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The feasibility of a two-stage process involving carbon dioxide capturing and a photobioreaction (containing microalgae cells of Spirulina maxima) was investigated for the dual purpose of CO 2 sequestration and wastewater remediation. The study systematically demonstrated the capability of CO 2 removal through wet scrubbing using diluted wastewater as the scrubbing liquid and the potential of biomass growth in the CO 2 -enriched wastewater. The NaOH-alkalized wastewater provided a CO 2 absorption capacity approximately equal to 0.5 g CO 2 g −1 NaOH at 0.5 M, and the absorbed CO 2 was effectively converted into usable bicarbonate to support the growth of S. maxima. The biomass productivity using the CO 2 -enriched wastewater (30% diluted) was 0.036 g L −1 d −1 , which was in line with the productivity obtained from the controlled growth tests using NaHCO 3 as the carbon source. Dilution of raw dairy (milk processing) wastewater was necessary as high chemical oxygen demand (COD) loading inhibited the growth of S. maxima. However, with sufficient dilution, as the COD was less than 300 mg L −1 , the COD was effectively removed (79%) during the microalgae cultivation period, as were NH 4 + (51%) and PO 4 − (35%) to lesser extents. The uptake of organic carbon indicated that Spirulina grew mixotrophically in the wastewater. Furthermore, by virtue of the hydroxide reaction with CO 2 that form aqueous carbonates (lowering the pH) and the photosynthetic activity that consumes carbonates (increase the pH), the solution pH can effectively be used as the controlling parameter in operation of the system.

Atomic absorption spectrophotometric methods, developed for determination of arsenic , selenium and zinc concentration in finger and foot bone from blackfoot disease patients(BFDPs), by the amputation were developed. Thirty-four cases of BFDPs at the most strict clinical examination and thirty cases of Non-BFDPs(NBFDP) from the traffic accidents, nearly at the same condition were compared as control . Arsenic has been claimed to be a major causative agent of blackfoot disease(BFD) in the southwestern coast of Taiwan. Previously we published some reports also supported this conception , as with i ncreasing of zero, first second, third and fourth clinical stages. The increasing of the arsenic concentration in the blood, hair and urine were happened during the BFD progressed. Although at the third and fourth stages, arsenic decreased may be affected by the antagonistic effect of selenium and zinc. For the purpose to this facts, this experiment was carried to check whether at the fourth stages, the concentration of arsenic in BFDPs finger and foot bone by amputation are higher than NBFDPs and even in the blood of BFDPs at the fourth stage or not. The result showed arsenic concentration in finger and foot bone of BFDPs were a little higher than NBFDPs and with the rate of 0.09±0.05 µg/g and 0.08±0.04 µg/g. Zinc concentration in BFDPs finger and foot bone by amputation were lower than the NBFDPs and with the rate of 52.9±20.2µg/g >35.0±13.8 µg/g and had a significantly difference with p < 0.05. The same condition, happened to the BFDPs blood zinc and bone zinc . BFDPs had lower blood zinc concentration than bone zinc with the rate of 35.0 ±l3.8µg/g >3.59±1.36 µg/g. Selenium concentration of BFDPs in finger and foot bone by amputation were also had a lower selenium concentration than the NBFDPs and with the rate of 0.07±0.04 j,g/g<0.17±0.04 µg/g. It had a significantly difference with p < 0.01. Further more, when we compared selenium concentration of BFDP by amputation in finger and foot bone with the BFDP blood at the fourth stages. The results were on the contrary. The bone selenium concentration of BFDPs were higher than the BFDPs blood selenium with the rate of 0.08±0.05 µg/g>0.04±0.02 µg/ml and had significantly difference with p<0.05. Selenium and zinc may have some antagonistic effect with arsenic and from this stand point of the role, selenium and zinc as either inhibitory agents of BFD. Therefore selenium and zinc may assess in the blood as diagnostic or prognostic aids in BFD.

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