same class. 

Limes require warm and humid weather conditions in order to thrive on a commercial scale. India, Egypt, Africa, Mexico and the West Indies are therefore prime growing areas. Mexico and the West Indies together produce a large percentage of the world s lime crop. Relative to the other citrus fruits, limes are a small round fruit they are green or greenish yellow in colour, and not more than 8-10 cm in diameter, with a sharp, fresh and characteristic flavour. 

Ventre and co-workers,72-78 in later work, found that the addition of calcium chloride greatly increased the amount of aconitates thus recovered. The procedure used was as follows lime was added to a quantity of sorghum juice to adjust the pH value to approximately 6.9. The amount of lime required for this treatment was calculated as equivalents of aconitic acid and this portion of the aconitic acid in the original sample of juice was assumed to be free aconitic acid. The remaining aconitic acid was assumed to be bound in the form of a soluble aconitate. An amount of calcium chloride equivalent to the bound aconitate was then added to the juice for the precipitation. The insoluble aconitates which precipitated during the subsequent evaporation of the juices were removed by some appropriate means at a later point in the sugar recovery system. 

Shoemaker, H. E., E. O. McLean, and P, F. Pratt. 1961. Buffer methods for determining lime requirement of soils with appreciable amounts of extractable aluminum. Soil Sci. Soc. Am. Proc. 25 274-277. 

Estimate the mass and volume of sludge produced from untreated wastewater without and with the use of ferric chloride for the enhanced removal of total suspended solids (TSS). Also estimate the amount of lime required for the specified ferric chloride dose. Assume that 60 percent of the TSS is removed in the primary settling tank without the addition of chemicals, and that the addition of ferric chloride results in an increased removal of TSS to 85 percent. Also, assume that the following data apply to this situation ... 

Determine the mass of lime required to convert the ferric chloride to ferric hydroxide Fe( OH)y The relevant equation is... 

Calculation of Stoichiometric Lime Required IN THE Lime-Soda Process... 

To summarize, let Mqm be the total lime requirement M odAsh be the total soda ash requirement and Msouds be the total sohds produced. Mqm is equal to the amount of lime used for the removals of the carbonate hardness of calcium (Mcaocaucoj). the carbonate hardness of magnesium (McaOMgHcOj). the noncarbonate hardness of magnesium (McaOMgCa). the requirement to neutralize the dissolved carbon dioxide (Mqioco) and the requirement to raise the pH to 10.4 for the precipitation of Mg(OH)2. Thus,... 

SO4 = 216.0 mg/L. (a) Check if the number of equivalents of positive and negative ions are balanced. For a flow of 25,000 mVd and a complete removal of hardness, calculate (b) the lime requirement, (c) the soda ash requirement, and (d) the mass of solids and volume of sludge produced. Assume that the lime used is 90% pure and the soda ash used is 85% pure. Also, assume that the specific gravity of the sludge is 1.04. 

In Problem 10.8 for a complete removal of hardness, calculate the lime requirement. Assume that the lime used is 90% pure. 

Now, letting McaOMoj be the kilograms of lime required to react with the phosphorus,... 

Obtain a relation for the lime required for a lumped system to reach the average temperature (T, + T ), where 7) is the initial temperature and is the temperature of the environment. 

Vitamin K status can be assessed by a functional test, called the "prothrombin time test," which involves measuring the lime required to form a blood clot. The test is performed as follows. A blood sample is withdrawn from a subject and immediately mixed with citric acid. Citric acid is a chelator, which means that it can form a tight complex with ions, such as calcium ions. The chelator prevents the interaction of calcium ions with the blood-clotting proteins and thus prevents these proteins from forming a blood clot in the sample. Calcium ions, it should be noted, are required for supporting the activity of several blood clotting proteins. The "citrated blood" is placed in a machine called a fibrometer. The fibrometer is used to detect increases in the viscosity of the blood over a period. 

Fig. 5. Amounts of lime required to raise the pH of two sewage samples to various levels.

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