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The Hsinchu Science-based Industrial Park (HSIP) is the main manufacturing base of "high-tech" commodities of Taiwan. The treatment of wastewater of HSIP produces hard-to-dewater sludge, at a rate of 80 Mg/day, which is resistant to chemical conditioning, whose disposal is costly. The use of chemical flocculation and physical conditioning, including heating and freezing and thawing, on the dewaterability of HSIP sludge was examined in this Note. The dewaterability of the original sludge was poor, and neither chemical flocculation nor thermal heating enhanced its dewatering. However, the freezing and thawing could release up to 83% of moisture from the sludge body; in line with this occurence, the settleability and filterability of the sludge were considerably enhanced. The ice front developed during freezing, which could destroy the floc network, release the interstitial water, and might correspond to the successful conditioning using freezing and thawing. [ABSTRACT FROM AUTHOR]

Co-conditioning and dewatering behaviors of alum sludge and waste activated sludge were investigated. Two different sludges were mixed at various ratios (2:1; 1:1; 1:2; 1:4) for study. Capillary suction time (CST) and specific resistance to filtration (SRF) were utilized to assess sludge dewaterability. Relatively speaking, waste activated sludge, though of higher solid content, was more difficult to be dewatered than alum sludge. It was found that sludge dewaterability and settlability became better with increasing fraction of alum sludge in the mixed sludge. Dosage required of the cationic polyelectrolyte (KP-201C) for dewatering was reduced as well. It is proposed that alum sludge acts as skeleton builder in the mixed sludge, and renders the mixed sludge more incompressible which is beneficial for sludge dewatering. Implications of the results of the study to the sludge management plan for Taipei City that generates both alum sludge and waste activated sludge at significant amount are also discussed. The current sludge treatment and disposal plan in Metropolitan Taipei could be made more cost-effective. [ABSTRACT FROM AUTHOR]

Reaction of fluoride with waste oyster shell was studied. To enhance the stability and adsorption capacity, oyster shell was coated with Al(OH) 3 and the adsorption behaviors were compared with the uncoated one. When at low fluoride concentration (<30 mg/L), fluoride removal efficiency decreased with increasing pH, and the adsorption could be modeled by Langmuir isotherm. At high fluoride concentration (>100 mg/L), linear adsorption isotherm fitted better, in which the adsorption capacity of fluoride increased linearly with increasing equilibrium fluoride concentration. The coated oyster shell showed higher adsorption capacity and wider workable pH range. From XPS analysis, the presence of CaF 2 was confirmed by the peak at 684.7 eV when fluoride concentration increased. It was noted that magnesium content of waste oyster shell reacted with fluoride to form significant fractions of MgF 2 whose corresponding peak was detected at 685.6-685.8 eV. For coated oyster shell, fluoride reacted with Ca, Mg, and Al. The reaction mechanism was mainly adsorption at low initial concentration, and precipitation-dominated at higher concentration., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Rainwater harvesting systems (RWHSs), a pilot-scale one (PSR) and a full-scale one (FSR), at a university campus in Taipei were assessed. Characteristics of harvested rainwater were analyzed, including pH, electrical conductivity (EC), turbidity, alkalinity, dissolved organic carbon (DOC), total coliform (TC), concentration of 14 metals (Al, Ca, K, Mg, Na, Cu, Fe, Mn, V, Zn, Cd, Cr, Pb and Ni) and concentration of 3 anions (Cl(-), SO(4)(2-) and NO(3)(-)). Rainwater in the FSR had pH in the neutral range and high alkalinity, whereas those of the PSR were acidic and with low buffer ability because of different catchment materials. Median concentrations of 14 metals from two RWHSs were low, except for Na, Ca, K and Mg. Anions, including Cl(-), NO(3)(-), and SO(4)(2-) showed much higher concentration in winter, indicating the influences of marine source and northeast monsoon. Effects of 14-day storage were examined and it was found that pH did not change, while EC, turbidity and DOC slightly decreased. Concentrations of anions and metals were stable, and TC counts of harvested rainwater increased in the beginning, and then declined with storage time. During antecedent dry days, total suspended particulates (TSPs) were collected and their dissolution was examined. Preliminary correlation of wet and dry depositions with rainwater quality was explored.

A route for the synthesis of the treatment train of sewage sludge is proposed, and the conceptual design stage is demonstrated, using local sludge as an example.

Erythema multiforme (EM), a cutaneous or mucocutaneous disorder, occurs primarily in young adults. To evaluate the precipitating factors, clinical courses, and treatment of this disease in children, 30 cases aged from 1 month old to 15 years of age were studied retrospectively from Jan 1988 to Aug 1998. Twenty-three cases were diagnosed as minor type; the other 7 were of major type (Stevens-Johnson syndrome). Mycoplasma infection was identified in 4 patients, and adenovirus in one patient with EM minor. Cytomegalovirus was found in one EM major patient. Anticonvulsant administration before the skin lesions were recorded in 5 EM major patients and 2 EM minor patients. All cases received supportive treatment during admission. Besides, 6 of 7 patients with EM major, and 11 of 23 EM minor (Group A) received systemic corticosteroid at a dose equal to prednisolone 1-2 mg/kg/day for 3-14 days. One EM major patient and 11 patients with EM minor (Group B) received supportive care only. One EM minor patient with acute idiopathic thrombocytopenia purpura was treated with intravenous immunoglobulin. The mean duration of course of EM minor was 11.8 +/- 2.9 days, and it was 25.1 +/- 9.8 days for EM major. No mortality and no sequelae were noted. The average disease course and hospitalization time were not significantly different between Group A and B: (11.4 +/- 3.1 days vs 12.4 +/- 2.9 days, p = 0.45); (5.4 +/- 2.0 days vs 6.3 +/- 3.1 days, p = 0.47). This study demonstrated that infections, especially mycoplasma, and anticonvulsants play important roles in childhood EM. The skin lesions of EM minor subsided within 2 weeks, and EM major recovered completely within 6 weeks. Systemic corticosteroid may be beneficial to EM major, but probably is unnecessary for patients with EM minor.

In order to determine the geographical distribution of Ancylostoma duodenale and Necator americanus in Taiwan, 2,759 fresh stool samples were collected from 5th-grade school children of both sexes among 43 preliminary schools in 16 counties, and then examined by means of the modified test-tube filter-paper cultivation method for identification of the filariform larvae of hookworm. Both species of A. duodenale and N. americanus are widespread in Taiwan. The overall infection rate was 20.00%. The rate of A. duodenale, N. americanaus and mixed infection of both species was 9.85%, and 7.75% and 2.39% respectively. Geographically, N. americanus (12.64%) predominated over A. duodenale (5.43%) in the north (Ilan, Taipei, Taoyuan, Hsinchu and Miaoli) and the east (Taitung) areas. On the contrary, A. duodenale (13.40%) predominated over N. americanus (5.63%) in the central (Nantou, Taichung, Changhua and Yunlin), the south (Chiayi, Tainan, Kaohsiung and Pingtung) and the east (Hualien) areas. On the other hand, the rate of infection on the offshore island (Penghu) was much lower (1.19%) than the others (21.10-21.29%).

Paragonimus westermani is an endemic disease and has had scattered distribution in Northern Taiwan for the long period of 108 years. In order to know the current status of the prevalence of this disease in Taipei County, an investigation by means of examination of snail, crab and stool for identification of cercariae, metacercariae and ova of Paragonimus westermani was carried out in five small highly endemic foci-Alilao, Shengkeng, Shuangchi, Shihjen and Taiping from July 1984 to June 1985. The results obtained are summarized as follows: The infection rate for 17, 412 fresh-water snails, Semisulcospira libertina, the first intermediate host and for 180 fresh-water crabs, Eriocheir japoniucs, the second intermediate host was both negative in the first four places. On the contrary, the rate for 879 fresh-water snails, Semisulcospira libertina, for 298 fresh-water crabs, Potamon miyazaki and Potamon dehaani and for 45 school-children was zero, 26.8% and zero respectively, in the last one. Based on the above findings, it is concluded that in the last 20 years, Paragonimus westermani might probably be under control in the former areas which are now developed districts. This development has probably influenced the prevalence and distribution of the disease. But it is still prevalent in the latter area located in remote undeveloped mountain.