1. A position detecting apparatus located across a wall configured to partition a first space and a second space that is adjacent to the first space, and has a different pressure from that of the first space, said position detecting apparatus using light to detect a position of an object that is located in the first space, said position detecting apparatus comprising:
a detector in the second space, and configured to receive the light from the object;
a polarizer configured to define a polarization direction of the light; and
an optical element located on the wall, and closer to said detector than said polarizer.
2. A position detecting apparatus according to claim 1, wherein one of the first and second spaces is maintained vacuum.
3. An exposure apparatus comprising:
a position detecting apparatus located across a wall configured to partition a first space and a second space that is adjacent to the first space, and has a different pressure from that of the first space, said position detecting apparatus using light to detect a position of an object that is located in the first space,
wherein said position detecting apparatus includes:
a detector located in the second space, and configured to received the light from the object;
a polarizer configured to define a polarization direction of the light; and
an optical element located on the wall, and closer to said detector than said polarizer.
4. An exposure apparatus according to claim 3, wherein the exposure apparatus is configures to expose the object using an electron beam.
5. An exposure apparatus according to claim 3, wherein the exposure apparatus is configured to expose the object using extreme ultraviolet light.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of inhibiting scale deposition from spent liquor in a pulp mill evaporator or concentrator, the method comprising:
(a) determining a level of scale deposition in the pulp mill evaporator or concentrator; and
(b) adding an effective amount of a scale-inhibiting composition to the black liquor, if the determined level of scale deposition is above a predetermined level;
(c) wherein the scale-inhibiting composition includes one or more compounds selected from the group consisting of: monocarboxylic acids; polycarboxylic acids; fatty acids; low and high molecular weight aromatic aliphatic and aromatic sulfonic acids acids; esters, anhydrides, and amides thereof; low and high molecular weight amines; and combinations thereof.
2. The method of claim 1, further comprising:
(a) inserting a probe having a temperature-regulated outer surface into the pulp mill evaporator or concentrator;
(b) contacting the temperature-regulated outer surface with the spent liquor;
(c) measuring a thermal conductivity of the temperature-regulated outer surface, wherein the thermal conductivity is dependent upon an amount of scale deposition on the temperature-regulated outer surface;
(d) transmitting the measured thermal conductivity to a controller;
(e) determining a level of scale deposition in the pulp mill evaporator or concentrator, based upon the measured thermal conductivity; and
(f) adding an effective amount of the scale-inhibiting composition to the spent liquor, if the determined level of scale deposition is above the predetermined level.
3. The method of claim 2, including intermittently measuring the thermal conductivity on the temperature-regulated outer surface of the probe.
4. The method of claim 2, including continuously measuring the thermal conductivity on the temperature-regulated outer surface of the probe.
5. The method of claim 1, wherein the spent liquor has a solids content below about 50%.
6. The method of claim 1, wherein the spent liquor is derived from a process selected from the group consisting of: kraft, alkaline, sulfite, and neutral sulfite semichemical.
7. The method of claim 1, wherein the scale includes one or more scales selected from the group consisting of: burkeite, sodium sulfate, sodium carbonate, entrapped organic material, calcium carbonate, and combinations thereof.
8. The method of claim 1, including adding about 1 ppm to about 2,000 ppm of one or more of the compounds, based on black liquor.
9. The method of claim 1, wherein the organic carboxylic acid is selected from the group consisting of: acrylic-maleic acid copolymers in about a 1:1 ratio and having molecular weight from about 1,000 to about 50,000; ethylene-vinyl acetate-methacrylic acid copolymers having molecular weight from about 1,000 to about 50,000; phthalic acid and other aromatic vic-dicarboxylic acids; linseed oil polymer; and combinations thereof.
10. The method of claim 9, wherein the linseed oil polymer is heat polymerized in the presence of maleic anhydride and optionally cross-linked with pentaerythritol.
11. The method of claim 1, wherein the organic carboxylic acid includes one or a mixture of fatty acids andor fatty acid esters with chain length from about C5 to about C50.
12. The method of claim 1, wherein the organic carboxylic acid, organic fatty acid, andor fatty acid ester is derived from a biodiesel manufacturing process.
13. The method of claim 1, wherein the organic carboxylic acid, organic fatty acid, andor fatty acid ester is derived from one or more phases of biodiesel manufacturing processes selected from the group consisting of: addition of acid to the fatty acid salts solution of a crude fatty acid alkyl esters phase; addition of acid to the fatty acid salts solution of a crude glycerin phase; acidulation of at least one biodiesel manufacturing process stream containing at least one fatty acid salts component; transesterification reactions involving triglycerides; and combinations thereof.
14. The method of claim 1, wherein the organic carboxylic acid, organic fatty acid, andor fatty acid ester includes a component selected from the group consisting of: methyl esters, ethyl esters, salts, methanol, ethanol, glycerin, water, and combinations thereof.
15. The method of claim 1, wherein the organic carboxylic acid, organic fatty acid, andor fatty acid ester includes one or more components selected from the group consisting of: C6 to C24 saturated and unsaturated fatty acids; C6 to C24 saturated and unsaturated fatty acids salts; esters thereof with C1 to C6 mono-, di-, and trihydric alcohols; and one or more inorganic salts.
16. The method of claim 1, wherein the organic fatty acid is selected from the group consisting of: palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidic acid, eicosenoic acid, behenic acid, lignoceric acid, tetracosenic acid, and combinations thereof.
17. The method of claim 1, wherein the organic acid anhydride or amide is selected from the group consisting of: octadecenylhexadecenyl-succinic anhydride; octadecenylisooctadecenyl-succinic anhydride; fatty acid anhydride blends; 1,8-naphthalenedicarboxylic acid amides; and combinations thereof.
18. The method of claim 1, wherein the sulfonic acid is selected from the group consisting of: styrenesulfonic-maleic acid copolymers having a 1:1 ratio and molecular weight from about 1,000 to about 50,000; sulfonated naphthalene-formaldehyde condensates; alkylsulfonic acids with the alkyl chain length from about C5 to about C18; and combinations thereof.
19. The method of claim 1, wherein the amine is selected from the group consisting of: linear or cross-linked polyethyleneimines with molecular weight from about 1,000 to about 100,000; carboxymethyl or dithiocarbamate derivatives of linear or cross-linked polyethyleneimine with molecular weight from about 1,000 to about 100,000; N-vinylpyrrolidone-diallyldimethylammonium copolymers; 4-piperidinols; and combinations thereof.
20. The method of claim 1, wherein the pulp mill evaporator is a multiple-effect evaporator.
21. The method of claim 1, including monitoring the concentration of the scale-inhibiting composition in the spent liquor by using an inert fluorescent tracer.
22. A method of monitoring scale deposition from spent liquor in a pulp mill evaporator or concentrator, the method comprising:
(a) inserting a probe having a temperature-regulated outer surface into the pulp mill evaporator or concentrator;
(b) contacting the temperature-regulated outer surface with the spent liquor;
(c) measuring a thermal conductivity on the temperature-regulated outer surface, wherein the thermal conductivity is dependent on an amount of scale deposition on the temperature-regulated outer surface;
(d) transmitting the measured thermal conductivity to a controller; and
(e) determining a level of scale deposition in the pulp mill evaporator or concentrator, based upon the measured thermal conductivity.
23. The method of claim 22, including a temperature gradient between the spent liquor and the temperature-regulated outer surface of the probe from about 70\xb0 C. to about 80\xb0 C.
24. The method of claim 22, wherein the scale includes one or more scales selected from the group consisting of: burkeite, sodium sulfate, sodium carbonate, entrapped organic material, calcium carbonate, and combinations thereof.
25. The method of claim 22, including intermittently or continuously measuring the thermal conductivity on the temperature-regulated outer surface of the probe.