摘要:

With all the talk about water plant optimization, we would do well to review a few of the operational techniques for filters. The normal cycle for a rapid sand filter begins with the placement of a cleaned filter into service and follows through the steps of filter ripening, effluent production, and subsequent head loss increase. It finally results in particle and turbidity breakthrough, bringing the need for the backwash sequence. During these stages, flow rates through the filter can increase or decrease, and different quality pretreated water can be introduced. What is done with these steps can greatly affect finished water quality.

ISSN:0149-8029    

DOI:10.1002/j.1551-8701.1996.tb00546.x

出版商:Wiley    

年代:1996

数据来源: WILEY

摘要:

This month's question asks if it would be helpful for an entry‐level operator to attend a regional conference to learn more about the drinking water industry. The answer urges the attendance of conferences for reasons that include: networking with professional peers; new answers/solutions to old questions/problems on topics such as water treatment, distribution, water quality, regulations and compliance, benchmarking, partnerships for managing small systems, etc., etc. The article provides an inset on Electronic Help Resources Available on Line.

ISSN:0149-8029    

DOI:10.1002/j.1551-8701.1996.tb00547.x

出版商:Wiley    

年代:1996

数据来源: WILEY

摘要:

The Kern County Housing Authority operates a farm labor housing center near Shafter, California. The housing center only operates six months of the year, when transient laborers work the nearby farms. The well supplying water for the North Shafter Farm Labor Center began experiencing nitrate contamination several years ago, causing the authority to purchase bottled water for the residents. To reduce the expense associated with bottled water, the authority obtained a grant to construct an ion exchange nitrate removal plant for the center. The treatment plant, which began operation in early April 1994, produces 480 gpm (30 L/s) of water with nitrate reduced from 62 mg/L to 30 mg/L.

ISSN:0149-8029    

DOI:10.1002/j.1551-8701.1996.tb00548.x

出版商:Wiley    

年代:1996

数据来源: WILEY

摘要:

The dangers of installing large valves are considerable and prompted the invention of the valve choker. Previously, installation required two or three people to lift and align an 800‐lb (400‐kg) valve, often in a wet, muddy hole. Keeping the valve in an upright position while bolting it to a flange surface was problematic, and supporting it by hand could result in crushed limbs or strained backs. The valve choker prevents these kinds of injuries and is a successful safety measure for all our valve installations. A list of materials and construction information is included.

ISSN:0149-8029    

DOI:10.1002/j.1551-8701.1996.tb00549.x

出版商:Wiley    

年代:1996

数据来源: WILEY